E N T R Y- L E V E L

EXAM REVIEW
F O R R E S P I R AT O R Y
CARE: GUIDELINES
FOR SUCCESS

SECOND EDITION

WILLIAM V. WOJCIECHOWSKI

A u s t r a l i a C a n a d a M e x i c o S i n g a p o r e S p a i n U n i t e d K i n g d o m U n i t e d S t a t e s
 Entry-Level Exam Review for Respiratory Care: Guidelines for Success
by William V. Wojciechowski

Business Unit Director: Project Editor:

William Brottmiller Stacy Prus DISCLAIMER
Acquisitions Editor: Production Coordinator: The author, contributors, and publisher make no claim
Candice Janco John Mickelbank that persons using this review book are guaranteed
success on the National Board for Respiratory Care
(NBRC) Entry-Level (CRTT) Examination. The National
Development Editor: Art/Design Coordinator: Board for Respiratory Care does not endorse this
Patricia A. Gaworecki Mary Colleen Liburdi publication. The NBRC has merely granted permission to
Delmar Publications, Inc. to use the Entry-Level (CRTT)
Examination Matrix in this publication. The examination
Editorial Assistant: Cover Design: items and analyses contained in this publication have
Elizabeth O’Keefe TDB Publishing Service been written by the author and contributors based solely
on their own education, experience, and knowledge of the
profession of respiratory care. The NBRC offers no
Executive Marketing Manager: opinion or endorsements of these examination items and
Dawn F. Gerrain analyses.

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under license means—graphic, electronic, or mechanical, Entry-level exam review for respiratory care:
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 Dedication
To my children, Alison, Maria, and Matthew,
who raise more questions than are found in this book,
and whose answers are found in no book.
 Contents

CHAPTER-MATRIX TABLE vii

PREFACE ix

ACKNOWLEDGMENTS xi

CONTRIBUTORS xiii

INTRODUCTION 1
TEXT OBJECTIVES 1
ORGANIZATION OF BOOK CONTENT 1
HOW TO USE EACH CHAPTER 1
ENTRY-LEVEL EXAMINATION STRUCTURE 3
ENTRY-LEVEL EXAMINATION MATRIX 3
NBRC CERTIFICATION EXAMINATION FOR
ENTRY-LEVEL CERTIFIED RESPIRATORY THERAPISTS (CRTS) 4
LEVEL OF QUESTIONS 12
ENTRY-LEVEL EXAMINATION ITEM FORMAT 13
MULTIPLE TRUE-FALSE (K-TYPE) QUESTIONS 13
GENERAL ENTRY-LEVEL EXAMINATION INFORMATION 14
ENTRY-LEVEL EXAMINATION PREPARATION 14

CHAPTER 1 • TEST PREPARATION 17

THE APPLICATION 17
THE MATRIX AND CLINICAL PRACTICE 18
STUDY HINTS 19
THE WEEK OF THE EXAMINATION 21
THE DAY BEFORE THE EXAMINATION 21
THE DAY OF THE EXAMINATION 21
EXPECT TO PASS 22

CHAPTER 2 • PRETEST 23
PRETEST ASSESSMENT 27
CHAPTER 2 PRETEST: MATRIX CATEGORIES 46
PRETEST ANSWERS AND ANALYSES 48
REFERENCES 82

CHAPTER 3 • CLINICAL DATA 83

CLINICAL DATA ASSESSMENT 90
CHAPTER 3: MATRIX CATEGORIES 132
CLINICAL DATA ANSWERS AND ANALYSES 134

v
 REFERENCES 192

CHAPTER 4 • EQUIPMENT 193

EQUIPMENT ASSESSMENT 199
MATRIX CATEGORIES 233
EQUIPMENT ANSWERS, ANALYSES, AND REFERENCES 235
REFERENCES 279

CHAPTER 5 • THERAPEUTIC PROCEDURES 280

THERAPEUTIC PROCEDURES ASSESSMENT 288
MATRIX CATEGORIES 329
THERAPEUTIC PROCEDURES—ANSWERS AND ANALYSES 331
REFERENCES 382

CHAPTER 6 • POSTTEST 383

POSTTEST ASSESSMENT 387
POSTTEST: MATRIX CATEGORIES 405
POSTTEST ANSWERS AND ANALYSES 407
REFERENCES 437

APPENDIX 1 • QUICK REFERENCE MATERIAL—CLINICAL DATA 439

APPENDIX 2 • QUICK REFERENCE MATERIAL—SPIROGRAM, 446

ECG, PULMONARY ARTERY CATHETER,
AND CAPNOGRAPHY

APPENDIX 3 • QUICK REFERENCE MATERIAL—MECHANICAL 453

VENTILATION WAVEFORMS

vi
 Chapter-Matrix Table

Chapter Matrix Section Pages/Questions Pages/Analyses

2 All matrix sections 27–45/1–140 48–81/1–140

3 IA1 to IA2 90–101/1–95 134–158/1–95
3 IB1 to IB10 104–119/96–210 158–182/96–210
3 IC1 to IB2 123–129/211–250 182–191/211–250
4 IIA1 to IA2 199–212/1–111 235–256/1–111
4 IIB1 to IIB3 215–229/112–211 257–278/112–211
5 IIIA1 to IIID10 288–303/1–110 331–354/1–110
5 IIIE1 to IIIG2 307–325/111–235 354–381/111–235
6 All matrix sections 387–404/1–140 407–436/1–140

Chapters 3, 4, and 5 have been restructured. The questions are no longer randomly interspersed throughout
each chapter, as in the first edition. In this edition, questions and analyses are presented in sequential order ac-
cording to the Entry-Level Examination Matrix. For example, Chapter Three, “Clinical Data,” has three sections:
IA, IB, and IC.
All the questions referring to the matrix category IA appear in sequence. No questions from matrix categories
IB or IC are included in that portion of the chapter. Each matrix area is segregated within its corresponding chap-
ter. The analyses pertaining to the questions are also sequenced in the same manner.

vii
 Preface
The purpose of the second edition of The Entry-Level Exam Review for Respiratory Care: Guidelines for Suc-
cess is to assist Entry-Level Examination candidates to prepare for the credentialing exam based on the expanded
matrix introduced in July 1999. Every five years, the National Board for Respiratory Care (NBRC) conducts a job
analysis for the Entry-Level and Advanced Practitioner Examinations. Respiratory therapists, department heads,
educators, and physicians throughout the United States complete thousands of job-analysis surveys. These surveys
ascertain the specific tasks performed by certified and registered respiratory therapists. The questions, therefore,
are job related. The job analysis also ensures the content validity of the credentialing examinations. Each five-year
cycle results in more application and analysis questions, with fewer recall questions appearing on the exam. First-
time technicians taking the 1999 revised Entry-Level Examination had only a 46.5% pass rate (refer to the table
on page x). This new edition can help you prepare for a better exam performance with these features:

• Organization is centered on the 1999 NBRC Exam Matrix in a question/answer format that provides the stu-
dent with analyses for each answer.
• Pretest and posttest evaluations identify baseline competencies and areas of continued remediation.
• Matrix scoring forms appear in every chapter, along with the complete NBRC examination content outline
for reference and review.
• CD-ROM software provides a practice test environment that simulates the actual computerized NBRC
exam. Students are able to take the test in learning or test modes, with answers and analyses provided. A
timing function is also available to more closely resemble the actual exam.

There is no substitute for preparation and practice. This book has been designed as a tool to help you progress
through the credentialing process. Good luck in your professional endeavors.

ix
 NBRC Entry-Level Exam Data
100

90
Average ELE 1st-time technician pass rate 1990 - March 1999 = 69.4%
80

70
Percent Pass Rate (%)

%
*
60

50
4 6
*
*
40

30

20

10

0 1994 1994 1999

1990 1991 1992 1993 March July/Nov 1995 1996 1997 1998 March 1999
First-Time Technicians 70.6 71.1 72.2 73.6 72.7 66.6 68.47 67.83 66.8 67 66.9 46
Repeat Technicians 28.4 27.2 25.4 27.3 20 19.9 24.2 23 20 26.1 26.9 6.2
Repeat Therapists 35.7 37.6 31.8 36.3 27.2 29.8 34.8 31.2 34 37 39.9 7.8
*ELE exam revised based on 1993 job analysis: 1st-time technician pass rate: 65.1%
*ELE exam revised based on 1997 job analysis: 1st-time technician pass rate: 46%.
 Acknowledgments
I wish to take this opportunity to extend my appreciation to my colleagues who contributed to the writing of
The Entry-Level Examination Review for Respiratory Care: Guidelines for Success second edition. I am certain
that the composite of their clinical experiences and educational expertise will greatly benefit the candidates who
use this book to prepare for the NBRC Entry-Level Examination.
Sincere thanks and gratitude are extended to Deanna Winn for her painstaking efforts and patience that she dis-
played throughout the typing of the manuscript. The fact that she maintained an amiable attitude despite the hard-
ships was inspirational. Her amiability is now a known attribute of her character. How she relishes compiling an
art manuscript amazes me further (inside joke).
Special thanks to Fred Hill, MA, RRT for meticulously reviewing the entire manuscript and making insightful
suggestions. Special thanks is also extended to Helen A. Jones, RRT, for contributing Chapter 1, which sets the
tempo for the remainder of the book.
I am also grateful for the professional assistance provided by Patty Gaworecki, Tara Carter, Doris Smith, and
Dawn Gerrain of Delmar Thomson Learning.
Lastly, I welcome suggestions and critiques of all varieties from the reading audience in an effort to enhance
the utility of this book.
W. V. W.

xi
 Contributors
Karen M. Boudin, MA, RRT Fred Hill, MA, RRT
Inservice Instructor Assistant Professor
Department of Respiratory Therapy Department of Cardiorespiratory Care
Stanford University Hospital University of South Alabama
Stanford, CA Mobile, AL
Kim Cavanagh, MEd, RRT Bradley A. Leidich, MSEd, RRT
Technical Director Associate Professor/Director
Respiratory Therapy Department Respiratory Care Programs
Mercy Medical Harrisburg Area Community College
Daphne, AL Harrisburg, PA
Robert P. DeLorme, MEd, RRT Nancy Jane Deck-Lorance, BS, RRT
Program Director Program Director
Respiratory Therapy Technology Respiratory Therapist Program
Gwinnett Technical Institute Rose State College
Lawrenceville, GA Midwest City, OK
Larry Arnson, MS, RRT Anna W. Parkman, MBA, RRT
Director of Clinical Education/Instructor Program Director
Respiratory Therapy Technology Program Respiratory Care Program
Gwinnett Technical Institute University of Charleston
Lawrenceville, GA Charleston, WV
F. Herbert Douce, MS, RRT Glenda Jean Fisher, BA, RRT
Assistant Professor/Director of Respiratory Therapy Director of Clinical Education
Respiratory Therapy Division Respiratory Care Program
The Ohio State University University of Charleston
Columbus, OH Charleston, WV
Charles M. Fatta, MBA, RRT Leslee Harris Smith, MS, RRT
Albuquerque Technical-Vocational Institute Respiratory Therapy Program Head/
Albuquerque, NM Assistant Professor
Northern Virginia Community College
Marie A. Fenske, EdD, RRT
Annandale, VA
Program Director
Respiratory Care Steve Wehrman, RRT
Gateway Community College Assistant Professor/Program Director
Phoenix, AZ University of Hawaii
Kapiolani Community College
Robert R. Fluck, Jr., MS, RRT
Honolulu, HI
Associate Professor
Department of Respiratory Care and Theodore R. Wiberg, PhD, RRT
Cardiorespiratory Sciences Chairman of Health Sciences
State University of New York Richard A. Henson School of Science and Technology
Health Science Center–Syracuse Salisbury State University
Syracuse, NY Salisbury, MD
Bill Galvin, MSED, RRT, CPFT David N. Yonutas, MS, RRT
Assistant Professor, Division of Allied Health Program Coordinator
Program Director, Respiratory Care Program Health Sciences
Gwynedd Mercy College Santa Fe Community College
Gwynedd, PA Gainesville, FL
Lezli Heyland, BS, RRT
Francis Tuttle Vocational Technical Center
Oklahoma City, OK

xiii
 INTRODUCTION

Text Objectives Chapter 2: Pretest

Chapter 3: Clinical Data
The objectives of this text are as follows: Chapter 4: Equipment
1. preparing candidates for the National Board of Chapter 5: Therapeutic Procedures
Respiratory Care (NBRC) Entry-Level Exami- Chapter 6: Posttest
nation
2. providing Entry-Level Examination candidates
the opportunity to complete a computer-based
How to Use Each Chapter
practice examination
Introduction
3. assisting respiratory care students in entry-level
and advanced practitioner programs to prepare The introduction provides the following information: (1)
for course examinations states this text’s objectives, (2) explains how to use this
4. preparing practitioners for legal credentialing review book, (3) describes the makeup and content areas
(state) examinations contained in the NBRC Entry-Level Examination, (4)
5. streamlining the credentialing examination provides information on how to prepare for the Entry-
preparation process by focusing the candidate’s Level Examination, and (5) describes the three levels of
attention on the Entry-Level Examination Matrix questions contained on the Entry-Level Examination.
6. determining entry-level content areas requiring Refer to the matrix of the examination to be familiar
remediation with the concepts that are presented on the credentialing
7. presenting an organized approach to examina- examination. You should focus on the specific material
tion preparation described in each matrix item. Doing so will make your
study time more efficient. Do not neglect this critical
8. reinforcing learning by providing several cross-
step in the credentialing examination review process. To
references for each question
assist you with this task, all the questions in this book
9. clarifying theoretical and clinical aspects of
have been categorized into their content areas via the
entry-level respiratory care via analysis of each
Entry-Level Examination Matrix Scoring Form located
question
in Chapters 2 through 6. You should use the scoring of
10. providing a self-assessment mechanism for your results on these forms to develop a prescription for
credentialed respiratory care practitioners study. Collate your results, and focus your attention on
11. supplementing hospital in-service programs the areas that require remediation.
12. assisting respiratory care educators with devel-
oping evaluation instruments for course exami- Chapter 1 • Test Preparation
nations
Embarking on a credentialing examination review process
13. assisting respiratory care educators with the requires a positive attitude. The content of the first chapter
development of Entry-Level Examination in this review book focuses your attention on the task
review sessions at hand. As formidable an undertaking as the review
process seems, a number of practical and relatively
easy plans of action are presented to help alleviate your
Organization of Book Content anxiety and stress. Suggestions are provided for orga-
This book consists of six chapters: nizing a realistic timetable for using the examination
review material presented in this text. You are encour-
Introduction aged to make the effort to implement the strategies pro-
Chapter 1: Examination Preparation vided for your use.

1
Chapter 2 • Pretest (140 Items, Analyses, you read material in the references. After you have thor-
and References) oughly reviewed the questions, analyses, matrix desig-
nations, and references, proceed to the next chapter.
The pretest should be performed without the benefit of
advance preparation. You should simply take the pretest Chapter 3 • Clinical Data (250 Items,
to establish a baseline for the measurement of your Analyses, and References)
progress through this study guide. Make sure that you
allow yourself three hours of uninterrupted time to Chapter 3 enables you to evaluate your knowledge in
complete the pretest. That length of time is provided by the four categories within this content area:
the NBRC for this credentialing examination. Place A. Reviewing patient records and recommending
yourself in a quiet, well-lit, ventilated area. Be seated diagnostic procedures
on a chair with a back support at a desk or table. B. Collecting and evaluating clinical information
The pretest offers you the opportunity to identify
Entry-Level Examination content areas that might re- C. Performing procedures and interpreting results
quire remediation. The pretest parallels the Entry-Level D. Assessing and developing a therapeutic plan
Examination. The items on the pretest match the testing and recommending modifications
categories found on the Entry-Level Examination. Among the four categories encountered in the con-
Table I-1 indicates the content areas and the item dis- tent area of clinical data, there are 68 matrix designa-
tribution comprising the pretest. tions. Twenty-five of these matrix items are included on
Table I-1: Pretest Content Areas and Item Distribution the NBRC Entry-Level Examination.
Content Areas Number of Items
Because there is no way to determine which 25 items
relating to clinical data will appear on the Entry-Level Ex-
I. Clinical Data 25 amination, the candidate needs to experience questions
II. Equipment 36 from each matrix item. This chapter provides you with
III. Therapeutic Procedures 79
practice questions that encompass virtually all the possible
TOTAL 140
types that might be encountered on the actual examination.
After completing the pretest, use the answer sheet In addition to thoroughly studying the questions,
provided in the book to determine your score. Use the analyses, and references for the questions that were ei-
Entry-Level Examination Matrix Scoring Form, located ther incorrectly answered or answered correctly by
after the analyses, to score each content category and de- guessing, you are encouraged to note the matrix desig-
termine content areas that require remediation. Review nation of those questions and refer to the Entry-Level
and study the analyses of the questions you have an- Examination Matrix for a clear description of the con-
swered incorrectly, as well as the analyses of the ques- cept being tested. Remember to use the Entry-Level
tions that you might have gotten correct by answering Examination Matrix Scoring Form associated with this
with an “educated” guess. In other words, also review chapter to help identify areas of strength and weakness
the analyses of any questions of which you are unsure. regarding Clinical Data.
After studying each question and analysis, refer to Again, as with all the other chapters, use the answer
the Entry-Level Examination Matrix located within sheet provided at the beginning of each assessment.
Chapter 2. The matrix outlines all the tasks that fall You should strive to achieve a score of 75% in this
within the purview of the Entry-Level Examination. chapter, or 187 correct answers.
You must become familiar with the range of knowledge Chapter 4 • Equipment (211 Items,
and cognitive areas for which you are responsible on
Analyses, and References)
this credentialing examination. The manner in which to
achieve this familiarity is to study the Entry-Level Ex- This chapter offers you the opportunity to evaluate your un-
amination Matrix, as well. derstanding of the two categories within this content area:
When you have reviewed the appropriate matrix cat- A. Selecting, obtaining, and assuring equipment
egories, read and study the material indicated by the ref- cleanliness
erences. The references are provided to offer you a more
B. Assembling, checking, and correcting equip-
detailed account of the concept associated with each
ment malfunctions; performing quality control
question and analysis. By reading the matrix designa-
tion before proceeding to the references, you will be These two categories are represented by 90 matrix
more focused on the information pertinent to the matrix designations. Only 36 items from this section appear on
category and will be less likely to go off on tangents as the Entry-Level Examination.

2 Introduction
 This chapter offers you the opportunity to sample the exhaustive review of the Entry-Level Examination Ma-
entire gamut of matrix items, because the assessment trix. The posttest content areas and item distribution are
presented here contains 211 items regarding equipment. listed in Table I-2.
Again, you are urged to completely review the materials Table I-2: Posttest Content Areas and Item Distribution
that require remediation and cross-reference the items to
the Entry-Level Examination Matrix. Use the answer Content Areas Number of Items
sheet located in front of the test, and employ the Entry- I. Clinical Data 25
Level Examination Matrix Scoring Form found after the II. Equipment 36
analyses. A score of 75% would result from correctly III. Therapeutic Procedures 79
answering 158 of the 211 items presented.
TOTAL 140

Chapter 5 • Therapeutic Procedures

(235 Items, Analyses, and References) The posttest should indicate the degree of progress
you have made while studying this review book. The
This chapter enables you to evaluate your comprehen- posttest should be approached seriously and with con-
sion of the seven categories within this content area: fidence, which should have developed over the last few
A. Educating patients and maintaining records, weeks. As with the pretest, the posttest should also be
communication, and infection control graded immediately, and, for the final time, remedia-
tion (questions, analyses, and matrix) and cross-
B. Maintaining an airway and removing bron-
referencing must follow.
chopulmonary secretions
C. Assuring ventilation and oxygenation Entry-Level Examination
D. Assessing patient response
E. Modifying therapy/making recommendations Structure
based on patient’s response; recommending The examination matrix is a detailed content outline
pharmacologic agents describing the content categories that will appear on the
F. Resuscitating in various emergency situations Entry-Level Examination. You should become famil-
G. Assisting physician; conducting pulmonary re- iarized with the examination matrix. Keep in mind that
habilitation and home care the items appearing on the credentialing examination
have been developed from this outline.
Chapter 5 provides you with 235 sample questions The Entry-Level Examination Matrix provides you
from this content area. Therefore, to achieve a score with the information that is evaluated on this creden-
(75%) on this assessment, you must minimally answer tialing examination. The matrix of this test helps eval-
176 questions correctly. The Entry-Level Examination uate whether the candidate possesses the cognitive
Matrix contains 90 matrix designations from the seven skills necessary to function as a Certified Respiratory
content categories found with Therapeutic Procedures. Technician (CRT) at the entry level.
Only 79 items appear on the NBRC Entry-Level Ex-
amination, however. As before, careful attention to the
remediation process and cross-referencing the ques-
Entry-Level Examination
tions to the Entry-Level Examination Matrix should Matrix
prepare you well for this content area.
The Entry-Level Examination Matrix is composed of
Chapter 6 • Posttest (140 Items, Analyses, three major content areas:
and References) I. Clinical Data
The posttest is intended to provide you with feedback re- II. Equipment
lated to the remediation performed in response to the re- III. Therapeutic Procedures
sults obtained on the pretest. The posttest is structured to
parallel the NBRC Entry Level Examination in terms of Each of these content areas is divided into a number
content area and item distribution. The following table of subcategories. The subcategories are subdivided into
demonstrates the organization of the posttest. more specific content elements. The complete Entry-
Chapter 6 contains a posttest tailored after the Entry- Level Examination Matrix follows in Table I-3. Be-
Level Examination. This evaluation tool represents the come familiar with this matrix as you prepare for the
culmination of a substantial effort on your part and an examination.

Introduction 3
NBRC Certification Examination for
Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
N

N
(4) dead space to tidal volume ratio
I. Select, Review, Obtain, (VD/VT) x
(5) non-invasive monitoring [e.g.,
and Interpret Data
capnography, pulse oximetry,
SETTING: In any patient care set- transcutaneous O2/CO2] x
ting, the respiratory care practi- g. results of cardiovascular monitoring
tioner reviews existing clinical data (1) ECG, blood pressure, heart rate x
and collects or recommends ob- (2) hemodynamic monitoring [e.g.,
taining additional pertinent clinical central venous pressure, cardiac
data. The practitioner interprets all output, pulmonary capillary wedge
data to determine the appropriate- pressure, pulmonary artery pressures,
ness of the prescribed respiratory mixed venous O2, C(a-v̄)O2, shunt
care plan and participates in the studies (Q̇s/Q̇t)] x
development of the plan. h. maternal and perinatal/neonatal history
7 14 4 and data [e.g., Apgar scores, gestational
age, L/S ratio, pre/post-ductal
A. Review existing data in patient record,
oxygenation studies] x x
and recommend diagnostic procedures. 2* 3 0
2. Recommend the following procedures to
1. Review existing data in patient record;
obtain additional data:
a. patient history [e.g., present illness,
a. X-ray of chest and upper airway, CT
admission notes, respiratory care
scan, bronchoscopy, ventilation/
orders, progress notes] x** x
perfusion lung scan, barium swallow x
b. physical examination [e.g., vital signs,
b. Gram stain, culture, and sensitivities x
physical findings] x x
c. spirometry before and/or after
c. lab data [e.g., CBC, chemistries/
bronchodilator, maximum voluntary
electrolytes, coagulation studies,
ventilation, diffusing capacity, functional
Gram stain, culture and sensitivities,
residual capacity, flow-volume loops,
urinalysis] x
body plethysmography, nitrogen
d. pulmonary function and blood gas
washout distribution test, total lung
results x
capacity, CO2 response curve, closing
e. radiologic studies [e.g., X-rays of
volume, airway resistance,
chest/upper airway, CT, MRI] x
bronchoprovocation, maximum
f. monitoring data
inspiratory pressure (MIP), maximum
(1) pulmonary mechanics [e.g.,
expiratory pressure (MEP) x
maximum inspiratory pressure
d. blood gas analysis, insertion of arterial,
(MIP), vital capacity] x
umbilical, and/or central venous
(2) respiratory monitoring [e.g., rate,
pulmonary artery monitoring lines x
tidal volume, minute volume, I:E,
e. lung compliance, airway resistance,
inspiratory and expiratory
lung mechanics, work of breathing x
pressures; flow, volume, and
f. ECG, echocardiography, pulse oximetry,
pressure waveforms] x
transcutaneous O2/CO2 monitoring x
(3) lung compliance, airway resistance,
work of breathing x B. Collect and evaluate clinical information. 3 7 0
1. Assess patient’s overall cardiopulmonary
status by inspection to determine:

*The number in each column is the number of item in that content area and the cognitive level contained in each examina-
tion. For example, in category I.A., two items will be asked at the recall level, three items at the application level, and no
items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the re-
spective column (Recall, Application, and Analysis).

4 Introduction
 APP
APP

ANA
ANA

LIC
LIC

REC
REC

ATI
ATI

LYS
LYS

ALL
ALL

ON
ON

IS
IS

N
N

N
N
a. general appearance, muscle wasting, b. presence of, or changes in,
venous distention, peripheral edema, pneumothorax or subcutaneous
diaphoresis, digital clubbing, cyanosis, emphysema, other extra-pulmonary air,
capillary refill x consolidation and/or atelectasis,
b. chest configuration, evidence of pulmonary infiltrates x
diaphragmatic movement, breathing c. position of chest tube(s), nasogastric
pattern, accessory muscle activity, and/or feeding tube, pulmonary artery
asymmetrical chest movement, catheter (Swan-Ganz), pacemaker,
intercostal and/or sternal retractions, CVP, and other catheters x x
nasal flaring, character of cough, d. presence and position of foreign bodies x
amount and character of sputum x e. position of, or changes in,
c. transillumination of chest, Apgar score, hemidiaphragms, hyperinflation, pleural
gestational age fluid, pulmonary edema, mediastinal
2. Assess patient’s overall cardiopulmonary shift, patency, and size of major airways x
status by palpation to determine: 8. Review lateral neck X-ray to determine:
a. heart rate, rhythm, force x a. presence of epiglottitis and subglottic
b. asymmetrical chest movements, tactile edema x
fremitus, crepitus, tenderness, secretions b. presence or position of foreign bodies x
in the airway, tracheal deviation, c. airway narrowing x
endotracheal tube placement x 9. Perform bedside procedures to determine:
3. Assess patient’s overall cardiopulmonary a. ECG, pulse oximetry, transcutaneous
status by percussion to determine O2/CO2 monitoring, capnography,
diaphragmatic excursion and areas of mass spectrometry x
altered resonance x b. tidal volume, minute volume, I:E x
4. Assess patient’s overall cardiopulmonary c. blood gas analysis, P(A•a)O2, alveolar
status by auscultation to determine the ventilation, VD/VD, Q̇s/Q̇t, mixed venous
presence of: sampling x
a. breath sounds [e.g., normal, bilateral, d. peak flow, maximum inspiratory
increased, decreased, absent, unequal, pressure (MIP), maximum expiratory
rhonchi or crackles (rales), wheezing, pressure (MEP), forced vital capacity,
stridor, friction rub] x timed forced expiratory volumes [e.g.,
b. heart sounds, dysrhythmias, murmurs, FEV1], lung compliance, lung mechanics x
bruits e. apnea monitoring, sleep studies,
c. blood pressure x respiratory impedance plethysmography x
5. Interview patient to determine: f. tracheal tube cuff pressure, volume x
a. level of consciousness, orientation to 10. Interpret results of bedside procedures
time, place, and person, emotional state, to determine:
ability to cooperate x a. ECG, pulse oximetry, transcutaneous
b. presence of dyspnea and/or orthopnea, O2 /CO2 monitoring, capnography, mass
work of breathing, sputum production, spectrometry x
exercise tolerance, and activities of b. tidal volume, minute volume, I:E x
daily living x c. blood gas analysis, P(A-a)O2, alveolar
c. physical environment, social support ventilation, VD /VT, Q̇s/Q̇t, mixed venous
systems, nutritional status x sampling x
6. Assess patient’s learning needs [e.g., age d. peak flow, maximum inspiratory
and language appropriateness, education pressure (MIP), maximum expiratory
level, prior disease and medication pressure (MEP), forced vital capacity,
knowledge] x timed forced expiratory volumes [e.g.,
7. Review chest X-ray to determine: FEV1], lung compliance, lung mechanics x
a. position of endotracheal or tracheostomy e. apnea monitoring, sleep studies,
tube, evidence of endotracheal or respiratory impedance plethysmography x
tracheostomy tube cuff hyperinflation x f. tracheal tube cuff pressure, volume x

Introduction 5
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C. Perform procedures and interpret results. 2 3 0 2. Participate in development of respiratory
1. Perform and/or measure the following: care plan [e.g., case management, develop
a. ECG, pulse oximetry, transcutaneous and apply protocols, disease management
O2 /CO2 monitoring x education] x x
b. spirometry before and/or after
bronchodilator, maximum voluntary
ventilation, diffusing capacity, functional
residual capacity, flow-volume loops,
II. Select, Assemble, and
body plethysmography, nitrogen washout Check Equipment for Proper
distribution test, total lung capacity, Function, Operation and
CO2 response curve, closing volume, Cleanliness
airway resistance x
c. arterial sampling and blood gas SETTING: In any patient care
analysis, co-oximetry, P(A-a)O2 x setting, the respiratory therapist
d. ventilator flow, volume, and pressure selects, assembles, and assures
waveforms, lung compliance x cleanliness of all equipment used
2. Interpret results of the following: in providing respiratory care. The
a. spirometry before and/or after therapist checks all equipment
bronchodilator, maximum voluntary and corrects malfunctions.
ventilation, diffusing capacity, functional 14 22 0
residual capacity, flow-volume loops,
body plethysmography, nitrogen washout A. Select, obtain, and assure equipment
distribution test, total lung capacity, CO2 cleanliness. 5 8 0
response curve, closing volume, airway 1. Select and obtain equipment appropriate
resistance, bronchoprovocation x to the respiratory care plan:
b. ECG, pulse oximetry, transcutaneous a. oxygen administration devices
O2 /CO2 monitoring x (1) nasal cannula, mask, reservoir mask
c. arterial sampling and blood gas (partial rebreathing, non-rebreathing),
analysis, co-oximetry, P(A-a)O2 x face tents, transtracheal oxygen
d. ventilator flow, volume, and pressure catheter, oxygen conserving cannulas x
waveforms, lung compliance x (2) air-entrainment devices,
tracheostomy collar and T-piece,
D. Determine the appropriateness and
oxygen hoods and tents x
participate in the development of the
(3) CPAP devices x
respiratory care plan, and recommend
b. humidifiers [e.g., bubble, passover,
modifications. 0 1 4
cascade, wick, heat moisture exchanger] x
1. Determine the appropriateness of the
c. aerosol generators [e.g., pneumatic
prescribed respiratory care plan and
nebulizer, ultrasonic nebulizer] x
recommend modifications where indicated:
d. resuscitation devices [e.g., manual
a. analyze available data to determine
resuscitator (bag-valve), pneumatic
pathophysiological state x
(demand-valve), mouth-to-valve mask
b. review planned therapy to establish
resuscitator] x
therapeutic plan x
e. ventilators
c. determine appropriateness of prescribed
(1) pneumatic, electric, microprocessor,
therapy and goals for identified
fluidic x
pathophysiological state x
(2) non-invasive positive pressure x
d. recommend changes in therapeutic
f. artificial airways
plan if indicated (based on data) x
(1) oro- and nasopharyngeal airways x
e. perform respiratory care quality
(2) oral, nasal and double-lumen
assurance x x
endotracheal tubes x
f. implement quality improvement
(3) tracheostomy tubes and buttons x
program x x
(4) intubation equipment [e.g.,
g. review interdisciplinary patient and
laryngoscope and blades, exhaled
family care plan x x
CO2 detection devices] x

6 Introduction
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g. suctioning devices [e.g., suction B. Assemble and check for proper equipment
catheters, specimen collectors, function, identify and take action to
oropharyngeal suction devices] x correct equipment malfunctions, and
h. gas delivery, metering and clinical perform quality control. 9 14 0
analyzing devices x 1. Assemble, check for proper function, and
(1) regulators, reducing valves, identify malfunctions of equipment:
connectors and flow meters, air/ a. oxygen administration devices
oxygen blenders, pulse-dose (1) nasal cannula, mask, reservoir
systems x mask (partial rebreathing, non-
(2) oxygen concentrators, air rebreathing), face tents,
compressors, liquid-oxygen systems x transtracheal oxygen catheter,
(3) gas cylinders, bulk systems and oxygen conserving cannulas x
manifolds x (2) air-entrainment devices,
(4) capnograph, blood gas analyzer tracheostomy collar and T-piece,
and sampling devices, co-oximeter, oxygen hoods and tents x
transcutaneous O2/CO2 monitor, (3) CPAP devices x
pulse oximeter x b. humidifiers [e.g., bubble, passover,
(5) CO, He, O2 and specialty gas cascade, wick, heat moisture exchanger] x
analyzers x c. aerosol generators [e.g., pneumatic
i. patient breathing circuits nebulizer, ultrasonic nebulizer] x
(1) IPPB, continuous mechanical d. resuscitation devices [e.g., manual
ventilation x resuscitator (bag-valve), pneumatic
(2) CPAP, PEEP valve assembly x (demand-valve), mouth-to-valve mask
j. aerosol (mist) tents x resuscitator] x
k. incentive breathing devices x e. ventilators x
l. percussors and vibrators x (1) pneumatic, electric, microprocessor,
m. manometers and gauges fluidic x
(1) manometers—water, mercury and (2) non-invasive positive pressure x
aneroid, inspiratory/expiratory f. artificial airways x
pressure meters, cuff pressure (1) oro- and nasopharyngeal airways x
manometers x (2) oral, nasal and double-lumen
(2) pressure transducers x endotracheal tubes x
n. respirometers [e.g., flow-sensing (3) tracheostomy tubes and buttons x
devices (pneumotachometer), volume (4) intubation equipment [e.g.,
displacement] x laryngoscope and blades, exhaled
o. electrocardiography devices [e.g., ECG CO2 detection devices] x
oscilloscope monitors, ECG machines g. suctioning devices [e.g., suction
(12-lead), Holter monitors] x catheters, specimen collectors,
p. vacuum systems [e.g., pumps, oropharyngeal suction devices] x
regulators, collection bottles, pleural h. gas delivery, metering and clinical
drainage devices] x analyzing devices x
q. metered dose inhalers (MDIs), MDI (1) regulators, reducing valves,
spacers x connectors and flow meters, air/
r. Small Particle Aerosol Generators oxygen blenders, pulse-dose systems x
(SPAGs) x (2) oxygen concentrators, air
s. bronchoscopes x compressors, liquid-oxygen systems x
2. Assure selected equipment cleanliness (3) gas cylinders, bulk systems and
[e.g., select or determine appropriate manifolds x
agent and technique for disinfection and/or (4) capnograph, blood gas analyzer
sterilization, perform procedures for and sampling devices, co-oximeter,
disinfection and/or sterilization, monitor transcutaneous O2/CO2 monitor,
effectiveness of sterilization procedures] x pulse oximeter x

Introduction 7
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(5) CO, HE, O2, and specialty gas (4) intubation equipment [e.g.,
analyzers x laryngoscope and blades, exhaled
i. patient breathing circuits CO2 detection devices] x
(1) IPPB, continuous mechanical g. suctioning devices [e.g., suction
ventilation x catheters, specimen collectors,
(2) CPAP, PEEP valve assembly x oropharyngeal suction devices] x
j. aerosol (mist) tents x h. gas delivery, metering and clinical
k. incentive breathing devices x analyzing devices x
l. percussors and vibrators x (1) regulators, reducing valves,
m. manometers—water, mercury and connectors and flow meters, air/
aneroid, inspiratory/expiratory pressure oxygen blenders, pulse-dose
meters, cuff pressure manometers x systems x
n. respirometers [e.g., flow-sensing (2) oxygen concentrators, air
devices (pneumotachometer), volume compressors, liquid-oxygen systems x
displacement] x (3) gas cylinders, bulk systems and
o. electrocardiography devices [e.g., ECG manifolds x
oscilloscope monitors, ECG machines (4) capnograph, blood gas analyzer
(12-lead), Holter monitors] x and sampling devices, co-oximeter,
p. vacuum systems [e.g., pumps, transcutaneous O2 /CO2 monitor,
regulators, collection bottles, pleural pulse oximeter x
drainage devices] x i. patient breathing circuits x
q. metered dose inhalers (MDIs), (1) IPPB, continuous mechanical
MDI spacers x ventilation x
r. Small Particle Aerosol Generators (2) CPAP, PEEP valve assembly x
(SPAGs) x j. aerosol (mist) tents x
2. Take action to correct malfunctions of k. incentive breathing devices x
equipment: l. percussors and vibrators x
a. oxygen administration devices m. manometers—water, mercury and
(1) nasal cannula, mask, reservoir mask aneroid, inspiratory/expiratory pressure
(partial rebreathing, non-rebreathing), meters, cuff pressure manometers x
face tents, transtracheal oxygen n. respirometers [e.g., flow-sensing
catheter, oxygen conserving cannulas x devices (pneumotachometer), volume
(2) air-entrainment devices, displacement] x
tracheostomy collar and T-piece, o. vacuum systems [e.g., pumps,
oxygen hoods and tents x regulators, collection bottles, pleural
(3) CPAP devices x drainage devices] x
b. humidifiers [e.g., bubble, passover, p. metered dose inhalers (MDIs),
cascade, wick, heat moisture exchanger] x MDI spacers x
c. aerosol generators [e.g., pneumatic 3. Perform quality control procedures for: x
nebulizer, ultrasonic nebulizer] x a. blood gas analyzers and sampling
d. resuscitation devices [e.g., manual devices, co-oximeters x
resuscitator (bag-valve), pneumatic b. pulmonary function equipment, ventilator
(demand-valve), mouth-to-valve mask volume/flow/pressure calibration x
resuscitator] x c. gas metering devices x
e. ventilators x
(1) pneumatic, electric, microprocessor,
fluidic x
(2) non-invasive positive pressure x
f. artificial airways
(1) oro- and nasopharyngeal airways x
(2) oral, nasal and double-lumen
endotracheal tubes x
(3) tracheostomy tubes and buttons x

8 Introduction
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d. communicate information relevant to
III. Initiate, Conduct, and coordinating patient care and discharge
planning [e.g., scheduling, avoiding
Modify Prescribed conflicts, sequencing of therapies] x
Therapeutic Procedures e. apply computer technology to patient
SETTING: In any patient care management [e.g., ventilator waveform
setting, the respiratory therapist analysis, electronic charting, patient
communicates relevant informa- care algorithms] x
tion to members of the health- f. communicate results of therapy and
care team, maintains patient alter therapy per protocol(s) x
records, initiates, conducts, and 3. Protect patient from noscomial infection
modifies prescribed therapeutic by adherence to infection control policies
procedures to achieve the de- and procedures [e.g., universal/standard
sired objectives and assists the precautions, blood and body fluid
physician with rehabilitation and precautions] x
home care. B. Conduct therapeutic procedures to
15 36 28
maintain a patent airway and remove
bronchopulmonary secretions. 2 3 0
1. Maintain a patent airway, including the
A. Explain planned therapy and goals
care of artificial airways:
to patient, maintain records and
a. insert oro- and nasopharyngeal airway,
communication, and protect patient from
select endotracheal or tracheostomy
nosocomial infection. 2 3 0
tube, perform endotracheal intubation,
1. Explain planned therapy and goals to
change tracheostomy tube, maintain
patient in understandable terms to achieve
proper cuff inflation, position of
optimal therapeutic outcome, counsel
endotracheal or tracheostomy tube x
patient and family concerning smoking
b. maintain adequate humidification x
cessation, disease management education x
c. extubate the patient x
2. Maintain records and communication:
d. properly position patient x
a. record therapy and results using
e. identify endotracheal tube placement
conventional terminology as required
by available means x
in the health-care setting and/or by
2. Remove bronchopulmonary secretions:
regulatory agencies [e.g., date, time,
a. perform postural drainage, perform
frequency of therapy, medication, and
percussion and/or vibration x
ventilatory data] x
b. suction endotracheal or tracheostomy
b. note and interpret patient’s response
tube, perform nasotracheal or
to therapy
orotracheal suctioning, select closed-
(1) effects of therapy, adverse reactions,
system suction catheter x
patient’s subjective and attitudinal
c. administer aerosol therapy and
response to therapy x
prescribed agents [e.g., bronchodilators,
(2) verify computations and note
corticosteroids, saline, mucolytics] x
erroneous data x
d. instruct and encourage
(3) auscultatory findings, cough and
bronchopulmonary hygiene techniques
sputum production and characteristics x
[e.g., coughing techniques, autogenic
(4) vital signs [e.g., heart rate,
drainage, positive expiratory pressure
respiratory rate, blood pressure,
(PEP) device, intrapulmonary percussive
body temperature] x
ventilation (IPV), Flutter®, High
(5) pulse oximetry, heart rhythm,
Frequency Chest Wall Oscillation
capnography x
(HFCWO)] x
c. communicate information regarding
patient’s clinical status to appropriate C. Conduct therapeutic procedures to achieve
members of the health-care team x adequate ventilation and oxygenation. 2 5 9

Introduction 9
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1. Achieve adequate spontaneous and 6. Perform spirometry/determine vital
artificial ventilation: capacity, measure lung compliance and
a. instruct in proper breathing techniques, airway resistance, interpret ventilator flow,
instruct in inspiratory muscle training volume and pressure waveforms,
techniques, encourage deep breathing, measure peak flow x
instruct and monitor techniques of 7. Monitor mean airway pressure, adjust
incentive spirometry x and check alarm systems, measure tidal
b. initiate and adjust IPPB therapy x volume, respiratory rate, airway pressures,
c. select appropriate ventilator I:E, and maximum inspiratory pressure
d. initiate and adjust continuous (MIP) x
mechanical ventilation when no settings 8. Measure FiO2 and/or liter flow x
are specified and when settings are 9. Monitor cuff pressures x
specified [e.g., select appropriate tidal 10. Auscultate chest and interpret changes
volume, rate, and/or minute ventilation] in breath sounds x
e. initiate nasal/mask ventilation, initiate
E. Modify and recommend modifications
and adjust external negative pressure
in therapeutics and recommend
ventilation [e.g., culrass]
pharmacologic agents. 3 12 17
f. initiate and adjust ventilator modes [e.g.,
1. Make necessary modifications in therapeutic
A/C, SIMV, pressure-support ventilation
procedures based on patient response:
(PSV), pressure-control ventilation (PCV)] x
a. terminate treatment based on patient’s
g. administer prescribed bronchoactive
response to therapy being administered
agents [e.g., bronchodilators,
b. modify IPPB:
corticosteroids, mucolytics] x
(1) adjust sensitivity, flow, volume,
h. institute and modify weaning procedures x
pressure, FiO2 x
2. Achieve adequate arterial and tissue
(2) adjust expiratory retard x
oxygenation:
(3) change patient—machine interface
a. initiate and adjust CPAP, PEEP, and
[e.g., mouthpiece, mask] x
non-invasive positive pressure x
c. modify incentive breathing devices [e.g.,
b. initiate and adjust combinations of
increase or decrease incentive goals] x
ventilatory techniques [e.g., SIMV,
d. modify aerosol therapy:
PEEP, PS, PCV] x
(1) modify patient breathing pattern x
c. position patient to minimize hypoxemia,
(2) change type of equipment, change
administer oxygen (on or off ventilator),
aerosol output x
prevent procedure-associated
(3) change dilution of medication,
hypoxemia [e.g., oxygenate before and
adjust temperature of the aerosol x
after suctioning and equipment changes] x
e. modify oxygen therapy:
D. Evaluate and monitor patient’s response (1) change mode of administration,
to respiratory care. 2 6 2 adjust flow, and FiO2 x
1. Recommend and review chest X-ray x (2) set up or change an O2 blender x
2. Interpret results of arterial, capillary, and (3) set up an O2 concentrator or liquid
mixed venous blood gas analysis O2 system x
3. Perform arterial puncture, capillary blood f. modify bronchial hygiene therapy [e.g.,
gas sampling, and venipuncture; obtain alter position of patient, alter duration
blood from arterial or pulmonary artery of treatment and techniques, coordinate
lines; perform transcutaneous O2/CO2, sequence of therapies, alter equipment
pulse oximetry, co-oximetry, and used and PEP therapy] x
capnography monitoring x g. modify artificial airways management:
4. Observe changes in sputum production (1) alter endotracheal or tracheostomy
and consistency, note patient’s subjective tube position, change endotracheal
response to therapy and mechanical or tracheostomy tube x
ventilation x (2) change type of humidification
5. Measure and record vital signs, monitor equipment x
cardiac rhythm, evaluate fluid balance (3) initiate suctioning x
(intake and output) x (4) inflate and deflate the cuff x

10 Introduction
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h. modify suctioning: i. change aerosol drug dosage or
(1) alter frequency and duration of concentration
suctioning x j. insert chest tube
(2) change size and type of catheter x 3. Recommend use of pharmacologic agents
(3) alter negative pressure x [e.g., anti-infectives, anti-inflammatories,
(4) instill irrigating solutions x bronchodilators, cardiac agents, diuretics,
i. modify mechanical ventilation: mucolytics/proteolytics, narcotics,
(1) adjust ventilator settings [e.g., sedatives, surfactants, vasoactive agents]
ventilatory mode, tidal volume, FiO2, F. Treat cardiopulmonary collapse according
inspiratory plateau, PEEP and to the following protocols. 2 4 0
CPAP levels, pressure support and 1. BCLS x
pressure control levels, non-invasive 2. ACLS x
positive pressure, alarm settings] 3. PALS x
(2) change patient breathing circuitry, 4. NRP x
change type of ventilator x
G. Assist the physician, initiate and conduct
(3) change mechanical dead space x
pulmonary rehabilitation and home care. 2 3 0
j. modify weaning procedures
1. Act as an assistant to the physician,
2. Recommend the following modifications
performing special procedures that include
in the respiratory care plan based on
the following:
patient response:
a. bronchoscopy x
a. change FiO2 and oxygen flow
b. thoracentesis x
b. change mechanical dead space
c. tracheostomy x
c. use or change artificial airway [e.g.,
d. cardioversion x
endotracheal tube, tracheostomy]
e. intubation x
d. change ventilatory techniques [e.g.,
2. Initiate and conduct pulmonary rehabilitation
tidal volume, respiratory rate, ventilatory
and home care within the prescription:
mode, inspiratory effort (sensitivity),
a. explain planned therapy and goals to
PEEP/CPAP, mean airway pressure,
patient in understandable terms to
pressure support, inverse-ratio
achieve optimal therapeutic outcome,
ventilation, non-invasive positive
counsel patient and family concerning
pressure]
smoking cessation, disease
e. use muscle relaxant(s) and/or
management x
sedative(s)
b. assure safety and infection control x
f. wean or change weaning procedures
c. modify respiratory care procedures for
and extubation
use in the home x
g. institute bronchopulmonary hygiene
d. conduct patient education and
procedures [e.g., PEP, IS, IPV, CPT]
disease management programs x
h. modify treatments based on patient
response [e.g., change duration of TOTALS 36 72 32
therapy, change position]

Introduction 11
Level of Questions A.
B.
asbestosis
Adult Respiratory Distress Syndrome (ARDS)
On all its credentialing examinations, the NBRC pre- C. pulmonary emphysema
sents test items on three cognitive levels: recall, appli- D. pneumonia
cation, and analysis.
ANSWER: C
RECALL: Examination items written at this cogni-
tive level test the ability to recall or recognize specific ANALYSIS: Test items presented at the analysis
information. This information can be terminology, level evaluate the candidate’s ability to analyze and/or
facts, principles, and so on. Information learned at the synthesize information in order to arrive at a solution.
recall level involves remembering memorized material. The following question represents an example of an
An example of a test item at the recall level follows. analysis-level item:

The function of the body plethysmograph is based A patient is receiving volume-cycled mechanical
on ______ law. ventilation in the control mode. The following arter-
ial blood gas data were obtained:
A. Avogadro’s
B. Boyle’s PO2 93 torr
C. Charles’
PCO2 25 torr
D. Dalton’s
pH 7.56
ANSWER: B HCO 3̄ 22 mEq/liter

APPLICATION: Examination questions posed at

this cognitive level test the candidate’s ability to relate Which ventilator adjustment should be made at this
concepts, principles, facts, or information to new or time?
changing situations or mathematical problems. The two A. Institute 5 cm H2O PEEP.
items presented next illustrate application-level questions. B. Increase the FiO2.
C. Increase the tidal volume.
1. The following data were obtained from a closed- D. Decrease the ventilatory rate.
circuit, helium-dilution study performed on a 64-
year-old male: ANSWER: D

Helium added: 650 ml The distribution of items on the Entry-Level Exami-

Percentage of initial helium: 9.5% nation, based on the cognitive level (recall, application,
and analysis), is outlined in Table I-4.
Percentage of final helium: 6.0%
Table I-4
Helium absorption factor: 100 ml
Cognitive Level
Collected gas temperature: 25ºC
Content Category Recall Application Analysis

I. Clinical Data
Calculate this person’s functional residual capacity
A. Review patient records;
(FRC). recommend diagnostic
A. 3.9 liters procedures 2 3 0
B. Collect and evaluate
B. 3.8 liters
clinical information 3 7 0
C. 3.0 liters C. Perform procedures;
D. 2.1 liters interpret results 2 3 0
D. Assess and develop
ANSWER: A therapeutic plan;
recommend
2. With which pulmonary disease is this FRC value modifications 0 1 4
consistent? SUBTOTAL (25) 7 14 4

12 Introduction
Table I-4: continued completions. Select one that is best in each case, then
Cognitive Level blacken the corresponding space on the answer sheet.
Content Category Recall Application Analysis
Multiple-Choice Questions
II. Equipment
A. Select and obtain; EXAMPLE On an electrocardiogram, the T wave
ensure cleanliness 5 8 0 represents ______.
B. Assemble and check;
correct malfunctions;
A. atrial depolarization.
perform quality control 9 14 0 B. ventricular depolarization.
C. ventricular repolarization.
SUBTOTAL (36) 14 22 0 D. atrial repolarization.
III. Therapeutic Procedures
THE ONE BEST RESPONSE IS C.
A. Educate patients;
maintain records and
communication; Multiple-choice test items require the candidate to
infection control 2 3 0 choose the one best response from four plausible selec-
B. Maintain airway; tions. The three selections that are not correct answers
remove bronchopul- are called distractors. The style of the multiple-choice
monary secretions 2 3 0 test item is constructed to present all four choices as
C. Achieve adequate
ventilation and
plausible responses. The candidate must determine
oxygenation 2 5 9 which selection represents the one best response.
D. Assess patient 2 6 2 The phrase “one best response” refers to the choice
response that, among those presented, most accurately completes
E. Recommend and the stem of the question. The best response may not ac-
modify therapeutics;
tually be the precise answer; however, among the four
recommend pharma-
cologic agents 3 12 17 selections available, it represents the best choice.
F. Treat cardiopulmonary
collapse by protocol
G. Assist physician;
2 4 0 Multiple True-False (K-Type)
conduct pulmonary
rehabilitation and
Questions
home care 2 3 0
EXAMPLE Which pathologic conditions are asso-
SUBTOTAL (79) 15 36 28 ciated with a decreased tactile fremitus?
TOTAL (140) 36 72 32 I. atelectasis
II. pneumothorax
III. thickened pleura
Entry-Level Examination IV. pleural effusion
Item Format A. I, III only
The Entry-Level Examination is composed of two types B. II, IV only
of questions: multiple-choice and multiple true-false or C. II, III, IV only
K-type questions. At various points throughout the ex- D. I, III, IV only
amination, you will encounter questions referring to di-
THE CORRECT RESPONSE IS C.
agrams, waveforms, or tracings. In some cases, you will
be asked a series of questions pertaining to the diagrams,
With this type of question, you must select the state-
waveforms, or tracings. Again, these questions follow
ments that refer to or describe the stem. The statements
the multiple-choice and multiple true–false formats.
range in number from three to five and are designated
The instructions for the Entry-Level Examination
as Roman numerals. All the true statements relating to
read as follows.
the stem must be selected.
DIRECTIONS: Each of the questions or incomplete The process of elimination is easier to employ with
statements is followed by four suggested answers or this type of question than with a regular multiple-

Introduction 13
choice question. For example, referring to the sample Again, your score on the 160-item Entry-Level Exami-
question, suppose you were certain that III and IV were nation will be based n the 140 questions that have al-
true concerning the stem and that I was false, but you ready been statistically screened. Therefore, as you
were uncertain about II. You could automatically elim- work through the examination, do not labor too long
inate A and D knowing that I was false. Choice B could over questions that appear difficult. Use your time effi-
be eliminated, because it does not contain III (which ciently. If a question seems too difficult, move on to the
you know is true). Because no selection is provided next question. Then, when you reach the end of the ex-
listing III and IV only, C represents the logical choice. amination, return to the question(s) with which you had
As you read through the responses available, you difficulty. You do not want to waste time pondering a
should indicate the true responses with some kind of question that you might not be able to answer.
mark (such as X or T). You will save time by not hav- The NBRC will provide you with one sheet of paper
ing to reread certain selections. to use for performing calculations, writing formulas,
etc. This sheet of paper must be handed to the exami-
General Entry-Level nation supervisor before you leave the room after the
examination is completed.
Examination Information Before you begin the computer-based examination,
you will be allowed to familiarize yourself with the
1. Every word in the stem of each question is es- NBRC computer-testing process by taking a 10-minute
sential and meaningful. Do not “read more into” practice test. You will be permitted to terminate the
the question than that which is presented. Ac- practice examination before the 10-minute practice ses-
cept each question for what it states. sion ends if you are comfortable with the computer-
2. All data reported on the examination are assumed testing process.
to have been obtained under standard pressure When you complete the examination, review only
conditions (i.e., 760 mm Hg or torr) unless other- those questions you definitely were not able to answer.
wise specified in the stem of the question, or a Do not change any answers unless you are absolutely
scenario referring to a sequence of questions. certain your initial response is wrong. If you are uncer-
3. Pressures are generally reported in terms of the tain about an answer you have made, do not change the
unit torr. One torr equals 1 mm Hg. answer because (assuming you prepared well for this
4. Whenever you perform calculations, do not in- examination) you have likely made the correct choice.
sert the numerical values only into the equation Your first inclination is ordinarily correct, based on the
used. Insert the appropriate unit along with the fact you prepared for this test.
numerical value. Adhering to this practice al- Make sure you do not leave any items unanswered.
lows you to cancel some of the units in the If you do, those unanswered questions are recorded as
course of the calculation. Generally, you should incorrect responses.
end up with some number accompanied by a
unit. If that unit is consistent with the unit that is Entry-Level Examination
required in the answer, you are more likely to
have the correct answer. Additionally, incorpo-
Preparation
rating units into the equation improves the like- Study Hints
lihood of arriving at the correct answer.
When you use this book to prepare for the Entry-Level
Examination, establish a timetable for complete review
You are allowed three hours to complete the 160
of the material. The timetable that you establish should
questions on the NBRC Entry-Level Examination. The
be realistic. Your timetable should take your work and
score you receive is based on the percentage of correct
social schedules into consideration. Additionally, your
responses for 140 questions. The NBRC has added 20
timetable should include the time required to read and
pretest items to the 140-question examination. The 20
study the questions, analyses, and matrix designations,
pretest items are questions that have never been used.
as well as time needed to read and study appropriate
The NBRC is employing this practice to accumulate
references.
statistical data on new questions to determine their wor-
thiness of inclusion on future Entry-Level Examina- NOTE: You do not have to have all of the refer-
tions. These 20 questions are interspersed through the ences listed here. Two or three of the standard texts
examination, preventing you from identifying them. should be sufficient.

14 Introduction
 A suggested schedule for the completion of this Again, the timetable presented here is merely a sug-
study guide is shown next. Start at least six weeks be- gestion. Candidates can progress at different paces.
fore the Entry-Level Examination is scheduled. Keep in mind, however, that this examination repre-
sents a critical stage in your professional career. Suc-
Time Chapter cessful completion of this examination is essential to
your professional growth. You owe it to yourself to im-
Week 1 2. Pretest (140 items, analyses, and
references)
pose strict measures of self-discipline and to adhere to
Week 2 3. Clinical Data (250 items, analyses, and your established timetable. Good luck with your prepa-
references) ration, and good luck on the NBRC Entry-Level Exam-
ination.
Time Chapter
If you find this review book helpful in preparing you
Week 3 4. Equipment (211 items, analyses, and for the Entry-Level Examination, please consider using
references) the Advanced Practitioner Exam Review for Respira-
Week 4 5. Therapeutic Procedures (235 items, tory Care, second edition, when preparing for the Writ-
analyses, and references) ten Registry Examination.
Week 5 6. Posttest (140 items, analyses, and
references)
Week 6 Computer-Based Entry-Level Practice
Examination

Week 7 NBRC Entry-Level Examination

Introduction 15
 CHAPTER 1 TEST PREPARATION
By Helen A. Jones, RRT
A vacation is a special time for everyone. Much time is Two or three of the more comprehensive texts
spent preparing for that event, which generally occurs should be sufficient.
only once a year. Preparations usually begin months
ahead. Dates are established, a destination is chosen, a
means of travel is selected, an itinerary is generally for-
The Application
mulated, and so on. Obtain an application for the NBRC Entry-Level Ex-
Should you spend any less effort, energy, and amination from either your program director or from
time on an event—namely, the NBRC Entry-Level the NBRC. With the advent of computer-based testing
Examination—that can influence the rest of your pro- by the NBRC, only one credentialing examination ap-
fessional career? The answer should be a resounding plication is used for all of the credentialing examina-
“No!” Yet, many candidates approach the NBRC tions. So, you should be careful and follow the
Entry-Level Examination with far less preparation and application instructions meticulously.
planning than they would a long-awaited vacation. The NBRC schedules candidates on a first-come,
first-served basis. Computer-based testing is available
“ . . . failing to plan is planning to fail.” Monday through Friday. All you need to do is meet the
The purpose of this text is to help you prepare your- admission criteria and pay your fee for the appropriate
self for the NBRC Entry-Level Examination. The time examination.
you spend with this review book will help familiarize you When you are admitted for one of the computer-
with some of the key concepts that are associated with based credentialing exams, you will receive a toll-free
test preparation. This book will also give you the oppor- telephone number to schedule your examination. The
tunity to study the Entry-Level Examination Matrix, from following table outlines the relationship between the
which the credentialing examination is developed. Work- day of the week that you call the NBRC to schedule
ing within the limits of the examination matrix will pre- the Entry-Level Exam and the day of the week you will
vent you from studying unnecessary topics and wasting be scheduled for your exam, assuming that you have
valuable time. The matrix will help you focus your atten- met the admission criteria.
tion on the pertinent topics and information.
Entry-Level Exam Will
“ . . . start your preparation now!” Call NBRC On Be Administered On

Monday Thursday
When you use this book to prepare for the NBRC
Tuesday Friday
Entry-Level Examination, establish a timetable for Wednesday Monday
complete review of the material that is found in this Thursday Tuesday
book. The agenda you establish should be realistic. Friday Wednesday
Your plan should take your work and social schedules
into consideration. Additionally, your timetable should “ . . . it doesn’t pay to guess!”
include sufficient time to read and study the questions,
the analyses, and the examination matrix content, as Mailing the Application
well as the applicable references. Submit your application by certified mail. This precau-
tion ensures that you receive notification that your
NOTE: Having all the references listed in the bibli- application has been received by the NBRC and pro-
ography at the end of each chapter is unnecessary. vides you with a means to verify it was submitted.

17
Furthermore, sending your application via certified If your hospital has a protocol system, you are in a
mail affords a means of tracing the application in the position to prepare for Part D of Section I: Clinical
unlikely event it is mishandled by the United States Data. Part D of Section I: Clinical Data expects you to
Postal Service. perform the following tasks:
Your check for the examination registration fee and
a notarized copy of the certificate of completion, or • Determine the appropriateness of the respira-
diploma from the respiratory therapy program from tory care plan.
which you graduated, must be included with the appli- • Recommend modifications where indicated.
cation. Failure to include these items might cause a de- • Participate in the respiratory care plan’s devel-
lay in the application process. Such a delay could opment.
jeopardize your opportunity to take the test. If your hospital does not use a protocol system, refer
to the AARC Clinical Practice Guidelines published in
The Matrix and Clinical Respiratory Care and on the AARC Web site at www.
Practice AARC.org. They are an excellent resource. Other pub-
lished protocol articles in Respiratory Care can be re-
Throughout this review book, you are referred to the searched by using the annual indices. Practicing the
Entry-Level Examination Matrix. The matrix identifies evaluation techniques will help prepare you for the ex-
procedures and tasks that entry-level practitioners are amination and may increase your value to your facility
expected to perform upon completion of an accredited and your patients.
respiratory care education program. You should make Be sure to include time in your study for a review of
every effort to familiarize yourself with this matrix. the symptoms and physical findings that are associated
Doing so will help you focus on the pertinent aspects of with pulmonary diseases. Section I: Clinical Data of
the examination and will help you avoid reading and the Entry-Level Examination Matrix indicates that you
studying unnecessary information. will be expected to select, review, obtain, and interpret
The book’s introduction provides you with detailed data such as vital signs, chest radiographs, blood gases,
descriptions of the matrix and how to use the matrix ef- spontaneous ventilatory parameters, pulmonary func-
fectively as you prepare for this credentialing examina- tion studies, and pulse oximetry. Reviewing these pro-
tion. Do not ignore this important detail. cedures found in your reference texts would be to your
If your job responsibilities do not include any area advantage.
described in the Entry-Level Examination Matrix (e.g., While working with patients in the hospital setting,
pulmonary function testing and patient assessment), you should try to apply their cases to the information
consider arranging to spend a day or two in the appro- you have been studying to prepare for this examination.
priate clinical setting to observe and refresh your Use all your clinical experiences to supplement your
knowledge of these areas. If you work in an alternative Entry-Level Examination preparation process. Practice
care-delivery setting (e.g., home care), try to make comparing your patient assessment findings to those
arrangements for observation in a hospital environ- findings of the physician. Not only will you be prepar-
ment. Contacting the respiratory care department di- ing yourself for the examination, but you will also be
rector or the program director of a respiratory care sharpening your patient assessment and interview skills.
education program might be a place to start. Section II: Equipment deals with equipment. Part A
If you do not routinely work with ventilators, clean of Section II is concerned with selecting the appropri-
and assemble equipment, or obtain spontaneous venti- ate device and ensuring that it is clean enough for the
latory measurements, you might be at a disadvantage patient to use. A review of the procedures to clean
when trying to answer questions regarding these proce- equipment is a must. You may not be routinely involved
dures. Be creative in your approach to this area (e.g., in the process of cleaning, assembling, and ensuring
ask for more Intensive Care Unit [ICU] assignments, proper function of equipment, and you may not be well
assist ICU practitioners, observe and/or assist equip- prepared for this section. Again, make sure that you get
ment technicians in disassembling, cleaning, reassem- directly involved in the equipment cleaning and assem-
bling, and testing the ventilators). The knowledge and bling area. Texts that discuss cleaning and sterilization
experience that you gain will make this preparation techniques have been included on the reference list at
process a worthwhile investment of your time. the end of each analysis section in this book.

18 Chapter 1: Test Preparation

 Part B of Section II: Equipment is one of the more 3. The therapy performed parallels the clinical
challenging matrix areas for which to prepare. If you practice guidelines published by the AARC.
have limited clinical experience, reduced availability Again, these practices may vary from those at
to handle the equipment, and infrequent opportunities your institution. You need to answer questions
to troubleshoot equipment, you may find it difficult to based on your educational preparation, not nec-
identify and correct malfunctions of equipment. A two- essarily from your current clinical experience.
fold approach to this area is suggested: 4. Drug questions tend to be generic and test your
knowledge of their indications, contraindica-
1. Simulate malfunction situations with equipment tions, and side effects, rather than their names
you have available in your facility. (NOTE: You and classifications.
should obtain permission from your supervisor or
5. You may encounter more Intermittent Positive
department director. The author is not suggesting
Pressure Breathing (IPPB) questions than you
or advocating that equipment be purposefully de-
expect. They will include both the Bird- and
stroyed or broken for the sake of the simulation.)
Bennett-type machines.
Try to involve more experienced practitioners in
your simulation. Have them “sabotage” a piece of 6. Do not be surprised to see universal/standard
equipment for you to correct. and blood and body fluid precautions questions
included.
2. If the previous suggestion is not possible, prac-
tice with questions from this book to give you 7. Review Cardiopulmonary Resuscitation (CPR).
examples of clinical situations that you may en- Better yet, become certified in BLS, ACLS,
counter on the Entry-Level Examination. With PALS, and NRP. Do not take anything for
practice, you can develop a mental checklist to granted. Prepare completely.
evaluate and correct many malfunctions. “ . . . prepare a written study schedule.”
Questions in Parts A and B of Section II: Equipment
pertain to the same types of equipment. Section III: Study Hints
Therapeutic Procedures refers to everyday therapy.
If you find yourself struggling in any area, do not spend
This section expects you to perform the following tasks:
too much time remediating. Do not allow yourself to
• Communicate with patients and peers. repeat, repeat, and repeat. Move ahead when you can
• Protect patients from infection. answer most of the questions. You may find that less
• Perform procedures. time might be required in another area. Therefore, you
• Evaluate patients’ responses to procedures. might be able to steal some time from elsewhere.
• Modify procedures based on patients’ re- Set aside a scheduled time for study when you an-
sponses. ticipate being more alert and well rested. Analyze your
• Recommend pharmacologic agents. biological clock. Do you function better in the morn-
• Perform resuscitation procedures. ing, afternoon, or evening? Blocking out this time in
• Assist the physician and initiate and conduct your weekly schedule will help you keep your commit-
pulmonary rehabilitation and home care. ment. Choosing a location for study is also important.
Your school or local library provides a more formal en-
You should keep the following key concepts in mind vironment that is free of distractions. A desk with ade-
in the Therapeutic Procedures section: quate lighting and space can form a focal point for your
concentrated effort. Several graduates have indicated
1. Therapy as practiced at your facility may vary that they converted closet space into a study area to
from that which is recognized as a national stan- help limit distractions. The point is to make a special
dard (e.g., Synchronized Intermittent Mandatory place where you can concentrate and study effectively.
Ventilation [SIMV] may not be used for only Keep in mind that this examination represents a
weaning in your facility). critical stage in your professional career. Successful
2. The approach to patient care is generally conser- completion of this examination is essential to your pro-
vative (e.g., intubate as a last resort). The cre- fessional growth. You owe it to yourself to impose strict
dentialing examination does not advocate heroic measures of self-discipline and to adhere to your estab-
measures. lished timetable.

Chapter 1: Test Preparation 19

 “ . . . use a diagnostic test.” a cassette tape player. Kinesthetic learners may want to
be in constant motion as they study. A room that is big
The amount of time you need to prepare depends on
enough in which to pace is a must. Hands-on learners
your strengths and weaknesses. By taking the pretest in
will benefit the most from relating their studies to clin-
this book, you will be able to identify a number of con-
ical experiences in the hospital. By incorporating the
tent areas that require remediation. Remember to use
applicable learning method(s) into your study regimen,
the Pretest Entry-Level Examination Matrix Scoring
you will strengthen your ability to retain information.
Form (located immediately after each assessment sec-
Every question in this review book is supported by
tion) to identify your areas of strength and weakness.
one or more references. These references provide back-
This scoring form will also help establish a baseline
ground information for the question. More detailed in-
from which to launch your test preparation efforts. If
formation is contained in the text and is reinforced with
you have many deficiencies, more time is needed to im-
illustrations, graphs, information boxes, and so on.
prove your understanding of these weak areas. You will
To thoroughly integrate material into your mind, in-
also find an Entry-Level Examination Matrix Scoring
volve more than one method of intake. Highlighting
Form after the analyses in chapters 3, 4, 5, and 6. These
passages only involves a small portion of the brain. For
forms will assist you in evaluating your progress
example, reading activates memory that is associated
throughout your examination preparation with this re-
with the occipital region of your brain. If you write the
view book.
same information, you access a motor area of the cere-
“ . . . practice reading questions.” bral cortex. Saying the words aloud while you write
After taking the pretest, review the answers, analyze them integrates the speech area of your cerebrum with
the results, consult the matrix, and study the references. the motor and occipital regions. In other words, the
Did you miss the questions because you misread them? more parts of the brain you can involve in the process
Did you read into the questions, or did you lack famil- of information processing, the more permanent the in-
iarity with the concept underlying the questions? The formation becomes. Repetition is important to build
former can be remedied by reading more carefully. Re- what is referred to as long-term memory. The more fre-
member, careful reading is essential, but avoid “reading quently information is used, thought of, considered, re-
into the question.” The latter indicates an area that re- viewed, and so on, the more permanent and accessible
quires remediation. By categorizing the questions into it becomes.
their content areas via the Entry-Level Examination Mnemonics, acronyms, and plays on sound are all
Matrix Scoring Form located in Chapters 2–6, you can tools that help with the retention of lists, parts, or
form a prescription of study for yourself. All of the groups of symptoms. For example, the segments of the
questions have been identified by content area. You can right lung can be remembered by the saying, “Always
use this information to collate your results and pinpoint Phone Ahead, Larry May Save Mary A Lunch Plate.”
where you should focus. Be sure to complete the en- The first letter of each word represents a segment (i.e.,
closed computer-based Entry-Level Practice Exam that Anterior, Posterior, Apical, etc.). The pathological
is included in this book. changes associated with disease states, medications, or
therapy can all be recalled through the use of “triggers,”
“ . . . mind over matter.”
or memory techniques. The treatment for pulmonary
During the course of your formal education, you edema is “MOST DAMP” (i.e., morphine, oxygen,
have likely identified your learning style. Are you a vi- sympathomimetics, diuretics, albumin, mechanical
sual person who must see the words, the picture, or the ventilation, and PEEP). Your local bookstore can prob-
equipment? If so, you may find it helpful to review ably provide a list of authors who have published books
texts and look at the pictures, graphs, and other visual on memory-enhancement techniques.
aids. Do you learn best by auditory input? If so, hearing The employment of special devices, such as the
words and questions will help you learn the material. Magic Box for air:oxygen entrainment ratios1, the H
Make tapes of the questions and analyses in this book. Equation2, and the Oxyhemoglobin Dissociation
This way, you can review whenever convenient (in the Curve3 can be utilized to keep occasionally used infor-
car to and from work, for example) through the use of mation readily available.

1Scanlan, et al., Egan’s Fundamentals of Respiratory Care, 7th Ed., Mosby Year Book Publishers, St. Louis, 1999.
2Oakes, D., Respiratory Care Practitioners Pocket Guide to Respiratory Care, Health Educators Publications, Old Towne, ME, 1988.
3Pierson, D., Kacmarek, R., Foundations of Respiratory Care, Churchill Livingstone, NY, 1992.

20 Chapter 1: Test Preparation

 The use of calculators during the Entry-Level Ex- sugar level is rapid, but the pancreatic response is some-
amination is prohibited. Therefore, you must practice what prolonged. The overall effect is one of a roller-
working mathematical problems by hand. Commonly coaster—up, up, up, and then down, down, down. The
encountered calculations include the alveolar air equa- body functions best when it is in a state of homeostasis.
tion, shunt fraction, compliance, Raw, FEV1/FVC ratios, Choosing your diet carefully, however frivolous it might
and I:E ratios. Refer to these equations and others that sound, might add points to your test score.
are located for your quick reference and convenience
within the inside front cover. You may want to “dump” The Week of the
these formulas and any other information you want to
use to help answer questions as soon as possible after Examination
the start of the credentialing examination testing pe-
You are in the home stretch of your preparation. You
riod. Writing these formulas in the test booklet before
should be working on the posttest in Chapter 6 of this
taking the examination will help you be more confident
review book.
as you proceed through the test. As you encounter
questions that make reference to these formulas, you “ . . . every prize has a price.”
can turn to your prepared reference page and proceed If possible, take this week off from work. If that is
with the calculation. Double-check your work. Al- unrealistic, at least take off the day before the exam.
though the answers are multiple choice, they may in- Your supervisor and technical director should be empa-
clude selections that can be obtained when the problem thetic and cooperative—they were once in your shoes.
is approached incorrectly. Maintain the units through- Avoid working the 3 P.M.–11 P.M. shift or the 11 P.M.–
out each calculation, and cancel the units appropriately. 7 A.M. shift on the day before taking the test. You may
If you end up with the correct unit, it is likely that you undermine your own preparation efforts if you accept
also have the correct answer. or request such scheduling.
To prepare yourself physically for the test, an exer-
cise routine is suggested. Regular exercise can improve
the performance and efficiency of your cardiovascular
The Day Before the
system. Moderate exercise may also provide a great Examination
study break and refresh you for another round of ques-
tions in this book. This routine, in turn, will help in the If you live a reasonable distance from the testing center,
delivery of oxygen to the cells, and we know how fond drive there to familiarize yourself with the route and the
those brain cells are of oxygen. parking situation. If there is a parking fee, find out the
cost so that you come with enough money. Locate
“ . . . you are what you eat.” the building and the room where the test will be ad-
Your diet may influence your performance on the ministered. This groundwork will prepare you for the
test. Arriving to take the test without having had break- next morning and will lower your stress level.
fast can severely compromise your brain’s access to If you do not live near the test center, use the day be-
glucose, slow down its reaction time, and cause you to fore the exam as your travel day. Arrive at the testing
lose some of your ability to think logically. Too much center location late in the afternoon or early in the
food, however, can cause increased blood flow to the evening so you have time to have a relaxed meal and a
digestive system at the expense of the brain. Your meal good night’s rest.
on the evening before the test should include fish, a
green vegetable, salad, and no coffee or dessert. Avoid The Day of the Examination
alcoholic beverages. On the morning of the test, eat a
light breakfast that is high in complex carbohydrates Get up early enough to have time for exercise, a
(e.g., pancakes and waffles). Some nutritionists en- shower, and breakfast. If you do not exercise or shower,
courage a diet that includes fish, eggs, liver, soybeans, at least eat breakfast. Leave for the test center early
or chocolate when you are trying to assimilate large enough so that you do not have to hurry to get to the
amounts of information. The use of natural brain “neu- center. You do not want to develop any more stress than
rotransmitters” (i.e., lethicin) is controversial. is absolutely necessary. Plan to arrive at the room
So how about a candy bar? Twenty minutes after you 10–15 minutes early to locate the restrooms and vend-
eat a candy bar, your pancreas pours out insulin in re- ing machines.
sponse to the hyperglycemia. The reduction of the blood “ . . . mind over matter.”

Chapter 1: Test Preparation 21

Expect to Pass
Both success and failure are the results of habits. The
attitude and preparation tips presented in this chapter
are critical to internally accept and externally utilize the
most effective preparation for the Entry-Level Exami-
nation.
“ . . . the most valuable resource you possess
is your own ability and determination to suc-
ceed.”4
4 NBRC Horizons, Volume 16, No. 2, March 1990.

22 Chapter 1: Test Preparation

 CHAPTER 2 PRETEST

The pretest contained here is your first step toward preparing for the Entry-Level Examination. The content of the
pretest parallels that which you will encounter on the Entry-Level Examination offered by the NBRC. You will en-
counter 140 test items matching the Entry-Level Examination Matrix. The content areas included on the pretest are
as follows:

• Clinical Data (25 items)

• Equipment (36 items)
• Therapeutic Procedures (79 items)

Remember to allow yourself three (uninterrupted) hours for the pretest, and use the answer sheet located on the next
page. Score the pretest soon after you complete it. Begin reviewing the pretest analyses and references and the
NBRC matrix designations as soon as you have a reasonable block of time available.

23
 Pretest Answer Sheet
DIRECTIONS: Darken the space under the selected answer.

A B C D A B C D
1. ❏ ❏ ❏ ❏ 25. ❏ ❏ ❏ ❏
2. ❏ ❏ ❏ ❏ 26. ❏ ❏ ❏ ❏
3. ❏ ❏ ❏ ❏ 27. ❏ ❏ ❏ ❏
4. ❏ ❏ ❏ ❏ 28. ❏ ❏ ❏ ❏
5. ❏ ❏ ❏ ❏ 29. ❏ ❏ ❏ ❏
6. ❏ ❏ ❏ ❏ 30. ❏ ❏ ❏ ❏
7. ❏ ❏ ❏ ❏ 31. ❏ ❏ ❏ ❏
8. ❏ ❏ ❏ ❏ 32. ❏ ❏ ❏ ❏
9. ❏ ❏ ❏ ❏ 33. ❏ ❏ ❏ ❏
10. ❏ ❏ ❏ ❏ 34. ❏ ❏ ❏ ❏
11. ❏ ❏ ❏ ❏ 35. ❏ ❏ ❏ ❏
12. ❏ ❏ ❏ ❏ 36. ❏ ❏ ❏ ❏
13. ❏ ❏ ❏ ❏ 37. ❏ ❏ ❏ ❏
14. ❏ ❏ ❏ ❏ 38. ❏ ❏ ❏ ❏
15. ❏ ❏ ❏ ❏ 39. ❏ ❏ ❏ ❏
16. ❏ ❏ ❏ ❏ 40. ❏ ❏ ❏ ❏
17. ❏ ❏ ❏ ❏ 41. ❏ ❏ ❏ ❏
18. ❏ ❏ ❏ ❏ 42. ❏ ❏ ❏ ❏
19. ❏ ❏ ❏ ❏ 43. ❏ ❏ ❏ ❏
20. ❏ ❏ ❏ ❏ 44. ❏ ❏ ❏ ❏
21. ❏ ❏ ❏ ❏ 45. ❏ ❏ ❏ ❏
22. ❏ ❏ ❏ ❏ 46. ❏ ❏ ❏ ❏
23. ❏ ❏ ❏ ❏ 47. ❏ ❏ ❏ ❏
24. ❏ ❏ ❏ ❏ 48. ❏ ❏ ❏ ❏

24 Chapter 2: Pretest
49. ❏ ❏ ❏ ❏ 78. ❏ ❏ ❏ ❏
50. ❏ ❏ ❏ ❏ 79. ❏ ❏ ❏ ❏
51. ❏ ❏ ❏ ❏ 80. ❏ ❏ ❏ ❏
52. ❏ ❏ ❏ ❏ 81. ❏ ❏ ❏ ❏
53. ❏ ❏ ❏ ❏ 82. ❏ ❏ ❏ ❏
54. ❏ ❏ ❏ ❏ 83. ❏ ❏ ❏ ❏
55. ❏ ❏ ❏ ❏ 84. ❏ ❏ ❏ ❏
56. ❏ ❏ ❏ ❏ 85. ❏ ❏ ❏ ❏
57. ❏ ❏ ❏ ❏ 86. ❏ ❏ ❏ ❏
58. ❏ ❏ ❏ ❏ 87. ❏ ❏ ❏ ❏
59. ❏ ❏ ❏ ❏ 88. ❏ ❏ ❏ ❏
60. ❏ ❏ ❏ ❏ 89. ❏ ❏ ❏ ❏
61. ❏ ❏ ❏ ❏ 90. ❏ ❏ ❏ ❏
62. ❏ ❏ ❏ ❏ 91. ❏ ❏ ❏ ❏
63. ❏ ❏ ❏ ❏ 92. ❏ ❏ ❏ ❏
64. ❏ ❏ ❏ ❏ 93. ❏ ❏ ❏ ❏
65. ❏ ❏ ❏ ❏ 94. ❏ ❏ ❏ ❏
66. ❏ ❏ ❏ ❏ 95. ❏ ❏ ❏ ❏
67. ❏ ❏ ❏ ❏ 96. ❏ ❏ ❏ ❏
68. ❏ ❏ ❏ ❏ 97. ❏ ❏ ❏ ❏
69. ❏ ❏ ❏ ❏ 98. ❏ ❏ ❏ ❏
70. ❏ ❏ ❏ ❏ 99. ❏ ❏ ❏ ❏
71. ❏ ❏ ❏ ❏ 100. ❏ ❏ ❏ ❏
72. ❏ ❏ ❏ ❏ 101. ❏ ❏ ❏ ❏
73. ❏ ❏ ❏ ❏ 102. ❏ ❏ ❏ ❏
74. ❏ ❏ ❏ ❏ 103. ❏ ❏ ❏ ❏
75. ❏ ❏ ❏ ❏ 104. ❏ ❏ ❏ ❏
76. ❏ ❏ ❏ ❏ 105. ❏ ❏ ❏ ❏
77. ❏ ❏ ❏ ❏ 106. ❏ ❏ ❏ ❏

Chapter 2: Pretest 25
 A B C D A B C D
107. ❏ ❏ ❏ ❏ 124. ❏ ❏ ❏ ❏
108. ❏ ❏ ❏ ❏ 125. ❏ ❏ ❏ ❏
109. ❏ ❏ ❏ ❏ 126. ❏ ❏ ❏ ❏
110. ❏ ❏ ❏ ❏ 127. ❏ ❏ ❏ ❏
111. ❏ ❏ ❏ ❏ 128. ❏ ❏ ❏ ❏
112. ❏ ❏ ❏ ❏ 129. ❏ ❏ ❏ ❏
113. ❏ ❏ ❏ ❏ 130. ❏ ❏ ❏ ❏
114. ❏ ❏ ❏ ❏ 131. ❏ ❏ ❏ ❏
115. ❏ ❏ ❏ ❏ 132. ❏ ❏ ❏ ❏
116. ❏ ❏ ❏ ❏ 133. ❏ ❏ ❏ ❏
117. ❏ ❏ ❏ ❏ 134. ❏ ❏ ❏ ❏
118. ❏ ❏ ❏ ❏ 135. ❏ ❏ ❏ ❏
119. ❏ ❏ ❏ ❏ 136. ❏ ❏ ❏ ❏
120. ❏ ❏ ❏ ❏ 137. ❏ ❏ ❏ ❏
121. ❏ ❏ ❏ ❏ 138. ❏ ❏ ❏ ❏
122. ❏ ❏ ❏ ❏ 139. ❏ ❏ ❏ ❏
123. ❏ ❏ ❏ ❏ 140. ❏ ❏ ❏ ❏

26 Chapter 2: Pretest
 Pretest Assessment
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the one that is best in each case, and then blacken the corresponding space on
the answer sheet found in the front of this chapter. Good luck.

1. Compute the mean arterial pressure (MAP) for a pa- 4. Determine an appropriate flow rate needed to deliver a
tient whose blood pressure is 140/80 torr. 40-ml VT to an infant receiving mechanical ventilation
at a rate of 45 breaths/min. The desired I:E ratio is 1:2.
A. 60 torr
B. 100 torr A. 150 ml/sec.
C. 120 torr B. 126 ml/sec.
D. 140 torr C. 120 ml/sec.
D. 90 ml/sec.
2. A CRT is using the device illustrated in Figure 2-1 as
a flow meter. 5. Which of the following pathophysiological occur-
rences are amenable to oxygen therapy?

6 7 8 I. capillary shunting
5 9
4 10 II. low V̇A /Q̇ C units
3 11

2 12 III. diffusion impairments

LPM
1
0 14
13
Needle indicating IV. perfusion in excess of ventilation
15 flow rate
A. II, III, IV only
Gas outlet B. I, II only
Source gas C. II, IV only
D. III, IV only
Figure 2-1
6. A post-surgical 70-kg (IBW) patient is taken to the re-
What can be expected regarding the performance of covery room to be monitored while emerging from
this device? post-surgical anesthesia. Positive pressure volume
I. The patient will receive a flow rate less than that ventilation has been ordered. What tidal volume
indicated by the needle on the gauge. should initially be set for this 30-year-old male?
II. This type of flow meter must be operated only in A. 300 cc
an upright position. B. 500 cc
III. A helium-oxygen gas mixture would be accu- C. 700 cc
rately indicated on the flow meter. D. 1,100 cc
IV. This device becomes less accurate as the pressure
in the compressed gas cylinder decreases. 7. An 85-kg mechanically ventilated, adult male is orally
A. I only intubated with a 7.0 mm I.D. endotracheal tube. The
B. II, III only CRT fills the cuff with air just until the airway is
C. IV only sealed. A cuff pressure manometer indicates an in-
D. I, II only tracuff pressure of 60 mm Hg. Why is the intracuff
pressure so high?
3. A patient with a cuffed tracheostomy tube is receiving A. The endotracheal tube is too small for this patient’s
IPPB via a Bennett PR-2 with pressures of 25–30 cm airway.
H2O. The ventilator will not cycle to exhalation. There B. The patient has excessive tracheobronchial secre-
is no leak around the cuff, and all the circuit connec- tions.
tions are tight. The most likely solution to this problem C. The patient is likely experiencing bronchospasm.
is to D. The one-way valve associated with the pilot bal-
A. increase the peak flow rate. loon is malfunctioning.
B. lower the peak pressure.
C. inject more air to the cuff. 8. A 32-year-old asthmatic female with 10 years’ experi-
D. activate the terminal flow control. ence using a metered dose inhaler (MDI) experiences

Chapter 2: Pretest 27
 little relief after usage for control of an acute episode. 12. A nebulizer delivering 40% oxygen via a Briggs adap-
The patient indicated that she did not feel like she was tor attached to a tracheotomized patient is operating at
getting any medication. The MDI is kept in her purse 8 L/min. With each patient inspiration, the aerosol
for availability and worked properly earlier in the day. completely disappears from the reservoir tubing at-
The MDI was placed in water and the patient noticed tached to the distal outlet of the Briggs adaptor. What
that it was partially submerged with the nozzle end should the CRT do at this time?
down. What is the most likely cause of this situation?
A. Increase the flow rate from the nebulizer.
A. The MDI is empty. B. Add one to two lengths of aerosol tubing at the
B. A foreign object may be occluding the mouth- outlet of the Briggs adaptor.
piece. C. Do nothing, because it is normal for the aerosol to
C. The MDI may not have been shaken prior to disappear with each inspiration.
activation. D. Instruct the patient to inhale more slowly.
D. The actuator orifice should be cleaned.
13. While reviewing the radiographic findings contained
9. In the process of examining the chest radiograph of a in a patient’s chart, the CRT notices that the latest
patient, the CRT notices the right lung to be hyperlu- chest radiograph results read as follows:
cent. Which of the following physical findings would
the CRT likely obtain from the right side of this pa- “. . . complete opacification of the right thorax, ac-
tient’s chest? companied by a leftward mediastinal shift and tracheal
deviation. . .”
I. a dull percussion note
II. crepitations
How should these findings be interpreted?
III. absent or diminished breath sounds
IV. reduced tactile fremitus A. The patient is experiencing atelectasis of the right
lung.
A. III, IV only
B. The patient has a right-sided pneumothorax.
B. I, II only
C. The patient has a right-sided pleural effusion.
C. I, III only
D. The patient has bilateral interstitial lung disease.
D. I, III, IV only
14. The CRT is administering a beta-2 agonist to a chronic
10. While monitoring a patient receiving mechanical ven-
obstructive pulmonary disease (COPD) patient who
tilation, the CRT has determined that auto-PEEP is
has a reversible component to her obstructive airway
present. Which of the following ventilator adjustments
disease. The patient is tense and anxious during the
can she make to rectify this situation?
treatment. How should the CRT instruct her to breathe
I. Increase the ventilatory rate. optimally during this treatment?
II. Lengthen the expiratory time.
A. The patient should be allowed to assume a pattern
III. Shorten the inspiratory time.
suitable to herself.
IV. Increase the tidal volume.
B. The patient should inhale slowly and deeply, per-
A. I, IV only form an inspiratory pause, and exhale passively
B. II, III only through pursed lips.
C. II, III, IV only C. The patient should inhale slowly and deeply, per-
D. II, IV only form an inspiratory pause, and exhale rapidly.
D. The patient should be instructed to breathe normally.
11. Which of the following disease states would be typi-
fied by having an FEV1/FVC ratio of less than 0.75? 15. Which of the following medications would be appro-
priate for the treatment of an asthmatic patient who ex-
I. sarcoidosis
hibits daily symptoms of the disease?
II. chronic bronchitis
III. emphysema I. inhaled corticosteroids
IV. ascites II. inhaled beta-2 agonists
III. oral theophylline
A. I only
B. II, III only A. I, II, III
C. I, III only B. I only
D. I, II, III, IV C. II, III only
D. I, II only

28 Chapter 2: Pretest
16. During the administration of an aerosolized adrenergic Table 2-1: PEEP Trial Performed at FIO2 0.60
bronchodilator, the patient’s pulse increases from 88
Blood Heart Rate
beats/min. to 115 beats/min. What action should the
PEEP CL C.O. Pressure (beats/ PaO2
CRT take?
(cm H2O) (ml/cm H2O) (L/min) (torr) minute) (torr)
A. Stop the treatment and notify the physician.
0 25 4.20 130/60 115 55
B. Change the medication to normal saline.
5 29 4.90 135/70 111 59
C. Stop the treatment and put the patient in a reverse
8 35 5.30 135/75 106 69
Trendelenburg position. 10 28 4.80 120/65 112 60
D. Continue the treatment while monitoring the patient.

17. A CRT is performing a maximum inspiratory pressure Based on these findings, what should the CRT recom-
(MIP) measurement on a patient. The patient is agi- mend?
tated, and the CRT cannot get a negative pressure read-
ing. The setup is illustrated in Figure 2-2. A. Reduce the FIO2 to 0.60.
B. Institute PEEP.
C. Institute pressure-support ventilation.
D. Institute inverse-ratio ventilation.
Manometer
cm H2O 19. A 25-year-old male with a history of asthma has been
mechanically ventilated for 10 days. His secretions are
Thumb port
One-way valve thick, yellow, and difficult to suction. There is evidence
(covered)
of pulmonary infiltrates seen on a chest X-ray. To aid in
the removal of the secretions, what suggestions should
the CRT make to the physician?
Patient's endotracheal tube I. Aerosolize 20% Mucomyst.
II. Lavage with normal saline.
III. Administer 20% Mucomyst with a bronchodilator
via a micronebulizer.
Figure 2-2: Maximum inspiratory pressure meter IV. Administer albuterol via a micronebulizer.
V. Administer racemic epinephrine via a micronebu-
Which of the following statements is most appropriate? lizer.

A. The direction of the one-way valve should be A. I, V only

reversed. B. II, III only
B. The CRT is using the wrong type of manometer. C. II, IV only
C. The CRT should reassure the patient and continue D. II, V only
the test.
D. The thumb port should not be covered during this 20. The CRT has measured the intracuff pressure of a tra-
measurement. cheostomy tube inserted in a mechanically ventilated
patient to be 33 torr. What action should the CRT take
18. While reviewing the chart of a mechanically ventilated at this time?
patient, the CRT notices that a PEEP trial was con- A. No action is necessary, because this pressure is
ducted when the patient was receiving an FIO2 of 0.60. acceptable.
The current ventilator settings are listed below. B. The pressure manometer needs to be calibrated.
mode: control C. Air needs to be aspirated out of the cuff.
tidal volume: 900 ml D. Air needs to be injected into the cuff.
ventilatory rate: 12 breaths/min.
FIO2: 0.70 21. A patient who has a tracheostomy needs oxygen ther-
PEEP: 0 cm H2O apy. Which of the following oxygen-delivery devices
would be most appropriate?
Arterial blood gas data at these settings reveal:
A. aerosol mask
PO2 55 torr; PCO2 46 torr; pH 7.34 B. face tent
The PEEP study being reviewed by the CRT is shown C. tracheostomy collar
in Table 2-1. D. air entrainment mask

Chapter 2: Pretest 29
22. A patient receiving controlled mechanical ventilation 26. During percussion of the chest wall, a crackling sound
via a volume-cycled ventilator has experienced a de- and sensation are noted. Which of the following con-
creased pulmonary compliance. Which response would ditions do these findings suggest?
likely occur?
A. The patient has excess secretions.
A. a minute ventilation decrease B. Subcutaneous emphysema is present.
B. a decrease in the delivered tidal volume C. The patient has pneumonia.
C. an increase in the flow rate D. A tumor is present in the area of the lung in which
D. an increase in the peak inspiratory pressure (PIP) the sounds are heard.

23. Which of the following actions would be helpful to 27. When a patient’s trachea is being intubated using a
teach an asthmatic the proper technique of using an Macintosh laryngoscope blade, where should the
MDI? blade be positioned for exposing the glottis?
I. Have the patient verbalize the factors that make A. under the epiglottis
asthma worse. B. either above or below the epiglottis
II. Give the patient written instructions. C. against the roof of the mouth
III. Demonstrate the procedure. D. into the vallecula
IV. Ask the patient why using a peak flow meter is
important. 28. Aerosol therapy via ultrasonic nebulization has been
ordered for the purpose of sputum induction. The pa-
A. I, IV only
tient has thick, copious secretions with frequent mu-
B. II, III only
cous plugging. Given that the patient is also asthmatic,
C. I, II, III only
what modification of the order should the CRT recom-
D. I, II, III, IV
mend?
24. The CRT has obtained the following ABG and acid- I. Discontinue the ultrasonic order.
base data on a 57-kg patient who has just been suc- II. Add Mucomyst to the ultrasonic nebulizer.
cessfully resuscitated and is now being mechanically III. Add a bronchodilator to the ultrasonic nebulizer.
ventilated. IV. Use a small-volume nebulizer with a bronchodila-
tor and Mucomyst.
PO2 74 mm Hg
PCO2 48 mm Hg A. III only
pH 7.53 B. II only
HCO 3̄ 14 mEq/liter C. I, IV only
B.E. –12 mEq/liter D. I only

What recommendation should the CRT make? 29. A CRT inspects the bulk oxygen system near the con-
struction site of a new hospital. He notices that the va-
A. Administer two ampules of sodium bicarbonate.
porizer is arranged in columns and is supplied with
B. Increase the ventilatory rate.
heat from an indirect source. What should he recom-
C. Increase the FIO2.
mend to his supervisor?
D. Repeat the ABG analysis using a different blood
gas analyzer. A. that the vaporizer should not be arranged in
columns
25. The CRT observes a patient “fighting the ventilator.” B. that a direct heat source must be installed
Which of the following conditions might account for C. that the vaporizer must be electrically grounded
this situation? D. that the National Fire Protection Agency specifi-
cations appear to be in compliance
I. increased flow rate
II. insensitive demand valves
30. Where on an adult victim’s sternum should a rescuer’s
III. decreased inspiratory time
hands be positioned for external cardiac massage?
IV. patient irritability and agitation
A. lower half of the sternum
A. I, II, III, IV
B. middle third of the sternum
B. I, III only
C. upper half of the sternum
C. II, IV only
D. lower third of the sternum
D. I, II, IV only

30 Chapter 2: Pretest
31. A patient, wearing a full face mask while receiving non- C.
invasive positive pressure ventilation (NPPV) for venti-
latory failure caused by pneumonia, is experiencing +

PRESSURE
difficulty swallowing. Which of the following actions

(cm H2O)
would be most suitable for the CRT to take at this time?
0
A. Apply NPPV using a nasal mask.
B. Fit the patient with a larger-size full face mask.
–
C. Monitor the patient closely to avoid aspiration.
D. Intubate and mechanically ventilate the patient. TIME (sec)
Figure 2-3c:
32. During the administration of an IPPB treatment, the
patient complains of dizziness and paresthesia. The
CRT’s response should be to D.
A. instruct the patient to perform an inspiratory pause.
+

PRESSURE
B. encourage the patient to cough.

(cm H2O)
C. coach the patient to breathe more slowly.
D. instruct the patient to breathe rapidly and deeply. 0

33. A patient with supraventricular tachycardia is receiv-

–
ing advanced cardiac life support. The physician in-
tends to cardiovert the patient and asks the CRT when TIME (sec)
is the appropriate time during the cardiac cycle to ap-
ply the cardioversion. The CRT should respond by Figure 2-3d:
saying that cardioversion must be applied during the
35. The results of three valid measurements of the FVC
A. R wave. from the same subject are listed in Table 2-2.
B. QRS complex.
C. C wave. Table 2-2
D. P-R interval.
FEF25%–75%
Trial FVC (liters) FEV1 (liters) (L/sec.)
34. Which pressure-time tracing (Figures 2-3a-d) repre-
sents intermittent mandatory ventilation (IMV)? 1 4.40 3.10 2.46
2 4.20 3.60 2.56
3 4.50 3.45 2.70
A.

+ If the predicted normal FEV1 for this subject is 4.20

PRESSURE
(cm H2O)

liters, what is the percent predicted FEV1?

0 A. 74%
B. 81%
– C. 86%
D. 100%
TIME (sec)
Figure 2-3a: 36. Which of the following actions should be taken by the
CRT in an effort to decrease the aerosol output of a jet
B. nebulizer?
A. Decrease the FIO2 setting.
+
B. Shorten the tubing.
PRESSURE
(cm H2O)

C. Heat the aerosol.

0 D. Decrease the flow rate of the gas.

37. Although aggressive chest physiotherapy (CPT) is ef-

–
fective in mobilizing secretions, the patient, who is in
TIME (sec) end-stage COPD, finds the treatment extremely un-
pleasant. Who should ultimately decide whether to
Figure 2-3b: continue aggressive therapy in this case?

Chapter 2: Pretest 31
 A. the medical team C. Administer metaproterenol sulfate via a small-
B. the primary physician volume nebulizer.
C. the patient’s family D. Have the patient perform incentive spirometry
D. the patient and coughing maneuvers.

38. Which of the following oxygen-delivery devices is/are 42. Which of the following statements represent potential
most suitable in the home setting for extending the use hazards associated with the use of an oropharyngeal
of a portable liquid-oxygen unit? airway that is too large for the patient?

I. a mask with a reservoir I. This use may result in laryngeal obstruction.

II. a pendant reservoir cannula II. Tracheobronchial aspiration may occur.
III. a Briggs adaptor with 100 cc of reservoir tubing III. Gastric insufflation may result.
IV. a nasal catheter IV. Effective ventilation may be prevented.

A. II only A. I, II, III, IV

B. III only B. I, III, IV only
C. II, III only C. II, III only
D. I, IV only D. I, IV only

43. A COPD patient is being mechanically ventilated with

39. An MDI is being used to administer medication to a the following settings:
mechanically ventilated patient through a ventilator
MDI adaptor. When should the CRT actuate the MDI • mode: assist-control
to provide the most effective aerosol deposition? • tidal volume: 900 ml
• ventilatory rate: 10 breaths/min.
A. immediately prior to a mechanical breath • FIO2: 0.30
B. immediately after the beginning of a mechanical • I:E ratio: 1:2
breath • PEEP: 3 cm H2O
C. during the midportion of a mechanical breath • peak inspiratory flow rate: 30 L/min.
D. anytime during the ventilatory cycle
What ventilator setting change should the CRT recom-
mend?
40. Ventilatory data obtained from a spontaneously breath-
ing patient are shown as follows. A. increasing the FIO2
B. decreasing the I:E ratio
tidal volume: 500 ml
C. increasing the tidal volume
ventilatory rate: 12 breaths/min.
D. increasing the set rate
I:E ratio: 1:2
inspiratory time: 1 second 44. The accuracy of pulse oximeters can be affected by
Which of the following Venturi mask adaptors would I. patient motion.
provide a sufficient inspiratory flow to meet this pa- II. the intensity of the light transmission.
tient’s demands if the source flow is 3 L/min.? III. decreased perfusion.
A. 28% adaptor IV. bright ambient lights.
B. 30% adaptor A. I, II, III only
C. 34% adaptor B. I, III, IV only
D. 36% adaptor C. II, III, IV only
D. I, II, III, IV
41. The CRT is summoned to evaluate a 24-hour, post-op,
thoracotomy patient. The patient complains of severe 45. An infant who is being supported with nasal continu-
pain in the incisional area and difficulty obtaining a ous positive airway pressure (CPAP) with prongs sud-
deep breath. Upon auscultation of the patient’s chest, it denly displays a decreased SpO2. The nurse indicates
is determined that the patient’s breath sounds are bi- that otherwise the infant is stable and suggests a prob-
laterally diminished. Which mode of therapy would be lem with the equipment. What is the most likely cause
appropriate for the CRT to recommend at this time? for this clinical deterioration?
A. No therapy is needed—her breath sounds are di- A. dislodgment of the prongs from the infant’s nose
minished because of pain. B. water in the circuit
B. Administer IPPB, followed by CPT. C. separation of the prongs from the nasal block
D. pressure on the back of the neck from the strap

32 Chapter 2: Pretest
46. What should the CRT do after performing an arterial He notices that the valve does not seem to be moving
puncture for blood gas analysis? normally, and the patient is not being allowed to ex-
hale. The best course of action is to:
A. Perform the Allen test to verify collateral circula-
tion. A. obtain another resuscitation bag.
B. Apply a pressure bandage over the wound. B. disconnect the patient periodically to allow exha-
C. Pressurize the puncture site for a minimum of five lation.
minutes. C. decrease the rate of ventilation to allow more time
D. Hand warm the sample to mix the anticoagulant. for exhalation.
D. reduce the gas flow to about 15 L/min.
47. While administering an IPPB treatment to a patient, the
CRT notices the indicator needle on the pressure 52. A 65-kg patient is receiving mechanical ventilation.
manometer deflecting from 0 cm H20 to –2 cm H2O as His ventilator settings are as follows:
the patient inspires. What should the CRT do at this time?
• mode: assist–control
A. Do nothing and continue with the treatment. • tidal volume: 900 ml
B. Adjust the sensitivity control to allow the machine • FIO2: 1.0
to cycle on more easily. • ventilatory rate: 10 breaths/min.
C. Reduce the preset pressure to a level more tolera-
His ABG data reveal:
ble for the patient.
D. Interrupt the treatment to encourage the patient to PO2 45 torr
relax. HCO 3̄ 26 mEq/liter
PCO2 33 torr
48. If the flow rate were to be decreased on a pressure pre- SO2 86%
set ventilator, while all the other settings remained the pH 7.52
same, what would be the result?
What should the CRT recommend for this patient at
A. The delivered tidal volume would increase. this time?
B. The ventilatory rate would increase.
A. initiating control mode ventilation
C. The inspiratory time would decrease.
B. instituting 5 cm H2O PEEP
D. The inspiratory pressure would increase.
C. nebulizing a bronchodilator in-line
D. increasing the patient’s tidal volume
49. A patient should be checked for orientation to
___________ as a first step in assessing mental status.
53. Which of the following blood-pressure measurements
I. time would possibly cause difficulty in palpating a periph-
II. place eral pulse?
III. person
A. 90/60 mm Hg
A. I, III only B. 100/80 mm Hg
B. II, III only C. 120/60 mm Hg
C. I, II only D. 150/80 mm Hg
D. I, II, III only
54. A patient is being maintained on a continuous-flow,
50. A 93-year-old blind female is recovering from a bro- mask CPAP system. Which of the following alarms is
ken hip. She assures the CRT that she has been blow- the most important to ensure maintenance of therapy?
ing into her incentive spirometer every hour, as
A. high FIO2
instructed. The most appropriate action for the CRT to
B. low pressure
take would be to
C. high ventilatory rate
A. recommend CPT. D. low minute volume
B. discontinue incentive spirometry.
C. review the instructions with the patient. 55. What is the purpose of the device pictured in Figure 2-4?
D. recommend blow bottles. A. to increase the FIO2
B. to maintain a stable FIO2
51. A CRT is ventilating an intubated patient with a man- C. to nebulize medication
ual resuscitator. The oxygen flow meter is set at flush. D. to conserve oxygen

Chapter 2: Pretest 33
 C. Call for a replacement ventilator, because the cau-
tion light indicates that the ventilator will soon be-
come inoperative.
D. Call the manufacturer for suggestions, because
this situation is highly unusual.

58. A patient has just returned from surgery where she had
a septoplasty procedure performed. The surgeon has
ordered a large-volume nebulizer for humidification of
secretions. When the CRT attempted to apply the
aerosol mask to the patient’s face, the patient refused
to allow the mask to touch her nose. What recommen-
dations should the CRT suggest to make this patient
comfortable with her therapy?
A. Place the patient in a croupette.
B. Orally intubate the patient.
C. Replace the aerosol mask with a face tent.
D. Sedate the patient to make her more comfortable.
Source gas
59. Under what circumstances would a pulse oximeter pro-
Figure 2-4
vide a poor indication of oxygen delivery to body tissues?
56. While resuscitating an unresponsive, pulseless patient, A. when a patient has a hemoglobin concentration of
the CRT notices the ECG pattern in Figure 7 g/dl
2-5 appear on the monitor. What action should be B. when a patient has a PaO2 in excess of 100 mm Hg
taken at this time? C. when a patient has a bilirubin level of 6 mg/dl
D. when a patient is hyperthermic
A. Administer 1.0 to 1.5 mg/kg of lidocaine I.V. push.
B. Defibrillate with 200 joules. 60. A patient with congestive left-ventricular failure has
C. Administer 1 mg of epinephrine I.V. push. developed a severe bilateral pneumonia that will re-
D. Intubate the patient. quire endotracheal (ET) intubation. The CRT has been
attempting to insert an ET tube for about 45 seconds,
57. The audible alarm on a microprocessor ventilator and the patient shows increased respiratory distress.
sounds while the CRT is outside the immediate area. What should the CRT do at this time?
When the CRT arrives, there is no alarm. The orange A. Halt the intubation procedure and oxygenate the
caution light is illuminated, however, as are the high- patient for at least three minutes.
pressure limit, the I:E, and the high-ventilatory rate B. Stop the intubation procedure, have the patient sit
alarms. The patient seems free of distress. What should up, and oxygenate the patient for four minutes.
the CRT do at this time? C. Interrupt the intubation procedure, suction the pa-
A. Disconnect the patient from the ventilator, begin tient, and oxygenate him for at least three minutes.
manual ventilation, and call for assistance. D. Continue with the intubation procedure while
B. Auscultate the patient, suction if necessary, and holding open-ended oxygen tubing with a flow of
reset the alarms. 5 L/min. near the patient’s mouth.

Figure 2-5: ECG pattern of an unresponsive, pulseless patient who is monitored

34 Chapter 2: Pretest
61. A patient is being evaluated for weaning from me- 65. While performing ventilator rounds in the ICU, the CRT
chanical ventilation. Which of the following criteria hears the high-pressure alarm continuously sounding
indicate that the patient may be ready for weaning? and gurgling noises coming from the airway of one the
ventilator patients. What should she do at this time?
I. a P(A-a)O2 gradient of 380 mm Hg after breath-
ing 100% oxygen A. Administer an in-line bronchodilator.
II. a vital capacity of 30 ml/kg B. Instill 5 cc of normal saline into the patient’s air-
III. a VD/VT of 0.65 way.
IV. a maximum inspiratory pressure of –38 cm H2O C. Perform tracheobronchial suctioning.
D. Recommend that a STAT chest X-ray be obtained.
A. II, III only
B. I, IV only
66. Which of the following ventilator modes could be se-
C. I, II, IV only
lected when it is desirable to maintain respiratory mus-
D. II, IV only
cle strength?
62. A patient has been intubated with an 8.0 mm I.D. oral I. IMV mode
ET tube. The patient develops coarse breath sounds, II. assist–control mode
and there are visible secretions in the ET tube. The III. synchronized IMV mode
CRT, using a 16 Fr suction catheter, begins to clear the IV. control mode
tube after appropriately preoxygenating the patient.
A. I, II only
The patient now develops tachycardia and desaturation
B. I, III only
as determined by a pulse oximeter. What can the CRT
C. I, II, III only
do to try to prevent these developments?
D. III, IV only
A. Wait to suction the patient until the procedure is
indicated. 67. The CRT is summoned to the emergency department
B. Increase the amount of negative pressure applied to see a patient in respiratory distress. Upon arrival, the
to –150 mm Hg. CRT notices that the patient has deep, rapid respira-
C. Turn off the pulse oximeter to prevent an alarm tions, a ventilatory pattern known as Kussmaul’s
from sounding. breathing. Which of the following acid-base imbal-
D. Use a 12 Fr suction catheter. ances is this patient likely experiencing at this time?
A. metabolic alkalosis
63. A family member seated at the bedside of a 24-year- B. respiratory acidosis
old motor vehicle accident patient asks the CRT to C. respiratory alkalosis
look at the humidification system. The CRT notes that D. metabolic acidosis
the Briggs adaptor attached to the tracheostomy tube
appears to be tugging on the tracheostomy tube. The 68. A patient should be instructed to breathe according to
patient moves about frequently and is active, but not which of the following patterns when performing a
alert. What modification should the CRT suggest? slow vital capacity maneuver?
A. No change is necessary, because this situation is A. Inhale slowly and sustain the inspiratory effort for
normal. three seconds.
B. Apply restraints to the patient. B. Inhale as much as possible, followed by a fast,
C. Add more aerosol tubing. complete expiration.
D. Replace the Briggs adaptor with a tracheostomy C. Exhale completely and slowly, following a maxi-
collar. mum inspiration.
D. Exhale forcefully and completely, following a
64. Which of the following problems might cause an in- three-second inspiratory hold.
crease in peak inspiratory pressure on a ventilator at-
tached to a patient with a tracheostomy tube? 69. A 65-year-old man is presented to the emergency room
I. mucous plugging with shortness of breath and a chief complaint of se-
II. herniation of the cuff over the tube tip vere chest pain. He has always been in good health. He
III. cuff leakage does not take any medications and has not seen a
IV. biting of the tube physician for years. He reports being tired during the
past week and having intermittent chest discomfort
A. I only with exertion over the last 2 days. The physician orders
B. I, II only aspirin, an ECG, and 2 L/min. of nasal oxygen. Which
C. I, IV only of the following benefits of oxygen therapy are in-
D. I, II, III, IV tended for this patient?

Chapter 2: Pretest 35
 I. reduction of the work of breathing The patient’s blood pressure and heart rate are 145/85
II. reduction of the cardiopulmonary workload torr and 100 beats/min., respectively. What should the
III. correction of arterial hypoxemia CRT do at this time?
IV. prevention of absorption atelectasis
A. Continue the weaning process and monitor the
A. I, II only patient.
B. II, III only B. Increase the FIO2 to 0.60.
C. I, II, III only C. Increase the mandatory volume to 0.80 liter.
D. II, III, IV only D. Increase the mechanical ventilatory rate to 8
breaths/min.
70. Which of the following findings or patient complaints
could indicate a possible decreased diaphragmatic 72. A mist tent at 40% oxygen has been ordered for a five-
function or paralysis? year-old cystic fibrosis patient. While performing oxy-
gen rounds, the CRT notices that the tent has a large
I. inward movement of the abdomen on inspiration
hole cut out on the top and that the flow meter is set at
II. shortness of breath when lying supine
8 L/min. What should she do at this time?
III. intercostal or subcostal retractions
IV. decreased maximal inspiratory pressure A. Nothing needs to be done, because this device is
set up and is functioning properly.
A. II, III only
B. She should use a closed-top tent with an oxygen
B. I, III, IV only
flow rate of 15 L/min.
C. I, II, IV only
C. She should increase the flow meter setting to 15
D. I, IV only
L/min.
D. She should request that a large oxyhood be used.
71. An oriented, post-flail chest patient weighing 185 lbs
(ideal body weight [IBW]) is being weaned from 73. After applying percussion and postural drainage to a
SIMV. His ventilator settings before the weaning patient’s lower lobes, the CRT hears increased aeration
process were: and a decrease in rhonchi over the posterior chest. What
• SIMV rate: 10 breaths/min. do these findings indicate in reference to the CPT?
• mechanical tidal volume: 850 cc A. The therapy is effective and should be continued.
• FIO2: 0.40 B. These findings represent an adverse response to
His new ventilator settings and spontaneous ventila- the treatment.
tory measurements are as follows: C. The therapy is ineffective and should be discon-
tinued.
• SIMV rate: 6 breaths/min. D. An aerosolized bronchodilator should be added to
• spontaneous ventilatory rate: 18 breaths/min. the regimen.
• spontaneous tidal volume: 400 cc
• mechanical tidal volume: 850 cc 74. A patient on whom CPR has just been performed has
• FIO2: 0.40 the following blood gas values for a sample obtained
This patient’s ABG and cardiovascular data are shown from the femoral area:
here: PO2 55 torr; PCO2 47 torr; pH 7.33
• PO2 70 torr An ear oximeter, however, indicates an SpO2 of 93%.
• PCO2 33 torr The patient’s blood pressure and pulse are 130/80 torr
• pH 7.48 and 75 beats/min, respectively. What should the CRT
• HCO 3̄ 24 mEq/liter recommend at this time?
• BP 130/80 torr
A. obtaining another blood gas sample
• heart rate 85 beats/min.
B. administering bicarbonate
After 15 minutes on the ventilator settings indicated C. increasing the tidal volume delivered by the man-
previously, the CRT evaluates the patient and notes the ual resuscitator
following findings: D. resuming external cardiac compressions
• spontaneous ventilatory rate: 26 breaths/min.
75. The CRT is monitoring the intracuff pressure of a tra-
• spontaneous tidal volume: 350 cc
cheostomy tube inserted in a patient receiving mechani-
cal ventilation. She observes the pressure manometer
An ABG obtained at this time indicates:
indicating a pressure of 42 cm H2O. What should she do
PO2 68 torr; PCO2 46 torr; pH 7.32; HCO 3̄ 23 mEq/liter at this time?

36 Chapter 2: Pretest
 A. Inject more air through the pilot balloon. liters but is still complaining of abdominal pain around
B. Release some of the air from the cuff. the incision site during the IS procedure. Which of the
C. Insert a new tracheostomy tube. following recommendations should the CRT make?
D. Do nothing because the cuff pressure reading is
A. Discontinue the IS.
acceptable.
B. Replace the IS treatments with IPPB therapy.
C. Terminate the IS treatments and institute CPT.
76. A 28-year-old male diagnosed with Guillain–Barré has
D. Continue the IS treatments and monitor the patient.
recently been intubated secondary to deteriorating vi-
tal capacity measurements. The physician has ordered 81. Which of the following levels of consciousness is
a lateral-rotational bed and suctioning every 2 hours. characterized by the patient being confused, easily ag-
Breath sounds are clear bilaterally but diminished at itated, irritable, and hallucinatory?
the bases, and attempts at suctioning yield scant white
secretions. The CRT should recommend A. confused
B. delirious
A. placement of the patient on a Stryker frame. C. lethargic
B. initiation of CPT every hour. D. comatose
C. changing the order to suctioning PRN.
D. changing to a closed-system, directional-tip, suc- 82. What is the minimum flow rate that could be set on the
tion catheter. flow meter to provide an adequate flow to a patient
breathing via a 28% air-entrainment mask? The pa-
77. What is the significance of a pulmonary function test tient’s ventilatory status is indicated below.
that reveals an FEV1 equal to the FVC? (Assume a
valid test.) • ventilatory rate (f): 20 breaths/min.
• inspiratory time (TI): 1 sec.
A. mild obstructive • expiratory time (TE): 2 sec.
B. mild restrictive • tidal volume (VT): 500 ml
C. severe restriction
D. severe obstruction A. 2 L/min.
B. 3 L/min.
78. Which of the following devices could be used to con- C. 4 L/min.
firm the accuracy of an aneroid manometer? D. 5 L/min.
A. mercury sphygmomanometer 83. A patient brought into the emergency department has
B. supersyringe an oropharyngeal airway in place. The emergency
C. precision Thorpe tube medical technician (EMT) explains that the patient has
D. hygrometer significant (nearly complete) airway obstruction with-
out the artificial airway. Although not completely con-
79. The CRT has just completed administering an scious, the patient begins to gag. What should the CRT
aerosolized albuterol treatment to an asthmatic patient do to maintain the patient’s airway?
in the emergency department. If this patient experi-
ences side effects from this medication, which of the A. Remove the oropharyngeal airway and turn the
following side effects would likely develop? patient on his side.
B. Leave the oropharyngeal airway in place, because
I. palpitations the patient will be able to tolerate it shortly.
II. drowsiness C. Leave the oropharyngeal airway in place and be
III. tachycardia ready to suction should the patient vomit.
IV. tachypnea D. Replace the oropharyngeal airway with a naso-
A. II, IV only pharyngeal airway.
B. I, III only
C. I, III, IV only 84. An elderly 48-kg, severe COPD patient is receiving
D. I, II, III, IV mechanical ventilation for acute respiratory failure.
Her ventilator settings include:
80. An afebrile, postoperative, abdominal surgery patient is • mode: assist–control
receiving incentive spirometry (IS). The patient’s pre- • ventilatory rate: 12 breaths/min.
operative volume was 3.5 liters (10% of predicted). Two • peak inspiratory flow rate: 30 L/min.
days after surgery, the patient has not achieved 3.5 liters. • tidal volume: 500 cc
The patient has achieved a postoperative volume of 2.1 • FIO2: 0.40

Chapter 2: Pretest 37
 The CRT notes that the patient cycles on the ventilator 88. A patient is receiving mechanical ventilation with a
24 breaths/min. The patient’s work of breathing pressure-cycled ventilator. The patient suddenly devel-
(WOB) appears to be increasing. The physician asks ops bronchospasm. What influences will this patho-
for the CRT’s recommendation but indicates that he logic change have on the mechanical ventilator?
does not want to change the ventilatory mode at this
I. The ventilator will terminate inspiration earlier.
time. The CRT should recommend
II. A reduced tidal volume will be delivered.
A. decreasing the flow rate to decrease the inspira- III. The inspiratory time will increase.
tory time. IV. The inspiratory flow rate will decrease.
B. increasing the tidal volume to decrease the inspi-
A. I, II only
ratory time.
B. I, IV only
C. increasing the flow rate to decrease the inspiratory
C. II, III, IV only
time.
D. I, II, IV only
D. increasing the ventilatory rate to lengthen the ex-
piratory time.
89. An elderly patient in an extended-care facility has de-
veloped an aspiration pneumonia, with radiographic
85. Results of four hours of respiratory monitoring of a pa-
documentation of pulmonary atelectasis presumed to
tient breathing oxygen via a nasal cannula indicate that
be associated with secretion retention. The patient has
expiratory time and airway resistance have increased.
a weak, ineffective cough, and attempts at suctioning
What scenario would be consistent with these trends?
have yielded scant amounts of thick, tenacious secre-
A. The patient has switched from nasal ventilation to tions. All of the following modifications could be done
oral ventilation. to improve the clearance of secretions EXCEPT:
B. The patient has hyperactive airways and de-
A. increasing the duration of application of suction
creased forced expiratory flow rates.
to 20 seconds
C. The patient has been sleeping.
B. instilling sterile normal saline for irrigation
D. The patient has been swallowing the oxygen gas
C. ensuring correct positioning of the patient
flow and has developed severe gastric distention.
D. increasing the frequency of suctioning
86. A patient who has disseminated intravascular coagu-
90. A pneumatically powered, pressure-cycled ventilator
lopathy is about to undergo fiberoptic bronchoscopy
would be most appropriate to use for ventilatory sup-
for a lung biopsy. What types of tests or measurements
port for which of the following patients?
need to be performed or obtained before the bron-
choscopy is performed? A. five-year-old patient with status asthmaticus
B. 18-year-old patient suffering from narcotic over-
I. an activated partial thromboplastin time
dose
II. a prothrombin time
C. 20-year-old patient with bilateral pulmonary con-
III. a complete blood count
tusions
IV. a bleeding time
D. 66-year-old patient with bullous emphysema
A. I, IV only
B. II, III only 91. A patient is receiving oxygen therapy via a simple
C. I, II, IV only mask operated at a flow rate of 15 L/min. The CRT ob-
D. I, II, III, IV serves this patient having a nonproductive cough. Ad-
ditionally, the patient is complaining of a dry mouth,
87. Which patient conditions would be compatible with nose, and throat. What should the CRT do at this time?
the use of nasal CPAP?
I. Check the humidifier water level.
I. a patient who is hypoxemic but normocarbic II. Decrease the oxygen flow rate.
II. a patient who is hypoxemic and hypercapneic III. Replace the apparatus with a small-volume nebu-
III. a patient who is heavily sedated lizer.
IV. a patient who is alert and cooperative IV. Suggest a Mucomyst treatment.
A. I, III only A. II only
B. II, III only B. I, II only
C. I, IV only C. I, IV only
D. II, IV only D. III, IV only

38 Chapter 2: Pretest
92. A 32-year-old craniotomy patient has just returned from 96. Which of the following notations would be appropriate
the recovery room and is still anesthetized. She is re- to make in the chart following an IPPB treatment?
ceiving mechanical ventilation on the following settings:
I. date and time therapy was administered
• mode: SIMV II. dose of medications and diluents placed in the
• ventilatory rate: 8 breaths/min. nebulizer
• tidal volume: 800 ml III. amount of negative pressure needed to trigger the
• FIO2: 0.60 machine
• PEEP: 5 cm H2O IV. volume achieved during the treatment

Her ABG and acid-base data are as follows: A. I, II only

B. I, II, III only
PO2 90 torr; PCO2 32 torr; pH 7.49; HCO 3̄ 23 mEq/liter C. I, II, IV only
If the physician wishes to achieve a PaCO2 of 25 torr D. III, IV only
for the patient, the CRT should recommend
97. Which of the following changes in a patient’s PaO2
I. decreasing the ventilatory rate. would best be detected by a pulse oximeter?
II. changing to the assist–control mode. A. 450–550 mm Hg
III. increasing the tidal volume. B. 250–325 mm Hg
IV. adding mechanical dead space. C. 125–175 mm Hg
V. increasing the ventilatory rate. D. 75–100 mm Hg
A. I, III only
B. II, IV only 98. What is the best position to maintain optimum oxy-
C. II only genation for a patient who has both right-middle and
D. III, V only right-lower lobe pneumonia?
A. Place the patient in a high Fowler’s position.
93. A patient with COPD has coarse rhonchi and a mini- B. Position the patient so the right lung is dependent.
mally productive cough. What therapy is indicated to C. Position the patient so the left lung is dependent.
mobilize his secretions? D. Place the patient in a reverse Trendelenburg position.
A. IPPB 99. Which air-entrainment adaptor (in Figure 2-6), when
B. incentive spirometry attached to the oxygen-delivery device pictured as fol-
C. CPT and percussion lows, would provide the highest FIO2?
D. aerosolized bronchodilators
Air
94. A patient is receiving 10 cm H2O CPAP via a mask. entrainment
port
The CRT notes a 5 cm H2O pressure drop during each
spontaneous breath. To decrease the amount of inspi-
ratory pressure drop, the CRT should
A. instruct the patient to breathe more slowly. Air-entrapment adaptor
B. increase the CPAP setting to compensate for the Jet orifice
pressure drop. A. B. C. D.
C. increase the gas flow going to the patient.
D. incorporate an additional one-way valve into the
system.

Figure 2-6
95. A hospitalized COPD patient has been allowed to eat
lunch in the cafeteria. If she takes a full E cylinder op- 100. Paramedic personnel are performing CPR on a motor
erating at 3 L/min. and leaves at 11 A.M., by what time vehicle accident victim brought into the emergency de-
must she return to avoid running out of oxygen? (Hos- partment. In assessing adequacy of chest compres-
pital policy states that she must return with a reserve of sions, which artery is most appropriate for the CRT to
at least 500 psig in the tank.) palpate?
A. 2:25 P.M. A. carotid artery
B. 2:05 P.M. B. radial artery
C. 1:35 P.M. C. ulnar artery
D. 1:25 P.M. D. brachial artery

Chapter 2: Pretest 39
101. A 58-year-old male COPD patient has the following 105. A seven-year-old patient recovering from chest trauma
respiratory care orders: has been prescribed incentive spirometry using a mod-
ified adult device. The parents say the child will not
Atrovent (ipratropium bromide) MDI:
perform the maneuver at home because she thinks it is
two puffs QID
boring. What can be recommended to encourage the
albuterol MDI: two puffs QID
child to comply with the treatment ordered?
postural drainage with chest percussion QID
I. Talk to the child and explain the need for therapy.
The physician requests that the CRT “space out the ther-
II. Change to a pediatric device with balloons and
apy to maximize the benefits.” Which of the following
clowns.
sequence of therapies would be most appropriate?
III. Tell the parents to make her do it.
I. albuterol at 7 A.M., 11 A.M., 3 P.M., and 7 P.M. IV. Ask the physician to discontinue the therapy.
II. Atrovent at 9 A.M., 1 P.M., 5 P.M., and 9 P.M.
A. I, III, IV only
III. postural drainage to immediately follow each al-
B. I, II only
buterol treatment
C. II, IV only
IV. postural drainage to immediately precede each
D. III, IV only
Atrovent treatment
A. I, III only 106. Which of the following characteristics of sputum
B. II, IV only should the CRT document in the patient’s medical
C. I, II, III only record?
D. II, III only
I. color of the sputum
II. amount of material expectorated by the patient
102. Which of the following assessments should be made
III. consistency of the sputum
immediately following attaching a Passy–Muir valve
IV. odor of the sputum
to a patient’s tracheostomy tube?
A. I, II only
I. Assess the patient’s ability to cough.
B. II, III only
II. Assess the patient’s ability to speak.
C. I, III only
III. Assess the patient’s ability to ventilate.
D. I, II, III, IV
IV. Assess the patient’s breath sounds.
A. I, II, III, IV 107. A patient who has been experiencing increasing pre-
B. I, III only mature ventricular contractions has been placed in the
C. II, III, IV only coronary care unit (CCU) for observation. The cardiol-
D. I, II, III only ogist asks the CRT to recommend an oxygen-delivery
device for this patient. Which of the following oxygen
103. A patient is receiving NPPV via a nasal mask for the appliances would be appropriate for this patient?
treatment of respiratory failure associated with cardio-
A. a partial rebreathing mask at 8 L/min.
genic pulmonary edema. The CRT notices that the
B. a nasal cannula operating at 2 L/min.
nasal mask does not fit the patient well. Which of the
C. a simple oxygen mask at 8 L/min.
following measures should be taken?
D. an air-entrainment mask delivering 40% oxygen
A. Intubate the patient and administer oxygen with a
T-piece. 108. Upon entering the emergency department, the CRT no-
B. Intubate the patient and apply continuous positive tices a patient receiving oxygen via an E cylinder con-
airway pressure. nected to a Bourdon gauge flow meter and lying
C. Intubate and initiate conventional mechanical alongside the patient. What should the CRT do at this
ventilation. time?
D. Use a full face mask.
A. Obtain an oxygen analyzer and analyze the pa-
tient’s FIO2.
104. Regarding before-and-after bronchodilator studies,
B. Obtain an E cylinder cart and place the cylinder
what percent improvement in the FEV1 is generally
upright.
considered significant for determining reversible air-
C. Replace the Bourdon gauge with a compensated
flow obstruction?
Thorpe flow meter.
A.  5% D. Do nothing, because this situation is acceptable.
B.  10%
C.  15% 109. IPPB with albuterol has been ordered for an asthmatic pa-
D.  25% tient postoperatively. Upon preliminary assessment, the pa-

40 Chapter 2: Pretest
 tient is noted to have a vital capacity of 17 cc/kg. What rec- A. I, II only
ommendation should the CRT make regarding therapy? B. III only
C. II, IV only
A. Substitute incentive spirometry for IPPB.
D. I, II, III only
B. Administer albuterol by hand-held nebulizer.
C. Administer analgesics prior to IPPB.
113. A CRT notes that a mechanically ventilated patient in-
D. Follow IPPB with CPT.
tubated with a 7.0 mm (I.D.) oral ET tube experiences
episodes of desaturation, bradycardia, and hypotension
110. When considering the assist–control mode for mechan-
with each suctioning event. What should the CRT rec-
ically ventilating a patient, the CRT should be cognizant
ommend?
of which of the following potential conditions and/or
changes as the patient is managed on the ventilator? A. using a size 14 French suction catheter
B. switching to a size 8.0 mm I.D. ET tube
I. changes in acid-base status caused by fluctuations
C. incorporating a closed-suction catheter system
in the patient’s ventilatory rate
D. changing the ventilatory settings before each suc-
II. decreased venous return as the patient’s ventila-
tioning event
tory rate increases
III. failure to ventilate if the patient ceases sponta-
114. A physician is performing a tracheostomy on an orally
neous breathing
intubated patient and asks the CRT to assist by remov-
IV. increased demand-valve sensitivity causing in-
ing the patient’s endotracheal tube. When should the
creased WOB
CRT remove the endotracheal tube in conjunction with
A. I, II only the tracheostomy procedure?
B. II, III only
A. immediately before the tracheostomy procedure
C. I, II, IV only
begins
D. III, IV only
B. at the time the trachea is surgically entered
C. as soon as the tracheostomy tube is inserted
111. When scheduling CPT for an infant who is being gav-
D. just before the tracheostomy tube is inserted
age fed every three hours, what is the best time to per-
form the treatment in relation to feeding times?
115. During bag-mask ventilation of an obese, comatose
A. one hour before patient, the airway remains partially obstructed despite
B. three hours before neck extension with mandibular traction. What device
C. three hours after should be used to alleviate this problem?
D. one hour after
A. tracheal button
B. transtracheal catheter
112. Which of the following errors is likely when analysis
C. oropharyngeal airway
by co-oximetry is performed on arterial blood from a
D. esophageal obturator
premature infant?
I. falsely low SaO2 116. The CRT is preparing to perform endotracheal suc-
II. falsely high COHb% tioning on a mechanically ventilated patient and ob-
III. falsely low MetHb% serves the ECG tracing (Figure 2-7) below.
IV. falsely low reduced hemoglobin concentration

Figure 2-7: Lead II ECG tracing

Chapter 2: Pretest 41
 Figure 2-8: ECG pattern of an unconscious patient who suddenly becomes pulseless during endotracheal suctioning

During the suctioning procedure, she notices the ECG

pattern in Figure 2-8 displayed on the cardiac monitor.
Which of the following actions should she perform at
this time?
A. Continue suctioning and monitor the patient.
B. Remove the suction catheter immediately.
C. Adjust the vacuum pressure to read –115 mm Hg.
D. Instill 3–5 cc of normal saline into the tracheo-
bronchial tree.

117. A 60-kg status asthmaticus patient is being mechani- A Heated

cally ventilated via a positive pressure ventilator. The Humidifier
ventilator settings are as follows: Figure 2-9: Identify the equipment labeled A.
• mode: SIMV
• V̇E: 16.2 L/min. 119. A patient with a history of asthma is receiving volume-
• f: 18 breaths/min. cycled mechanical ventilation. The PIP has been 25
• TI%: 33% cm H2O but now has increased to 45 cm H2O. Which
• FIO2: 0.40 of the following medications would be appropriate to
• V̇I: 50 L/min. nebulize in-line to the patient?
Upon applying the end-expiratory pause feature on the I. Alupent
ventilator, the CRT notices that an auto-PEEP of 12 cm II. albuterol
H2O registers on the pressure manometer. What should III. Ventolin
the CRT do at this time? IV. Bronkosol
A. Increase the ventilatory rate. A. I, II only
B. Decrease the peak inspiratory flow rate. B. II, IV only
C. Institute PEEP. C. I only
D. Decrease the inspired oxygen concentration. D. I, II, III, IV

118. What is the function of the piece of equipment labeled 120. A CRT is ventilating an intubated patient with a resus-
A in Figure 2-9? citation bag during CPR. The CRT notices no chest ex-
cursion on the left side and an increase in the pressure
A. It helps maintain a constant water level in the hu-
needed to ventilate the patient. Which of the following
midifier reservoir.
actions would be the most appropriate response to this
B. It functions as a backup humidifier when water in
situation?
the heated humidifier becomes depleted.
C. It serves as a water trap for condensation occur- A. Use a demand valve.
ring in the breathing circuit. B. Reintubate the patient with a larger tube.
D. It acts as an oxygen reservoir to maintain a con- C. Insert a nasogastric tube.
stant FIO2 delivered to the patient. D. Withdraw the ET tube somewhat.

42 Chapter 2: Pretest
121. Conditions that clearly demonstrate clinical indica- C. III, IV only
tions for CPT include all of the following EXCEPT: D. II, IV only
A. lung abscess
B. bronchiectasis 125. Which of the following equipment would be useful to
C. cystic fibrosis obtain when preparing to perform orotracheal intuba-
D. empyema tion on an adult patient?
I. stylette
122. The CRT is removing the suction catheter of a closed- II. Miller laryngoscope blade
suction catheter system from the ET tube of a me- III. Magill forceps
chanically ventilated patient. What should she do IV. Yankauer suction tube
before reinserting the suction catheter for another suc-
tioning attempt? A. II, III only
B. I, II, IV only
A. Ventilate the patient with room air via a manual C. I, IV only
resuscitator. D. I, III, IV only
B. Manually ventilate the patient for a few breaths
with the ventilator-established FIO2.
126. Which of the following questions would be most ef-
C. Ventilate the patient for a few breaths using 100%
fective in eliciting information about a patient’s emo-
oxygen through the ventilator.
tional state?
D. Ventilate the patient with 100% oxygen using a
manual resuscitator. A. Are you depressed?
B. Do hospitals scare you?
123. The CRT, while performing ICU ventilator rounds, no- C. What medications are you taking for nerves? Have
tices that a Bourdon gauge is attached to an ET tube you ever had emotional problems in the past?
cuff-pressure measuring device. What should he do at D. How are you feeling about being in the hospital?
this time?
A. Replace the Bourdon gauge with a back-pressure, 127. The CRT is asked to percuss and drain a patient’s lin-
compensated Thorpe tube. gula. How should the patient be positioned?
B. Replace the Bourdon gauge with an aneroid A. Place the patient on the right side, one-quarter
barometer. turn from supine, in a slight head-down position.
C. Do nothing because the Bourdon gauge will ade- B. Place the patient on the left side in a slight head-
quately measure the cuff pressure. down position.
D. Inject 1–2 cc of air into the cuff to determine C. Position the patient on the right side, one-quarter
whether the Bourdon gauge works. turn from prone, in a slight reverse Trendelenburg
position.
124. An MA-1 ventilator has been adapted for use with a con- D. Place the patient on the left side, three-quarters
tinuous-flow IMV system. The ventilator settings include: turn from supine, in a slight Trendelenburg posi-
• PEEP: 10 cm H2O tion.
• tidal volume: 1,000 ml
• mechanical ventilatory rate: 6 breaths/min. 128. A CRT is called to evaluate a 62-year-old COPD pa-
tient who has been admitted to the medical floor for
As the patient begins to inspire, the pressure manometer treatment of pneumonia. Physical examination reveals
needle indicates –5 cm H2O, and the orange indicator a thin male with a barrel chest. The patient appears to
light at the top or the ventilator illuminates. Which of be asleep. He is difficult to arouse for assessment. Aus-
the following conditions does this situation represent? cultation reveals inspiratory crackles in the right lower
I. The IMV flow rate is inadequate. lobe. The patient is currently receiving oxygen at 6
II. The ventilator’s sensitivity control has not been liters per minute via a simple mask. The pulse oxime-
turned off. ter indicates an SpO2 of 97%. With regard to the pre-
III. The safety pop-in valve in the IMV system is not sent therapy, what is the most likely cause of the
opening. patient’s lethargy?
IV. Too much PEEP is being applied, and the reser-
A. oxygen-induced absorption atelectasis
voir bag cannot maintain the pressure.
B. retinopathy of prematurity
A. I, II, III only C. oxygen-induced hypoventilation
B. II, III only D. pulmonary oxygen toxicity

Chapter 2: Pretest 43
129. A physician is planning to orally intubate a patient and His ventilatory rate is 28 breaths/min., and he is using
asks the CRT to prepare the equipment necessary for accessory muscles of breathing with mild retractions.
the procedure. Which of the following equipment Auscultation reveals bilateral wheezes and crackles.
preparations are appropriate? Which of the following therapies are appropriate at
this time?
I. Lubricate the stylette.
II. Attach the laryngoscope blade to the handle. I. aerosol treatment with a beta-adrenergic agent
III. Set the suction pressure to an appropriate setting. II. postural drainage with percussion and vibration
IV. Ensure that the bulb on the laryngoscope blade is III. oxygen by nasal cannula at 1 L/min.
secure. IV. pediatric mist tent
A. I, IV only A. I only
B. III, IV only B. I, III only
C. II, III, IV only C. I, II, III only
D. I, II, III only D. I, II, III, IV

130. After connecting one tube on a Luken’s trap to a suc- 133. When a patient is nasally or orally intubated, generally
tion catheter and the other tube to the connecting tub- how much time should elapse before a tracheotomy is
ing leading to the suction manometer, the CRT notes considered?
that she can no longer generate a vacuum when plac-
A. If the patient is comatose, a tracheotomy should
ing her thumb over the thumb port. Which of the fol-
be done 24 hours after the patient is intubated.
lowing actions should she take at this time?
B. A tracheotomy should be done immediately if tra-
A. Ensure that all connections are secure. cheobronchial secretions are thick.
B. Empty the Luken’s trap. C. If the patient appears to be in further need of the
C. Fill the Luken’s trap with normal saline. artificial airway, a tracheotomy should be done 72
D. Eliminate the Luken’s trap from the suction system. hours after intubation.
D. Because each clinical condition and situation is
131. The CRT is performing endotracheal suctioning on an different, the decision to perform a tracheotomy is
unconscious patient who suddenly becomes pulseless an individualized medical determination.
and displays the ECG tracing on the monitor as shown
in Figure 2-10: 134. Calculate the FIO2 provided by the oxygen-delivery
system pictured in Figure 2-11.
What action is appropriate at this time?
A. Perform a precordial thump. A. 0.40
B. Shake and attempt to arouse the patient. B. 0.48
C. Administer 100% oxygen via a manual resuscita- C. 0.50
tion bag. D. 0.56
D. Begin applying chest compressions at a rate of 80
to 100 per minute. 135. The CRT is having a patient perform a before-and-
after bronchodilator FVC maneuver. Two puffs of an
132. A four-year-old boy with a known history of cystic fi- MDI dispensing ipratropium bromide have been ad-
brosis has been admitted for respiratory distress and a ministered. How long should the CRT wait before the
presumed diagnosis of bacterial pneumonia. His ABG postbronchodilator effort is conducted?
data on room air indicate:
A. 15 minutes
PO2 42 mm Hg; PCO2 55 mm Hg; pH 7.34; HCO 3̄ 29 B. 20 minutes
mEq/liter C. 30 minutes
D. more than 30 minutes

Figure 2-10

44 Chapter 2: Pretest
 A. B. C. 0.43
FIO2 FIO2 D. 0.45
Flow rate: 0.40 0.60 Flow rate:
15 L/min. 10 L/min.
138. Accessory muscle use during quiet breathing may be
apparent in patients with all of the following condi-
tions EXCEPT:
A. pleurisy
Y-piece B. neuromuscular disease
C. spinal cord injury
D. severe COPD

Delivered FIO2? 139. An adult respiratory distress syndrome (ARDS) pa-

tient has been changed from the control mode via a
Figure 2-11: Two flow meters operating a Briggs adaptor
volume ventilator to the pressure-control mode with a
resulting increase in the mean airway pressure. Which
136. A patient who sustained a C-2 fracture in a motorcycle
of the following statements are true regarding an in-
accident is being prepared for transport to the regional
creased mean airway pressure?
spinal cord rehabilitation unit after spending the initial
48-hours postinjury in a local hospital. Although a I. Increased mean airway pressure can result in a re-
heat-moisture exchanger was being used during the duced risk of cardiovascular side effects.
initial two days of mechanical ventilation, the patient II. Increased mean airway pressure can reduce the
developed thick, difficult-to-suction secretions. Which risk of barotrauma.
of the following therapeutic modalities should the III. The mean airway pressure will increase with a
CRT recommend? longer expiratory time.
A. Initiate CPT. IV. Increased mean airway pressure can result in bet-
B. Administer an intravenous (I.V.) fluid bolus. ter arterial oxygenation.
C. Instill 3–5 ml of normal saline solution before A. IV only
suctioning. B. I, II only
D. Lubricate the suction catheter with water-soluble C. III, IV only
gel before suctioning. D. I, III only

137. The CRT is preparing to place a nasal cannula operat-

140. An oxygen blender is being used to deliver 40% O2
ing at 3 L/min. on a patient who has the following
through a jet nebulizer for humidification. How should
spontaneous breathing measurements:
the CRT set the jet nebulizer in this situation?
• tidal volume: 450 ml
A. The jet nebulizer must be set at the same FIO2 as
• ventilatory rate: 12 breaths/min.
the blender.
• I:E ratio: 1:2
B. 100% O2 must be set on the jet nebulizer.
C. Setting the jet nebulizer at an FIO2 of 0.40 or less
Estimate the FIO2 delivered by this device under these
would be acceptable.
conditions.
D. Because the blender is delivering precisely 40%
A. 0.36 O2, the jet nebulizer can be adjusted to any FIO2
B. 0.39 setting.

Chapter 2: Pretest 45
 Chapter 2 Pretest: Matrix Categories
1. IA1g(1) 48. IIA1e(1) 95. IIID8
2. IIB1h(1) 49. IB5a 96. IIIA2a
3. IIB2e(1) 50. IIIE1c 97. IA1f(5)
4. IIIC1d 51. IIB2d 98. IIIC2c
5. IIIC2c 52. IIIC2b 99. IIB1a(2)
6. IIIC1d 53. IA1g(1) 100. IIIF1
7. IIB2f(2) 54. IIID7 101. IIIE1f
8. IIB1q 55. IIA1a(1) 102. IIIE1g(1)
9. IB7b 56. IIIF2 103. IIB2e(2)
10. IIIEli(1) 57. IIB2e(1) 104. IC2a
11. IC2a 58. IIIE1f 105. IIIE1c
12. IIB2a(2) 59. IC2b 106. IIIA1b(3)
13. IB7b 60. IIIC2c 107. ID1d
14. IIIC1a 61. IIIC1h 108. IIB2h(3)
15. IIIE3 62. IIIE1h(2) 109. IIIB2c
16. IIIA1b(4) 63. IIIE1g(2) 110. IIIC1c
17. IIB2m 64. IIB1f(3) 111. IIIA1d
18. IIIA2b(2) 65. IIIB2b 112. IC2c
19. IIIB2c 66. IIIC1f 113. IIIE1h(2)
20. IIIE1g(4) 67. IB1b 114. IIIG1c
21. IIA1a(2) 68. IIID6 115. IIIB1a
22. IIIEli(1) 69. ID1c 116. IIIE1h(1)
23. IIIA1 70. IB1b 117. IIIC2a
24. IC2c 71. IIIE1i(1) 118. IIB1b
25. IIID7 72. IIB1j 119. IIIC1g
26. IB7b 73. IIIA1b(3) 120. IIIE1g(1)
27. IIB1f(4) 74. IIIF1 121. IIIB2a
28. IIIE3 75. IIIE1g(1) 122. IIIC2c
29. IIB1h(3) 76. IIIE1h(1) 123. IIB2m
30. IIIF1 77. IC2a 124. IIIC1f
31. IIB2e(2) 78. IIA1m(1) 125. IIB1f(4)
32. IIIE1b(3) 79. IIID5 126. IB5a
33. IIIG1d 80. IIIC1a 127. IIIB2a
34. IC1d 81. IB5a 128. IIIA2b(1)
35. IC2a 82. IIB1h(1) 129. IIIG1e
36. IIIE1d(3) 83. IIB2f(1) 130. IIB2g
37. IIIA2b(1) 84. IIIE1i(1) 131. IIIF2
38. IIIG2c 85. IA1f(3) 132. ID1c
39. IIB1q 86. IIIG2c 133. IIIE1g(1)
40. IIB1a(2) 87. IIA1f(3) 134. IIA1a(2)
41. IIID10 88. IIB1e(1) 135. IC1b
42. IIA1f(1) 89. IIIE1h(1) 136. IIIE1h(4)
43. IIIE2d 90. IIIC1c 137. IIA2a
44. IIB1h(4) 91. IIIE1e(1) 138. IB1b
45. IIB2h(3) 92. IIIE1i(1) 139. IIID7
46. IIID3 93. IIIB2a 140. IIB1c
47. IIIE1b(1) 94. IIB2a(3)

46 Chapter 2: Pretest
Table 2-3: Pretest—Entry-Level Examination Matrix Scoring Form

Entry-Level Examination Pretest Pretest Items Pretest Content

Content Area Item Number Answered Correctly Area Score

I. Clinical Data
A. Review data in the patient record and 1, 53, 85, 97 __ × 100 = ___ %
4
recommend diagnostic procedures.
B. Collect and evaluate clinical information. 9, 13, 26, 49, 67, __ × 100 = ___ %
9 __ × 100 = ___ %
70, 81, 126, 138
25
C. Perform procedures and interpret 11, 24, 34, 35, 59, __ × 100 = ___ %
9
results. 77, 104, 112, 135
D. Determine the appropriateness and 69, 107, 132 __ × 100 = ___ %
3
participate in the development of the
respiratory care plan and recommend
modifications.
II. Equipment
A. Select, obtain, and assure equipment 21, 42, 48, 55, 78, __ × 100 = ___ %
9
cleanliness. 87, 103, 134, 137
B. Assemble and check for proper equipment 2, 3, 7, 8, 12, 17, __ × 100 = ___ %
28 __ × 100 = ___ %
function, identify and take action to correct 27, 29, 31, 39, 40,
36
equipment malfunctions, and perform 44, 45, 51, 57, 64,
quality control. 72, 82, 83, 88, 94,
99, 108, 118, 123,
125, 130, 140
III. Therapeutic Procedures
A. Explain planned therapy and goals to 16, 18, 23, 37, 73,
the patient, maintain records and 96, 106, 111, 128 __ × 100 = ___ %
9
communication, and protect the patient
from noscomial infection.
B. Conduct therapeutic procedures to 19, 65, 93, 109, __ × 100 = ___ %
7
maintain a patent airway and remove 115, 121, 127
bronchopulmonary secretions.
C. Conduct therapeutic procedures to 4, 5, 6, 14, 52, 60, __ × 100 = ___ %
16
achieve adequate ventilation and 61, 66, 80, 90, 98,
oxygenation. 110, 117, 119, 122,
124
D. Evaluate and monitor patient’s response 25, 41, 46, 54, 68, __ × 100 = ___ % __ × 100 = ___ %
8 79
to respiratory care. 79, 95, 139
E. Modify and recommend modifications 10, 15, 20, 22, 28, __ × 100 = ___ %
28
in therapeutics and recommend 32, 36, 43, 47, 50,
pharmacologic agents. 58, 62, 63, 71, 75,
76, 84, 89, 91, 92,
101, 102, 105, 113,
116, 120, 133, 136
F. Treat cardiopulmonary collapse according 30, 56, 74, 100, 131 __ × 100 = ___ %
5
to BLS, ACLS, PALS, and NRP.
G. Assist the physician and initiate and conduct 33, 38, 86, 114, 129 __ × 100 = ___ %
5
pulmonary rehabilitation and home care.

Chapter 2: Pretest 47
 Pretest Answers and Analyses
NOTE: The references listed after each analysis are numbered and keyed to the reference list located at the end of
this section. The first number indicates the text. The second number indicates the page where information
about the questions can be found. For example, (1:114, 187) means that on pages 114 and 187 of reference
1, information about the question will be found. Frequently, you will need to read beyond the page num-
ber indicated to obtain complete information. Therefore, reference to the question will be found either on
the page indicated or on subsequent pages.

IA1g(1) This design results in the needle indicating a flow rate

1. B. The MAP represents the average arterial pressure greater than the patient is actually receiving. In fact,
exerted through a cardiac cycle (i.e., systole and dias- because the Bourdon gauge is uncompensated for back
tole). The formula for calculating the MAP is illus- pressure, the disparity between the flow rate indicated
trated as follows. and the actual flow rate becomes greater when resis-
tance to flow increases.
2 (diastolic pressure) + systolic pressure
MAP = Because of its design, however, the Bourdon gauge is
3 suitable for patient transport situations when the flow
2(80 torr) + 140 torr meter has to be placed horizontally. This position does
= not alter the flow rate indicator, whereas with a Thorpe
3 flow meter, the flow rate indicator (ball) will roll and
300 torr prevent a flow rate from being read.
=
3 (1:731–732), (5:48–50), (13:57–58), (15:868),
(16:359–360).
= 100 torr
The MAP is affected by the vascular volume and the IIB2I(1)
vascular capacity. How much blood is in circulation 3. D. To terminate inspiration, the PR series requires a
will be influenced by clinical conditions such as hem- terminal flow of 3 L/min., which is achieved when the
orrhage and fluid administration. Vascular capacitance pressure gradient between the machine and the pa-
depends on the state of the vascular smooth muscle tient’s airway approaches zero. Any leak at all might
(i.e., vasocontriction or vasodilation). make this cycling off impossible. Additionally, the PR
series has small internal leaks. To compensate for
Because the normal systolic and diastolic pressure
these small leaks and others in the circuit, the PR-2 has
ranges are 90–140 torr and 60–90 torr, respectively, the
a terminal flow control. This control adds flow distal to
MAP normally ranges between 70 and 105 torr.
the Bennett valve to compensate for these leaks and to
(1:183, 943), (10:136), (16:237). enable the flow through the Bennett valve to reach the
level necessary for it to stop gas flow to the patient.
IIB1h(1) (5:217, 220–228), (13:349–351).
2. A. The device illustrated with this question is a Bour-
don gauge. A Bourdon gauge is a pressure gauge. The IIIC1d
face of the Bourdon gauge, however, can be calibrated
4. D. STEP 1: Determine the length of the ventilatory
to measure the flow rate of a gas.
cycle (total cycle time [TCT]) by using the following
The design of a Bourdon gauge makes it more suitable relationship:
to measure pressure. The gauge contains a hook-
# of sec./min.
shaped, dead-ended, hollow copper tube that expands = TCT
when the hollow copper tube is pressurized. As the ventilatory rate
copper tube becomes pressurized, its compliant quality 60 sec./min.
causes it to straighten somewhat. The end of the = 1.33 sec./breath
hooked tube is attached to connecting rods, which in 45 breaths/min.
turn are in contact with a geared apparatus. The center STEP 2: Determine the number of time segments
of the gear mechanism connects to a needle that ulti- comprising the desired I:E ratio. The desired
mately deflects as the gear rotates. I:E ratio of 1:2 has three time segments (i.e.,
1  2 = 3).

48 Chapter 2: Pretest
 STEP 3: Compute the inspiratory time by dividing the For the NBRC exams, candidates should use the range of
length of the ventilatory cycle by the number 10–15 ml/kg of IBW as the guideline for establishing the
of time segments comprising the I:E ratio. initial tidal volume for mechanically ventilated patients.
1.33 sec. (1:896–897), (10:207–208), (15:717), (16:620).
= 0.443 sec. (TI)
3
STEP 4: Calculate the inspiratory flow rate (V̇I ) by
A. Room air
dividing the tidal volume (VT) by the inspira-
tory time (TI).
VT
= V̇I
TI
40 ml
= 90 ml/sec. . .
0.443 sec. Normal Low VA/QC
(1:860, inside back cover), (10:206).

IIIC2c
5. A. Low V̇A/Q̇C units, or areas where perfusion exceeds
ventilation, and diffusion impairments are amenable to
.
oxygen therapy. Capillary shunting—lung units re- Q Normal mixture .
exc s ad Q
ceiving perfusion but not ventilation—cannot be cor- ha ou
ng en
rected by oxygen therapy. A collapsed or completely

V
e
obstructed alveolus will not exchange gases regardless
of the FIO2 breathed.
Figure 2-12 illustrates how low V̇A/Q̇C lung units (perfu-
.
sion in excess of ventilation or shunt effect) can impair Q
blood oxygenation and how increasing the FIO2 can cor-
rect the problem. In the top figure, when room air is
breathed, the low V̇A/Q̇C alveolus mimics a capillary
shunt, and a venous admixture ultimately combines
with blood that has been normally exchanged. The re-
sult can be hypoxemia. Oxygenation can be improved, 100% 02
B.
as in the bottom figure, when the FIO2 is increased (e.g.,
1.0). Oxygen molecules displace nitrogen molecules,
and more oxygen molecules move past the partial ob-
struction, thereby improving oxygenation to the distal
alveolus. Consequently arterial oxygenation improves.
. .
Depending on the nature of the diffusion impairment, Normal with Low VA/QC
more O2 with O2
an increased FIO2 ordinarily corrects the hypoxemia.
(1:221–222, 820), (10:100–101), (16:131).

IIIC1d
6. C. The general guideline used for establishing an ini-
tial tidal volume for a patient who is about to receive .
.
volume mechanical ventilation is to deliver some- Q Normal d oxygenation
exc ove Q
where between 10 to 15 cc/kg of IBW.
ha
ng pr
Im
e

In the clinical setting, this range changes depending on

the patient’s underlying condition. Asthmatic patients
who do not respond to the usual pharmacologic and
therapeutic regimens ordinarily prescribed for acute .
asthmatic episodes (status asthmaticus) are ventilated Q
at a volume range of 7 to 10 cc/kg. COPD patients re-
Figure 2-12: (A) Normal lung and low V̇/Q̇ lungs exposed
quiring mechanical ventilation receive tidal volumes in to room air, resulting in hypoxemia; (B) Normal and low V̇/Q̇
the 8–10 cc/kg range. lungs exposed to 100% O2, correcting hypoxemia.

Chapter 2: Pretest 49
IIB2f(2) Because the right lung appears hyperlucent, it is hy-
7. A. An 85-kg adult patient who requires mechanical ven- perinflated. Therefore, physical exam findings that are
tilation is generally intubated with a size 8.0 to 9.5 mm consistent with hyperaerated lung tissue can be ex-
internal diameter (I.D.) ET tube. A size 7.0 mm I.D. tube pected. These physical exam findings include:
is generally used in adult females and older children. • absent or diminished breath sounds
The patient described in the question has been intubated • hyperresonant percussion note
with an endotracheal tube too small for his airway. • absent or diminished tactile fremitus
Therefore, too large a volume had to be injected into the If the right lung were radiopaque, it would be fluid
cuff to seal the airway. The greater the volume injected filled or consolidated. The physical exam findings
into the cuff, the greater the intracuff pressure. A high characteristic of such lung tissue would be anticipated,
intracuff pressure has adverse effects on the tracheal tis- that is,
sue in contact with the endotracheal tube cuff.
• absent or diminished breath sounds; bronchial
Intracuff pressure should range between 20 and 25 mm breath sounds if alveoli are collapsed, fluid filled, or
Hg (27–34 cm H2O). Although a high-volume, low- consolidated with airways patent
pressure cuffed tube is used, cuff overinflation can • dull percussion note
cause tracheal necrosis and/or tracheal dilatation. • absent or diminished tactile fremitus if consolidation
Excessive tracheobronchial secretions or broncho- is not connected with patent airways; otherwise, in-
spasm will not affect the pressure to the cuff of an en- creased tactile fremitus
dotracheal tube. Both conditions will increase the (1:308–313, 404), (9:58–65, 150), (16:167–173, 205).
airway resistance through the tracheobronchial tree. A
malfunction with the one-way valve would likely IIIE1i(1)
cause air to leak out of the cuff or would prevent air
10. B. Auto-PEEP is the development of positive alveolar
from being injected into the cuff (or both).
pressure at end-exhalation and is different from thera-
(1:594, 609), (5:257–259), (13:126, 130–134), peutically applied PEEP. Auto-PEEP develops in me-
(16:573, 576). chanically ventilated patients whose ventilator settings
are inappropriate or in some ventilated patients who
IIB1q have dynamic airflow obstuction (e.g., COPD and
asthma).
8. B. The danger of aspiration of small coins or other
small objects is present when an MDI is carried in a Auto-PEEP does not register on the ventilator’s pres-
purse or pocket with the mouthpiece uncovered. This sure manometer; therefore, it is also referred to an
possibility should always be considered. The water test unidentified PEEP, or intrinsic PEEP. Auto-PEEP can
indicated that the MDI is approximately half full. An be determined by instituting an expiratory hold just as
empty MDI would float. Although shaking an MDI be- the ensuing inspiration is about to begin, and delaying
fore actuation is appropriate, the patient indicated that that inspiration. Initiating an end-expiratory hold at
she did not feel like she was getting any medication. that particular point enables the equalization of pres-
Because the MDI was used earlier in the day, medica- sure throughout the lung-ventilator system and results
tion should have been delivered even without vigorous in the auto-PEEP registering on the pressure gauge.
shaking. If not used within 24 hours, an MDI should
Figure 2-13A illustrates a normal alveolar pressure on
be charged by turning it upside-down and discharging
exhalation with no expiratory flow present when the
it. The actuator orifice should be disinfected once a
next inspiration begins. Figure 2-13B demonstrates a
week or according to the manufacturer’s instructions.
positive alveolar pressure developed at end-exhalation
This practice would not affect actuation, however.
(auto-PEEP) in the presence of airway obstruction. No-
(5:134), (13:144–145). tice that the ventilator’s pressure manometer registers
zero, despite the presence of 10 cm H2O of auto-PEEP
IB7b in the alveoli. Figure 2-13C shows how the auto-PEEP
can be quantified (i.e., via an end-expiratory hold). In
9. B. Lungs that are filled with a normal volume of air
this case, the pressure equilibrates throughout the sys-
appear radiolucent (blackened film) on a chest X-ray.
tem, and the auto-PEEP is measured.
Hyperaerated lungs (as in pulmonary emphysema or
asthma) appear hyperlucent (darker than normal) be- Auto-PEEP can be decreased by making any of the
cause of the increased volume of air. Lungs containing following ventilator adjustments: (1) decreasing the
fluid (edema or consolidation) present as radiopaque ventilatory rate, (2) shortening the inspiratory time, (3)
(whitened film). lengthening the expiratory time, (4) decreasing the

50 Chapter 2: Pretest
 cm H2O
Pressure
10 gauge
0 Exhalation
A.
port (open)

End–exhalation
Ventilator (no air flow)

0 0
(cm H2O) (cm H2O)

cm H2O
Pressure
10 gauge
0 Exhalation
B. port (open)
Airway
obstuction

End–exhalation
Ventilator (no air flow)

10 10
(cm H2O) (cm H2O)

cm H2O Pressure
10 gauge
0 Exhalation
C. port (closed)
Airway
obstuction

End–exhalation
Ventilator (no air flow)

10 10
(cm H2O) (cm H2O)

Figure 2-13: (A) Intra-alveolar pressure equals atmospheric pressure (no auto-PEEP) at
end-exhalation, with the exhalation port exposed to the atmosphere. (B) Auto-PEEP (intra-
alveolar pressure) of 10 cm H2O exists at end-exhalation with the exhalation port exposed
to the atmosphere, while the pressure gauge indicates 0 cm H2O. Note the presence of an
airway obstruction. (C) Auto-PEEP of 10 cm H2O registers on the pressure gauge at end-
exhalation with the exhalation port closed. Note the presence of an airway obstruction.

Chapter 2: Pretest 51
 tidal volume, (5) using less compliant (stiffer) ventila- The patient’s peak inspiratory flow rate is obviously
tor tubing, and (6) adding applied PEEP. exceeding 32 L/min., because aerosol mist is disap-
pearing from the end of the Briggs adaptor with each
Increasing the tidal volume would increase auto-PEEP,
breath. Increasing the flow rate to 15 L/min. of 40%
because a larger tidal volume would take longer to ex-
oxygen will provide the patient with a total flow rate of
hale. If the ventilatory rate were decreased, the tidal
60 L/min. Reservoir tubing must always be attached to
volume may necessarily increase to preserve an ade-
the distal end of the T-piece.
quate minute ventilation. The effect of the increased
tidal volume, however, would be an increase in auto- (1:756–757), (5:180–182), (16:392–394).
PEEP.
Bronchial hygiene should also be considered for the IB7b
removal of secretions to alter the airway-resistance 13. C. The degree of the clinical manifestations of pleural ef-
factor. Remember that the ventilation time constant is fusion will depend on the volume of fluid that enters the
the product of the lung compliance multiplied by the intrapleural space. Essentially, the severity of a pleural ef-
airway resistance. fusion is volume dependent. For example, a small volume
of fluid in the intrapleural space may be asymptomatic
(1:828, 917), (15:901–906), (16:318, 621, 625, 684). and radiographically present with a blunted costophrenic
angle, a small meniscus sign, and/or a partially obscured
IC2a hemidiaphragm. A large pleural effusion, however, can
11. B. A lower than normal FVC could be indicative of ei- manifest itself as a complete “white out” (opacification)
ther a restrictive or obstructive impairment. Comparing on the affected side and thus can completely obscure the
the patient’s FEV1 to his FVC with the FEV1/FVC ratio affected hemidiaphragm.
is helpful to differentiate an obstructive impairment
Characteristically, a large enough pleural effusion can
from a restrictive impairment. An obstructive impair-
radiographically present itself as a complete opacifica-
ment is typified by an FEV1/FVC ratio that is less than
tion on the side of the thorax where the fluid has accu-
0.75. Chronic bronchitis and pulmonary emphysema are
mulated. Additionally, if the volume of fluid on the
typical obstructive pulmonary diseases. A restrictive im-
affected side is sufficiently large, the mediastinum and
pairment will be evidenced by a decreased FVC with an
trachea will deviate to the unaffected side.
FEV1/FVC greater than or equal to 0.75. A restrictive
disease will often cause the FEV1/FVC ratio to be Atelectasis, however, if severe enough, will cause the
higher than normal (greater than 0.85). Sarcoidosis and mediastinum and trachea to shift toward the affected
ascites are two examples of a restrictive impairment. side. A pneumothorax will not cause complete opacifi-
cation because air is radiolucent. The trachea and me-
(1:391, 394), (6:30–40), (11:120–124), (16:228–229).
diastinum will shift toward the unaffected lung if the
volume of trapped air is large enough.
IB2a(2)
12. A. Disappearance of the aerosol with each inspiration (1:406, 481), (15:53, 117, 438), (16:177, 196, 214–215).
indicates that the patient is entraining room air through
the distal end of the Briggs adaptor, because the flow IIIC1a
rate of the gas from the nebulizer is less than the pa- 14. B. Because it is usually considered that the deposition
tient’s peak inspiratory flow rate. Thus, this device is and retention of aerosol particles are inversely related
no longer functioning as a high-flow oxygen-delivery to the patient’s ventilatory rate and directly related to
system, and the actual FIO2 that the patient is receiving her tidal volume, the patient should be instructed to in-
is unknown. The Briggs adaptor should be set up with hale slowly and deeply and hold her breath at end-
reservoir tubing attached to the end. The appropriate inspiration. This inspiratory pattern, along with a slow
action in this case is to increase the total flow rate to exhalation through pursed lips, will generally enhance
the patient. particle penetration and deposition.
The total flow rate that the patient is receiving here is (15:802), (16:448).
32 L/min. This flow rate is calculated based on know-
ing that a 40% oxygen concentration has an air:oxygen IIIE3
ratio of 3:1 (i.e., three parts air and one part oxygen). 15. A. Asthma patients who have daily symptoms of the
Because 8 L/min. of the delivered flow rate represents disease require prophylactic, as well as symptomatic,
the flow rate of oxygen, the delivered flow rate of air is therapy. The prophylactic therapy is directed toward
three times the oxygen flow rate, or 24 L/min. There- controlling the inflammatory component of the dis-
fore, the total delivered flow rate is 8 L/min. of oxy- ease, while symptomatic therapy is intended to prevent
gen, plus 24 L/min. of air, or 32 L/min. asthma manifestations.

52 Chapter 2: Pretest
 Inhaled corticosteroids are often effective in abating tential benefits of PEEP were ignored, and the FIO2
the inflammatory process. Inhaled beta-two agonists was increased to 0.70.
(albuterol and metaproterenol) are generally beneficial
The patient still appears to be unresponsive to the in-
in maintaining bronchodilation. Similarly, oral theo-
creased FIO2, indicating refractory hypoxemia. Re-
phylline administered to establish a serum level of
fractory hypoxemia was likely recognized when the
10–20 g/ml is frequently prescribed to control bron-
FIO2 was 0.60 and resulted in the PEEP trial.
chospasm. Many physicians are de-emphasizing theo-
phylline because of serious side effects. What the CRT should recommend is that PEEP be in-
stituted. To proceed as empirically as possible, how-
Asthmatics who display mild, infrequent, or seasonal
ever, another PEEP trial at the present FIO2 (0.70)
symptoms (and those who have uncontrolled symp-
should be conducted. In the situation presented here,
toms requiring frequent clinic or emergency room vis-
the data from the PEEP trial were presumably not er-
its and hospitalization) are managed differently.
roneous. Either the data were misinterpreted, or they
(1:454–456), (15:682–683), (16:1005–1010, were not understandable to the person who was re-
1012–1014). sponsible for the clinical decision.
Inverse-ratio ventilation may ultimately be needed;
IIIA1b(4) however, at this time, there is no data to support its ap-
16. A. Adrenergic bronchodilators may stimulate both plication.
beta-one and beta-two receptors. One of the most fre-
quent adverse reactions associated with their adminis- (1:899, 911), (4:766), (9:188), (18:371–378, 385).
tration is tachycardia. If the patient’s heart rate
increases more than 20 beats/min. during the course of IIIB2c
a treatment, the CRT should terminate the procedure 19. C. The patient needs the saline lavage to help mobilize
and notify the physician. Changing the dose of med- the secretions. The evidence of infiltrates could have
ication, frequency of treatment, or the specific bron- resulted from infection or possibly from a mucous
chodilator might be appropriate. plug. A bronchodilator such as albuterol should be ad-
ministered in light of the history of asthma. The bron-
(AARC Clinical Practice Guidelines for Assessing Re-
chodilator will help decrease bronchoconstriction and
sponse to Bronchodilator Therapy at Point of Care),
aid in mucous clearance, along with the saline lavage.
(1:702–704), (15:181), (16:444, 494–496).
(1:452–456, 1041), (15:215–217, 681–682),
IIB2m (16:984–987, 1001–1017).
17. C. The setup pictured in the question is correct. The
one-way valve permits the patient to exhale but not in- IIIE1g(4)
hale when the thumb port is covered. This arrangement 20. C. An intracuff pressure of 33 torr is excessive. There-
forces the patient to exhale to low lung volumes, max- fore, air needs to be removed from the cuff to get the
imizing her diaphragm’s capability to contract, thereby intracuff pressure within the range of 20 to 25 torr.
optimizing the test. Reversing the valve would only
Intracuff pressures exceeding 18 mm Hg restrict the
measure a maximum expiratory pressure. Not covering
flow of tracheal venous blood in that region. Intracuff
the thumb port would result in no pressure being mea-
pressures exceeding 30 mm Hg cause tracheal arterial
sured on the manometer. The maximum inspiratory
blood flow to be obstructed.
pressure measurement is uncomfortable for the patient,
but it does provide a valuable indicator of the patient’s Ideally, intracuff pressure should seal the airway by
inspiratory muscle strength and ability to cough. Ex- means of the least amount of pressure possible. The
plaining the procedure, coaching, and careful monitor- maximum acceptable range of intracuff pressure is 20
ing of the patient during the test are important. to 25 mm Hg or 27 to 34 cm H2O.
(1:825, 971, 1096), (6:52–53), (16:234–235). (2:428), (4:504–505), (5:472–473).

IIIA2b(2) IIA1a(2)
18. B. The appropriate decision was not made following 21. C. A tracheostomy collar or a T-piece (Briggs adaptor)
the PEEP study. The PEEP study indicated that the pa- can provide the needed oxygen, as well as humidifica-
tient had a favorable response to levels of PEEP at tion and heat. For these devices, only the air-entrain-
least up to 8 cm H2O, and at a PEEP level of 10 cm ment port on the nebulizer can be varied to adjust the
H2O, all the physiologic markers used to evaluate the oxygen delivery setting. The tracheostomy collar rests
effectiveness of PEEP deteriorated. Seemingly, the po- loosely over the opening of the tracheostomy tube at

Chapter 2: Pretest 53
 the stoma site. Therefore, the actual delivered FIO2 is mEq/liter. These changes are both classified as aci-
virtually unpredictable, because depending on the pa- doses; therefore, the pH should be significantly lower
tient’s inspiratory flow rate and respiratory frequency, than 7.35. Because it is not, there must be some kind of
various amounts of room air can be entrained. error in the results. This result should not be used for
making clinical decisions. Because the bicarbonate and
If a tracheostomy patient requires a high and/or precise
base excess (B.E.) values are calculated by the blood
FIO2, a T-piece (Briggs adaptor) is the appliance of
gas analyzer, the analyzer may be malfunctioning.
choice. A T-piece fits snugly on the 15 mm adaptor of
the tracheostomy tube. The only room air that can en- (1:266–279, 350–351), (4:133–144), (15:482–483),
ter the system at the point of the patient’s airway is the (16:265–267).
distal end of the T-piece. As long as the patient’s in-
spiratory flow rate does not exceed that of the output IIID7
of the nebulizer, the set FIO2 should be achieved. If the
25. C. Patients may “fight the ventilator,” or breathe asyn-
patient’s inspiratory flow rate exceeds the output of the
chronously, because of technical errors in setting ma-
nebulizer, the patient’s FIO2 will be less than that set
chine parameters. If the patient does not “feel” like he
at the room air entrainment port of the nebulizer.
is getting enough air, he may try to buck the machine.
(1:755–756), (7:422–424), (16:391–394). Inadequate flow rates from the ventilator or from an
IMV gas source cause lengthy inspiratory times that
IIIE1i(1) are unable to satisfy the need for volume in an ex-
22. D. A decrease in lung compliance indicates that the pected time period. The flow rates must be sufficiently
lungs are more difficult to inflate. A greater pressure is high and the inspiratory time sufficiently short, with
required to deliver the same volume. On a controlled adequate volume delivery to satisfy a person’s inspira-
volume-cycled ventilator, reduced compliance may be tory needs. Clinically related conditions, such as pa-
discernible by a higher PIP indicated on the pressure tient anxiety, irritability, and acid-base disturbances,
manometer. The manometer reflects system pressure, could also be reasons for “fighting” the ventilator.
which includes the compliance and resistance charac- (1:913–915), (15:1004), (16:622).
teristics of the lungs.
(1:390–391, 937–938), (15:334, 893–894), IB7b
(16:245–246, 319, 1098). 26. B. Crackling sensations and sounds noted during per-
cussion of the chest wall are indicative of subcuta-
IIIA1 neous emphysema. Air leaking from the lung into the
23. B. Most patients do not correctly use their MDIs. Con- subcutaneous tissues produces small pellets of air that
sequently, this skill deteriorates further over time, and are trapped under the skin. This condition is some-
their asthma is less controlled. times noted after the insertion of a tracheostomy tube
or is sometimes associated with a pneumothorax. Air
Effective training steps for teaching MDI techniques under the skin is usually not a life-threatening condi-
include: tion, but the presence of the air could be an indication
1. Telling the patient the steps of the procedure of a potentially hazardous situation existing else-
2. Providing the patient with written instructions where, specifically in the thorax or lungs. The source
3. Demonstrating the procedure for the patient of the air leak must be determined. The condition is
4. Having the patient perform a demonstration referred to as subcutaneous emphysema, and the sen-
5. Informing the patient of what was performed cor- sation produced upon palpation of the skin is known
rectly and what was done improperly as crepitus.
6. Having the patient demonstrate the procedure again (1:309–310), (9:60), (16:170, 207).
On subsequent office or home visits, have the patient
demonstrate the procedure. Provide feedback to the IIB1f(4)
patient. 27. D. The curved (e.g., Macintosh) laryngoscope blade
(Practical Guide for the Diagnosis and Management of should be placed between the base of the tongue and
Asthma). above the epiglottis. This region is termed the vallec-
ula. The straight blade (e.g., Miller) is placed under the
IC2c anterior portion of the epiglottis, to expose the glottis.
Figure 2-14 illustrates the visualization of the glottis.
24. D. The ABG report does not make clinical sense. The
PaCO2 is above 45 mm Hg, and the HCO3̄ is below 22 (1:597), (16:580, 588, 591, 594).

54 Chapter 2: Pretest
 IIB2e(2)
31. D. NPPV can be used to treat patients who have either
acute or chronic ventilatory failure in acute care set-
tings or in alternate care sites. Whenever NPPV is ap-
plied, a few criteria must be heeded, including the
following: (1) absence of an artificial airway, (2) he-
Tongue modynamic stability, (3) intact upper-airway reflexes
Vallecula (decreased risk of aspiration), and (4) a cooperative
patient.
Epiglottis
In this question, the patient is presented as having dif-
Vocal Cord ficultly with swallowing, which indicates an increased
risk for aspiration. Therefore, the NPPV must be dis-
Glottis continued, and the patient must be intubated and me-
chanically ventilated.
Arytenoid
cartilage (1:895, 982, 1122, 1128), (10:192, 399), (16:616,
1137).
Figure 2-14

IIIE1b(3)
IIIE3
32. C. Patients who receive IPPB therapy commonly hy-
28. D. Though ultrasonic nebulizers are used for sputum
perventilate during the treatment. Therefore, the pa-
induction, the CRT must be aware that patients with
tient must be instructed to breathe slowly and deeply.
dry, copious secretions may react negatively to the
The patient’s tidal volume is also increased as a result
large volume of dense aerosol. Dried mucus may swell
of the positive pressure. An increased minute ventila-
and occlude the airways. Airways may also spasm. Ul-
tion results in hypocarbia. The signs of hypocarbia in-
trasonic nebulizers are not recommended for use with
clude dizziness, numbness, paresthesia (tingling of the
asthmatics for this reason.
extremities), and tetany (muscle spasms). These symp-
(1:699), (15:803–804), (16:461). toms develop as a direct result of an acute respiratory
alkalosis produced by the hyperventilation. The patient
IIB1h(3) should be given a period of rest to enable these symp-
29. D. The National Fire Protection Agency (NFPA) has toms to subside before completing the treatment.
established recommendations and regulations con- (1:781), (16:532–533)
cerning bulk oxygen systems. The following specifi-
cations according to the NFPA pertain to the vaporizer. IIIG1d
The vaporizer can be arranged in columns as long as
33. A. Cardioversion resembles defibrillation in that they
the connecting pipes are securely anchored and con-
both involve the application of electricity to the my-
structed of suitably flexible material to enable the ex-
ocardium. This electric shock delivered to the heart
pansion and contraction resulting from temperature
muscle causes the fibers of the myocardium to depo-
fluctuations. Heat can be supplied to the vaporizer, as
larize. Defibrillation refers to the delivery of an elec-
long as it is applied indirectly. Steam, air, or water can
tric shock to the myocardium at any time during the
be used, because these substances do not react with
cardiac cycle. Defibrillation is indicated for ventricular
oxygen. The vaporizers would need to be electrically
fibrillation and for pulseless ventricular tachycardia.
grounded if liquid heaters were used with the vapor-
izer. Commonly, the vaporizer—where the liquid oxy- Cardioversion refers to the use of electric shock to the
gen converts to a gas—is heated by the environment. cardiac musculature, specifically at the point of the
Therefore, under those conditions, no grounding is R wave on the electrocardiogram. During the R wave,
necessary. both ventricles experience depolarization. The timing
of the application of the electric shock and this
(1:723), (15:874–875), (16:346, 348).
physiologic event is critical, because electrical activity
during the T wave (refractory period) can induce ven-
IIIF1 tricular fibrillation or ventricular tachycardia. The fol-
30. D. To perform external cardiac massage, the rescuer lowing cardiac dysrhythmias indicate the use of
places the base of the palm of the hand on the lower cardioversion:
third of the victim’s sternum.
• supraventricular tachycardia (SVT)
(1:636–637), (15:1113–1120), (16:821–822). • atrial flutter

Chapter 2: Pretest 55
 • atrial fibrillation C.
• ventricular tachycardia (VT)
Assisted breath Mandatory (controlled) breath
Another difference between cardioversion and defib- +

PRESSURE
(cm H2O)
rillation is that fewer joules (watts/second) are used
during cardioversion than during defibrillation. 0
I E I E Subambient (negative)
(AARC Clinical Practice Guidelines for Defibrillation pressure generated by patient
During Resuscitation), (1:653–657), (16:814–817). – triggering assisted breath

IC1d TIME (sec)

34. D. IMV is depicted by Tracing D. Positive pressure Figure 2-15c: Assist-control mechanical ventilation
breaths are available via the control mode, while the
patient is capable of breathing spontaneously in-be- D.
tween these mandatory ventilations. The mandatory Mandatory Spontaneous
(controlled) ventilations are depicted by the large breath ventilations
+

PRESSURE
(higher amplitude) deflections above the baseline. The Stacked

(cm H2O)
breath
spontaneous breaths are represented by those below
the baseline and the small (lower-amplitude) upward 0
deflections above the baseline. The other modes of I E I E I E I E
ventilation shown in the question were: –

A = controlled mechanical ventilation TIME (sec)

B = assisted ventilation Figure 2-15d: Intermittent mechanical ventilation
C = assist-control ventilation
(1:861), (5:387), (13:632), (15:957–958), (15:665–668).
The waveforms (pressure-time tracings) that follow
(Figures 2-15a–d) represent all four of the modes of IC2a
ventilation presented here. The letter I indicates the
35. C. To calculate the percent of the predicted normal
length of the inspiratory phase, and the letter E signi-
value, divide the patient’s largest FEV1 by the pre-
fies the duration of the expiratory phase. Deflections
dicted normal FEV1 and convert it to a percentage ac-
below the baseline depict subambient or negative pres-
cording to the following formula:
sure generated by the patient during spontaneous in-
spiratory efforts. FEV1 (actual)
 100 = percent predicted
A. FEV1 (predicted)
Mandatory breath 3.60 liters
+  100 = 86%
PRESSURE

4.20 liters
(cm H2O)

0 (American Thoracic Society, “Standardization of

I E Spirometry 1987 update,” 1987, Am Rev Respir Dis,
–
136, pp. 1285–1298; Reprinted in Respiratory Care,
1987, 32, pp. 1039–1060), (1:391).

TIME (sec) IIIE1d(3)

Figure 2-15a: Controlled mechanical ventilation 36. D. Increasing and decreasing flow rates to a jet nebu-
lizer will increase and decrease the output, respec-
B. tively. Decreasing the FIO2 will increase output as air
entrainment increases. Shortening the tubing has a
Assisted breath
variable and minimal effect of increasing the aerosol
+
PRESSURE

output. Heating the aerosol will increase the output.

(cm H2O)

0 (1:752–758), (5:54), (13:76–79).

I E Subambient (negative)
– pressure generated by patient
triggering assisted breath IIIA2b(1)
37. D. The patient has a right, based on the principle of
TIME (sec) autonomy, to decline any treatment even if it will pro-
Figure 2-15b: Assisted mechanical ventilation long his life. Health-care practitioners coercing an indi-

56 Chapter 2: Pretest
 vidual to reverse a refusal of treatment is unethical. Ten (10) parts of the ratio represent the entrained air flow
Understandably, the patient must be provided with ade- (10  3 L/min. = 30 L/min.), and the oxygen flow repre-
quate information to comprehend his available options. sents one part of the ratio (1  3 L/min. = 3 L/min.).
Adding the flow rates comprising the ratio provides the
(1:66), (15:1214).
total flow delivered to the patient (i.e., 30 L/min. air + 3
IIIG2c L/min. O2 = 33 L/min). Therefore,
38. A. When set at an oxygen flow rate of 2 liters/min., air flow rate 30 L/min. 10
= =
portable liquid-oxygen units generally offer a patient O2 flow rate 3 L/min. 1
five to eight hours of oxygen. The duration of oxygen
delivery from these portable units can be extended by Table 2-4 illustrates approximate air:oxygen ratios for
using oxygen-conserving devices, such as the pendant certain oxygen percentages.
reservoir cannula. By using the pendant reservoir can- Furthermore, the following formula can be used to ob-
nula instead of a standard cannula, the patient usually tain a more precise calculation of the delivered flow
requires a lower flow rate of oxygen. For example, if a rate:
patient needs 2 liters/min. of oxygen from a standard
nasal cannula to maintain a satisfactory oxygen satu- Table 2-4: Approximate Air:O2 Ratios for Given O2%
ration, he may require only a 0.5 liter/min. flow rate O2% Air:O2 Ratio*
with a pendant reservoir cannula. Such a device sig-
nificantly extends the time of oxygen supply. 24 25:1
28 10:1
(1:748–749, 1115), (16:383–385, 898–899). 30 8:1
35 5:1
IIB1q 40 3:1
39. A. The consensus at this time, as to when to actuate an 50 1.7:1
MDI used in conjunction with a mechanical ventilator, 60 1:1
depends on whether a ventilator MDI adaptor or 70 0.6:1
spacer is used. If no spacer is used, the MDI should be 100 0:1
actuated immediately after the beginning of a mechan- *The entrained air flow is assumed to contain 20.9% oxygen.
ical breath. When a mechanical ventilator MDI adap-
tor is used, the MDI should be actuated 1–2 seconds (CS  V̇s ) + (CENT  V̇ENT) = (CDEL  V̇DEL )
before a mechanical breath or near end-exhalation.
(100%  3 L/min.) + (21%  30 L/min.) = 28% (V̇DEL )
(1:706–709), (15:815–817), (16:456).
300 L/min. + 630 L/min. = 28 (V̇DEL)
IIB1a(2)
930 L/min.
40. A. The 28% adaptor at 3 L/min. would provide a total = V̇DEL
28
flow of 33 L/min. The calculations are outlined below.
33.2 L/min. = V̇DEL
STEP 1: Determine the patient’s inspiratory flow rate
(V̇I) using the following formula: (1:752, 860), (5:54), (16:361–363).
VT
V̇I =
TI IIID10
41. D. Incentive spirometry is the therapy of choice for
500 ml
= this patient. Incentive spirometry encourages the pa-
1 sec. tient to perform hyperinflation techniques necessary to
= 500 ml/sec. prevent atelectasis. Incentive spirometry should be
given both pre- and postoperatively to aid in the pre-
STEP 2: Convert 500 ml/sec. to L/min. vention of postoperative atelectasis. Incentive spirom-
a. (500 ml/sec.)(60 sec./min.) = 30,000 ml/min. etry is less costly and less invasive for the patient than
IPPB therapy. Incentive spirometry can easily be
b. 30,000 ml/min. taught to most alert patients. Chest physiotherapy
= 30 L/min.
1,000 ml/L should not be used as a preventive measure but as a
treatment for the mobilization of retained secretions.
Because the air:oxygen ratio for an FIO2 of 0.28 is 10:1,
a source liter flow of 3 L/min. will deliver 33 L/min. of The patient should be continually monitored to evalu-
total gas flow (entrained air + source gas) to the patient. ate the effectiveness of therapy. This evaluation needs

Chapter 2: Pretest 57
 to include: (1) chest auscultation to note changes in mon cause of clinical deterioration associated with
breath sounds, (2) achievement of incentive spirometry nasal CPAP devices.
goals (increased lung volumes), and (3) assessment of
(1:784–786), (16:340, 565).
chest radiographs to note the appearance of lung
changes.
IIID3
(AARC Clinical Practice Guidelines for Incentive 46. C. Depending on what artery was used to obtain the
Spirometry), (1:774–777), (5:197), (16:529–530). blood sample, digital pressure should normally be ap-
plied to the puncture site for a minimum of five minutes.
IIA1f(1) If a femoral puncture was performed, pressure to the site
42. A. An oropharyngeal airway that is too long for the pa- must be applied for more than five minutes. If the pa-
tient may impinge on the epiglottis, forcing it down so tient is anticoagulated or has a bleeding disorder, direct
that it obstructs the larynx. During bag-mask ventila- pressure must be applied for a longer time. Two minutes
tion, air may enter the stomach, and thus gastric dis- after the pressure is released, the site should be in-
tention may occur. Both of these occurrences would spected for signs of bleeding. If any bleeding, oozing, or
prevent effective alveolar ventilation. If a comatose seepage of blood is present, pressure should be contin-
person with an oropharyngeal airway in place becomes ued until such bleeding ceases. Pressure dressings or
conscious, stimulation of the oropharynx may cause Band-Aids are not substitutes for compression.
gagging, vomiting, or laryngospasm. (1:341), (4:6), (16:270–271).
(1:647–648), (5:255–256), (13:158), (16:565–567).
IIIE1b(1)
IIIE2d 47. A. Exerting –2 cm H2O to initiate inspiration is normal
43. B. COPD patients frequently experience air trapping in conjunction with IPPB therapy. If a patient is exert-
while being mechanically ventilated. One way to min- ing more than –3 cm H2O to cycle on the machine, the
imize this effect is to use a high peak inspiratory flow sensitivity control requires adjustment to enable the
rate and a tidal volume with a lower ventilatory rate to patient to cycle on the machine more easily.
permit adequate time for exhalation. In this case, the In this situation, no adjustment is necessary—because
I:E ratio is set for a patient who has normal lungs. De- –2 cm H2O represents a normal inspiratory effort.
creasing the ratio to 1:4 will permit longer expiratory
times and promote lung emptying. There are many (1:781).
signs of air trapping in ventilator patients, regardless
of whether they have COPD. Increasing PIP and IIA1e(1)
plateau pressures, decreasing compliance, presence of 48. A. The delivered tidal volume would increase as the flow
auto-PEEP, decreased breath sounds, and increasing rate was decreased because less volume/time (V̇) would
resonance to percussion are just a few. Other condi- be delivered to the system. As a consequence, inspiratory
tions that increase the risk of air trapping are small ET time would increase. The longer the time provided for in-
tubes, increased age, and increased minute ventilation. spiration, the better distribution of inhaled gas.
(1:880, 900), (15:1001–1002). (1:899–901, 915), (10:210), (16:620).

IIB1h(4) IB5a
44. D. Pulse oximeters are a noninvasive way to monitor 49. D. The first characteristic to determine in evaluating a
oxygen saturation. Oxygen saturation is measured by patient’s mental status is orientation to time, place, or
comparing the wavelengths of a red and an infrared person. The patient should have some idea as to date,
light. Oximeters are affected by patient and probe mo- day of the week, and time of day. He should be aware
tion, a misaligned or dirty probe, decreased perfusion, of where he is in general terms, such as in the emer-
temperature, dysfunctional hemoglobin, intravenous gency department in Buffalo, New York. He should
dyes, and bright ambient lights. also recognize his own identity as well as the identity
of people who are significant to him.
(1:361), (5:321–322), (6:144–145, 183).
(1:301–302), (9:39).
IIB2a(3)
45. A. Because the nasal prongs extend only 0.5–1 cm into IIIE1c
each anterior nare, nasal prongs need to be securely 50. B. Incentive spirometers are designed for inspiratory
fastened. Dislodgement of the prongs is the most com- maneuvers; blowing into them provides no benefit.

58 Chapter 2: Pretest
 Candidates for incentive breathing therapy must be worsen the alkalemia. Control-mode ventilation would
alert and conscious and have the ability and desire to not accomplish anything that could not be achieved in
follow instructions. They should have eyesight that is the assist-control mode. Regarding the bronchodilator,
adequate to see the device and watch it function. This nothing in this situation warrants its use.
elderly woman does not meet the criteria for appropri-
Because the FIO2 is 1.0 and the arterial PO2 reflects
ate administration of incentive spirometry. In fact, the
moderate to severe hypoxemia, PEEP should be initi-
AARC clinical practice guidelines for incentive
ated. Instituting 5 cm H2O of PEEP represents a rea-
spirometry have determined the following as con-
sonable starting point. The clinician must measure the
traindications: (1) patients who cannot be instructed or
patient’s compliance, arterial PO2 and cardiac output
supervised to ensure appropriate use of the device, and
(if possible) as PEEP is instituted or increased further.
(2) patients whose cooperation is absent, or patients
who are unable to understand or demonstrate proper (1:879–881, 902), (10:240, 267–268, 272),
use of the device. (15:899–901).
Emphasis on breathing out (as with the use of “blow
bottle”) will do nothing to accomplish alveolar infla- IA1g(1)
tion, save the preparatory inspiration the patient may 53. B. The pulse pressure is the difference between the
take before the maneuver. systolic and diastolic blood pressures. For example, a
patient with a blood pressure of 100/80 mm Hg would
(AARC Clinical Practice Guidelines for Incentive have a pulse pressure of 20 mm Hg (e.g., 100 mm Hg
Spirometry), (1:774–777), (16:529–532). –80 mm Hg = 20 mm Hg). Pulse pressures provide the
force to cause perfusion through the body. Pulse pres-
IIB2d sures of less than 25–30 mm Hg result in difficult-to-
51. D. While another resuscitation bag may ultimately palpate peripheral pulses.
solve the problem, there is an urgent need to restore
(1:942), (10:118), (15:432), (16:162).
adequate ventilation to the patient. Of course, periodic
disconnection is impractical. Allowing more time for
exhalation will not help, because the nonrebreathing IIID7
valve is jammed in the inspiratory position. Although 54. B. When CPAP is applied by mask, a tight seal must be
the latest American Society for Testing and Materials maintained to keep pressure levels above atmosphere
(ASTM) standards for self-inflating manual resuscita- pressure. Any significant leaks in the system will result
tors require proper function at up to 30 L/min. of in the loss of positive airway pressure. Patients receiv-
oxygen input, not all clinically available manual re- ing CPAP must be closely and continuously monitored
suscitators perform at this flow rate. Newer resuscita- for unwanted effects. CPAP devices must be equipped
tors conform to these standards, whereas older models with a means to monitor the level of pressure delivered
may not. Therefore, the CRT should reduce the flow to the airway and must have alarms to indicate the loss
meter output to 15 L/min. A negligible effect will oc- of pressure caused by a system disconnect or mechan-
cur on the delivered FIO2, but the nonrebreathing valve ical failure.
will be enabled to function properly. Inspiratory pressure changes are affected by the sys-
(5:270–277), (13:193–200). tem’s capability of providing sufficient gas volume to
satisfy continuous patient inspiratory demands. An
IIIC2b ideal CPAP system should be capable of maintaining a
near constant ( 2 cm H2O) baseline pressure. To min-
52. B. This patient is experiencing an oxygenation prob-
imize pressure fluctuations, flows through the system
lem. The arterial PO2 is expected to be much higher
generally will need to be either in the 60–90 L/min.
than 45 torr, because the patient is receiving 100%
range or at least four times the patient’s minute venti-
oxygen. No need exists to increase the patient’s tidal
lation (4  V̇E ). The pressure alarm and a pressure
volume, because she is already receiving 13.8 ml/kg.
manometer should be placed as close to the patient’s
This value is obtained as follows:
airway as possible. An in-line oxygen analyzer should
VT (ml) 900 ml also be placed in the system before the gas enters the
= = 13.8 ml/kg
body weight (kg) 65 kg humidification system.

Ordinarily, patients should receive a tidal volume (1:783–784, 865), (10:281–282), (16:537–539).
within the range of 10 to 15 cc/kg of IBW. Similarly, the
ventilatory rate does not need to be increased because IIA1a(1)
the patient’s arterial PCO2 is 33 torr, resulting in a pH of 55. D. The oxygen-delivery apparatus illustrated repre-
7.52 (alkalemia). Increasing the rate further would sents a pendant cannula, which is used to conserve

Chapter 2: Pretest 59
 oxygen particularly for home usage. The device has this patient is not the amount of oxygen she receives,
been reported to reduce oxygen usage from 50% to but the humidity. Patients having surgery on their nose
70%. often cannot breathe through their nose for a period of
time. Therefore, humidification must be provided be-
(1:748–749), (5:58–60), (13:68–69), (16:383–384, 899).
cause the patient becomes predominantly a mouth
breather. At the same time, keeping the nasal packs
IIIF2 moist prevents adherence of the packs to the nasal mu-
56. B. The cardiac dysrhythmia appearing on the ECG cosa when the packs are changed.
monitor in this question is ventricular fibrillation. Ac-
cording to the American Heart Association, the only (1:755), (13:77–78), (16:391–393).
effective treatment for ventricular fibrillation is defib-
rillation. Once defibrillation has been applied at 200 IC2b
joules (J), it can be repeated two more times at 59. A. Oxygen delivery to body tissues is primarily de-
200–300 J, then again at 360 J if ventricular fibrillation pendent on C.O. and the amount of hemoglobin avail-
or ventricular tachycardia persists. able to carry oxygen. If the patient has an abnormally
low hemoglobin concentration, and even if the avail-
Depending on the outcome of each defibrillation, dif-
able hemoglobin is 100% saturated with oxygen, the
ferent courses of action are taken. If, for example, ven-
low oxygen-carrying capacity may produce hypox-
tricular fibrillation or ventricular tachycardia persist,
emia. Another condition that can affect the accuracy of
(1) CPR continues, (2) endotracheal intubation takes
a pulse oximeter includes hypothermia, which would
place, and (3) an I.V. access is obtained.
decrease peripheral perfusion. Hyperthermia would
Then, epinephrine (1 mg I.V. push) is given and re- have no effect. Hyperbilirubinemia also affects the ac-
peated every three to five minutes following defibrilla- curacy of a pulse oximeter, but the bilirubin level must
tion. If the ventricular fibrillation or ventricular exceed 10 mg/dl. The oxyhemoglobin dissociation
tachycardia persists, Class IIb dosing regimens begin curve depicts the relationship between the PO2 and the
(i.e., intermediate, escalating, and high epinephrine SpO2, (SO2), but different levels of PaO2 do not affect
doses). the accuracy of pulse oximeters. When the PaO2 is 100
mm Hg, the percent oxyhemoglobin should be ap-
Lidocaine (1.0 to 1.5 mg/kg I.V. push) is not adminis-
proximately 98%, and the performance of a pulse
tered until defibrillation is given again (i.e., after the
oximeter is unaffected.
epinephrine is pushed) and only if ventricular fibrilla-
tion persists. (1:359–363, 928), (5:320–321), (13:255–256),
(16:310–312).
(American Heart Association, Advanced Cardiac Life
Support, 1994, pp. 1–16 to 1–18 and 4–1), (16:853–854).
IIIC2c
IIB2e(1) 60. B. The stated guideline for the maximum time it
should take to insert an ET tube is 30 seconds. If ET
57. B. The I:E ratio light illuminates when expiration is
intubation takes longer than 30 seconds, the procedure
shorter than inspiration. This alarm situation often ac-
must be interrupted, and the patient must be oxy-
companies a high ventilatory rate. The high-pressure
genated for three to five minutes before the intubation
alarm may indicate patient coughing, presence of se-
attempt. In fact, the patient must be preoxygenated be-
cretions, or breath stacking, as well as a variety of
fore the initial ET intubation attempt is made.
other problems. These types of alarm situations are of-
ten self-correcting; once corrected, the audible alarms In the situation presented here, the CRT is confronted
will cease. The visual alarm displays, however, and a with intubating a patient who has congestive heart fail-
large orange “caution” light will remain until the alarm ure, particularly left-ventricular failure. Patients who
reset button is pressed, in which case, the alarm lights have left-ventricular failure sometimes experience or-
will clear and the green “normal” becomes lit. These thopnea (i.e., difficulty breathing in the supine posi-
alarms also indicate that the patient should be assessed tion). The orthopnea results from the increased venous
for equal, bilateral breath sounds and that suctioning return associated with placing the patient in the supine
should be performed if indicated. position. As venous return increases, the C.O. of the
right ventricle increases. The left ventricle is unable to
(5:483–489), (13:494–499).
increase its output, however. Consequently, blood be-
gins to pool in the pulmonary vasculature, and the pa-
IIIE1f tient develops dyspnea as oxygenation becomes a
58. C. A face tent will enable this patient to receive the hu- greater problem. Because of these pathophysiologic
midity, and it will not rest on the bridge of her nose in consequences, the CRT must halt the ET intubation
the same manner as an aerosol mask. The concern with procedure, sit the patient up, and oxygenate the patient

60 Chapter 2: Pretest
 for three to five minutes before attempting to insert the IIIE1h(2)
ET tube again. Orthopnea not only occurs in patients 62. D. Suctioning has the potential for a number of com-
who have congestive heart disease but also in patients plications, including hypoxemia, dysrhythmias, hy-
with COPD and diaphragmatic weakness. potension, and lung collapse. If the suction catheter is
(1:595). too large for the ET tube, it may increase the incidence
of some of these complications. The diameter of the
IIIC1h suction catheter should be not more than one-half to
two-thirds the internal diameter of the ET tube. The
61. D. When a patient is being evaluated as a candidate for
original suction catheter (16 Fr) used was too large. A
weaning from mechanical ventilation, an array of phys-
12 Fr catheter is a more appropriate size.
iologic assessments are available to lend information
concerning the patient’s likelihood for success. Clinical When suctioning neonates, the guideline that the suc-
experience has shown that a variety of measurements tion catheter should be no larger than one-half to two-
should be obtained, because predictability of success in thirds of the internal diameter of the ET tube does not
the weaning process cannot be made based on one cri- apply. The internal diameter of a neonatal ET tube is
terion. At the same time, the use of multiple criteria rather small. Therefore, using a suction catheter one-
does not guarantee success, either. The potential for half to two-thirds that size would require the suction
successful weaning increases when clinical judgment is catheter to be extremely small. Such a small suction
founded on multiple factors, however. catheter would render suctioning difficult. Conse-
quently, the largest possible suction catheter that can
Table 2-5 lists a number of physiologic measurements easily fit down the neonatal ET tube should be used.
and guidelines that have proved to be useful in assess- Because the neonatal ET tube is cuffless, air may enter
ing patient readiness for weaning from mechanical the lungs from around the ET tube, replacing air suc-
ventilation. tioned out through the suction catheter.
(1:971), (15:1020–1023), (16:630). (1:618, 1014–1015), (16:604).
Table 2-5: Criteria for Weaning from Mechanical Ventilation
IIIE1g(2)
Clinical Factor Acceptable Status 63. D. Tugging and pulling on the tracheostomy tube by a
Briggs adaptor is common in an active patient. A tra-
Ventilatory rate < 25 breaths/min.
cheostomy collar would eliminate the direct pull on
Tidal volume Three times body weight (kg) or  the tracheostomy tube. Additional tubing would add
2–3 ml/kg further weight to the system and would potentially in-
Vital capacity Three times predicted VT or > 10 crease pulling on the tracheostomy tube. Restraining
ml/kg (IBW) the patient is not necessary.
Minute ventilation < 10 L/min.
(16:580–582, 599–600).
Ventilatory pattern Regular ventilatory pattern
Maximum inspiratory > –20 cm H2O for at least 20 sec. IIB1f(3)
pressure
64. B. An increase in peak inspiratory pressure may indi-
Dead space/tidal < 0.60
cate problems in the ventilator tubing (such as kinking
volume ratio
or water accumulation), problems with the artificial air-
Shunt fraction < 25%–30%
way (e.g., kinking or mucous plugging), or problems
Alveolar-arterial < 350 torr on 100% O2 with the patient (such as accumulation of secretions or
PO2 difference a pneumothorax). Artificial airways can become ob-
Arterial PO2 to > 238 torr structed for a variety of reasons, including: (1) kinking
FIO2 ratio (P/F) or biting of the tube, (2) herniation of the cuff over the
Arterial to alveolar > 0.47 tube tip, (3) impingement of the tube orifice against the
PO2 ratio (a/A) tracheal wall, and (4) mucous plugging. Of course, it is
Dynamic compliance > 25 ml/cm H2O impossible for a patient with a tracheostomy tube to
Sensorium Alert and cooperative bite the tube, and kinking of the tracheostomy tube is
Vital signs Normal and stable unlikely because of the stiffness of the tube. A leak in
the cuff would lead to a loss of volume and therefore a
Airway secretions Normal viscosity and amount
decrease in peak inspiratory pressure.
Arterial blood gas/ Near patient’s baseline
acid-base data arterial PO2 > 60 torr on FIO2 < 0.40 (1:611), (15:837).
minimal to no PEEP

Chapter 2: Pretest 61
IIIB2b IIID6
65. C. The presence of tracheobronchial secretions causes 68. C. The slow vital capacity (SVC) test is performed by
an increase in airway resistance. An increase in airway instructing the patient to inhale as deeply as possible
resistance in mechanically ventilated patients results in and then slowly blow out all the air in the lungs. The
high PIPs. The PIP may reach the high-pressure limit, patient should be coached by encouraging a maximal
thus activating the high-pressure alarm. effort and volume. A slow exhalation may enable more
air to be exhaled from the lungs, because a slow exha-
The sound of gurgling in the patient’s airways generally
lation helps eliminate air trapping. In some patients, a
signifies the presence of increased tracheobronchial se-
forceful exhalation causes the airways to close prema-
cretions. Therefore, the action that most likely needs to
turely because of the high intrathoracic pressures pro-
be taken is tracheobronchial suctioning. The instillation
duced (dynamic compression). Because the FVC
of normal saline may also be necessary in this situation,
maneuver often causes airways to collapse in patients
but it is not the best response.
who have obstructive lung disease, the SVC should
(AARC Clinical Practice Guidelines: Endotracheal also be measured when a reduction of the FVC is
Suctioning of Mechanically Ventilated Adults and noted.
Children with Artificial Airways), (1:616, 620),
(1:376, 394), (6:27–32), (11:79).
(15:836–837), (16:606–607).

IIIC1f ID1c
66. B. Both IMV and SIMV permit the patient to breathe 69. A. Generally, oxygen is used to prevent or correct ar-
spontaneously between mandatory positive pressure terial hypoxemia, to decrease the work of breathing,
breaths. Potential advantages of IMV and SIMV include and to prevent or minimize the increased cardiopul-
reduction of mean airway pressures, prevention of atro- monary workload associated with compensatory re-
phy of respiratory muscles from inactivity, and avoid- sponses (cardiovascular) to hypoxemia and hypoxia.
ance of respiratory alkalosis induced by the ventilator. Although these terms are often incorrectly and inter-
IMV was originally introduced as a weaning mode in the changeably used, you should note the difference be-
early 1970s and can provide full or partial ventilatory tween hypoxemia and hypoxia. Hypoxemia is a blood
support. Pressure support is another newer mode of ven- condition, defined as a decreased dissolved oxygen
tilation that can be used to adjust the workload of the level in the arterial blood (i.e., a decreased arterial PO2).
muscles of ventilation. Control and assist–control modes An inadequate oxygen supply to the tissues is called hy-
are useful when full ventilatory support is required and poxia. Hypoxia can be localized or generalized. Exam-
when resting the respiratory muscles is desired. ples of local vascular hypoxia include myocardial
infarction (MI, or heart attack) and a cerebrovascular ac-
(1:848, 860), (16:616–617). cident (stroke). Hypoxia may be present in the absence
of hypoxemia. In conditions such as severe anemia,
IB1b shock, stroke, or myocardial infarction, the PaO2 may be
67. D. Patients who have a metabolic acidosis, especially quite high; however, the tissue demands for oxygen are
a diabetic ketoacidosis, tend to breathe deeply and not being met.
rapidly. This ventilatory pattern is described as Kuss-
The patient described here does not need to have an
maul’s breathing. These patients frequently have arte- ABG analysis to document arterial hypoxemia to ben-
rial PCO2s in the teens or single digits. efit from oxygen therapy. The most basic treatment
Patients having a restrictive lung disease (e.g., as- recommendation for acute myocardial infarction in-
bestosis and neuromuscular disease) often breathe volves oxygen therapy. Provision of supplemental
rapidly and shallowly. oxygen by nasal cannula is routinely recommended
for all patients with suspected myocardial infarction,
Cheyne-Stokes breathing is described as crescendo- because it may significantly improve oxygenation of
decrescendo (waxing-waning) breathing followed by a an ischemic myocardium—in other words, a local hy-
long apneic interval. Patients who are in heart failure, poxia.
drug-induced respiratory depression, and uremia com-
monly display this pattern. The compensatory response of the cardiopulmonary
system to hypoxemia or local hypoxia involves both in-
Biot’s breathing is still another irregular breathing pat- creased ventilation and C.O. Some patients breathing
tern. This condition is characterized as irregular room air may achieve acceptable arterial oxygenation
breathing accompanied by lengthy periods of apnea. by increasing their alveolar ventilation and WOB. How-
Biot’s breathing can be caused by an increased in- ever, the higher ventilatory demand may require an in-
tracranial pressure. crease in their C.O. If oxygen therapy can adequately
(1:308), (9:116, 225), (15:675), (16:167). relieve the WOB, the workload on the circulatory

62 Chapter 2: Pretest
 system can be reduced. These aspects are particularly • exhibited a VD/VT of 0.46 (VD based on 1 cc/lb of
important when the heart is already stressed by disease, ideal body weight)
as in MI.
VD 185 cc
= = 0.46
(ACLS: A Comprehensive Review, 3rd ed., K. Grauer and VT 400 cc
D. Cavallaro, Vol. II, pp. 348–349). (13:66), (16:381).
• had a spontaneous minute ventilation of less than
IB1b 15.3 L/min. (i.e., 18 breaths/min.  0.85 L = 15.3
L/min.
70. C. Decreased function or paralysis of the diaphragm
• demonstrated a spontaneous ventilatory rate of less
usually results in a decreased vital capacity and a de-
than 25 breaths/min.
crease in maximal inspiratory force, because the di-
aphragm is the major muscle of inspiration and the Table 2-6: Mechanical Ventilation Weaning Criteria
strongest muscle in a normal individual. Decreased di-
aphragmatic function will also result in paradoxical Physiologic Value/Acceptable
abdominal movement as the abdomen is pulled in by Measurement/Evaluation Finding
the negative pressure of inspiration. Individuals with Sensorium Alert and oriented
little or no diaphragmatic function will also usually ex-
Blood pressure Normal
hibit dyspnea when lying supine, because the di-
aphragm is pushed upward by the abdominal contents Heart rate Normal
which then compresses the lungs. Ventilatory drive Normal
Tidal volume Three times body weight (kg)
Normal diaphragmatic excursion during deep breath-
ing is approximately 5–7 cm. Decreased diaphrag- Vital capacity > 15 ml/kg
matic function or paralysis generally results in a MIP > –20 cm H2O
decreased vital capacity and a decreased maximum in- Ventilatory rate < 25 breaths/min.
spiratory pressure. Decreased diaphragmatic function Minute ventilation < 10 L/min.
will also produce paradoxical abdominal movements. VD/VT < 0.60
This paradoxical movement is characterized by an in-
ABG and acid-base data Within patient’s normal limits
ward abdominal movement during inspiration. The
while breathing FIO2 of < 0.40
negative intrathoracic pressure accounts for the ab-
Tracheobronchial secretions Normal quality and amount
dominal movement in that direction. Upon exhalation,
the abdomen will move outward.
(1:308–309), (9:58, 61), (16:171). The patient’s IMV rate was reduced from 10 breaths/
min. to 6 breaths/min., however. This reduction, which
lowered the mechanical minute ventilation from 8.5
IIIE1i(1)
L/min. (10 bpm  0.85 L) to 5.1 L/min. (6 bpm 
71. D. Criteria for weaning from mechanical ventilation 0.85 L), may have been too drastic at the onset of the
are shown in Table 2-6. weaning procedure. In fact, the recommended reduc-
Before the weaning procedure was instituted, this pa- tion of the IMV or SIMV rate is in decrements of 2
tient met a number of criteria that were used to deter- breaths/min. Therefore, when this patient’s weaning
mine suitability for weaning. For example, the patient: procedures began, his IMV rate should have been low-
ered to 8 breaths/min. This reduction would have low-
• was oriented ered the minute ventilation from 8.5 L/min. to only 6.8
• had a normal blood pressure (130/80 torr) L/min. (8 bpm  0.85 L).
• had reasonable acid-base data (slight respiratory
alkalosis) Based on the accumulated patient information, it is rea-
• displayed an adequate oxygenation status (greater sonable to conclude that this patient’s mechanical
than 90% SaO2 with a PaO2 of 70 torr on an FIO2 of minute ventilation was lowered too quickly. The result
0.40) appears to have caused the patient’s cardiopulmonary
• maintained an adequate spontaneous tidal volume status to deteriorate. This deterioration was manifested
(i.e., 400 cc; greater than three times kg body by: (1) increased blood pressure, (2) increased heart
weight) rate, (3) decreased spontaneous tidal volume, (4) in-
creased spontaneous ventilatory rate (greater than 25
185 lbs breaths/min.), (5) increased arterial PCO2, (6) de-
= 84 kg
2.2 lbs/kg creased pH, and (7) decreased arterial PO2. Therefore,
it appears appropriate to increase this patient’s IMV
84 kg  3 = 252 cc rate to 8 breaths/min., thereby increasing his mandatory

Chapter 2: Pretest 63
 minute ventilation from 5.1 L/min. to 6.8 L/min. Close develop inside the cuff. High intracuff pressures can
monitoring will, of course, be necessary. interfere with arterial and venous blood flow through
the vessels in the tracheal wall in contact with the
(1:848, 878, 977), (15:1032–1033), (16:616, 666).
tube’s cuff.
IIB1j Arterial blood flow through the trachea is around 30
72. B. Because the physician ordered 40% oxygen to be mm Hg, or 42 cm H2O. Venous outflow pressure is
delivered, the mist tent’s top must not be open. An about 18 mm Hg, or 24 cm H2O. Therefore, an in-
open-top tent will provide barely more than room air tracuff pressure range of 20–25 mm Hg (27–33 cm
oxygen levels. The flow meter setting to generally de- H2O) is acceptable. If less pressure can be generated
liver 40% oxygen via the mist tent is about 15 L/min. within the cuff and still afford an effective seal, how-
Therefore, in this situation, the CRT needs to obtain a ever, then larger volumes of air should not be injected
closed-top tent and establish a flow rate of 15 L/min. into the cuff. Table 2-7 outlines the approximate circu-
to operate the device. An oxyhood is inappropriate for latory pressures that exist in the trachea.
this size (five-year-old) patient. The oxyhood would be Table 2-7: Tracheal Circulatory Pressures
rather confining and would likely result in decreased
use. Arterial Venous

(5:83–84), (13:79–81). mm Hg cm H2O mm Hg cm H2O

30 42 18 24
IIIA1b(3)
73. A. Objective criteria are important to use when evalu- In this situation, an intracuff pressure of 42 cm H2O or
ating how well a particular treatment is meeting its 30 mm Hg is too high, because it could impede tra-
goals. Auscultation of the chest is an important cheal capillary blood flow (causing tracheal necrosis).
method of physical examination that may indicate the The appropriate action to take is to release some of the
effectiveness of the therapeutic regimen. In this case, volume from the cuff to reduce the intracuff pressure
the improvement in aeration and possible clearance of to an acceptable level. That range again is 20–25 mm
secretions are signs that the therapy is effective. No in- Hg, or 27–33 cm H2O.
formation exists, such as wheezing, suggesting that a
bronchodilator should be added to the treatment at this (1:609–610), (16:576).
time or that any adverse reactions are occurring. Other
factors used to evaluate bronchial hygiene therapy in- IIIE1h(1)
clude sputum production, WOB, pulmonary function 76. C. Endotracheal suctioning should be performed
studies, blood-gas measurement, and chest radiogra- whenever clinically indicated, with special considera-
phy. tion for the potential complications associated with the
procedure. Endotracheal suctioning is not a benign
(1:310–313), (9:62–67), (16:171–174).
procedure, and health-care professionals should re-
frain from following rote habits that have little ratio-
IIIF1 nale or justification. Routine suctioning of a patient
74. A. The patient described here appears to have re- should be discouraged. The decision to suction a pa-
sponded favorably to the resuscitation efforts, as evi- tient should be based on current physical assessment
denced by an SpO2 of 93%, a blood pressure of 130/80 findings, including coarse rhonchi, tactile fremitus,
torr, and a heart rate of 75 beats/min. The blood-gas and ineffective cough.
data are inconsistent with these findings, however. The
CRT should request that another blood gas sample be (“Clinical Practice Guidelines: Endotracheal Suction-
obtained, because the more recent one probably is con- ing of Mechanically Ventilated Adults and Children
taminated with blood from the femoral vein. with Artificial Airways,” 1993, Respiratory Care,
38(5), pp. 500–504). (1:616), (16:601–602).
(4:29), (9:105).
IC2a
IIIE1g(1) 77. C. A restrictive disease may not impose airflow restric-
75. B. The amount of pressure placed into the cuff of a tra- tions, but it does reduce the size of lung volumes and
cheostomy or ET tube is critical from two standpoints. capacities. In severe restrictive lung disease, the lungs
First, an adequate seal within the airway is essential may be so small and elastic that the entire vital capac-
for proper ventilation, especially during positive pres- ity may be exhaled in one second or less, which would
sure mechanical ventilation. Second, extreme care mean that the FEV1 could potentially equal the FVC.
must be taken to ensure that excess pressure does not
(1:391, 393), (6:78), (11:121), (15:472–473).

64 Chapter 2: Pretest
IIA1m(1) LEVELS OF CONSCIOUSNESS
78. A. A water or mercury column can be used to confirm Confused
the accuracy of an aneroid manometer or an electronic
transducer. A simple mercury blood-pressure manometer
• Minor decreases in consciousness
will suffice. A supersyringe would be appropriate to con-
• Delayed mental responses
firm the accuracy of a volume measuring device, such as
• Diminished perception
a spirometer. A precision Thorpe tube would be used to
• Incoherent
calibrate flow. A hygrometer measures humidity.
(6:306–307), (11:369). Delirious

IIID5 • Confused
79. B. Sympathomimetics (beta-two agonists) as a group • Prone to agitation
sometimes evoke side effects. These side effects in- • Irritable
clude: • Hallucinatory

• fear Lethargic
• anxiety
• tachycardia • Drowsy
• palpitations • Easily aroused
• skeletal muscle tremors • Appropriately responds upon arousal
• restlessness
• dizziness Obtunded
• weakness
• pallor • Difficult to arouse
• hypertension • Appropriately responds upon arousal
• tension (nervousness)
Stuporous
Some beta-two agonists, such as isoproterenol, have a
greater tendency to produce some of these side effects • Full arousal not possible
than other sympathomimetics, e.g., metaproterenol. • Mental and physical activity diminished
The degree to which these medications stimulate the • Pain and deep tendon reflexes present
alpha, beta-one, and beta-two receptors, as well as the • Slow response to verbal stimuli
host response, influences the likelihood of producing
side effects. Comatose
(1:454–456), (2:580–584), (15:177–181), • Unconscious
(16:479–484). • No response to stimuli
• No voluntary movement
IIIC1a • Possible upper-motor neuron dysfunction (Babinski
80. D. The patient has achieved a volume of 2.1 liters, reflex present and hyperreflexia)
which is 60% of the preoperative goal of 3.5 liters (2.1 • No reflexes if deep or prolonged coma
liters/3.5 liters  100 = 60%). The preoperative goal
of 3.5 liters has not been met, however. The treatment In-depth neurologic assessment is generally beyond
should be continued to avoid possible post-operative the scope of the CRT, but he should be able to place a
complications. The pain around the incision site is nor- patient into one of these categories based on a physical
mal for this time frame in the course of the patient’s exam and review of the patient’s medical records.
healing process.
(1:301–302), (9:39–40).
(1:775–777), (16:529–532).
IIB1h(1)
IB5a 82. B. For a set oxygen concentration to be delivered to a
81. B. A simplified classification for determining the level patient, the flow rate from the oxygen device must
of consciousness of patients who are not fully alert is meet or exceed the patient’s peak inspiratory flow rate.
as follows: If the patient’s peak inspiratory flow rate surpasses that

Chapter 2: Pretest 65
 provided by an oxygen-delivery system, room air will IIIE1i(1)
dilute the set oxygen concentration. The following steps 84. C. With the ventilator settings established (V̇I 30
outline how to determine whether a given flow rate will L/min. and VT 500 ml), and with the patient assisting
meet or exceed the patient’s peak inspiratory flow rate. at a ventilatory rate of 24 breaths/min., this patient has
STEP 1: Calculate the patient’s inspiratory flow rate an inspiratory time (TI) of 1.0 sec. and an I:E ratio of
(V̇I ). 1:1.5. These values were determined as follows:

V̇T STEP 1: Convert the V̇I from L/min. to L/sec.

= V̇I
TI 30 L/min.
= 0.5 L/sec.
500 ml 60 sec./min.
= 500 ml/sec., or 0.5 L/sec.
1 sec.
STEP 2: Convert the VT from milliliters (ml) to liters.
STEP 2: Express 0.5 L/sec. in L/min. Because 60
500 ml
seconds equals one minute, then = 0.5 L
1,000 ml/L
(0.5 L/sec.)(60 sec./min.) = 30 L/min.
STEP 3: Divide the V̇ I by the air:oxygen ratio at 28% STEP 3: Calculate the inspiratory time (TI) by using
(air:O2 ratio at 28% is equal to 10:1). the following formula.

V̇ I flow rate required to deliver VT

= = TI
air:O2 prescribed FIO2 V̇I
0.5 L
= 1.0 sec.
30 L/min. 0.5 L/sec.
= 3 L/min.
10
1( ) STEP 4: Determine the TCT as follows.
60 sec./min.
An air:oxygen ratio of 10:1 at 3 L/min. will actually pro- = 2.5 sec./breath
vide a flow rate of 33 L/min. to the patient. For example: 24 breaths/min.
10 L/min. of air at 3 L/min. = 30 L/min. STEP 5: Subtract the TI from the TCT to obtain the
1 L/min. of oxygen at 3 L/min. = 3 L/min. expiratory time (TE).
The total flow rate received by the patient will be as 2.5 sec./breath (TCT)
follows: –1.0 second (TI)
30 L/min. of air 1.5 sec. (TE)
+ 3 L/min. of oxygen STEP 6: Calculate the I:E ratio.
33 L/min. of 28% oxygen TI TE
: = I:E
Therefore, 3 L/min. of source gas flow is the minimum TI TE
flow rate that will provide an adequate flow to the pa-
tient who is receiving 28% oxygen via a Venturi mask. 1.0 sec. 1.5 sec.
: = 1:15
The calculation represents an average inspiratory flow 1.0 sec. 1.5 sec.
rate. For safe measure, a total flow rate of greater than
This inspiratory time and I:E ratio are unacceptable for
40 L/min. would be appropriate.
a COPD patient. Emphysematous lungs have a de-
(1:751–754), (5:77, 82), (13:52–55). creased elastic recoil, and small airways collapse. A
longer expiratory time is needed to avoid air trapping,
IIB2f(1) which is occurring with this patient. The air trapping is
83. D. Oropharyngeal airways are contraindicated in pa- manifested as an increased WOB and as auto-PEEP.
tients who are not comatose because they will gag, Lengthening the expiratory time can be accomplished
vomit, and possibly aspirate their gastric contents. If by increasing the peak inspiratory flow rate to decrease
an airway continues to be needed, the nasopharyngeal the inspiratory time. Increasing the peak inspiratory
airway is tolerated well by conscious and semicon- flow rate to 45 L/min. would decrease the inspiratory
scious patients. Additionally, it facilitates nasotracheal time to 0.75 sec. and decrease the I:E ratio to 1:2.7.
suctioning, should that procedure become necessary. These values are borne from the calculations outlined
(1:647–648), (5:252–256), (13:158–159). here.

66 Chapter 2: Pretest
 STEP 1: Convert the V̇I of 45 L/min. to L/sec. To benefit from CPAP, the patient needs to be capable of
maintaining an adequate alveolar ventilation to achieve a
45 L/min.
= 0.75 L/sec. near-normal arterial PCO2. The primary problem would
60 sec./min be the patient’s inability to oxygenate without the ad-
STEP 2: Calculate the TI. ministration of supplemental oxygen. Therefore, nasal or
mask CPAP would be beneficial as a therapeutic inter-
0.50 L vention in acute hypoxemic ventilatory failure.
= 0.67 sec.
0.75 L/sec. Patients who cannot ventilate adequately via their own
efforts to maintain a near-normal arterial PCO2 are not
STEP 3: Compute the TCT. candidates for CPAP. Likewise, those who are heavily
60 sec./min. sedated will not likely benefit because of the failure to
= 2.5 sec./breath maintain spontaneous breathing. The patient who is
24 breaths/min.
about to receive CPAP should be alert and cooperative.
STEP 4: Determine the TE. Light sedation may be necessary at times.
2.50 sec./breath (TCT) Other situations that may respond well to nasal or
– 0.67 sec. (TI) mask CPAP include
1.83 sec. (TE) • a person who is anticipated to improve or recover in
STEP 5: Calculate the I:E ratio. a few days
• a patient who has diffuse, acute pulmonary disease
0.67 sec. 1.83 sec. • a patient who requires positive pressure levels less
: = 1:2.7
0.67 sec. 0.67 sec. than 10–15 cm H2O
• a person who generally does not have multi-organ
(1:860, inside back cover), (15:901–906). system problems

IA1f(3) (1:864–866, 1130), (15:733), (16:617, 900).

85. B. Hyperactive airways disease involves broncho-
spasm, bronchial mucosal edema, and hypersecretion. IIB1e(1)
Each of these mechanisms increases airway resistance 88. A. By definition, a pressure-cycled ventilator termi-
by reducing the radius of the obstructed airways. Air- nates inspiration when a preset pressure is generated in
way resistance is the difference in pressure between the patient-ventilator system. Despite the PIP remain-
the ends of the airways divided by the flow rate of gas ing virtually constant, the tidal volume received by the
moving through the airways, according to the formula, patient will vary according to the changes in the pa-
Raw = DP ÷ V̇. An inverse relationship exists between tient’s lung characteristics. In other words, the tidal
airway resistance (Raw) and flow rates (V̇). If the Dri- volume delivered will fluctuate in response to changes
ving Pressure (DP) is constant, a reduced flow rate in- in the patient’s lung compliance and airway resistance.
dicates an increase in airway resistance. In the event that bronchospasm develops while a patient
(1:202–204), (16:320, 323, 573). receives mechanical ventilatory support from a pres-
sure-cycled ventilator, a number of ventilatory changes
IIIG2c will occur in response to this increase in airway resis-
tance. First, the pressure generated to overcome airway
86. C. When a patient who has disseminated intravascular
resistance will increase (i.e., a greater segment of the
coagulopathy (DIC) (or any coagulopathy for that mat-
peak inspiratory pressure will be used to overcome the
ter) is about to have a fiberoptic bronchoscopy per-
increased airway resistance in the lungs than that which
formed for the purpose of obtaining a lung biopsy, the
contributed to maintaining alveolar distention following
following tests need to be performed.
a lung volume change). Next, because more pressure is
• an activated partial thromboplastin time required to inflate the lungs, the PIP is achieved earlier.
• a prothrombin time Consequently, inspiration is terminated earlier. Last, be-
• a bleeding time cause inspiration terminates earlier, the patient’s inspi-
ratory time (TI) and tidal volume (VT) both decrease.
(1:622), (16:287–289).
Based on the direct relationship between the tidal vol-
ume and inspiratory time shown as follows, the peak in-
IIA1f(3) spiratory flow rate will either remain the same or
87. C. CPAP is the application of supra-atmospheric pres- decrease. The peak inspiratory flow rate will remain
sure to a patient’s airways throughout the entire ventila- constant if the tidal volume and inspiratory time de-
tory cycle while the patient is spontaneously breathing. crease proportionately. Otherwise, it will decrease.

Chapter 2: Pretest 67
 VT tidal volume and an FIO2 that will be more appropriate
= TI for patients with airway resistance or lung-compliance
V̇I
problems. The 18-year-old patient suffering from nar-
or cotic overdose would most likely have stable airways
VT and lung compliance; therefore, this patient would be
= V̇I the most suitable candidate to be adequately ventilated
TI via a pressure-cycled ventilator.
Pressure-cycled ventilators ordinarily are not reliable (1:845), (5:372), (13:371).
for delivering a constant volume in many clinical sit-
uations. Therefore, their use should be limited to pa-
tients whose lungs are normal but require ventilatory IIIE1e(1)
assistance. For example, patients with neuromuscular 91. B. A simple oxygen mask is designed to accommodate
disease and patients who require short postoperative a source flow of 5–10 L/min. Exceeding the flow limit
ventilatory support can generally be accommodated of a device may cause inadequate humidification of the
by this form of mechanical ventilation. Examples of source gas. When the upper respiratory tract dehy-
pressure-cycled ventilators are the Bennett PR-1 and drates, it is not uncommon for patients to complain of
PR-2 and the Bird Mark 7 and 8. upper airway drying, irritation, and non-productive
(1:845), (5:372), (13:371). coughing. An additional factor in this situation may be
the water level in the humidifier. If it is low, even more
dry gas will be delivered to the patient’s airway.
IIIE1h(1)
89. A. Difficulty in clearing secretions may result from In this case, the CRT should ensure a proper water level
their tenacity and amount or from the patient’s inabil- in the humidifier, lower the oxygen flow rate, and mon-
ity to generate an effective cough. Difficulty in clear- itor the patient. At the same time, the CRT must evalu-
ing secretions is the primary indication for suctioning. ate the patient’s ventilatory status (i.e., tidal volume,
This patient will benefit from optimal positioning (i.e., ventilatory rate, and ventilatory pattern) to ensure that
semi-Fowler’s position, with the patient’s neck in mild this patient meets the criteria for a low-flow oxygen-
extension), as well as more frequent suctioning ac- delivery device (simple mask). If this patient has a high
companied with instillation of irrigation solution to di- minute ventilation (VT  f = V̇E ), the FIO2 delivered by
lute and mobilize the secretions. Increasing the the simple mask—even with the flow rate reduced—
duration of application of suction is not warranted. The will be lower than the patient needs. For a low-flow
duration of each suctioning event should be limited to oxygen-delivery system, as the minute ventilation in-
10–15 seconds. creases, the FIO2 decreases. The converse of this state-
ment is also true. Additionally, the CRT needs to check
(“Clinical Practice Guidelines: Endotracheal Suction- the physician’s orders for this patient’s oxygen, because
ing of Mechanically Ventilated Adults and Children the order may be inappropriate.
with Artificial Airways,” 1993, Respiratory Care,
38(5), pp. 500–504), (Respiratory Care, 1992, 37(8), (1:745, 749–750), (16:386–387).
pp. 898–901). (1:616), (16:600–601).
IIIE1i(1)
IIIC1c
92. D. To decrease the patient’s PaCO2 from 32 torr to 25
90. B. A pneumatically powered, pressure-cycled ventila- torr, an increase in minute ventilation is indicated. This
tor will deliver varied tidal volumes depending on PaCO2 adjustment can be accomplished by increasing
changes in the patient’s pulmonary mechanics. Either either the tidal volume or the ventilatory rate. Because
increases in airway resistance or decreases in lung the patient’s IBW is unknown, increasing the tidal vol-
compliance will cause the delivered tidal volume to ume would be justified as long as the new setting is
decrease. Both the five-year-old asthmatic patient and within the range of 10–15 ml/kg. Once a preset tidal
the 66-year-old emphysema patient are highly suscep- volume of 15 ml/kg is achieved, the ventilatory rate
tible to changes in airway resistance—the asthmatic should be increased if the PaCO2 remains above the
patient from bronchoconstriction, and the emphyse- desired level. Until the effects of anesthesia wear off,
matous patient from collapse of peripheral airways. however, the patient will not benefit from the ability to
initiate a preset tidal volume or spontaneous breaths
The 20-year-old with bilateral pulmonary contusions from the ventilator in either the assist-control or SIMV
will likely have decreased lung compliance. Also, pres- mode.
sure ventilators usually lack precise oxygen controls.
Volume-cycled ventilators, however, deliver a precise (1:978–979).

68 Chapter 2: Pretest
IIIB2a The CRT must ensure an adequate inspiratory flow
93. C. Coarse rhonchi are produced by secretions in the rate without increasing expiratory WOB. If the patient
airways. If the patient is unable to expectorate them requires high levels of CPAP and high inspiratory flow
himself, percussion and postural drainage are helpful rates via a mask, the CRT should recommend the in-
in mobilizing the secretions. sertion of a nasogastric tube to help combat gastric in-
sufflation.
(1:313), (9:63–64), (15:788–790), (16:173–174).
The CRT should monitor the patient’s SpO2 carefully. If
IIB2a(3) a pulmonary artery catheter is in place, determination of
the shunt fraction before and after CPAP application
94. C. CPAP masks are indicated whenever the patient is would help determine the therapy’s effectiveness. In ad-
having difficulty oxygenating while still having a nor- dition, the CRT should monitor the patient’s C.O. to de-
mal or decreased PaCO2. CPAP masks are frequently termine whether the C.O. falls following the application
beneficial in the treatment of refractory hypoxemia of CPAP.
caused by physiological shunting. By raising the mean
airway pressure, the alveoli no longer collapse during (1:865–866, 1131–1132), (16:616–618, 900).
exhalation; as a result, the shunt fraction frequently de-
creases. IIID8
The CRT must ensure that the delivered flow of 95. C. A full cylinder holds 2,200 psig. The cylinder fac-
blended gas is adequate to meet the patient’s inspira- tor for an E tank is 0.28 L/psig. Once the pressure-
tory demands. If that is not the case, carbon dioxide re- gauge reading and the cylinder factor are known, the
breathing becomes a problem, pressure fluctuations cylinder’s flow duration can be determined.
greater than  2 cm H2O occur, and the patient’s oxy- STEP 1: Use the following formula to calculate the
genation status becomes more periled. The following duration of flow (min.).
pressure-time and volume-pressure diagrams (Figure
2-16) illustrate the problems that may be encountered gauge pressure (psig) × cylinder factor (L/psig)
flow duration =
with CPAP. (min.) flow rate (L/min.)
The next two graphics (Figure 2-17) illustrate inade- (2,200 psig –500 psig)(0.28 L/psig)
quate flow from the CPAP device. Notice the large in- =
3 L/min.
spiratory pressure swings associated with this condition.
(1,700 psig)(0.28 psig–1)
The final two graphics (Figure 2-18) demonstrate the =
result of excessive gas flow rates into a CPAP system. 3 min.
This condition increases expiratory work and increases = 158 min.
the chance of gastric insufflation.

Inspiratory Work Expiratory Work

A. B.
Pressure

Volume

Exhalation

Inhalation

Figure 2-16: (A) Represents pressure changes for two spontaneous breaths during CPAP. Note the
little pressure change during inhalation and exhalation. (B) Illustrates WOB encountered with CPAP.
The area within each curve is associated with inhalation (stripes) and exhalation (white). Note that little
WOB occurs during inhalation and exhalation when the CPAP flow rate is appropriate. Patient exhaling
through the exhalation valve causes a slight degree of expiratory work.

Chapter 2: Pretest 69
 Increased Inspiratory Work

Pressure (cm H2O) A. B.

Volume
20

Exhalation
10

0 Inhalation
Time 10 cm H2O CPAP

Figure 2-17: (A) Indicates a large pressure drop during exhalation, resulting from inadequate gas flow.
Note that the expiratory curve appears as if the flow rate is accurate. (B) Reflects the increased WOB as-
sociated with an inadequate flow rate. Note that the inspiratory WOB is increased, while the expiratory
WOB remains normal.

Expiratory Work

A. B.
Pressure (cm H2O)

Volume

20
Exhalation

10

Inhalation
0
Time 10 cm H2O CPAP

Figure 2-18: (A) Illustrates a slight pressure drop during inhalation; consequently, the inspiratory WOB is
normal. Note the higher pressure developed during exhalation, indicating an increased WOB during this
phase. The excessive flow rate causes high back pressure, which the patient must overcome during exha-
lation. (B) The WOB during inhalation is normal, whereas the excessive flow rate causes an increased
WOB during exhalation.

STEP 2: Convert the cylinder flow duration to hours STEP 3: Determine the time at which the patient must
(hr). return to her room before her oxygen supply
is depleted.
158 min.
= 2.63 hr, or 2 hr and 38 min.
60 min./hr 11 A.M. + 2 hr and 38 min. = 1:38 P.M.
(1:722), (5:40), (13:46), (16:356).

70 Chapter 2: Pretest
IIIA2a ∆SO2
96. C. Recording the specific modality, date, and time of 3.5%
100
any therapy that is administered is important. Some

Percent Oxygen Saturation

type of solution must be placed in the nebulizer to
avoid drying of the airway. This solution could be a 80
bland substance, such as normal saline, or it could in- ∆SO2
clude a medication, such as a bronchodilator. Because 26%
the primary purpose of IPPB is to assist the patient in 60
taking a breath deeper than spontaneous breathing can
provide, it is considered essential to document the vol- 40
ume achieved. Normally, the pressure required to
achieve that volume is also documented. Noting the ∆PO2 ∆PO2
pressure and volume allows the CRT to monitor both 20 20 mm 20 mm
the effectiveness of the therapy and the patient’s day- Hg Hg
to-day progress. The sensitivity—or amount of nega-
tive effort needed to start inspiration—is normally set 0 20 40 60 80 100 120
so that –1 to –2 cm H2O is needed. This amount of ef-
fort does not need to be documented, because it is al- Oxygen Tension (mm Hg)
ways set at this level to avoid increasing the patient’s Figure 2-19: A PO2 of the same magnitude on the flat
WOB. and steep portions of the O2Hb dissociation curve results in
a differing SO2. For example, a 20-mm Hg change (80–100
(1:778–781), (16:532–533). mm Hg) on the flat segment of the curve corresponds with a
SO2 of 3.5%, whereas a 20-mm Hg change (30–50 mm
Hg) reflects a SO2 of 26.0%.
IA1f(5)
97. D. A pulse oximeter incorporates a noninvasive spec-
trophotometer to determine the relationship between
oxyhemoglobin and reduced hemoglobin. An oximeter
is easy to apply and maintain. Numerous factors affect As an example, note that a 20 mm Hg PO2 change
the accuracy of a pulse oximeter, however, including on the flat portion of the oxyhemoglobin dissociation
the following factors: curve corresponds with an oxygen saturation change
of 3.5%, whereas a 20 mm Hg PO2 along the steep
• carboxyhemoglobin segment is associated with a SO2 of 26.0%.
• methemoglobin
• fetal hemoglobin (1:359–363), (5:319–322), (13:252–257),
• motion (16:310–312, 400–401).
• vascular dyes
• ambient light (especially bright lights) IIIC2c
• dark skin pigmentation
98. C. Patients with unilateral lung disease may experi-
• nail polish
ence severe hypoxemia when placed with the involved
The presence of carboxyhemoglobin and/or methemo- lung in a dependent position. Gravity will increase
globin will cause an overestimation of the SaO2. blood flow to the poorly ventilated portion of the lung,
resulting in a worsened mismatch of ventilation and
Another problem with pulse oximetry is that at high
perfusion. Perfusion would exceed the amount of ven-
PO2s, the oxyhemoglobin dissociation curve is rela-
tilation, producing an intrapulmonary shunt-like ef-
tively flat. Consequently, large changes in the PaO2,
fect. Intrapulmonary shunting is defined as capillary
which would indicate a dramatic worsening of lung
shunt plus shunt effect (venous admixture).
function, would not be detected by the pulse oximeter.
If the patient’s PaO2 falls on the steep portion of the A simple way to remember how to position patients
curve, however, small changes in oxygenation will with single-lobe or multi-lobe pneumonia, unilateral
cause large changes in saturation. In this case, the lung contusion, or unilateral atelectasis is to apply the
pulse oximeter would be a useful, noninvasive method expression, “Down with the good lung.” There are ex-
to monitor a patient’s oxygenation status. ceptions to this rule, however. In cases of massive on-
going hemoptysis, placing the bad lung down may
The diagram of the oxyhemoglobin dissociation curve
help prevent flooding of the good lung with blood.
(Figure 2-19) demonstrates changes in oxygen satura-
Similarly, when large abscesses exist, it may be advis-
tion (SO2) along the steep and flat portions of the curve
able to place the involved area in a dependent position.
in response to the same magnitude of change in the dis-
solved oxygen tension (PO2). (Respiratory Care, 1987, p. 489), (15:735–736).

Chapter 2: Pretest 71
IIB1a(2) Therefore, the adaptor that has the largest diameter
99. A. The oxygen appliance shown here is a Venturi (less narrow restriction) will render the higher FIO2.
mask. Venturi masks operate according to the principle Figure 2-20 provides air:O2 ratios along with the total
of air entrainment. Source gas (oxygen) flows through delivered flow and FIO2, based on the orifice size of
the device and encounters a narrowing or restriction. the adaptor.
As the oxygen flow meets the restriction, the lateral (1:754), (5:52–54), (13:76–77), (15:883–885),
wall pressure at that point decreases, and air is en- (16:390–391).
trained to dilute the oxygen. The degree to which the
oxygen is diluted depends on the amount of room air IIIF1
entrained at the restriction. The amount of room air en-
100. A. Evaluating the effectiveness of external cardiac com-
trained, in turn, is determined by the diameter of the
pressions is best accomplished by palpating either the
restriction or the degree to which the adaptor is nar-
carotid or femoral pulse. When changing personnel to
rowed.
assume CPR responsibilities, CPR efforts must not be
For example, the less narrow the restriction, the less interrupted or compromised. The person who is, about
the lateral wall pressure decreases—permitting less to take over performing external cardiac compressions,
room air entrainment. A higher FIO2 will be delivered. must evaluate the effectiveness of the compressions be-
If a more narrow (smaller diameter) restriction is en- fore assuming that role. The person who is actually ap-
countered, more room air is entrained, and thus the plying the external cardiac compressions shouts out the
FIO2 is lowered. following command: “We will change next time.” Each

Adaptor Orifice Air:O2 Ratio Total Flow FIO2

25:1 144 lpm 0.24

10:1 44 lpm 0.28

7:1 48 lpm 0.31

5:1 48 lpm 0.35

3:1 32 lpm 0.40

Figure 2-20: Venturi mask adapters with corresponding air O2 ratios FiO2s

72 Chapter 2: Pretest
 word of this command uttered by a rescuer corresponds The patient receiving NPPV must not be intubated. To
with one cardiac compression. This command also en- begin, a nasal mask is generally used. If the mask leaks
ables the reliever to become ready to assume compres- excessively, a full face mask must be applied. If a full
sions without interrupting the CPR procedure. The face mask does not enable satisfactory application of
person who is relieved of performing the compressions NPPV, the patient must be intubated and mechanically
will then provide the ventilations if indicated. ventilated.
(1:640), (15:1118). (1:895, 982, 1122, 1128), (10:192, 399), (16:616, 1137).

IIIE1f IC2a
101. C. The best schedule would be to give the albuterol ther- 104. C. If pulmonary function tests indicate an obstructive
apy, followed by postural drainage and chest percussion, impairment is present (FEV1% less than 70%), a before-
at 7 A.M., 11 A.M., 3 P.M., and 7 P.M. The Atrovent could and-after bronchodilator study is warranted to assess
then be given at 9 A.M., 1 P.M., 5 P.M., and 9 P.M. to ensure whether relief of airflow obstruction is possible (i.e., re-
that the patient was receiving a bronchodilator every versible airflow obstruction). This test involves having
two hours from 7 A.M. to 9 P.M. Albuterol is a preferen- the patient perform a second set of three FVC maneu-
tial beta-two bronchodilator, whereas Atrovent is a vers following administration of a beta-adrenergic drug.
cholinergic blocking agent. Both could be safely given Two measurements may be examined for improvement:
at the same time, however, if desired. the FEV1 and the FEF25%–75%. Most authorities rely heav-
ily on changes in the FEV1 and discount the importance
(1:574, 578), (8:115, 135–137).
of the FEF25%–75% in this evaluation. References vary as
to what level of improvement would constitute re-
IIIE1g(1) versible airflow obstruction. Generally, an increase in
102. A. A Passy-Muir valve is a one-way speaking valve for the FEV1 greater than or equal to 15%–20% is consid-
certain tracheostomized and ventilator patients. The ered significant for reversible airflow obstruction. This
valve is designed for patient communication. The degree of change supports a diagnosis of asthma and
valve remains closed except when the patient inhales, suggests that bronchodilator therapy would be useful in
at which time it begins to close at the end of inspira- the treatment of the airflow obstruction. Failure to get
tion, providing a seal. The valve remains closed this level of improvement, however, does not rule out
throughout exhalation, allowing for such conditions as the diagnosis of asthma or the use of beta-adrenergic
restoration of physiologic PEEP, increased pressures drugs. Many factors account for less-than-significant
for swallowing, and increased volume for speech. improvement in a particular before-and-after bron-
Following attachment of a Passy-Muir valve, the CRT chodilator test. The formula for determining the percent
should evaluate breath sounds and the patient’s ability improvement of the component of the FVC that is mea-
to cough, speak, and ventilate. In fact, the CRT must sured is shown below.
not leave the patient alone until the patient has demon- % improvement =
strated the ability to ventilate adequately with the postbronchodilator FEV1 – prebronchodilator FEV1
Passy-Muir valve in place.
prebronchodilator FEV1
(5:268), (13:178), (15:569–570). × 100

IIB2e(2) (1:373), (6:51), (15:465–466), (11:306).

103. D. NPPV is an excellent alternative for certain pa-
IIIE1c
tients, as opposed to immediately intubating them and
establishing conventional mechanical ventilation. Pa- 105. B. Ninety percent (90%) of incentive spirometry com-
tients who have been successfully treated with NPPV pliance is patient motivation. Pediatric patients can of-
include those with chronic ventilatory failure caused ten use an adult incentive spirometer, but frequently
by (1) chest wall deformities, (2) neuromuscular dis- respond better when the device has accessories that are
ease, (3) COPD, (4) cystic fibrosis, or (5) bronchiecta- designed to build motivation for the procedure. A pe-
sis. Patients with acute ventilatory failure who respond diatric device and a discussion with the patient may be
favorably to NPPV include those with (1) ARDS, (2) all that this child needs to comply with the physician’s
pneumonia, (3) cardiologic pulmonary edema, (4) orders. Discontinuing the therapy without working
heart failure, (5) obstructive sleep apnea, (6) asthma, with the child would be counterproductive.
or (7) COPD (acute exacerbation). (15:1050).

Chapter 2: Pretest 73
IIIA1b(3) tion. This characteristic of the Bourdon gauge flow
106. D. Examination and documentation of the gross physi- meter makes it suitable for transport situations where
cal characteristics of sputum are important for several the E cylinder often needs to be placed in a horizontal
reasons. First, there is often a strong relationship be- position. Therefore, the CRT does not need to do any-
tween the type of sputum and the disease or condition thing, because this situation is acceptable.
that is present. For example, patients with bronchiecta- (1:731), (5:48–50), (13:57–58), (15:868), (16:359–360).
sis frequently cough up large amounts of foul-smelling
(fetid) sputum that separates into three layers, whereas IIIB2c
asthmatics often produce stringy or mucoid sputum.
109. B. Ideally, when IPPB is administered, tidal volumes
Fresh purulent sputum is usually yellow. Second, the
should be monitored and appropriate goals should be
effectiveness of therapy can be determined by exami-
set. If on initial assessment the patient’s measured vi-
nation of the sputum. For example, tenacious, dehy-
tal capacity exceeds 15 ml/kg of body weight, IPPB is
drated mucus might change in consistency as a result of
not indicated, because the patient is capable of taking
humidification or aerosol therapy. Color, quantity, con-
a sufficiently deep breath on his own. An alternative
sistency, presence of blood, and odor of sputum are the
means of aerosolizing albuterol would be more appro-
most important identifying characteristics that are use-
priate in this case.
ful in evaluating the patient’s condition or the outcome
Performing CPT one hour before the gavage feeding is
of a particular treatment.
the same as two hours after the feeding.
(1:299), (16:166, 175).
(1:778–781), (15:846), (16:532–533).

ID1d IIIC1c
107. B. Quite often, premature ventricular contractions 110. A. The assist-control mode of mechanical ventilation
(PVCs) are innocuous cardiac dysrhythmias. They do enables the patient to control the ventilatory rate as
reflect a varying degree of myocardial irritability, how- long as his spontaneous rate is greater than the ma-
ever. PVCs arise from an ectopic focus in the ventri- chine’s rate. If not, the mode switches to control. As the
cles (i.e., a spontaneous depolarization). When these ventilatory rate fluctuates, changes in the PaCO2 and
cardiac events increase in frequency (usually more acid-base status occur. As the patient’s ventilatory rate
than 6 PVCs/min.), and when they elicit patient com- increases, mean intrapulmonary pressures increase
plaints, aggressive therapy is indicated. Antidysrhyth- (which may, in turn, increase the mean intrathoracic
mic medications (e.g., procainamide and/or lidocaine) pressure and decrease venous return and C.O.).
are often administered I.V. Oxygen therapy is also in-
dicated from the standpoint of reducing the heart’s (1:848), (5:386–387), (13:363–364).
work. PVCs can cause the cardiac rhythm to deterio-
rate to ventricular tachycardia (and ultimately, to ven- IIIA1d
tricular fibrillation). The belief is that the risk of these 111. A. When CPT is ordered for a neonatal or pediatric pa-
lethal dysrhythmias can be reduced if the myocardial tient, it is essential that the treatments be coordinated
oxygen consumption is decreased. Therefore, the ad- with the patient’s feeding schedule. Because of the risk
ministration of a nasal cannula at 1–2 L/min. (FIO2 of regurgitation and aspiration, CPT should be per-
0.24–0.28) should provide supplemental oxygen that is formed before the feeding. If this coordination is not
sufficient enough to reduce the work of the my- possible, at least 1–2 hours should have elapsed after
ocardium. The other forms of oxygen therapy offered the feeding before CPT is conducted. The CRT should
here would provide an FIO2 that exceeds the patient’s coordinate schedules with the nursing staff to accom-
requirements. If there is documented hypoxemia, plish this scheduling sequence.
however, these other forms of oxygen delivery and
their higher FIO2s may be indicated. (15:1047).

(1:330–331), (9:187, 188), (14:194), (16:864). IC2c

112. A. Neonatal blood, and particularly premature infant
IIB2h(3) blood, will often have significant levels of fetal hemo-
108. D. A Bourdon gauge is a pressure gauge that is some- globin. The absorption characteristics of fetal hemo-
times used as a flow-metering device. Although the globin are similar to those of carboxyhemoglobin
Bourdon gauge used as a flow meter is not back-pressure (COHb). Therefore, when fetal hemoglobin is present,
compensated, the flow indicator on the gauge is not af- the COHb values will be falsely elevated, and the SaO2
fected by position (i.e., gravity). The gauge will indicate values will be erroneously low.
the same flow rate in either a vertical or horizontal posi- (1:360, Table 16-6), (4:286).

74 Chapter 2: Pretest
IIIE1h(2) mated from this six-second (30 large horizontal
113. C. A closed-suction system can be used to facilitate blocks) ECG strip. The six-second ECG tracing repre-
continuous mechanical ventilation and oxygenation sents one-tenth of a minute’s electrophysiologic activ-
during the suctioning event. This system permits suc- ity. Therefore, multiplying the two PVCs that appear
tioning without having to disconnect the patient from on this strip by 10 provides an estimate of the number
the ventilator, thereby maintaining PEEP and reducing of PVCs occurring each minute (i.e., 2 PVCs  10 =
the potential for deterioration in oxygenation and he- 20 PVCs).
modynamic status. The PVCs appearing on the six-second tracing may
(“Clinical Practice Guidelines: Endotracheal Suction- represent a relatively random occurrence. Conse-
ing of Mechanically Ventilated Adulls and Children quently, a longer time interval should be observed to
with Artificial Airways,” 1993, Respiratory Care, obtain a more precise count. An isolated PVC is con-
38(5) pp. 500–504). (1:619), (5:281), (13:183). sidered to be innocuous. When PVCs become numer-
ous and frequent, however, they can be a harbinger of
IIIG1c a serious dysrhythmia (i.e., ventricular tachycardia).
Therefore, in this situation, removing the suction
114. D. When a tracheotomy is being performed on a pa- catheter immediately is appropriate, because the my-
tient who is orally intubated, the endotracheal tube ocardium may become more irritable if suctioning is
should be removed immediately before the physician continued as more lung volume and oxygen are evac-
is about to insert the tracheostomy tube. uated. Adequate pre- and post-suctioning oxygenation
(1:601), (16:599). are essential to prevent precipitous arterial desatura-
tion. The cardiac tracing shown here, along with the
IIIB1a two PVCs, is a normal sinus rhythm at a rate of ap-
proximately 80 beats/min. Note the following tracing
115. C. In some patients, particularly obese ones, airway
(Figure 2-21).
obstruction persists even with mandibular traction. In-
sertion of an oropharyngeal airway can greatly facili- (1:619), (16:606).
tate maintenance of a patient’s airway. A pharyngeal
airway is especially useful during bag-mask ventila- IIIC2a
tion. The pharyngeal airway functions by separating 117. C. Auto-PEEP (intrinsic PEEP) frequently develops
the tongue from the posterior pharyngeal wall. The pa- during the mechanical ventilation of COPD and asth-
tient should be comatose because the oropharyngeal matic patients. The auto-PEEP develops as a conse-
airway can produce gagging and vomiting in an alert quence of air trapping and hyperinflation. The problem
or semicomatose patient. with auto-PEEP is that it occurs unrecognized unless
(1:647–648), (5:252–256), (13:158–159), (15:826). the exhalation port is occluded at the end of exhalation,
immediately before the ensuing inspiration. Performing
IIIE1h(1) this maneuver enables the pressure throughout the pa-
tient–ventilator system to equilibrate. Any PEEP (auto-
116. B. The patient in this situation is experiencing about
PEEP) that develops will register on the pressure
20 PVCs per minute. The number of PVCs is esti-

6 seconds

Normal sinus rhythm

2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

PVC PVC
Figure 2-21: Lead II ECG tracing showing two PVCs (arrows) and a normal sinus rhythm at 80 beats per minute.

Chapter 2: Pretest 75
 manometer. Similarly, ventilators (Siemens Servo STEP 2: Calculate the tidal volume (VT).
900C and Hamilton Veolar) that incorporate the expira-
V̇T = VE
tory-hold feature provide for the determination of auto-
PEEP. f

Auto-PEEP can produce the same physiological ef- 16.2 L/min.

fects as therapeutically applied PEEP (i.e., decreased 18 breaths/min.
venous return, decreased C.O., and barotrauma). In the
case of applied PEEP, the CRT monitors the patient = 0.9 L/breath
because these adverse effects are known. Because STEP 3: Obtain the TCT.
auto-PEEP is not readily detectable and the CRT does
not always consider its presence, however, it can pro- 60 sec./min.
= TCT
duce serious consequences during the course of patient f
care. Once auto-PEEP has been detected, a number of
60 sec./min.
approaches are available for managing this condition. = 3.33 sec./breath
If the auto-PEEP develops because of airflow obstruc- 18 breaths/min.
tion, one approach includes: (1) CPT, (2) bronchodi-
latation, and (3) tracheobronchial suctioning. Another STEP 4: Determine the inspiratory time (TI).
approach in this situation entails lengthening the expi- TI = TCT  TI%
ratory time by either decreasing the ventilatory rate = (3.33 sec.)(0.33)
and increasing the tidal volume or by decreasing the = 1.09 sec.
inspiratory time by increasing the peak inspiratory
flow rate and using less compliant ventilator tubing. In STEP 5: Compute the expiratory time (TE).
addition to these efforts, the application of therapeutic
PEEP has been shown to reduce the auto-PEEP. The TCT – TI = TE
mechanism whereby applied PEEP eliminates auto- 3.33 sec. 2 1.09 sec. = 2.24 sec.
PEEP is by improving gas distribution and reducing
the transpulmonary pressure (intrapleural pressure mi- STEP 6: Calculate the I:E ratio.
nus intra-alveolar pressure) gradient during exhalation.
TI TI
Other mechanisms that have been clinically applied to : = I:E
eliminate auto-PEEP include TI TE

• using an ET tube with a larger internal diameter 1.09 sec. 2.24 sec.
: = 1:2
• normalizing the patient’s pH by administering bicar- 1.09 sec. 1.09 sec.
bonate to correct a metabolic acidosis
The patient’s expiratory time can be lengthened by (1)
• permitting the arterial PCO2 to increase within the
decreasing the tidal volume, (2) increasing the inspira-
range of 50 and 60 torr by decreasing the ventilatory tory flow rate, and/or (3) decreasing the ventilatory
rate and normalizing the pH rate. In fact, the tidal volume that this patient is re-
• applying SIMV at a low ventilatory rate ceiving is too high (i.e., 900 cc  60 kg = 15 cc/kg).
The patient presented here could likely respond favor- Patients with COPD should receive a tidal volume
ably to approaches other than instituting applied within the range 8–12 cc/kg to help alleviate air trap-
PEEP. Decreasing this patient’s I:E ratio may reduce ping.
the auto-PEEP by lengthening the expiratory time. An (1:828, 860, 917), (15:901–908), (16:318, 621, 625, 684).
inspection of this patient’s I:E ratio reveals that the ra-
tio is approximately 1:2. Note the following calcula-
IIB1b
tions:
118. C. The component (labeled A) in the gas-delivery sys-
STEP 1: Convert the peak inspiratory flow rate (V̇I) tem functions as a water trap to accept condensation
from L/min. to L/sec. that occurs throughout the circuitry from the humidi-
V̇I fier to the patient’s mask. The water-collection trap
= L/sec. must be placed along the most gravity-dependent por-
60 sec./min. tion of the circuitry.
50 L/min.
= 0.83 L/sec. If water (condensate) is allowed to accumulate in the
60 sec./min. tubing, it can increase the airway resistance in the tub-

76 Chapter 2: Pretest
 ing, thereby reducing the efficiency of the nebulizer. If An empyema, depending on its size, usually requires
enough water is built up in the system, the FIO2 that antibiotic treatment and drainage via chest tubes or
the patient would receive would be greater than that di- thoracentesis.
aled on the nebulizer. The increased FIO2 is caused by
(1:479, 480), (15:356, 765–766, 1092), (16:214).
the back-pressure on the room air entrainment at the
Venturi (air-entrainment port). Less room air is en-
trained under increased back-pressure conditions. The IIIC2c
total flow rate will also be reduced. Similarly, the wa- 122. C. If a mechanically ventilated patient is being endo-
ter must be emptied regularly to prevent water from tracheally suctioned with a closed-suction catheter
building up in the tubing and causing back pressure system, there is no need to disconnect the patient from
from increasing in the system. the ventilator. This suction system is intended to re-
(1:671–672), (13:102). duce the likelihood of the patient becoming severely
desaturated during the suctioning procedure. Although
IIIC1g the patient remains connected to the ventilator, the
119. D. The increase in the PIP is the result of the patient’s FIO2 should still be increased to 1.00 during the suc-
increased airway resistance. The history of asthma tioning procedure to further safeguard against this
suggests that a bronchodilator may be needed to over- complication. Ventilating the patient with 100% oxy-
come the bronchospasm that has caused the increased gen via a manual resuscitator is inappropriate under
airway resistance. Alupent is the brand name of the these circumstances, because the patient does not need
adrenergic bronchodilator metaproterenol. This drug is to be disconnected from the ventilator.
a powerful beta-two stimulant and will relax bronchial (1:619), (15:836–837), (16:605).
smooth muscle. Albuterol (generic name) goes by the
brand names of Proventil and Ventolin. Salbutamol is
the generic name in Canada for the same drug. IIB2m
Bronkosol is the brand name of the adrenergic bron- 123. B. A Bourdon gauge measures gas pressure across a
chodilator isoetharine, also elicits the desired effects. fixed orifice to a hollow, slightly coiled (hooked) cop-
per tube. As the pressure increases, the tip of the
(1:455, 854), (16:482, 483).
hooked tube extends outward or slightly straightens.
A needle is attached to the hooked tube via a gear
IIIE1g(1)
mechanism, causing the needle to rotate on a pressure-
120. D. The ET tube has likely slipped into the right-main- calibrated face. The Bourdon gauge is used to measure
stem bronchus. A sudden increase in pressure indicates pressure within compressed, medical gas cylinders.
this occurrence is an acute situation, not one that the The pressure within an ET tube cuff is too low to be
CRT noticed at the beginning of CPR. Lack of chest measured by a Bourdon gauge. An aneroid pressure
excursions on the left side of the chest indicates that manometer needs to be used. Therefore, the Bourdon
the ET tube may have bypassed the carina and slipped gauge must be replaced. A back-pressure, compen-
into the right-mainstem bronchus. A chest X-ray sated Thorpe tube is a flow metering device, not a
should be obtained to confirm the location of the dis- pressure-metering instrument.
tal end of the ET tube. Displacement of the ET tube
into the right-mainstem bronchus will cause atelectasis (1:731), (5:68), (13:57–58), (16:359–360).
to develop rapidly in the left lung.
(1:955, 960–Table 41-13), (10:259). IIIC1f
124. A. When adapting the Puritan-Bennett MA-1 ventila-
IIIB2a tor for continuous-flow IMV, the sensitivity must be
121. D. An empyema, or pyothorax, is the collection of pure turned to the OFF position so that the patient is unable
pus in the intrapleural space. An empyema develops as to cycle the machine into the inspiratory phase. The
a secondary suppurative process, frequently as a com- flow rate to the IMV reservoir bag should be adequate
plication of bacterial pneumonia. Therefore, because an so that it meets the patient’s inspiratory flow demands.
empyema is not associated with airway blockage, it The gas flow rate through a continuous-flow IMV sys-
does not lend itself to be treated via CPT. Chest physio- tem must also be high enough to prevent the reservoir
therapy (postural drainage, vibration, and percussion) is bag from collapsing. Similarly, when the continuous
applied to patients who have excessive tracheobronchial flow is sufficient for the patient’s needs, a one-way
secretions as an attempt to promote bronchial hygiene. valve enabling the patient to inspire atmospheric air
The primary process (i.e., the condition that is responsi- will remain closed. The purpose of this one-way valve
ble for an empyema) may be treated with CPT. is to enable the patient to entrain atmospheric air into

Chapter 2: Pretest 77
 the IMV system in the event that the patient’s inspira- would place the patient on her right side, one-quarter
tory demands exceed the gas flow provided by the sys- turn from supine, in a slight Trendelenburg (head-
tem (or if the system fails). If the one-way valve does down) position.
not open when the patient needs to breathe beyond the
(1:166, 800), (16:120, 121, 514).
limits of the continuous-flow system, large negative
pressures will register on the system’s pressure gauge.
IIIA2b(1)
(1:860–862), (10:197–198), (13:632–634), (15:1053). 128. C. The primary stimulus to breathe for some patients
with chronic hypercapnia and hypoxemia is the hy-
IIB1f(4) poxic drive mechanism of the peripheral chemorecep-
125. B. The equipment that would be useful to have avail- tors (carotid and aortic bodies). Excess administration
able when preparing to perform orotracheal intubation of oxygen to these patients results in increased carbon-
on an adult patient includes: (1) a stylette (wire guide) dioxide retention, which has a narcotic effect on the
for difficult intubations, (2) stethoscope, (3) manual central nervous system. In general, it is desirable to
resuscitator and mask, (4) lubricating jelly, (5) topical maintain the PaO2 of these patients between 50 and 60
anesthetic, (6) tape, (7) three different sizes of ET mm Hg. This dissolved oxygen level would result in
tubes, (8) two laryngoscope handles and assorted oxygen saturations of about 90%. Oxygen concentra-
blades—Miller (straight) and McIntosh (curved), (9) tions of approximately 24%–28% delivered by an en-
oropharyngeal airways, (10) Yankauer suction (tonsil- trainment mask or low flow rates via a nasal cannula
lar) tube, (11) suction catheters, and (12) oxygen- are usually used with patients who are known or sus-
delivery equipment. pected of breathing via their hypoxic drive. The poten-
tially harmful effects of oxygen should never prevent
(1:594).
its use when oxygen is indicated. History, physical ex-
amination, blood gas analysis, and close observation
IB5a are needed to safely administer oxygen to patients with
126. D. When interviewing the patient, particularly about COPD.
sensitive issues, the best type of question to use is an
open-ended type. This form of question encourages a (1:287–290), (16:130).
patient to answer more fully and enables the patient to
choose words that are more familiar or less threatening IIIG1e
to him. Also, the CRT should avoid using words that 129. B. The following equipment preparations are neces-
may have a negative connotation and simply inquire sary before endotracheal intubation is performed.
about the patient’s symptoms or how he is feeling.
• Assemble all suction equipment.
The interrogative statements, “Are you depressed?” • Establish the appropriate suction pressure.
and “Do hospitals scare you?” are yes-no types of • Attach the laryngoscope blade to the handle.
questions. They also contain words such as depressed • Test the light source.
and scare, which have negative connotations to some • Ensure that the brightness of the laryngoscope bulb
people. These types of questions also have less chance is appropriate.
of surfacing the patient’s feelings. The questions, • Test the endotracheal tube cuff for leaks.
“What medications are you taking for nerves?” and • Obtain three different endotracheal tube sizes (ex-
“Have you ever had emotional problems in the past?” pected size, one size larger than the expected size,
are also yes-no type inquiries. These types of questions and one size smaller than the expected size).
often confuse and frustrate the patient. The question, • Lubricate the endotracheal tube.
“How are you feeling about being in the hospital?” is
The stylette, if used, is not lubricated; rather, it is sim-
an appropriate interrogative statement to pose, because
ply placed inside the endotracheal tube to make the
it is open ended. Likewise, it employs nonthreatening
tube somewhat rigid, thereby facilitating tube inser-
or positive verbiage. This style of question generally
tion.
elicits favorable responses from the patient.
(1:594–595), (16:589).
(1:296–297), (9:11–13), (15:426–427).
IIB2g
IIIB2a
130. A. The Lukens trap is situated in-line with the suction
127. A. The lingula is an anatomical part of the left-upper
tubing and is intended to be used as a specimen-
lobe and is sometimes thought of as the counterpart of
collection device. In the instance described here, the
the right-middle lobe. To drain the lingula, the CRT
CRT needs to check for the proper and appropriate

78 Chapter 2: Pretest
 connections for this apparatus. If both ends of the IIIE1g(1)
Luken’s trap are not appropriately connected to the 133. D. The decision to perform a tracheotomy or continue
suction system, adequate suction pressure will not be with ET intubation is not a clear one. Much contro-
generated. versy has centered on this dilemma. The duration of
(13:184), (16:603–604). intubation has increased in recent years. Certain refer-
ences adhere to a policy of “. . . if on the third day of
IIIF2 intubation there is a reasonable chance for the patient
not to need an artificial airway for an additional 72
131. A. According to the American Heart Association
hours, leave the endotracheal tube in place.” If it is de-
ACLS standards, a precordial thump is a Class IIb ac-
termined that the patient will definitely need an artifi-
tion. A Class IIb action is described as an acceptable
cial airway, then a tracheostomy should be performed.
action with the possibility of being helpful.
This “guideline” is largely based on the patient’s med-
So, in the situation presented in this question, admin- ical condition, however. The CRT should be cautious
istering a precordial thump is an acceptable action, be- in forming absolute statements relative to this clinical
cause the event was witnessed (ventricular fibrillation question. Studies attempting to answer this question
displayed on the ECG monitor), the victim was pulse- have shown that an absolute criterion cannot be estab-
less, and a defibrillator was unavailable. lished regarding when to perform a tracheotomy on an
intubated patient.
A precordial thump can convert a patient from ventric-
ular fibrillation into a coordinated cardiac activity. (1:601–602), (16:599–600).
Conversely, a precordial thump can convert a coordi-
nated cardiac activity into ventricular tachycardia or IIA1a(2)
ventricular fibrillation. 134. B. The general calculation used to determine the FIO2
(American Heart Association, Advanced Cardiac Life of tandemly arranged aerosol delivery systems is
Support, 1994, pp. 1–15, 1–17, and 4–8). shown here:
(FIO2)A(V̇)A + (FIO2)B(V̇)B + . . . (FIO2)n(V̇)n
ID1c FIO2 =
(V̇)A + (V̇)B + . . . (V̇)n
132. C. In this case, intervention should be directed toward
treating the pneumonia in a patient with the underlying Regarding the apparatus used in this problem,
diagnosis of cystic fibrosis. Antibiotics directed toward (FIO2)A = 0.40
the suspected infective bacteria are paramount. Be-
cause cystic fibrosis frequently has bronchospasm as a (V̇)A = 15 L/min.
component of the underlying disease, and because this (FIO2)B = 0.60
patient has clearly demonstrated wheezing, bron-
chodilator therapy is clearly indicated. Mobilization (V̇)B = 10 L/min.
and removal of secretions is clearly a problem for cys- Inserting the known values into the equation, the FIO2
tic fibrosis patients, and CPT is almost always in- delivered by this system is calculated as follows:
cluded as part of their daily program. Certainly, the
need for CPT is greater when there is an exacerbation (0.40)(15 L/min.) + (0.60)(10 L/min.)
FIO2 =
of the patient’s condition. 15 L/min. + 10 L/min.
The patient has hypoxemia as demonstrated by a PaO2 6 L/min. + 6 L/min.
of 42 mm Hg. Hence, oxygen therapy is in order and a =
25 L/min.
nasal cannula would suffice, but confirmation should
be sought by follow-up blood gases or pulse oximetry. = 0.48
Less-often ordered for cystic fibrosis patients than in
(1:752–753), (5:54).
the past, pediatric mist tents have no proven therapeu-
tic benefit. In fact, bland aerosols such as water carry
the hazards of causing bronchospasm and being a car-
IC1b
rier for infective organisms. Hydration of secretions is 135. D. Ipratropium bromide (Atrovent) is an anticholiner-
the desired benefit of bland aerosols, but nebulization gic bronchodilator, administered via an MDI, which
of water is an inefficient way to accomplish this thera- dispenses 0.02 mg per activation. About 30–90 min-
peutic objective. utes are necessary for maximal bronchodilatation to
occur. Therefore, waiting more than 30 minutes before
(15:721–725, 777–791, 794–795, 874–877), performing a postbronchodilator FVC after adminis-
(16:990–992). tering Atrovent would be appropriate. The time for

Chapter 2: Pretest 79
 maximum improvement in airflow to occur for beta- STEP 2: Obtain the patient’s inspiratory flow rate (V̇I)
two agonists is around 10–15 minutes. by multiplying the V̇E by the sum of the parts
of the I:E ratio (I:E ratio parts sum: 1 + 2 = 3).
(1:455, 577–578, 689), (15:181–183), (16:491, 1123).
V̇I = 5.4 L/min.  3
IIIE1h(4) = 16.2 L/min.
136. C. The instillation of normal saline into the airway at
the time of suctioning is normally unnecessary if the STEP 3: Insert the known values into the formula to
following conditions are met: (1) proper systemic hy- estimate the FIO2.
dration is maintained, (2) proper bronchial hygiene is
provided, and (3) proper humidification of inspired 3 L/min. + 0.21(16.2 L/min. – 3 L/min.)
FIO2 
gases is ensured. If these criteria are not maintained, 16.2 L/min.
however, the instillation of 3–5 ml of normal saline
3 L/min. + 0.21(13.2 L/min.)
before suctioning may help mobilize thick, retained, 
difficult-to-suction secretions. 16.2 L/min.

Instillation of saline should not be performed routinely 5.77 L/min.


and should be based on sound rationale and proper 16.2 L/min.
clinical judgment related to each individual patient.
 0.36
When assessing the response to normal saline instilla-
tion, you should decide whether to attempt the proce- (1:753), (5:54).
dure again.
(“Clinical Practice Guidelines: Endotracheal Suction- IB1b
ing of Mechanically Ventilated Adults and Children 138. A. Accessory muscles are used in patients with neuro-
with Artificial Airways,” 1993, Respiratory Care, muscular disease or spinal cord injury because of di-
38(5), pp. 500–504), (1:619). aphragmatic dysfunction. A COPD patient may also
have the diaphragm pushed down, reducing function. Pa-
IIA2a tients with pleurisy, however, breathe very shallowly in
response to pain that is associated with deep breathing.
137. A. A nasal cannula is classified as a low-flow oxygen-
delivery device. Low-flow oxygen-delivery systems (1:308, 310), (9:56–58, 61–62), (15:558–559),
cannot be relied on to deliver a constant or precise (16:164–168, 171).
FIO2, because these devices are influenced by changes
in the patient’s tidal volume, ventilatory rate, and over- IIID7
all breathing pattern. For example, the greater the pa- 139. A. In clinical practice, the mean airway pressure is
tient’s tidal volume, the lower the FIO2 will be because commonly used as a gauge of the potential cardiovas-
more room air dilutes the source gas (100% O2). The cular impact of positive pressure ventilation. The
converse of this statement is also true. harmful cardiovascular effects of positive pressure
The mathematical expression that follows can be used ventilation are basically a result of high positive pres-
to estimate the FIO2 rendered by a low-flow oxygen- sure within the lungs and the transmission of this pres-
delivery device. sure to the intrapleural space. Mean airway pressure
(Paw) is defined as the average pressure applied to the
V̇S + 0.21(VI – V̇S) lungs throughout one ventilatory cycle and represents
FIO2 
VI the total area under pressure-time curves from the on-
set of inspiration to the termination of exhalation. Ven-
where,
tilator settings that affect the Paw include the frequency,
V̇S = source gas flow (L/min.) the PIP, the inspiratory waveform, the duration of the
V̇I = patient’s inspiratory flow rate (L/min.) inspiratory time, the I:E ratio, and the PEEP level. Re-
garding expiratory times, the greater the duration of
STEP 1: Determine the patient’s minute ventilation
expiration, the more time will be available for in-
(V̇E).
trapleural pressure to return to normal. Thus, for a con-
V̇E = V̇T  f stant rate of breathing, longer expiratory times are
associated with a lesser cardiovascular effect.
= 450 ml  12 breaths/min.
Clinical research shows that higher levels of Paw are
= 5,400 ml/min. or 5.4 L/min.
associated with better arterial oxygenation, mainly

80 Chapter 2: Pretest
 because of alveolar recruitment. The likelihood of pul- The purpose of incorporating an oxygen blender in a
monary barotrauma, however, also correlates directly gas-delivery system is to deliver and maintain a pre-
with the magnitude of the Paw. cise FIO2 (Figure 2-23). A problem with delivering an
FIO2 in this manner is that it limits the flow to the
(1:888, 912–913), (10:143–144, 265–266, 285).
maximum that is accepted by a nebulizer (i.e., usually
around 12–15 L/min.). Such flow rates are inadequate
IIB1c for meeting the peak inspiratory flow demands of adult
140. B. The oxygen controller, or oxygen blender, (Figure patients. The use of this type of system is usually lim-
2-22) can be used with virtually any oxygen-delivery ited to younger pediatric patients.
system and apparatus. In this situation, with the oxy-
gen blender set at 40% O2, the jet nebulizer must be (1:758–759), (5:48–49), (13:81–84).
adjusted to 100% O2. Dialing the jet nebulizer to the
Blender Flowmeter
100% O2 setting prevents the entrainment of room
through the jet nebulizer so the source gas (40% O2) is
not diluted. If the air-entrainment port on the jet neb-
uilzer is open to any degree (i.e., any FIO2 setting less
than 1.0), the percentage of oxygen leaving the oxygen
blender will be reduced.

Air
O2

Figure 2-23: Air:oxygen blender used to provide precise

FIO2 through a jet nebulizer. Flow rate limitations can exist,
however.

Air-O2
Mixture
Control

Oxygen Alarm Air

Bypass
Outlet
Figure 2-22: Bird air:oxygen blender. From Bird Corpora-
tion, 3101 E. Alejo Road, Palm Springs, CA.

Chapter 2: Pretest 81
 REFERENCES
1. Scanlan, C., Spearman, C., and Sheldon, R., Egan’s 12. Koff, P., Eitzman, D., and New, J., Neonatal and Pedi-
Fundamentals of Respiratory Care, 7th ed., Mosby- atric Respiratory Care, 2nd ed., Mosby-Year Book,
Year Book, Inc., St. Louis, MO, 1999. Inc., St. Louis, MO, 1993.
2. Kacmarek, R., Mack, C., and Dimas, S., The Essentials 13. Branson, R., Hess, D., and Chatburn, R., Respiratory
of Respiratory Care, 3rd ed., Mosby-Year Book, Inc., Care Equipment, J. B. Lippincott, Co., Philadelphia,
St. Louis, MO, 1990. PA, 1995.
3. Shapiro, B., Peruzzi, W., and Kozlowska-Templin, R., 14. Darovic, G., Hemodynamic Monitoring: Invasive and
Clinical Applications of Blood Gases, 5th ed., Mosby- Noninvasive Clinical Application, 2nd ed., W. B. Saun-
Year Book, Inc., St. Louis, MO, 1994. ders Company, Philadelphia, PA, 1995.
4. Malley, W., Clinical Blood Gases: Application and Non- 15. Pierson, D., and Kacmarek, R., Foundations of Respira-
invasive Alternatives, W.B. Saunders Co., Philadel- tory Care, Churchill Livingston, Inc., New York, 1992.
phia, 1990. 16. Burton, et al., Respiratory Care: A Guide to Clinical
5. White, G., Equipment Theory for Respiratory Care, 3rd Practice, 4th ed., Lippincott-Raven Publishers,
ed., Delmar Publishers, Inc., Albany, NY, 1999. Philadelphia, PA, 1997.
6. Ruppel, G., Manual of Pulmonary Function Testing, 7th 17. Wojciechowski, W., Respiratory Care Sciences: An In-
ed., Mosby-Year Book, Inc., St. Louis, MO, 1998. tegrated Approach, 3rd ed., Delmar Publishers, Inc.,
7. Barnes, T., Core Textbook of Respiratory Care Practice, Albany, NY, 1999.
2nd ed., Mosby-Year Book, Inc., St. Louis, MO, 1994. 18. Aloan, C., Respiratory Care of the Newborn and Child,
8. Rau, J., Respiratory Care Pharmacology, 5th ed., 2nd ed., Lippincott-Raven Publishers, Philadelphia,
Mosby-Year Book, Inc., St. Louis, MO, 1998. PA, 1997.
9. Wilkins, R., Sheldon, R., and Krider, S., Clinical As- 19. Dantzker, D., MacIntyre, N., and Bakow, E., Compre-
sessment in Respiratory Care, 3rd ed., Mosby-Year hensive Respiratory Care, W. B. Saunders Company,
Book, Inc., St. Louis, MO, 1995. Philadelphia, PA, 1998.
10. Pilbeam, S., Mechanical Ventilation: Physiological and 20. Farzan, S., and Farzan, D., A Concise Handbook of Res-
Clinical Applications, 3rd ed., Mosby-Year Book, Inc., piratory Diseases, 4th ed., Appleton & Lange, Stam-
St. Louis, MO, 1998. ford, CT, 1997.
11. Madama, V., Pulmonary Function Testing and Car-
diopulmonary Stress Testing, 2nd ed., Delmar Publish-
ers, Inc., Albany, NY, 1998.

82 Chapter 2
 CHAPTER 3 CLINICAL DATA

PURPOSE: This chapter consists of 250 items intended to assess your understanding and comprehension of sub-
ject matter contained in the Clinical Data portion of the Entry-Level Examination for Certified Respiratory Thera-
pists. In this chapter, you will be required to answer questions regarding the following activities:

A. Reviewing existing data in a patient record and recommending diagnostic procedures based on all available
patient information
B. Collecting and evaluating additional pertinent clinical information
C. Performing procedures and interpreting results
D. Determining the appropriateness of the prescribed respiratory care plan, recommending modifications
where indicated, and participating in the development of the respiratory care plan
Remember from the introduction that the NBRC Entry-Level Examination is divided into three content areas:
I. Clinical Data
II. Equipment
III. Therapeutic Procedures
Table 3-1 indicates the number of questions on the NBRC Entry-Level Examination in the Clinical Data section and
the number of questions according to the level of complexity.
Table 3-1

Number of Questions Level of Complexity

Content Area in Content Area Recall Application Analysis

I. Clinical Data 25 7 14 4

This chapter is designed to help you work through the 68 NBRC matrix entries pertaining to clinical data on the
Entry-Level Examination. Keep in mind, however, that many of the 68 matrix entries in this content area encompass
multiple competencies. For example, Entry-Level Exam Matrix item IA1g(2) pertains to reviewing hemodynamic
data in the patient record. This matrix item encompasses (1) central venous pressure, (2) cardiac output, (3) pul-
monary capillary wedge pressure, (4) pulmonary artery pressures, (5) mixed venous oxygen, and (6) shunt studies.
Notice that matrix item IA1g(2) pertains to six different aspects of reviewing hemodynamic data. Therefore, at least
six different questions can come from this matrix item. Again, most other matrix items in this section and in the other
two sections entail multiple components.
Chapter Three is organized according to the order of the matrix items listed in the NBRC Entry-Level Examina-
tion Matrix. First, you will be presented with 95 questions that relate to matrix heading IA. Matrix heading IA ex-
pects you to:
IA—Review clinical data in the patient record and recommend diagnostic procedures
Second, you will be faced with 30 questions pertaining to matrix heading IB. Matrix heading IB reads as follows:
IB—In any clinical care setting, collect and evaluate clinical information.
Then, you will be confronted with 105 questions relating to matrix heading IC. Matrix heading IC requires you to:
IC—In any clinical care setting, perform procedures and interpret the results.

83
 Finally, you will be asked questions regarding matrix heading ID. Matrix heading ID asks you to:
ID—In any clinical care setting, determine the appropriateness of and participate in the development of
the respiratory care plan and recommend modifications.

Adhering to this sequence will assist you in organizing your personal study plan. Without a plan, your approach will
be haphazard and chaotic. Furthermore, you will waste precious time and effort studying unnecessary and irrelevant
material. Proceeding as outlined here, you will find your strengths and weaknesses in the Clinical Data content area.
After finishing each section (IA, IB, IC, and ID) within the content area of Clinical Data, stop to evaluate your
work by (1) studying the analyses (located further in this chapter), (2) reading references, and (3) reviewing the rel-
evant NBRC Entry-Level Exam matrix items. Following the questions pertaining to each of these matrix headings
(i.e., IA, IB, IC, and ID), you will find the pertinent portion of the Entry-Level Exam Matrix. Be sure to thoroughly
review these matrix items, because the NBRC develops the Entry-Level Exam from them.
In other words, evaluate your responses within section IA before advancing to section IB, and so on. Do not at-
tempt to answer all the questions in this chapter at one sitting. Doing so could be overwhelming. You should progress
through this chapter in the piecemeal fashion outlined previously.
Attempt to complete each section uninterruptedly. Allot yourself enough time (1) to answer the questions, (2) to
review the analyses, (3) to use the references as necessary, and (4) to thoroughly study the Entry-Level Examination
matrix items.
Although the sections in this chapter will be in sequence, i.e., IA, IB, IC, and ID, the questions within each section
will be randomized.
Table 3-2 indicates each content area within the Clinical Data section and the number of matrix items in each section.
Table 3-2

Clinical Number of Matrix

Data Sections Items Per Section

IA 19
IB 33
IC 8
ID 8
TOTAL 68

Use the answer sheet located on pages 85–89 to record your answers as you work through questions pertaining
to clinical data.
Remember, many matrix items have multiple components, and therefore certain matrix designations will be re-
peated but will pertain to different concepts. Make sure you read and study the matrix designations, because the
NBRC Entry-Level Examination is based on the Entry-Level Examination Matrix.

84 Chapter 3: Clinical Data

 Clinical Data Answer Sheet
DIRECTIONS: Darken the space under the selected answer.

A B C D A B C D
1. ❏ ❏ ❏ ❏ 25. ❏ ❏ ❏ ❏
2. ❏ ❏ ❏ ❏ 26. ❏ ❏ ❏ ❏
3. ❏ ❏ ❏ ❏ 27. ❏ ❏ ❏ ❏
4. ❏ ❏ ❏ ❏ 28. ❏ ❏ ❏ ❏
5. ❏ ❏ ❏ ❏ 29. ❏ ❏ ❏ ❏
6. ❏ ❏ ❏ ❏ 30. ❏ ❏ ❏ ❏
7. ❏ ❏ ❏ ❏ 31. ❏ ❏ ❏ ❏
8. ❏ ❏ ❏ ❏ 32. ❏ ❏ ❏ ❏
9. ❏ ❏ ❏ ❏ 33. ❏ ❏ ❏ ❏
10. ❏ ❏ ❏ ❏ 34. ❏ ❏ ❏ ❏
11. ❏ ❏ ❏ ❏ 35. ❏ ❏ ❏ ❏
12. ❏ ❏ ❏ ❏ 36. ❏ ❏ ❏ ❏
13. ❏ ❏ ❏ ❏ 37. ❏ ❏ ❏ ❏
14. ❏ ❏ ❏ ❏ 38. ❏ ❏ ❏ ❏
15. ❏ ❏ ❏ ❏ 39. ❏ ❏ ❏ ❏
16. ❏ ❏ ❏ ❏ 40. ❏ ❏ ❏ ❏
17. ❏ ❏ ❏ ❏ 41. ❏ ❏ ❏ ❏
18. ❏ ❏ ❏ ❏ 42. ❏ ❏ ❏ ❏
19. ❏ ❏ ❏ ❏ 43. ❏ ❏ ❏ ❏
20. ❏ ❏ ❏ ❏ 44. ❏ ❏ ❏ ❏
21. ❏ ❏ ❏ ❏ 45. ❏ ❏ ❏ ❏
22. ❏ ❏ ❏ ❏ 46. ❏ ❏ ❏ ❏
23. ❏ ❏ ❏ ❏ 47. ❏ ❏ ❏ ❏
24. ❏ ❏ ❏ ❏ 48. ❏ ❏ ❏ ❏

Chapter 3: Clinical Data 85

 A B C D A B C D
49. ❏ ❏ ❏ ❏ 77. ❏ ❏ ❏ ❏
50. ❏ ❏ ❏ ❏ 78. ❏ ❏ ❏ ❏
51. ❏ ❏ ❏ ❏ 79. ❏ ❏ ❏ ❏
52. ❏ ❏ ❏ ❏ 80. ❏ ❏ ❏ ❏
53. ❏ ❏ ❏ ❏ 81. ❏ ❏ ❏ ❏
54. ❏ ❏ ❏ ❏ 82. ❏ ❏ ❏ ❏
55. ❏ ❏ ❏ ❏ 83. ❏ ❏ ❏ ❏
56. ❏ ❏ ❏ ❏ 84. ❏ ❏ ❏ ❏
57. ❏ ❏ ❏ ❏ 85. ❏ ❏ ❏ ❏
58. ❏ ❏ ❏ ❏ 86. ❏ ❏ ❏ ❏
59. ❏ ❏ ❏ ❏ 87. ❏ ❏ ❏ ❏
60. ❏ ❏ ❏ ❏ 88. ❏ ❏ ❏ ❏
61. ❏ ❏ ❏ ❏ 89. ❏ ❏ ❏ ❏
62. ❏ ❏ ❏ ❏ 90. ❏ ❏ ❏ ❏
63. ❏ ❏ ❏ ❏ 91. ❏ ❏ ❏ ❏
64. ❏ ❏ ❏ ❏ 92. ❏ ❏ ❏ ❏
65. ❏ ❏ ❏ ❏ 93. ❏ ❏ ❏ ❏
66. ❏ ❏ ❏ ❏ 94. ❏ ❏ ❏ ❏
67. ❏ ❏ ❏ ❏ 95. ❏ ❏ ❏ ❏
68. ❏ ❏ ❏ ❏ 96. ❏ ❏ ❏ ❏
69. ❏ ❏ ❏ ❏ 97. ❏ ❏ ❏ ❏
70. ❏ ❏ ❏ ❏ 98. ❏ ❏ ❏ ❏
71. ❏ ❏ ❏ ❏ 99. ❏ ❏ ❏ ❏
72. ❏ ❏ ❏ ❏ 100. ❏ ❏ ❏ ❏
73. ❏ ❏ ❏ ❏ 101. ❏ ❏ ❏ ❏
74. ❏ ❏ ❏ ❏ 102. ❏ ❏ ❏ ❏
75. ❏ ❏ ❏ ❏ 103. ❏ ❏ ❏ ❏
76. ❏ ❏ ❏ ❏ 104. ❏ ❏ ❏ ❏

86 Chapter 3: Clinical Data

105. ❏ ❏ ❏ ❏ 134. ❏ ❏ ❏ ❏
106. ❏ ❏ ❏ ❏ 135. ❏ ❏ ❏ ❏
107. ❏ ❏ ❏ ❏ 136. ❏ ❏ ❏ ❏
108. ❏ ❏ ❏ ❏ 137. ❏ ❏ ❏ ❏
109. ❏ ❏ ❏ ❏ 138. ❏ ❏ ❏ ❏
110. ❏ ❏ ❏ ❏ 139. ❏ ❏ ❏ ❏
111. ❏ ❏ ❏ ❏ 140. ❏ ❏ ❏ ❏
112. ❏ ❏ ❏ ❏ 141. ❏ ❏ ❏ ❏
113. ❏ ❏ ❏ ❏ 142. ❏ ❏ ❏ ❏
114. ❏ ❏ ❏ ❏ 143. ❏ ❏ ❏ ❏
115. ❏ ❏ ❏ ❏ 144. ❏ ❏ ❏ ❏
116. ❏ ❏ ❏ ❏ 145. ❏ ❏ ❏ ❏
117. ❏ ❏ ❏ ❏ 146. ❏ ❏ ❏ ❏
118. ❏ ❏ ❏ ❏ 147. ❏ ❏ ❏ ❏
119. ❏ ❏ ❏ ❏ 148. ❏ ❏ ❏ ❏
120. ❏ ❏ ❏ ❏ 149. ❏ ❏ ❏ ❏
121. ❏ ❏ ❏ ❏ 150. ❏ ❏ ❏ ❏
122. ❏ ❏ ❏ ❏ 151. ❏ ❏ ❏ ❏
123. ❏ ❏ ❏ ❏ 152. ❏ ❏ ❏ ❏
124. ❏ ❏ ❏ ❏ 153. ❏ ❏ ❏ ❏
125. ❏ ❏ ❏ ❏ 154. ❏ ❏ ❏ ❏
126. ❏ ❏ ❏ ❏ 155. ❏ ❏ ❏ ❏
127. ❏ ❏ ❏ ❏ 156. ❏ ❏ ❏ ❏
128. ❏ ❏ ❏ ❏ 157. ❏ ❏ ❏ ❏
129. ❏ ❏ ❏ ❏ 158. ❏ ❏ ❏ ❏
130. ❏ ❏ ❏ ❏ 159. ❏ ❏ ❏ ❏
131. ❏ ❏ ❏ ❏ 160. ❏ ❏ ❏ ❏
132. ❏ ❏ ❏ ❏ 161. ❏ ❏ ❏ ❏
133. ❏ ❏ ❏ ❏ 162. ❏ ❏ ❏ ❏

Chapter 3: Clinical Data 87

 A B C D A B C D
163. ❏ ❏ ❏ ❏ 191. ❏ ❏ ❏ ❏
164. ❏ ❏ ❏ ❏ 192. ❏ ❏ ❏ ❏
165. ❏ ❏ ❏ ❏ 193. ❏ ❏ ❏ ❏
166. ❏ ❏ ❏ ❏ 194. ❏ ❏ ❏ ❏
167. ❏ ❏ ❏ ❏ 195. ❏ ❏ ❏ ❏
168. ❏ ❏ ❏ ❏ 196. ❏ ❏ ❏ ❏
169. ❏ ❏ ❏ ❏ 197. ❏ ❏ ❏ ❏
170. ❏ ❏ ❏ ❏ 198. ❏ ❏ ❏ ❏
171. ❏ ❏ ❏ ❏ 199. ❏ ❏ ❏ ❏
172. ❏ ❏ ❏ ❏ 200. ❏ ❏ ❏ ❏
173. ❏ ❏ ❏ ❏ 201. ❏ ❏ ❏ ❏
174. ❏ ❏ ❏ ❏ 202. ❏ ❏ ❏ ❏
175. ❏ ❏ ❏ ❏ 203. ❏ ❏ ❏ ❏
176. ❏ ❏ ❏ ❏ 204. ❏ ❏ ❏ ❏
177. ❏ ❏ ❏ ❏ 205. ❏ ❏ ❏ ❏
178. ❏ ❏ ❏ ❏ 206. ❏ ❏ ❏ ❏
179. ❏ ❏ ❏ ❏ 207. ❏ ❏ ❏ ❏
180. ❏ ❏ ❏ ❏ 208. ❏ ❏ ❏ ❏
181. ❏ ❏ ❏ ❏ 209. ❏ ❏ ❏ ❏
182. ❏ ❏ ❏ ❏ 210. ❏ ❏ ❏ ❏
183. ❏ ❏ ❏ ❏ 211. ❏ ❏ ❏ ❏
184. ❏ ❏ ❏ ❏ 212. ❏ ❏ ❏ ❏
185. ❏ ❏ ❏ ❏ 213. ❏ ❏ ❏ ❏
186. ❏ ❏ ❏ ❏ 214. ❏ ❏ ❏ ❏
187. ❏ ❏ ❏ ❏ 215. ❏ ❏ ❏ ❏
188. ❏ ❏ ❏ ❏ 216. ❏ ❏ ❏ ❏
189. ❏ ❏ ❏ ❏ 217. ❏ ❏ ❏ ❏
190. ❏ ❏ ❏ ❏ 218. ❏ ❏ ❏ ❏

88 Chapter 3: Clinical Data

219. ❏ ❏ ❏ ❏ 235. ❏ ❏ ❏ ❏
220. ❏ ❏ ❏ ❏ 236. ❏ ❏ ❏ ❏
221. ❏ ❏ ❏ ❏ 237. ❏ ❏ ❏ ❏
222. ❏ ❏ ❏ ❏ 238. ❏ ❏ ❏ ❏
223. ❏ ❏ ❏ ❏ 239. ❏ ❏ ❏ ❏
224. ❏ ❏ ❏ ❏ 240. ❏ ❏ ❏ ❏
225. ❏ ❏ ❏ ❏ 241. ❏ ❏ ❏ ❏
226. ❏ ❏ ❏ ❏ 242. ❏ ❏ ❏ ❏
227. ❏ ❏ ❏ ❏ 243. ❏ ❏ ❏ ❏
228. ❏ ❏ ❏ ❏ 244. ❏ ❏ ❏ ❏
229. ❏ ❏ ❏ ❏ 245. ❏ ❏ ❏ ❏
230. ❏ ❏ ❏ ❏ 246. ❏ ❏ ❏ ❏
231. ❏ ❏ ❏ ❏ 247. ❏ ❏ ❏ ❏
232. ❏ ❏ ❏ ❏ 248. ❏ ❏ ❏ ❏
233. ❏ ❏ ❏ ❏ 249. ❏ ❏ ❏ ❏
234. ❏ ❏ ❏ ❏ 250. ❏ ❏ ❏ ❏

Chapter 3: Clinical Data 89

 Clinical Data Assessment
IA—Review data in the patient record and recommend diagnostic procedures.
NOTE: You should stop to evaluate your performance on the 95 questions pertaining to the matrix section IA. Please refer
to the NBRC Entry-Level Examination Matrix designations located at the end of the IA content area of the Clini-
cal Data section to assist you in evaluating your performance on the test items in this section.
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the one that is best in each case, and then blacken the corresponding space on
the answer sheet found in the front of this chapter. Good luck.

IA2c IA1c
1. A patient is suspected of having an obstruction of the 5. The CRT notices that the latest blood-chemistry report
upper airway. Which of the following tests would be in the patient’s chart indicates a hemoglobin concen-
helpful in providing information about this condition? tration of 20 g%. What is the significance of this data?
A. flow-volume loop A. The patient is polycythemic.
B. single-breath N2 elimination B. The patient is hypovolemic.
C. diffusing capacity C. The patient has a pulmonary infection.
D. bronchial provocation D. The patient displays decreased capillary refill.

IA1g(2) IA2f
2. A patient with a body temperature of 39ºC is breathing 6. Which of the following cardiac features are generally
room air and has a normal cardiac output. What would discernable from an echocardiogram?
be the expected Sv̄O2 value?
I. hypokinesis of ischemic myocardium
A. greater than 70% II. left ventricular hypertrophy
B. 75% III. regurgitant aortic valve
C. 85% IV. atherosclerotic plaque in coronary vessels
D. greater than 85%
A. I, IV only
B. I, II, III only
IA2a C. II, III, IV only
3. A four-year old child who has a brassy, barking cough D. I, II, III, IV
and a muffled voice is brought to the emergency room.
The child is sitting up, leaning forward, and drooling. IA1f(2)
What should the CRT recommend for this patient?
7. Which two points on the pressure-time waveform
A. direct laryngoscopy shown in Figure 3-1 provide for the calculation of the
B. lateral neck radiograph pressure generated to overcome airway resistance to
C. bronchodilator therapy gas flow during inspiration?
D. pharyngeal suctioning

IA1h
Airway Pressure

4. The CRT is reviewing the results of an amniocentesis

B
performed on a 24-year-old woman. The data indicate an
L/S ratio of 3:1. What does the value of this ratio mean? D
C
A. that there is a high probability that the fetus is
likely to experience respiratory distress at birth
B. that the unborn child has mature lungs E
C. that the unborn child has pulmonary prematurity A
Time
D. that the unborn child will likely have a low birth
weight Figure 3-1: Pressure-time waveform.

90 Chapter 3: Clinical Data

 A. DE IA1f(5)
B. CD 12. Which of the following factors affect the end-tidal CO2
C. BC measurements via capnography?
D. AB
I. cardiac output
IA1g(2) II. ventilation-perfusion ratio
III. fraction of inspired oxygen
8. While reviewing the chart of a patient who has severe IV. alveolar ventilation
COPD, the CRT notices that the patient has cor
pulmonale. Which of the following hemodynamic A. II, III only
changes would be expected? B. I, II, III only
C. I, II, IV only
A. decreased pulmonary capillary wedge pressure D. I, II, III, IV
B. decreased central venous pressure
C. increased cardiac output
IA1a
D. increased pulmonary artery diastolic pressure
13. Which of the following sections of the patient’s chart
IA2a would contain a physician’s assessment of the effec-
tiveness of a respiratory care procedure being admin-
9. A patient receiving mechanical ventilation is sus- istered?
pected of having pneumothorax. What procedure
should the CRT recommend to confirm the diagnosis? A. admission physical exam
B. respiratory care flow sheet
A. arterial blood gas C. patient progress notes
B. chest radiograph D. patient history
C. bronchoscopy
D. peak flow measurement
IA1b
IA1h 14. Which of the following measurements are considered
vital signs?
10. A newborn has a one-minute Apgar score of five. What
type of intervention would be appropriate based on I. sensorium
this score? II. body temperature
III. ventilatory rate
A. temperature maintenance, drying, and airway clear- IV. blood pressure
ance
B. endotracheal intubation and mechanical ventilation A. II, IV only
C. increased FIO2s via bag-mask ventilation B. I, II, III only
D. cardiopulmonary resuscitation C. I, II, IV only
D. II, III, IV only
IA1d
11. A 44-year-old male in a diabetic coma enters the emer- IA2c
gency department. An arterial blood sample while the 15. Which of the following diagnostic procedures pro-
patient breathed room air was obtained immediately. vides data for assessing the degree of reversible airway
Analysis of the sample revealed the following: disease?
PaO2 110 torr A. methacholine challenge
PaCO2 10 torr B. lung scan
pH 7.10 C. before and after bronchodilator study
HCO3̄ 3 mEq/L D. volume of isoflow
B.E. –21 mEq/L
IA1f(2)
Which of the following blood-gas interpretations is
correct? 16. Calculate a patient’s minute ventilation based on the
data given below.
A. partially compensated metabolic acidosis
B. mixed respiratory and metabolic acidosis FRC 2,400 cc
C. compensated respiratory alkalosis RV 1,400 cc
D. fully compensated metabolic acidosis VT 700 cc
f 12 breaths/min.

Chapter 3: Clinical Data 91

 A. 8,400 cc/min. Based on these data, what should the CRT infer?
B. 4,500 cc/min.
A. The patient had no ECG abnormalities.
C. 3,800 cc/min.
B. The patient experienced sinus bradycardia.
D. 3,600 cc/min.
C. The patient had an acute myocardial infarction.
D. The patient experienced premature ventricular con-
IA2c
tractions.
17. A physician wishes to determine whether a patient’s
pulmonary disease has a reversible component. What
procedure could the CRT recommend to ascertain this IA2d
phenomenon? 21. A patient who has congestive heart failure is being
seen by a physician. The physician asks the CRT to
A. lung scan
recommend the most appropriate method of hemody-
B. nitrogen washout
namic monitoring. Which of the following procedures
C. single breath CO2 elimination
should the CRT recommend?
D. spirometry before and after bronchodilator
A. pulmonary artery catheter
IA2f B. central venous catheter
18. A 53-year-old male enters the emergency department C. arterial cannulation
expressing the following complaints: D. transcutaneous monitoring

• orthopnea
• paroxysmal noctural dyspnea IA1c
• syncope 22. While reviewing the chart of an ICU patient, the CRT
• diaphoresis notices that the patient’s urine output has been pro-
• night sweats gressively falling and is now 10 ml/hr. Which of the
following terms describes this condition?
What should the CRT recommend at this time?
A. uremia
A. an electrocardiogram
B. anuria
B. an arterial puncture procedure
C. polyuria
C. pulmonary artery catheterization
D. oliguria
D. pulmonary function testing

IA1f(5) IA1a
19. Which of the following situations are indications for 23. The physician’s order for a respiratory care modality
capnography? should specify all of the following components EX-
CEPT
I. to evaluate mean exhaled CO2 levels
II. to assess the placement of an endotracheal tube A. medication dosage.
III. to determine the efficacy of mechanical ventilation B. duration of treatment.
IV. to assess the degree of intrapulmonary shunting C. possible side effects.
D. oxygen concentration.
A. II, III only
B. I, IV only
C. I, II, III only IA2a
D. I, II, III, IV 24. The CRT is attempting to determine on a COPD
patient the range of movement of the diaphragm via
IA1g(1) percussion. She is having difficulty distinguishing
20. While reading a patient’s chart, the CRT is reviewing among the percussion notes to ascertain the di-
an ECG tracing obtained earlier in the day. The ECG aphragm’s position. Which of the following pro-
data are listed. cedures should she recommend to determine dia-
phragmatic movement?
HEART RATE: 68 bpm
P-R INTERVAL: 0.17 second A. radiography
QRS INTERVAL: 0.11 second B. bronchoscopy
S-T SEGMENT: isoelectric C. lung scan
T WAVE: upright and round D. pneumotachography

92 Chapter 3: Clinical Data

IA1f(1) I. left atrial pressure
25. How long should the maximum inspiratory pressure II. pulmonary artery pressure
measurement be made to ensure that an ICU patient III. left ventricular end-diastolic pressure
achieves a maximum diaphragmatic contraction? IV. pulmonary venous pressure

A. 5 seconds A. II, III, IV only

B. 10 seconds B. I, II, III only
C. 20 seconds C. I, III, IV only
D. 40 seconds D. I, II, III, IV

IA1f(2) IA1f(4)
26. While reviewing the chart of a patient who is receiving 29. While reviewing a patient’s chart, the CRT observes
mechanical ventilation, the CRT observes the volume- that the patient’s VD/VT is 0.65. Which condition(s)
pressure curves reflecting the static and dynamic com- might be responsible for this value?
pliance values. The static compliance curve is in a
normal position (refer to Figure 3-2). I. pneumonia
II. pulmonary embolism
III. diffuse atelectasis
Static
IV. positive pressure mechanical ventilation
Compliance A. II only
Curve
Volume

B. I, III only
C. II, IV only
Dynamic
Compliance D. I, II, III only
Curve

IA2d
30. A physician wants to establish a route by which he can
Pressure administer medications, maintain circulatory volume,
Figure 3-2: Static and dynamic compliance curves. and obtain mixed venous blood samples. Which of the
following vascular access routes would be most ap-
Which of the following conditions would likely be responsi- propriate?
ble for the position of the dynamic compliance curve?
A. arterial cannulation
I. mucous plugging B. intravenous line
II. atelectasis C. central venous line
III. right mainstem bronchus intubation D. dorsalis pedis catheterization
IV. pneumothorax
A. I only
IA2c
B. IV only
C. II, III only 31. What respiratory data relating to lung mechanics
D. I, II, IV only would be useful to obtain from a neuromuscular dis-
ease patient?
IA1c I. body plethysmography
27. Upon reviewing a patient’s chart, the CRT notes that II. maximum inspiratory pressure
the patient has neutrophilia with increased bands and III. maximum expiratory pressure
an increased total white blood cell count. What condi- IV. volume of isoflow
tion is likely occurring with this patient? A. II, III only
A. pneumonia B. I, IV only
B. COPD C. I, II, IV only
C. congestive heart failure D. I, II, III only
D. pulmonary fibrosis
IA1f(2)
IA1g(2)
32. Which of the following volume-time waveforms (Fig-
28. Under normal conditions, which of the following he- ures 3-3a–d) illustrated as follows depicts intermittent
modynamic measurements are represented by the pul- mandatory ventilation?
monary capillary wedge pressure reading?

Chapter 3: Clinical Data 93

 A.
1000
Volume (cc)

800
600
400
200
0
2 4 6 8 10 12 14 16 18 20 Time (seconds)
Figure 3-3a

B.
800
Volume (cc)

600
400
200
0
2 4 6 8 10 12 14 Time (seconds)
Figure 3-3b

C.

300
Volume (cc)

200

100

0
2 4 6 8 10 12 14 16 18 Time (seconds)
Figure 3-3c

D.

800
Volume (cc)

600
400
200
0
2 4 6 8 10 12 14 Time (seconds)
Figure 3-3c

IA2e emphysema (PIE). What type of monitoring would be

33. When evaluating airway resistance data obtained from a critical to assure rapid selection and adjustment of
body plethysmograph, what range is accepted as normal? ventilation settings?

A. 0.5 to 1.5 cm H2O/L/sec A. transcutaneous PO2 and PCO2

B. 1.0 to 1.75 cm H2O/L/sec B. pulse oximetry
C. 0.6 to 2.4 cm H2O/L/sec C. pulmonary arterial pressure
D. 1.5 to 3.0 cm H2O/L/sec D. central venous pressure

IA2f IA1f(1)
34. High-frequency jet ventilation (HFJV) is to be initi- 35. Which of the following measurements obtained from
ated on an infant who has severe pulmonary interstitial an intubated and mechanically ventilated 55-kg patient

94 Chapter 3: Clinical Data

 indicate that this patient is a candidate for weaning A. III, IV only
from mechanical ventilation? B. I, II, IV only
C. I, II, III only
I. vital capacity: 820 ml
D. I, II, III, IV
II. resting minute ventilation: 12 liters/minute
III. maximum inspiratory pressure: –42 cm H2O
IV. patient-ventilation system compliance of 45 ml/ IA2d
cmH2O 40. A neonate is receiving supplemental oxygen via an
A. I, II only oxyhood and is having its oxygenation status moni-
B. I, III only tored with a pulse oximeter. The pulse oximeter indi-
C. II, III, IV only cates an SpO2 of 100%. What action should the CRT
D. I, II, III, IV take at this time?
A. Continue present therapy and current monitoring.
IA1f(5) B. Obtain an arterial blood sample.
36. In which patient scenario would a pulse oximeter ren- C. Lower the FIO2 delivered by the oxyhood.
der a falsely high SpO2 reading? D. Discontinue the oxyhood and administer oxygen
through an isolette.
A. a patient who had been breathing carbon monoxide
B. a patient breathing oxygen
C. a patient whose peripheral pulses cannot be detected IA2c
D. a patient shivering 41. Which of the following pulmonary function tests can
be used to evaluate the mechanical properties of the
IA1g(1) lungs and chest wall, particularly when airflow resis-
37. The position at which the systolic thrust is palpable is tance is increased?
called the
A. diffusing capacity
A. point of maximal impulse. B. volume of isoflow
B. systolic gallop. C. maximum voluntary ventilation
C. substernal heave. D. forced vital capacity maneuver
D. systolic thrill.
IA1b
IA2a
42. Which of the following laboratory results would be
38. Which of the following chest radiograph findings are
considered abnormal as they pertain to the medical
associated with obstructive lung disease?
history of a 35-year-old female patient?
I. increased opacity of all lung fields
I. an arterial oxygen tension of 78 mm Hg on
II. horizontal rib angles
room air
III. right hemidiaphragm elevated 2 cm higher than
II. an arterial pH of 7.42
the left hemidiaphragm
III. an oxyhemoglobin saturation of 88%
IV. increased anteroposterior diameter
IV. an arterial carbon dioxide tension of 44 mm Hg
A. I, II, IV only
A. I, III only
B. I, III, IV only
B. II, IV, V only
C. II, IV only
C. I, III, IV only
D. III, IV only
D. I, III, V only
IA1c
39. An adult patient who is suspected of having a commu- IA1g(2)
nity-acquired pneumonia is about to be admitted to a 43. A patient who has a central venous pressure (CVP)
hospital. Which of the following tests should be per- measurement of 15 torr would most likely have a fa-
formed on this patient? vorable response to which medication?
I. gram stain of sputum sample A. antidysrhythmic agent
II. blood chemistries B. negative inotrope
III. cardiac enzymes C. diuretic
IV. arterial blood gas analysis D. negative chronotrope

Chapter 3: Clinical Data 95

IA2d III. pH
44. An infant who is receiving mechanical ventilation dis- IV. protein
plays a trend of increasing transcutaneous carbon A. I, II, III, IV
dioxide tensions (PtcO2). Remembraning and calibrat- B. I, III, IV only
ing the transcutaneous monitor does not result in a C. II, III only
change, nor does suctioning the infant’s endotracheal D. I, IV only
tube. What information should be obtained next?
A. chest X-ray IA1b
B. arterial blood gases 49. Which procedures should be performed during a phys-
C. bronchoscopy ical examination of the chest?
D. echocardiography
I. percussion
IA1d II. vibration
III. auscultation
45. A patient arrives at the emergency department with a IV. palpation
presumed exacerbation of COPD. He is receiving oxy-
gen by nasal cannula at 2 liters/minute and appears to A. I, III, IV only
be in moderate respiratory distress. What action B. III, IV only
should the CRT recommend? C. I, II only
D. II, IV only
A. Obtain an arterial blood gas.
B. Change to a non-rebreathing mask at 8 liters/
IA1a
minute.
C. Institute pulse oximetry. 50. Which of the following actions should the CRT per-
D. Intubate and mechanically ventilate. form first before instituting oxygen therapy on a newly
admitted patient?
IA1f(2) A. Determine the SpO2.
46. What is the normal I:E ratio for a spontaneously B. Verify the physician’s order.
breathing adult? C. Perform an arterial blood gas puncture.
D. Auscultate the patient’s thorax.
A. 1:3
B. 1:2
C. 2:1 IA1g(2)
D. 3:1 51. While reviewing the chart of a post-myocardial infarc-
tion patient, the CRT notices that the patient’s my-
IA1h ocardium has experienced a decreased compliance.
47. A preterm, 900-gram neonate has a transcutaneous What would be the result in this situation if the PCWP
oxygen electrode placed on the right upper chest and was used to estimate the patient’s left ventricular end-
has an umbilical artery catheter (UAC) in place. The diastolic volume (LVEDV)?
transcutaneous PO2 is 55 mm Hg, while a blood gas A. The PCWP would correlate well with the
drawn from the UAC reveals a PO2 of 40 mm Hg. LEVDV.
What is the likely cause of the difference between B. The PCWP would overestimate the LEVDV.
these two measurements? C. The PCWP would underestimate the LVEDV.
A. An air bubble might have gotten under the tran- D. The PCWP would render fluctuating values for
scutaneous sensor. the LVEDV.
B. The temperature of the transcutaneous electrode
is too low. IA2c
C. A right-to-left shunt might be present. 52. A patient who complains of frequent tightening of the
D. The PO2 electrode on the blood-gas analyzer was chest and frequent coughing cannot perform a maxi-
recently replaced. mum forced expiratory maneuver. Which of the fol-
lowing tests should the CRT recommend to obtain
IA1c appropriate data about this patient?
48. Which of the following urine characteristics generally
A. seven-minute N2 washout
appear in a routine urinalysis?
B. body plethysmography
I. specific gravity C. diffusing capacity
II. ketones D. maximum voluntary ventilation

96 Chapter 3: Clinical Data

IA1f(4) IA1g(2)
53. Which of the following measurements must be made 57. During the calculation of the CċO2 while performing a
to provide for the calculation of the VD/VT ratio? shunt study on a patient, the partial pressure of oxygen
in the pulmonary capillary blood (PċO2) is assumed to
I. Pv̄ CO2
be equal to the
II. PĒ CO2
III. PETCO2 A. Pv̄O2
IV. PaCO2 B. PAO2
C. PaO2
A. II, IV only
D. Sv̄O2
B. I, II only
C. II, III only
D. III, IV only IA2c
58. A physician wants to measure a patient’s FRC. She
asks the CRT to recommend a diagnostic procedure
IA1d
that will yield the most accurate data, despite patient
54. The following arterial blood gas data were obtained air-trapping. Which of the following tests should the
from a patient having a normal respiratory quotient CRT recommend?
and breathing an FIO2 of 0.28 at sea level.
A. body plethysmography
PaO2 225 mm Hg B. volume of isoflow
PaCO2 44 mm Hg C. closed-circuit helium dilution
pH 7.35 D. open-circuit nitrogen washout
HCO 3̄ 24 mEq/L
B.E. 0 mEq/L IA1f(2)
59. What is the amount of maximum inspiratory pressure
Which of the following statements describe the PaO2
that is generally sufficient to produce a vital capacity
value?
approximately equivalent to 15 ml/kg?
A. Air bubbles contaminated the sample.
A. –5 cm H2O
B. The patient hyperventilated.
B. –10 cm H2O
C. The patient’s hypoxemia was overcorrected.
C. –15 cm H2O
D. An analytical error has occurred.
D. –20 cm H2O

IA1b IA1f(4)
55. Which of the following vital sign measurements are 60. Approximately how much anatomic dead space does a
abnormal for a middle-aged adult patient at rest? 75-kg (IBW) person have?
I. body temperature of 36ºC A. 165 cc
II. heart rate of 100 beats/minute B. 150 cc
III. blood pressure of 130/100 mm Hg C. 130 cc
IV. ventilatory rate of 8 breaths/minute D. 75 cc
A. I only
B. II, III, IV only IA1f(3)
C. I, III, IV only 61. Which of the following measurements reflect volume
D. I, II, III, IV change per unit of pressure change?
A. compliance
IA1f(1) B. conductance
56. How many anthropometric factors need to be known C. resistance
about a patient to determine the predicted normal D. impedance
FEV1?
A. two IA2c
B. three 62. A patient who has an undiagnosed, recurring cough
C. four and receives ipratropium bromide, 2 puffs QID via an
D. five MDI, has been scheduled for a bronchoprovocation

Chapter 3: Clinical Data 97

 test. What is the recommended time for withholding IA1g(2)
this medication before the bronchoprovocation test? 66. Which of the following CVP values would be consis-
A. 24 hours before the bronchoprovocation tent with that of a patient receiving positive pressure
B. 18 hours before the bronchoprovocation mechanical ventilation with PEEP?
C. 12 hours before the bronchoprovocation A. 16 mm Hg
D. 8 hours before the bronchoprovocation B. 8 mm Hg
C. 6 mm Hg
IA1f(5) D. 4 mm Hg
63. Which of the following forms of oxygen monitoring
would be most appropriate to use during a bron- IA2c
choscopy procedure? 67. Which of the following tests would possibly be ad-
A. pulse oximetry versely influenced if the subject smoked a cigarette an
B. blood gas analysis hour or less before performing the test?
C. transcutaneous monitoring A. single-breath nitrogen elimination
D. co-oximetry B. maximum voluntary ventilation
C. body plethysmography
IA2e D. diffusing capacity
64. When would it be appropriate for the CRT to measure IA1f(2)
the peak expiratory flow rate in a pre-operative assess-
ment? 68. The CRT is reviewing mechanical ventilation data of a
patient and notes the flow-time curve shown in Figure
A. when the patient has had a chest X-ray within the 3-4. Which of the following modes of ventilation is the
last hour patient receiving?
B. when the patient used an inhaled bronchodilator
within the last hour A. SIMV with pressure-support ventilation
C. when the patient had smoked a cigarette within B. inverse-ratio ventilation
the last hour C. pressure-support ventilation
D. when the patient had ingested a large meal within D. pressure-control ventilation
the last hour
IA1f(4)
IA2d 69. Given the data below, calculate the patient’s dead
space fraction.
65. The CRT expects a patient to require numerous arter-
ial blood samples obtained per day. Which of the fol- PaO2 75 torr
lowing recommendations should the CRT make to the PaCO2 49 torr
physician to minimize patient discomfort during the pH 7.38
procedures? FIO2 0.40
PĒ CO2 32 torr
A. a pulmonary artery catheter
B. transcutaneous oxygen monitoring A. 0.21
C. a central venous pressure line B. 0.35
D. an arterial line C. 0.47
D. 0.68

Flow (lpm)
80
60
40
20
0
-20 2 4 6 8 10 12 14
-40
-60
-80
Figure 3-4: Flow-time waveform.

98 Chapter 3: Clinical Data

IA1b IA1a
70. Which of the following terms describes dyspnea that 75. The attending physician’s observations of the patient’s
occurs while a patient sits or stands? ongoing hospital course can be located in which sec-
tion of the patient chart?
A. orthopnea
B. platypnea A. history and physical exam
C. eupnea B. physician orders
D. bradypnea C. progress notes
D. graphic charts

IA1g(2) IA1f(5)
71. While evaluating the chart of a normal subject who has 76. How does the PETCO2 correlate with the PaCO2 in a
just completed an exercise test, the CRT notes that the healthy adult subject?
subject had a V̇O2 of 250 ml/min. and a cardiac output
A. The PETCO2 exceeds the PaCO2.
of 5 liters/min. What assessment of the C(a-v̄)O2
B. The PETCO2 is less than the PaCO2.
would be appropriate?
C. The PETCO2 approximately equals the PaCO2.
A. normal D. The PETCO2 varies inversely with the PaCO2.
B. increased
C. decreased IA1g(1)
D. cannot be assessed 77. While reviewing a patient’s chart, the CRT notices that
the patient’s latest blood pressure was 150/100 mm
IA1c Hg. How should the CRT classify this recording?
72. The CRT notices that the latest lab data in the patient’s A. normal
chart reveals a white blood cell count of 9,000/mm3. B. hypotension
How should the CRT interpret this data? C. hypertension
D. tachycardia
A. The patient has pneumonia.
B. The patient has an empyema. IA2a
C. A sputum culture and sensitivity test should be
performed. 78. A patient is suspected of having a pulmonary em-
D. The white blood cell count is normal. bolism. Which of the following diagnostic tests is ap-
propriate to use to assist in the diagnosis?
A. ventilation-perfusion lung scan
IA2c
B. CT scan
73. Which of the following pulmonary function tests C. MRI
should be recommended to evaluate the distribution of D. chest radiography
ventilation in a COPD patient?
A. diffusing capacity IA1h
B. body plethysmography 79. When should Apgar scores be assessed on newborns?
C. maximum voluntary ventilation
A. 1 minute and 5 minutes after birth
D. single-breath nitrogen elimination
B. 1 minute and 3 minutes after birth
C. 2 minutes and 5 minutes after birth
IA2f D. 3 minutes and 6 minutes after birth
74. A patient is about to perform an exercise test. The
physician asks the CRT to recommend a means for IA1a
continuously monitoring the patient’s oxygenation sta- 80. When obtaining the history of the present illness from
tus during the exercise test. Which of the following a patient, what type of statement or question should the
methods should the CRT recommend? CRT avoid stating?
A. pulse oximetry A. “Tell me about your difficulty breathing.”
B. arterial blood gas sampling from an arterial line B. “Your chest pain occurs only when you walk up
C. mixed venous blood gas sampling for a pulmonary stairs, right?”
artery catheter C. “What makes your pain feel worse?”
D. co-oximetry D. “When did your coughing problem first begin?”

Chapter 3: Clinical Data 99

IA1e IA1h
81. When is the most appropriate time to review a patient’s 86. What does the designation G3, P2, Ab0 represent in
chest X-ray? the maternal history?
A. any time before admission A. three low Apgar scores, two pregnancies, and no
B. before obtaining the history of present illness Cesarean sections
C. before performing the physical examination B. three pregnancies, two live births, and no abortions
D. after obtaining the history of present illness and C. three live births, two currently alive children, and
after performing the physical examination no abortions
D. three pregnancies, two premature births, and no
IA1b abdominal deliveries
82. An anterior protrusion of the sternum is called
IA2d
A. barrel chest.
B. pectus excavatum. 87. If a patient has chronic CO2 retention, she would be ex-
C. kyphosis. pected to have a(n) ____________________ PCO2 in
D. pectus carinatum. the _____________ in comparison with a person who
has a normal arterial blood gas and acid-base status.
IA1g(1) I. increased; cerebrospinal fluid
83. When the CRT assesses a patient’s pulse rate, what II. increased; arterial blood
features of the pulse rate need to be evaluated? III. decreased; cerebrospinal fluid
IV. decreased; arterial blood
I. rhythm
II. pressure A. I, II only
III. strength B. IV only
IV. rate C. III, IV only
D. I, IV only
A. III, IV only
B. I, II, IV only
IA2a
C. I, III, IV only
D. I, II, III, IV 88. A patient’s chest roentgenogram reveals a number of
hilar lung masses. A positive sputum cytology has
IA2a been obtained. Which of the following diagnostic pro-
cedures should the CRT recommend for obtaining ad-
84. A patient has been found to have a peripheral carcinoma ditional clinical data?
of the lung. What diagnostic procedure would be most
useful to help place a biopsy needle into the lesion? A. flexible bronchoscopy
B. ventilation-perfusion scan
A. chest radiography C. sputum sample
B. lung scan D. complete blood count
C. CT scan
D. pulmonary angiography
IA1f(2)
IA1f(2) 89. If a patient has a minute ventilation of 9.6 liters/minute
and a ventilatory frequency of 10 breaths/minute, what
85. The following respiratory data were obtained at the
is the patient’s tidal volume?
bedside from a 150-lb (IBW) patient.
A. 960.0 ml
• maximum inspiratory pressure (MIP): –60 cm
B. 96.0 ml
H2O
C. 9.6 l
• maximum expiratory pressure (MEP): 100 cm
D. 96.0 l
H2O
• ventilatory rate (f): 12 breaths/minute
• minute ventilation (V̇E ): 6.00 liters/minute IA2b
90. A sputum sample has been collected. Which of the fol-
Calculate this patient’s alveolar ventilation.
lowing tests can be used to determine the reliability of
A. 4.20 liters/minute the sputum sample?
B. 5.40 liters/minute
A. Ziehl-Neelsen acid-fast stain
C. 6.00 liters/minute
B. gram stain
D. 9.13 liters/minute

100 Chapter 3: Clinical Data

 C. periodic acid-Schiff stain A. 3 to 5
D. Gomori’s methenamine silver B. 5 to 7
C. 7 to 10
IA1f(3) D. 10 to 15
91. A physician asks the CRT to recommend a diagnostic
test that will allow for the measurements Raw and SGaw. Questions #94 and #95 refer to the same patient.
Which of the following tests should the CRT recom-
A 150-lb (IBW) patient has a tidal volume of 500 ml
mend?
and a ventilatory rate of 12 breaths/min.
A. single-breath N2 elimination study
B. bronchoprovocation IA1f(2)
C. body plethysmography 94. Calculate this patient’s minute ventilation.
D. CT scan
A. 1.8 liters/minute
IA1f(2) B. 2.3 liters/minute
C. 4.2 liters/minute
92. What term best describes a patient’s condition that is
D. 6.0 liters/minute
associated with an arterial PCO2 of 25 mm Hg?
A. hypoventilation IA1f(2)
B. tachypnea
C. hyperventilation 95. Calculate this patient’s alveolar minute ventilation. As-
D. hyperpnea sume the absence of dead-space disease.

IA1f(2) A. 1.8 liters/minute

B. 2.3 liters/minute
93. The tidal volume (VT) for a normal healthy individual
C. 4.2 liters/minute
is usually _____ ml/kg of IBW.
D. 6.0 liters/minute

Chapter 3: Clinical Data 101

 STOP
You should stop here to evaluate your performance on the 95 questions relating to matrix sections IA1 and IA2. Use the
Entry-Level Examination Matrix Scoring Form referring to the Clinical Data sections IA1 and IA2 (Table 3-3). After you
evaluate your performance on matrix sections IA1 and IA2, refer to the Clinical Data portion of the NBRC Entry-Level Exam
Matrix in Table 3-4. Then, continue with the Clinical Data assessment.
Table 3-3: Clinical data: Entry-level examination matrix scoring form

Clinical Data Clinical Data Items Clinical Data Content

Content Area Item Number Answered Correctly Area Score

IA1. Review data in the patient 2,4,5,7,8,10,11,12,13,14,16,

record. 19,20,22,23,25,26,27,28,37,
39,42,43,45,46,47,48,49,50,
51,53,54,55,56,57,59,60,61, __  100 = ____%
63,66,68,69,70,71,72,75,76, 65 __  100 = ____%
77,79,80,81,82,83,85,86,89, 95
91,92,93,94,95
IA2. Recommend procedures to 1,3,6,9,15,17,18,21,24,30,31,
obtain additional data. 33,34,38,40,41,44,52,58,62, __  100 = ____%
64,65,67,73,74,78,84,87,88,90 30

102 Chapter 3: Clinical Data

Table 3-4: NBRC Certification Examination for Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
N

N
(4) dead space to tidal volume ratio
I. Select, Review, Obtain, (VD/VT) x
(5) non-invasive monitoring [e.g.,
and Interpret Data
capnography, pulse oximetry,
SETTING: In any patient care set- transcutaneous O2/CO2] x
ting, the respiratory care practi- g. results of cardiovascular monitoring
tioner reviews existing clinical data (1) ECG, blood pressure, heart rate x
and collects or recommends ob- (2) hemodynamic monitoring [e.g.,
taining additional pertinent clinical central venous pressure, cardiac
data. The practitioner interprets all output, pulmonary capillary wedge
data to determine the appropriate- pressure, pulmonary artery pressures,
ness of the prescribed respiratory mixed venous O2, C(a-v̄)O2, shunt
care plan and participates in the studies (Q̇s/Q̇t)] x
development of the plan. h. maternal and perinatal/neonatal history
and data [e.g., Apgar scores, gestational
age, L/S ratio, pre/post-ductal
A. Review existing data in patient record,
oxygenation studies] x x
and recommend diagnostic procedures. 2* 3 0
2. Recommend the following procedures to
1. Review existing data in patient record;
obtain additional data:
a. patient history [e.g., present illness,
a. X-ray of chest and upper airway, CT
admission notes, respiratory care
scan, bronchoscopy, ventilation/
orders, progress notes] x** x
perfusion lung scan, barium swallow x
b. physical examination [e.g., vital signs,
b. Gram stain, culture, and sensitivities x
physical findings] x x
c. spirometry before and/or after
c. lab data [e.g., CBC, chemistries/
bronchodilator, maximum voluntary
electrolytes, coagulation studies,
ventilation, diffusing capacity, functional
Gram stain, culture and sensitivities,
residual capacity, flow-volume loops,
urinalysis] x
body plethysmography, nitrogen
d. pulmonary function and blood gas
washout distribution test, total lung
results x
capacity, CO2 response curve, closing
e. radiologic studies [e.g., X-rays of
volume, airway resistance,
chest/upper airway, CT, MRI] x
bronchoprovocation, maximum
f. monitoring data
inspiratory pressure (MIP), maximum
(1) pulmonary mechanics [e.g.,
expiratory pressure (MEP) x
maximum inspiratory pressure
d. blood gas analysis, insertion of arterial,
(MIP), vital capacity] x
umbilical, and/or central venous
(2) respiratory monitoring [e.g., rate,
pulmonary artery monitoring lines x
tidal volume, minute volume, I:E,
e. lung compliance, airway resistance,
inspiratory and expiratory
lung mechanics, work of breathing x
pressures; flow, volume, and
f. ECG, echocardiography, pulse oximetry,
pressure waveforms] x
transcutaneous O2/CO2 monitoring x
(3) lung compliance, airway resistance,
work of breathing x

*The number in each column is the number of item in that content area and the cognitive level contained in each
examination. For example, in category I.A., two items will be asked at the recall level, three items at the application level,
and no items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the
respective column (Recall, Application, and Analysis).

Chapter 3: Clinical Data 103

 Clinical Data Assessment (continued)
The following 115 questions refer to Entry-Level Examination Matrix section IB1-10.
IB—Collection and evaluation of clinical information
NOTE: You should stop to evaluate your performance on the 115 questions pertaining to the matrix section IB. Please refer
to the NBRC Entry-Level Examination Matrix designations located at the end of the IB content area of the Clinical
Data section to assist you in evaluating your performance on the test items in this section.
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the one that is best in each case, then blacken the corresponding space on the
answer sheet found in the front of this chapter. Good luck.

IB10a A. I, II, III, IV

96. What interpretation of the ECG strip shown in Figure B. II, III only
3-5 should be made by the CRT? C. I, II, III only
D. I, III, IV only
A. sinus bradycardia
B. normal sinus rhythm
C. first degree heart block IB2b
D. atrial flutter 99. The chest radiograph of a mechanically ventilated pa-
tient reveals a small opaque ball in the right hilar re-
IB1b gion, with the remainder of the right hemothorax being
97. The CRT assesses a patient’s capillary refill and finds hypertranslucent. The left hemidiaphragm is displaced
that approximately six seconds elapse before blood inferiorly. Palpation of this patient would likely reveal
flow reappears to a nail bed following blanching of the which of the following findings?
fingernails. What is the significance of this finding?
A. symmetrical chest-wall movement
A. The patient is anemic. B. bilateral reduction in tactile fremitus
B. The patient is hypoxemic. C. tracheal deviation to the left
C. The patient is hypotensive. D. crepitations in the neck region
D. The patient is hypervolemic.
IB9c
IB1a
100. A smoke-inhalation victim arrives in an ambulance at
98. Which of the following features characterize digital
the emergency department. He is breathing an FIO2 of
clubbing?
1.0. An arterial blood gas sample indicates an SaO2 of
I. sponginess of the nail bed 100%. How should the CRT evaluate this result?
II. Angle between the nail bed and proximal skin be-
A. Accept the result as normal.
comes less than 180º.
B. View the result as being underestimated.
III. Ratio of distal phalangeal depth to interpha-
C. View the result as being overestimated.
langeal depth becomes higher than one.
D. Correlate this finding with a pulse oximeter.
IV. increased nail curvature

Figure 3-5: ECG tracing.

104 Chapter 3: Clinical Data

IB4a the following causes might have accounted for this
101. Which of the following respiratory conditions are change?
sometimes associated with stridor? A. The patient was given an albuterol treatment, and
I. asthma the drug has taken effect.
II. laryngotracheobronchitis B. The patient has experienced a decreased cardiac
III. tracheomalacia output.
IV. post-extubation edema C. The patient is rebreathing carbon dioxide.
D. The patient is experiencing a hypermetabolic state.
A. II, III only
B. I, IV only IB5e
C. II, III, IV only
D. I, II, III, IV 106. While interviewing a patient who has mild COPD, the
CRT discovered that the patient has an FEV1 60% of
predicted. The patient reveals her nutritional balance to
IB2a
be 15% protein, 55% carbohydrate, and 30% fat. How
102. Assessment of the pulse should include all of the fol- should this patient be advised about her diet?
lowing factors EXCEPT
A. The present diet is appropriate for a patient with
I. rate. this type of pulmonary disease.
II. strength. B. The diet should consist of 10% protein, 65% car-
III. flow. bohydrate, and 25% fat.
IV. rhythm. C. The diet should entail 25% protein, 40% carbohy-
A. I, II, III only drate, and 35% fat.
B. II, III only D. The diet should be comprised of 5% protein, 65%
C. I only carbohydrate, and 30% fat.
D. III only
IB1a
IB1b 107. What clinical finding would you expect to observe in a
103. Which of the following signs represent a fairly sensi- patient who has a hemoglobin concentration of 15 g%
tive indication of respiratory distress in infants but is of which only 9 g% in total circulation is saturated
usually apparent in adults (only when severe abnor- with oxygen?
mality is present)? A. cyanosis
A. cyanosis B. peripheral edema
B. tachypnea C. poor capillary refill
C. stridor D. digital clubbing
D. retractions
IB1b
IB8a 108. Which of the following findings is suggestive of a non-
104. A four-year-old child arrives at the emergency depart- functional diaphragm?
ment with a high fever, marked respiratory distress, A. nasal flaring and sternal retractions
and drooling. What diagnostic procedures should the B. use of accessory muscles of ventilation
CRT recommend? C. tracheal deviation
D. gentle abdominal movement with respiration
A. arterial blood gas
B. chest radiograph
C. bronchoscopy
IB10a
D. lateral neck radiograph 109. What interpretation of the ECG strip shown in Figure
3-6 should be made by the CRT?
IB9a A. sinus tachycardia
105. A mechanically ventilated patient has been monitored B. ventricular fibrillation
via capnography. The patient’s PETCO2 measures 38 C. ventricular tachycardia
torr. Suddenly, the PETCO2 now reads 18 torr. Which of D. atrial fibrillation

Chapter 3: Clinical Data 105

 Figure 3-6: ECG tracing.

IB9b A. pulsus paradoxus

110. Which of the following descriptions represents the B. respiratory alternans
measurement of the tidal volume? C. abdominal paradox
D. pulsus alternans
A. the volume of gas inspired in one minute
B. the volume of gas exhaled during a forceful exha- IB9d
lation
114. While performing a ventilator check, the CRT obtains
C. the volume of gas inspired during a forceful in-
the following data:
spiration
D. the volume of gas exhaled during normal breath- VT: 600 cc
ing peak airway pressure: 25 cm H2O
plateau pressure: 17 cm H2O
IB1a PEEP: 5 cm H2O
111. The anomaly illustrated in Figure 3-7 is called: Calculate this patient’s static compliance.
A. 0.075 L/cm H2O
B. 0.050 L/cm H2O
C. 0.035 L/cm H2O
D. 0.030 L/cm H2O

IB1a
115. Cyanosis might be apparent whenever ______ g% of
Figure 3-7 reduced hemoglobin exist.
A. cor pulmonale A. 1.5
B. clubbing of the digits B. 5.0
C. pedal edema C. 15.0
D. polydactyly D. 25.0

IB7e IB1b
112. Which of the following conditions causes blunting of 116. Which of the following questions would be useful to
the costophrenic angle? obtain patient information related to sputum produc-
tion?
A. pulmonary nodules
B. atelectasis I. “Do you cough up a lot of secretions?”
C. pulmonary interstitial emphysema II. “What color are your secretions?”
D. pleural effusion III. “When is your cough productive?”
IV. “How long have you had a productive cough?”
IB4c V. “Do your secretions have an odor?”
113. While obtaining the blood pressure of a patient who is A. I, II, V only
having an acute asthmatic episode in the emergency de- B. II, III, V only
partment, the CRT notes that the patient’s systolic pres- C. I, II, III, IV only
sure decreases 10 torr during each of the patient’s D. II, III, IV, V only
inspiratory efforts. What is this finding called?

106 Chapter 3: Clinical Data

IB3 IB7b
117. While performing a physical chest examination on a 121. A patient’s chest X-rays reveal the following findings:
patient, the CRT hears a dull percussion note. Which of the
—large lung volumes
following conditions is likely responsible for this finding?
—increased anterior air space (lateral view)
I. pulmonary consolidation —flattened diaphragms
II. subcutaneous emphysema —enlarged intercostal spaces
III. pleural effusion
Which of the following pulmonary conditions is con-
IV. air trapping
sistent with these radiographic features?
A. I, II, IV only
A. pneumothorax
B. I, II, III only
B. hyperinflation
C. I, III only
C. interstitial pulmonary disease
D. III, IV only
D. pleural effusion
IB8a
IB9e
118. Which of the following disease entities display the
122. A patient complains of the following symptoms:
steeple sign via neck radiography?
—excessive daytime fatigue
I. croup
—headaches upon awakening
II. laryngomalacia
—decreased ability to concentrate
III. epiglotittis
—loss of memory
IV. subglottic stenosis
Which of the following tests is appropriate for this pa-
A. II, IV only
tient?
B. I, IV only
C. II, III, IV only A. bronchoscopy
D. I, II, III only B. pre- and post-bronchodilator study
C. sleep study
IB4b D. bronchoprovocation
119. Which of the following heart sounds would the CRT
expect to hear during auscultation of the heart of a IB10c
COPD patient who has cor pulmonale? 123. The CRT performed a shunt study on a nonfebrile pa-
tient who was referred to the cardiopulmonary lab for
A. P2
this test. The patient claims to have “difficulty breath-
B. A2
ing when she does simple tasks around her house, such
C. M1
as throwing out the garbage, walking the dog, and
D. S1
climbing one flight of stairs.” Her arterial blood gas
analysis, conducted 30 minutes following her breath-
IB4a ing 100% oxygen, reveals the following data.
120. While performing auscultation on the chest of a pa-
tient, the CRT hears diminished breath sounds over the PB 760 torr
thorax. Which of the following conditions are consis- PaO2 560 torr
tent with these findings? PaCO2 42 torr
pH 7.40
I. pulmonary emphysema HCO 3̄ 25 mEq/L
II. gross obesity B.E. +1 mEq/L
III. pulmonary embolism
IV. atelectasis The patient has a normal cardiac output and normal
perfusion status. Her oxygen consumption is 250
A. I, II only ml/min, and her CO2 production is 200 ml/min. Based
B. III, IV only on these data and the arterial blood gas analysis, the
C. I, II, IV only calculated shunt fraction is 0.06.
D. I, II, III, IV
How should the CRT interpret this result?

Chapter 3: Clinical Data 107

 A. inconclusive IB2b
B. abnormally high 128. Auscultation of the chest of a mechanically ventilated
C. abnormally low patient reveals a marked decrease in breath sounds on
D. normal the left; however, both lungs remain clear. The CRT
notes that the endotracheal tube appears to have been re-
IB7c taped since the last ventilator check. Palpation of the
124. Upon reviewing the chest roentgenogram of a patient chest reveals decreased chest excursion on the left.
who has just had a pulmonary artery catheter inserted, Which of the following situations might have occurred?
the CRT notices that the catheter tip resides near the
A. The cuff on the endotracheal tube has developed a
right mediastinal border. What action must be taken in
leak.
response to this radiographic finding?
B. The endotracheal tube has slipped into the right
A. No action is necessary, because the catheter’s tip mainstem bronchus.
is correctly situated. C. The patient has developed a humidity deficit.
B. Advance the catheter tip farther out into the pul- D. Too much volume has been injected into the cuff
monary artery. of the endotracheal tube.
C. Withdraw the catheter tip to just outside the right
ventricle. IB7b
D. Advance the catheter tip to just beyond the right
129. A patient’s chest radiograph reveals pulmonary infil-
mediastinal border.
trates and consolidation. The patient’s right heart border
is blurred. Where is the consolidation likely located?
IB8a
125. Which lateral neck X-ray finding(s) is(are) character- A. right upper lobe
istic of epiglotittis? B. left lower lobe
C. right middle lobe
I. steeple sign D. right lower lobe
II. ballooning hypopharynx
III. thumb sign IB1a
A. I only 130. The CRT is performing a chest physical examination on
B. III only a patient who states, “I’m having trouble breathing when
C. II, III only I do things around the house.” Inspection reveals a trans-
D. I, III only verse chest wall diameter greater than the A-P diameter.
The ribs are at a 45-degree angle in relation to the spine.
IB1a The patient’s stomach moves out slightly with each in-
126. The CRT observes that a patient has swelling from the spiration. These findings are consistent with a(n)
ankles to just below the knees. What type of cardio- A. obstructive abnormality.
vascular problem does this finding suggest? B. restrictive abnormality.
A. right ventricular failure C. mixed condition.
B. left ventricular failure D. normal condition.
C. aortic insufficiency
D. first-degree heart block IB7d
131. Hyperinflation therapy is being given to a post-op tho-
IB1b racotomy patient in order to reverse atelectasis. Which
127. During inspection of a patient’s thorax, the CRT no- of the following radiographic signs indicate the reso-
tices that the anteroposterior chest diameter is larger lution of the atelectasis?
than its transverse diameter. What is the significance of
I. hyperinflation of adjacent lobes or contralateral
this finding?
lung
A. This observation is a normal finding. II. absence of air bronchograms
B. This observation indicates a restrictive abnormality. III. increased local radiolucency
C. This finding represents an obstructive disorder. IV. increased size of rib interspaces over the affected
D. This finding has no clinical significance. lung

108 Chapter 3: Clinical Data

 A. I, II only IB1b
B. III, IV only 136. The CRT enters the NICU and notices a newborn in-
C. II, III, IV only fant demonstrating nasal flaring with each inspiratory
D. I, II, III, IV effort. What is the significance of this sign?
A. The infant requires supplemental oxygen.
IB1a
B. The infant has respiratory distress syndrome.
132. Which of the following pulmonary diseases are often C. The infant is attempting to achieve a larger tidal
associated with digital clubbing? volume.
I. pulmonary edema D. This activity is the newborn’s method of sighing.
II. bronchogenic carcinoma
III. bronchiectasis IB7a
IV. congenital heart disease 137. A patient has just been endotracheally intubated. The
chest X-ray assessing the placement of the endotracheal
A. I, IV only
tube was obtained while the patient’s neck was flexed
B. I, II, III only
and shows that the tube’s distal tip is 1 cm beyond the
C. II, III, IV only
carina on the right. What should the CRT do at this time?
D. I, II, III, IV
A. Request another chest radiograph.
IB9b B. Add 1 cc of air into the cuff of the endotracheal
tube.
133. A patient who has an IBW of 160 lbs is breathing 16
C. Withdraw the tube 2 to 3 cm and resecure the tube.
times per minute. The patient has an alveolar ventila-
D. Place the patient’s neck in a neutral position.
tion of 4.0 liters per minute. Determine this patient’s
minute ventilation.
IB1a
A. 1,440 liters/min. 138. A patient claims to sweat a lot during the night while
B. 2,560 liters/min. sleeping. With which of the following diseases is this
C. 3,670 liters/min. symptom (diaphoresis) often associated?
D. 6,560 liters/min.
A. tuberculosis
B. pneumonia
IB8b
C. amyotrophic lateral sclerosis
134. A patient’s chest radiograph indicates an elevation of D. cystic fibrosis
the right hemidiaphragm. Which of the following con-
ditions is likely the cause? IB4a
A. pulmonary effusion in the left lung 139. A loud, continuous, high-pitched sound heard during
B. pulmonary fibrosis in the right lung auscultation of the larynx and trachea is called
C. pneumothorax on the right side
A. wheezing.
D. neoplasm obstructing air flow in the left lung
B. rhonchi.
C. stridor.
IB10e D. crackles.
135. A polysomnogram documented that a patient has ob-
structive sleep apnea. After this condition is diagnosed, IB1c
what is the next action that should be taken to treat the 140. In a dark room, a fiberoptic light is placed against the
patient? thorax of a neonate. A lighted “halo” is observed
A. Train the patient to sleep on his side, rather than around the point of contact with the neonate’s skin.
on his back. What condition is likely present based on this finding?
B. Initiate nocturnal CPAP breathing. A. atelectasis
C. Administer nocturnal oxygen via a nasal cannula. B. pneumothorax
D. Identify the CPAP level, eliminating the snoring C. consolidation
and the sleep apnea. D. a normal finding

Chapter 3: Clinical Data 109

IB10a A. by inspection of the nail bed color
141. A patient who does not smoke is receiving supplemen- B. by inspection of the mucous membranes
tal oxygen and has a pulse oximeter probe attached to C. by inspection of the skin color
her finger. The pulse oximeter indicates 100%. What is D. by inspection of the capillary refill time
the patient’s corresponding arterial PO2?
IB1b
A. 120 torr
145. Which of the following chest configurations would
B. 100 torr
you expect to observe in a patient who has pulmonary
C. 95 torr
emphysema?
D. The PO2 cannot be determined.
A. pectus carinatum
IB9c B. pectus excavatum
142. A patient has a PAC inserted, as denoted by the PAC C. barrel chest
waveform in Figure 3-8. D. kyphoscoliosis

The CRT has been requested to obtain a mixed venous IB7e

blood sample from this patient. How should the CRT
146. On admission, a patient having left ventricular failure
proceed at this time?
displays the following chest radiographic features.
A. Obtain the mixed venous blood sample as or-
—enlarged, prominent pulmonary vasculature in the
dered.
upper lobes
B. Pull the PAC out of the wedged position into the
—right-sided pleural effusion
pulmonary artery, then collect the sample.
—Kerley B lines along the right base
C. Advance the PAC out of the right ventricle into
the pulmonary artery, then collect the sample. Two days later, this patient’s chest X-ray reveals the
D. Obtain the mixed venous blood sample from a following findings.
vein in the patient’s right arm.
—barely visible pulmonary vessels in the upper lobes
—prominent pulmonary vessels in the lower lobes
IB7c —disappearance of right-sided pleural effusion
143. Upon reviewing the chest radiograph of a patient who —disappearance of Kerley B lines
has just had a central venous pressure catheter in-
serted, the CRT notices that the tip of the catheter is What has accounted for the radiographic changes in
situated against the wall of the superior vena cava. this patient over the course of the two days following
What action needs to be taken because of this finding? admission?

A. No action is necessary, because the catheter tip is A. The patient had a pneumothorax that was eventu-
correctly located. ally relieved.
B. The catheter tip needs to be withdrawn until it B. The patient had pulmonary edema that resolved.
leaves the superior vena cava. C. The patient had lobar pneumonia that resolved.
C. The catheter needs to be adjusted until the tip is D. The patient had a foreign body aspiration that was
situated away from the vessel wall. removed.
D. The catheter tip needs to be advanced until it en-
ters the right ventricle. IB2b
147. While palpating the thorax of a one-day, post-op
IB1a lobectomy patient, the CRT hears a crackling sound
144. How can the CRT most reliably identify that a patient and feels a crackling sensation. Which of the following
has cyanosis? conditions is most likely present?

15
mm Hg

10

0
Figure 3-8: Pulmonary Artery Catheter (PAC) waveform.

110 Chapter 3: Clinical Data

 A. pneumothorax A. right ventricular failure
B. atelectasis B. left ventricular failure
C. subcutaneous emphysema C. pulmonary embolism
D. pleural effusion D. asthma

IB1b IB10a
148. Upon visually inspecting the chest of a 59-year-old 153. The capnogram shown in Figure 3-9 was obtained
factory worker who has smoked two packs of ciga- from a patient who was receiving mechanical ventila-
rettes a day for 40 years, the CRT notices that the pa- tory support.
tient’s chest appears to be in a permanent state of

PetCO2 (mm Hg)

inspiration, while his ribs are held in a horizontal po-
40
sition. Further inspection reveals that the transverse
chest diameter is almost equal to its anteroposterior di-
ameter. While he breathes, the patient’s thorax moves 20
up and down vertically as a whole. Which description
best applies to the appearance of this patient’s chest? 0

A. bucket-handle movement
Figure 3-9: Capnogram.
B. Pendelluft breathing
C. barrel chest What does the capnogram reflect?
D. pectus carinatum
A. hyperthermia
B. hyperventilation
IB10a C. increased cardiac output
149. A patient is being monitored via capnography during D. kinked or obstructed ventilator tubing
CPR. What might account for a PETCO2 value rising
and approaching that of the patient’s PaCO2? IB4a
A. an increase in physiologic dead space 154. While performing auscultation on the chest of a pa-
B. hyperventilation tient, the CRT hears bronchial breath sounds where
C. another cardiac arrest normal vesicular breath sounds were heard. Which of
D. an increased cardiac output the following conditions could account for this auscul-
tatory finding?
IB1b I. pleural effusion
150. How would a patient possibly describe sputum that is II. atelectasis
tenacious? III. pneumonia
IV. pneumothorax
A. frothy
B. extremely sticky A. III, IV only
C. fetid B. II, IV only
D. copious C. II, III only
D. I, II only
IB9a
151. What method of oxygen analysis is appropriate when IB1b
a patient has a PaO2 of 125 torr? 155. Which of the following clinical signs would the CRT no-
tice in an infant who is experiencing respiratory distress?
A. co-oximetry
B. blood-gas analysis I. grunting
C. pulse oximetry II. retractions
D. spectrophotometry III. tachypnea
IV. nasal flaring
IB1a A. I, II only
152. During inspection of a patient, the CRT notices B. I, II, III only
swelling in both legs to a level just below the knees. C. II, III only
What condition is the likely cause of this presentation? D. I, II, III, IV

Chapter 3: Clinical Data 111

IB1b IB1b
156. Which of the following signs can be assessed while 160. Periodic, prolonged, forceful coughing episodes can
observing the general appearance of the patient? be best described as:
I. diaphoresis A. acute
II. accessory ventilatory muscle use B. chronic
III. ventilatory pattern C. paroxysmal
IV. vital signs D. hacking
V. hypoxemia
A. I, III only IB3
B. II, III, IV only 161. While percussing a patient’s chest, the CRT hears a
C. I, II, IV, V only dull note over the lung bases. Which of the following
D. I, II, III only statements best describes this finding?
A. Dull percussion over the basilar areas of the lungs
IB4a is normal during exhalation.
157. During a physical examination of the chest, the CRT B. Dull percussion is indicative of increased air in
hears discontinuous, high-pitched bubbling sounds on the lungs.
inspiration. Which of the following conditions are fre- C. Dull percussion occurs over an area of lung con-
quently associated with this type breath sound? solidation or fluid accumulation.
D. Dull percussion indicates the presence of air trap-
I. pneumothorax ping.
II. pleural effusion
III. pulmonary edema
IB4a
IV. pneumonia
162. Immediately following endotracheal intubation, the pa-
A. I, II only tient is noted to have diminished air entry on ausculta-
B. III, IV only tion of the left chest. Which of the following conditions
C. II, III, IV only is the likely cause of this condition?
D. I, II, IV only
A. pneumothorax
IB9c B. endobronchial intubation
C. a mucous plug
158. When calculating V̇A, what should the CRT use to mea- D. lobar atelectasis
sure the CO2 in the exhaled gas when the patient has
severe pulmonary emphysema?
IB2b
A. capnography 163. Which of the following pulmonary conditions usually
B. arterial blood gas analysis cause bilateral reduction of thoracic expansion?
C. infrared absorber
D. gas chromatography I. COPD
II. neuromuscular disease
IB2b III. atelectasis
IV. right middle-lobe pneumonia
159. While palpating the chest wall of a febrile patient who
coughs up rusty-colored sputum and complains of A. I, III only
sharp, piercing pain when taking a deep breath, the B. I, II only
CRT finds an absent vocal fremitus. Which of the fol- C. II, III, IV only
lowing conditions is most likely present? D. I, II, IV only
A. pulmonary emphysema
IB5a
B. pneumonia
C. atelectasis 164. Which of the following emotional states may be in-
D. lung tumor dicative of illness or pain?

112 Chapter 3: Clinical Data

 I. fear IB2b
II. anxiety 168. While performing a chest physical examination on a
III. depression 60-kg adult patient, the CRT observes the left hemitho-
IV. anger rax to move 3 cm and the right hemithorax to move 3
A. I only cm. What do these findings indicate?
B. II, III only A. neuromuscular disease
C. I, II, III only B. COPD
D. I, II, III, IV C. right lower-lobe consolidation
D. normal chest wall expansion
IB4a
165. While conducting a physical examination of a patient’s
chest, the CRT hears rhonchi during expiration via
IB4a
auscultation. Which of the following pulmonary con- 169. Which of the following terms describe vibrations pro-
ditions are often associated with these findings? duced by air at a high velocity moving through the air-
way?
I. bronchospasm
II. pulmonary fibrosis A. rales
III. partial airway obstruction with thick secretions B. stridor
IV. atelectasis C. rhonchi
D. wheezing
A. I, III only
B. I, II only
C. I, II, IV only IB1b
D. II, III, IV only 170. Which of the following conditions is associated with
the presence of intercostal and sternal retractions?
IB5b
I. decreased lung compliance
166. Which of the following situations would indicate that II. severe upper-airway obstruction
a patient is suffering from orthopnea? III. severe restrictive disease
A. The patient avoids shortness of breath by prop- IV. decreased pulmonary elastance
ping a pillow under his back. A. II, III only
B. The patient experiences waking episodes during B. I, IV only
the night because of dyspnea. C. II, III, IV only
C. The patient experiences swelling of the hands and D. I, II, III only
feet upon rising.
D. The patient awakens with fluttering or palpita-
tions in the chest. IB10b
171. The CRT obtains a vital capacity of 220 ml and a tidal
IB7e volume of 200 ml on a Guillain-Barré patient. These
167. A patient’s chest radiograph demonstrates the follow- findings represent
ing findings: A. tachypnea.
• A blunted costophrenic angle on the right side B. a reduction in ventilatory reserve.
• A partially obscured right hemidiaphragm C. normal lung volumes.
D. an associated lung pathology.
Which of the following lung conditions is consistent
with these radiologic findings?
IB10d
A. pleural effusion
B. atelectasis 172. Data from four valid measurements of the FVC ob-
C. pulmonary infiltrates tained from the same subject are listed in Table 3-5.
D. consolidation

Chapter 3: Clinical Data 113

Table 3-5 of the thorax, accompanied by mediastinal and tracheal
deviation to the right . . .” How should the CRT inter-
FEF25%–75% pret these latest radiographic findings?
Trial FVC (liters) FEV1 (liters) (liters/second)
A. The patient is experiencing consolidation on the
1 4.40 3.10 2.46 right side of the chest.
2 4.20 3.60 2.56
B. The patient has developed a right-sided pneu-
3 4.50 3.45 2.70
mothorax.
4 4.35 3.35 2.75
C. An empyema has developed in the patient’s right
chest.
Which FEF25%–75% value should be reported? D. The patient has an atelectatic right lung.
A. 2.46 liters/second
B. 2.56 liters/second IB9f
C. 2.70 liters/second 176. To assure adequate tracheal blood flow, the cuffs of en-
D. 2.75 liters/second dotracheal tubes should be maintained at _____ cm
H2O or less.
IB10f A. 60
173. A CRT is using an in-line pressure monitor to measure B. 40
the cuff pressure of an intubated patient. The cuff pres- C. 30
sure indicates 27 mm Hg. Based on this pressure, which D. 15
of the following actions should be taken by the CRT?
A. Immediately increase the cuff pressure to 30 mm IB9c
Hg. 177. A patient who has a history of chronic bronchitis en-
B. Slowly deflate the cuff until a small leak is heard ters the hospital with an exacerbation of her disease.
around the cuff at the PIP. She is administered oxygen at 2 liters/minute via a
C. Reintubate the patient with a larger endotracheal nasal cannula. The CRT wishes to monitor the effect of
tube. the oxygen therapy on her hypoxic drive. The best
D. Reduce the cuff pressure to 10 to 12 mm Hg. method of monitoring the adequacy of her ventilation
would be to perform which of the following tasks?
IB4a A. Obtain an arterial blood gas.
174. While conducting a physical examination of a patient’s B. Employ pulse oximetry.
chest, the CRT hears inspiratory and expiratory wheez- C. Implement PtcO2 monitoring.
ing. Which of the following conditions can cause this D. Procure a mixed venous oxygen sample.
finding?
I. bronchospasm IB4b
II. mucosal edema 178. What aspect of an ECG tracing is commonly associ-
III. pneumothorax ated with myocardial ischemia?
IV. atelectasis
A. ST segment depression
A. II, III, IV only B. widened QRS complexes
B. I, III only C. lengthened P-R interval
C. II, IV only D. irregularly spaced QRS complexes
D. I, II only
IB5b
IB7b 179. While being interviewed, a patient states, “I have re-
175. While reviewing chest radiographic findings in a pa- cently awakened during the night breathless. It goes
tient’s chart, the CRT notices that the latest inclusion away when I sit up in bed.” Which of the following
indicates “. . . complete opacification of the right side terms best describes this patient’s experience?

114 Chapter 3: Clinical Data

 A. dyspnea IB10c
B. platypnea 184. A 25-year-old patient experiences a change in the
C. orthopnea VD/VT ratio from 0.3 to 0.5 immediately following the
D. eupnea initiation of positive pressure mechanical ventilation.
How should the CRT interpret these data?
IB10c
A. The patient has developed increased intrapulmonary
180. The CRT notices that a 24-year-old mechanically ven- shunting.
tilated patient has a shunt fraction of 0.4. What kind of B. The patient has experienced a normalization of
P(A-a)O2 would the CRT expect to see this patient dis- the lung’s overall V̇/Q̇ ratio.
play while breathing 100% O2? C. Mechanical ventilation causes an increased dead-
A. a normal P(A-a)O2 space ventilation.
B. a widened P(A-a)O2 D. The anatomic dead space has increased.
C. a narrowed P(A-a)O2
D. Insufficient data are available to forecast the IB4a
P(A-a)O2. 185. The CRT is assessing a 20-year-old man in the emer-
gency room. Upon auscultation, high-pitched sounds are
IB4a heard during the expiratory phase throughout both lung
181. Which of the following adventitious sounds is heard fields. These abnormal sounds are described as follows:
with croup, epiglottitis, and post-extubation edema? A. rhonchi
A. rhonchus B. rales
B. pleural friction rub C. wheezes
C. stridor D. crackles
D. wheeze
IB9e
IB9c 186. When performing respiratory impedance plethysmog-
raphy, two coils of insulated wire are sewn into elastic
182. When performing a VD/VT study on a COPD patient,
cloth bands in a sinusoidal manner. Over what area(s)
why should the CRT not use the PETCO2 to substitute
of the body are the sinusoidal bands placed?
for the patient’s PaCO2?
A. chest wall and abdomen
A. because the PETCO2 value fluctuates too much in B. abdomen
a COPD patient C. chest wall
B. because the PaCO2 is easier to measure in a D. airway opening
COPD patient
C. because the PETCO2 value inaccurately represents IB9d
the PaCO2 in a COPD patient
D. because a COPD patient has a high V̇CO2 187. Having a subject inspire to total lung capacity, fol-
lowed by a rapid, forceful, complete exhalation, pro-
vides for the measurement of the:
IB5b
183. A patient who complains of “breathlessness while A. FVC
dressing, while walking from the house to get the B. expiratory reserve volume
newspaper on the sidewalk, and while walking up the C. inspiratory capacity
front porch steps” is said to have a(n) D. residual volume

A. obstructive lung disease. IB5b

B. decrease in exercise tolerance. 188. Which of the following terms is most likely to be iden-
C. cardiovascular disease. tified by a patient without a medical background as be-
D. decrease in activities of daily living. ing secretions from the tracheobronchial tree?

Chapter 3: Clinical Data 115

 A. lower respiratory tract secretions IB10b
B. sputum 193. A spontaneously breathing adult patient is found to
C. phlegm have an I:E of 1:4. How should the CRT interpret this
D. spit finding?

IB10c A. The patient likely has chronic obstructive airway

disease.
189. A patient’s arterial blood gas and acid-base results are
B. The patient likely has restrictive airway disease.
shown below.
C. The patient likely has mixed airway disease.
PO2 70mm Hg D. The patient’s I:E ratio is normal.
PCO2 54mm Hg
pH 7.33; HCO 3̄ IB10c
28 mEq/liter
194. The CRT has obtained a mixed venous blood sample
B.E. 4 mEq/liter
from a patient who has had a pulmonary artery
Which of the following interpretations correlates with catheter inserted. The sample was analyzed, and the
these results? Pv̄O2 was found to be 30 torr. Which interpretation(s)
A. compensated respiratory alkalosis can be made based on this Pv̄O2 value?
B. uncompensated metabolic acidosis I. The patient has a low cardiac output.
C. partially compensated metabolic acidosis II. The patient has polycythemia.
D. partially compensated respiratory acidosis III. The patient is experiencing left-to-right shunting.
IV. The sample contained some arterial blood.
IB10b
A. I only
190. Using a Wright’s respirometer on a patient who is be- B. II, III only
ing considered for weaning from mechanical ventila- C. I, III only
tion, the CRT has measured the exhaled volume during D. I, II, III, IV
2.75 minutes of spontaneous breathing. During this
time, 32.7 liters are measured. What is this patient’s
IB4a
spontaneous minute ventilation?
195. Inspiratory stridor might be auscultated in patients
A. 4.8 liters/minute who have which of the following diagnoses?
B. 6.9 liters/minute
C. 11.9 liters/minute I. epiglottitis
D. 32.7 liters/minute II. croup
III. pulmonary embolism
IB4a IV. post-extubation inflammation
191. When documenting breath sounds that were low- A. II, III, IV only
pitched, continuous, and cleared with a cough after a B. I, II, III only
treatment, which of the following descriptions should C. I, III, IV only
be used by the CRT? D. I, II, IV only
A. vesicular breath sounds
IB10c
B. wheezes
C. rhonchi 196. How should the CRT interpret the following arterial
D. rales blood gas and acid-base data obtained from a 56-year-
old patient who is breathing room air?
IB5a PO2 68mm Hg
192. Which of the following activities requires the highest PCO2 52mm Hg
level of patient consciousness? pH 7.39
HCO 3̄ 31 mEq/liter
A. physical movement to painful stimulus B.E. +7 mEq/L
B. ability to follow commands
C. orientation to place A. compensated respiratory acidosis with mild
D. performance of simple math calculations hypoxemia
B. uncompensated metabolic acidosis with no
hypoxemia

116 Chapter 3: Clinical Data

 C. compensated metabolic alkalosis with mild hypoxemia IB6
D. partially compensated respiratory acidosis with no 199. Which of the following teaching techniques are appropri-
hypoxemia ate to use when teaching children therapeutic procedures?

IB10d I. Be repetitious.
II. Use terms that are understandable.
197. The results of three valid measurements of the FVC
III. Teach the parents first.
from the same subject are listed in Table 3-6.
IV. Have the patients actively participate.
Table 3-6 A. III, IV only
FEF25%–75% B. I, II, IV only
Trial FVC (liters) FEV1 (liters) (liters/second) C. I, II, III only
D. I, II, III, IV
1 4.40 3.10 2.46
2 4.20 3.60 2.56 IB3
3 4.50 3.45 2.70
200. While performing percussion during physical assessment
of the chest, the CRT hears resonant sounds. Which of the
However, are these data for the FVC reliable? following conditions is (are) associated with this finding?
A. They are reliable because the largest two FVC I. pneumothorax
measurements do not vary by more than 5%. II. consolidation
B. Reliability exists, because the largest and smallest III. normal lungs
FVC vary by less than 5%. IV. air trapping
C. These data are not reliable, because the largest
A. III only
two FVC measurements vary by more than 5%.
B. IV only
D. Reliability is lacking, because the largest and the
C. I, IV only
smallest FVCs vary by more than 5%.
D. II, III only
IB10c
IB7e
198. While reviewing a patient’s chart, the CRT notices that
The normal chest radiograph shown in Figure 3-10 refers
the most recent room air blood-gas analysis revealed
to questions #201 and #202.
the following data:
201. Which number identifies the costophrenic angle?
PO2 43 torr
PCO2 36 torr A. 11
pH 7.33 B. 8
SO2 70% C. 7
HCO 3̄ 19 mEq/L D. 5
B.E. -5 mEq/L
At the same time the blood sample was obtained, the
IB7e
patient’s SpO2 was 95%. The patient’s ventilatory sta- 202. Which number indicates vascular markings?
tus was found to include the following: A. 6
• ventilatory pattern: regular B. 7
• tidal volume: 600 ml C. 9
• ventilatory rate: 16 breaths/minute D. 10
How should the CRT interpret these data?
IB3
A. An air bubble contaminated the blood sample.
203. When performing percussion on a patient, how can in-
B. The patient should be administered oxygen via a
terference imposed by the two scapulae be minimized?
cannula at 2 liters/minute.
C. The blood gas data reflect venous values. A. Have the patient take a deep breath and hold that
D. The pulse oximeter was out of calibration. breath for 10 seconds.

Chapter 3: Clinical Data 117

 12
12
11
11
11
11
1
11
10
11
4 11
3
2
11
9 11

9 6
11
11

5
11
11

11
13 11
13
11

7 7
8
8

Figure 3-10: Normal chest radiograph.

B. Have the patient exhale slowly to residual volume A. pneumothorax

and hold that breath for five seconds. B. pleural effusion
C. Have the patient raise both arms above the shoul- C. normal breathing
ders. D. atelectasis
D. Have the patient lean forward and hunch his back.
IB3
IB6 206. The CRT is ready to perform percussion on a patient
204. When teaching a patient a psychomotor skill, what who is being evaluated for lung disease. In what order
teaching activity provides the patient with the greatest should the CRT proceed with percussion?
opportunity to perform the task? A. Percussion should be performed from the apex to
A. using visual aids the base on one side of the chest, then from the
B. having the patient practice the skill apex to the base on the other side.
C. telling the patient how to perform the skill B. Percussion should begin at the base and end in the
D. enabling the patient to ask questions about the apex on one side of the thorax, from the base to
task apex on the opposite side.
C. Percussion should be performed on one side of the
IB3 chest, then on the other side in the comparable area.
D. Percussion should begin on the anterior aspect of
205. While performing percussion of the thorax during phys-
one hemithorax, then on the posterior aspect
ical chest assessment, the CRT hears hyperresonant
of the same hemithorax, followed by percussion
percussion notes over the left lower lobe. What is the
of the opposite lung.
significance of this finding?

118 Chapter 3: Clinical Data

IB6 IB8
207. What are the domains within which learning occurs? 209. A three-year-old child enters the emergency depart-
ment with a partial upper-airway obstruction, produc-
I. psychomotor domain
ing inspiratory stridor. Which of the following
II. attitudinal domain
diagnostic procedures will assist in differentiating
III. affective domain
croup from epiglottitis?
IV. cognitive domain
A. chest radiography
A. II, IV only
B. lateral neck radiograph
B. I, II, III only
C. responsiveness to a bronchodilator
C. I, III, IV only
D. lung scan
D. I, II, III, IV

IB6
IB6
210. A patient who has been recently diagnosed with
208. A recent post-operative thoracotomy patient is experi-
asthma will be leaving the hospital in a couple days.
encing incisional pain as the CRT is discussing the
Which of the following components need to comprise
goals of incentive spirometry with the patient. What
a lesson plan for teaching this patient to properly use
patient need must first be addressed before learning
an MDI, which dispenses a beta-2 agonist?
can take place?
I. when the MDI should be used
A. The patient must understand the disease process
II. how to add a spacer to the system
that warranted the surgery.
III. why the MDI is used
B. The patient must know the difference between a
IV. how the medication acts on the bronchial smooth
flow- and a volume-incentive spirometer.
muscle
C. The patient must have pain medication.
D. The patient must know how incentive spirometry A. I, IV only
will improve his condition. B. II, III only
C. I, II, III only
D. I, II, III, IV

Chapter 3: Clinical Data 119

 STOP
You should stop here to evaluate your performance on the 115 questions relating to the matrix section IB1-10. Use the Entry-
Level Examination Matrix Scoring Form referring to Clinical Data Sections IB1 through IB10 (Table 3-7). Then, refer to the
Clinical Data portion of the NBRC Entry-Level Exam Matrix in Table 3-8. After you evaluate your performance on matrix sec-
tions IB1-10, you should continue with the Clinical Data assessment.
Table 3-7: Clinical Data: Entry-Level Expansion Matrix Scoring Form

Clinical Data Clinical Data Items Clinical Data Content

Content Area Item Number Answered Correctly Area Score

IB1. Assess the patient’s cardio- 97, 98, 103, 107, 108, 111, 115, __  100 = ____%
pulmonary status by 116, 126, 127, 130, 132, 136, 25
inspection 138, 140, 144, 145, 148, 150,
152, 155, 156, 160, 170, 206
IB2. Assess the patient’s cardio- 99, 102, 128, 147, 159, 163, __  100 = ____%
pulmonary status by 168 7
palpation.
IB3. Assess the patient’s cardio- 117, 161, 200, 203, 205 __  100 = ____%
pulmonary status by 5
percussion.
IB4. Assess the patient’s cardio- 101, 113, 119, 120, 139, 154, __  100 = ____%
pulmonary status by 181, 185, 157, 162, 165, 169, 16
auscultation. 174, 178, 191, 195
IB5. Interview the patient. 106, 164, 166, 179, 183, 188, __  100 = ____% ___  100 = ____%
192 7 115
IB6. Assess the patient’s learning 199, 202, 204, 208, 210 __  100 = ____%
needs. 5
IB7. Review chest X-rays. 112, 121, 124, 129, 131, 137, __  100 = ____%
143, 146, 167, 175, 201, 207 12
IB8. Review lateral neck X-ray. 104, 118, 125, 134, 209 __  100 = ____%
5
IB9. Perform bedside procedures. 100, 105, 110, 114, 122, 133, __  100 = ____%
142, 151, 158, 176, 177, 182, 14
186, 187
IB10. Interpret results of bedside 96, 109, 123, 135, 141, 149, __  100 = ____%
procedures. 153, 171, 172, 173, 180, 184, 19
189, 190, 193, 194, 196, 197,
198

120 Chapter 3: Clinical Data

Table 3-8: NBRC Certification Examination for Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
4. Assess patient’s overall cardiopulmonary

N
I. Select, Review, Obtain, status by auscultation to determine the
presence of:
and Interpret Data a. breath sounds [e.g., normal, bilateral,
SETTING: In any patient care set- increased, decreased, absent, unequal,
ting, the respiratory care practi- rhonchi or crackles (rales), wheezing,
tioner reviews existing clinical data stridor, friction rub] x
and collects or recommends ob- b. heart sounds, dysrhythmias, murmurs,
taining additional pertinent clinical bruits
data. The practitioner interprets all c. blood pressure x
data to determine the appropriate- 5. Interview patient to determine:
ness of the prescribed respiratory a. level of consciousness, orientation to
care plan and participates in the time, place, and person, emotional state,
development of the plan. ability to cooperate x
b. presence of dyspnea and/or orthopnea,
work of breathing, sputum production,
B. Collect and evaluate clinical information. 3 7 0
exercise tolerance, and activities of
1. Assess patient’s overall cardiopulmonary
daily living x
status by inspection to determine:
c. physical environment, social support
a. general appearance, muscle wasting,
systems, nutritional status x
venous distention, peripheral edema,
6. Assess patient’s learning needs [e.g., age
diaphoresis, digital clubbing, cyanosis,
and language appropriateness, education
capillary refill x
level, prior disease and medication
b. chest configuration, evidence of
knowledge] x
diaphragmatic movement, breathing
7. Review chest X-ray to determine:
pattern, accessory muscle activity,
a. position of endotracheal or tracheostomy
asymmetrical chest movement,
tube, evidence of endotracheal or
intercostal and/or sternal retractions,
tracheostomy tube cuff hyperinflation x
nasal flaring, character of cough,
b. presence of, or changes in,
amount and character of sputum x
pneumothorax or subcutaneous
c. transillumination of chest, Apgar score,
emphysema, other extra-pulmonary air,
gestational age
consolidation and/or atelectasis,
2. Assess patient’s overall cardiopulmonary
pulmonary infiltrates x
status by palpation to determine:
c. position of chest tube(s), nasogastric
a. heart rate, rhythm, force x
and/or feeding tube, pulmonary artery
b. asymmetrical chest movements, tactile
catheter (Swan-Ganz), pacemaker,
fremitus, crepitus, tenderness, secretions
CVP, and other catheters x x
in the airway, tracheal deviation,
d. presence and position of foreign bodies x
endotracheal tube placement x
e. position of, or changes in,
3. Assess patient’s overall cardiopulmonary
hemidiaphragms, hyperinflation, pleural
status by percussion to determine
fluid, pulmonary edema, mediastinal
diaphragmatic excursion and areas of
shift, patency, and size of major airways x
altered resonance x

*The number in each column is the number of item in that content area and the cognitive level contained in each
examination. For example, in category I.A., two items will be asked at the recall level, three items at the application level,
and no items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the
respective column (Recall, Application, and Analysis).

Chapter 3: Clinical Data 121

Table 3-8: (Continued)

APP
APP

ANA
ANA

LIC
LIC

REC
REC

ATI
ATI

LYS
LYS

ALL
ALL

ON
ON

IS
IS

N
N

N
N
8. Review lateral neck X-ray to determine: 10. Interpret results of bedside procedures
a. presence of epiglottitis and subglottic to determine:
edema x a. ECG, pulse oximetry, transcutaneous
b. presence or position of foreign bodies x O2 /CO2 monitoring, capnography, mass
c. airway narrowing x spectrometry x
9. Perform bedside procedures to determine: b. tidal volume, minute volume, I:E x
a. ECG, pulse oximetry, transcutaneous c. blood gas analysis, P(A-a)O2, alveolar
O2/CO2 monitoring, capnography, ventilation, VD /VT, Q̇s/Q̇t, mixed venous
mass spectrometry x sampling x
b. tidal volume, minute volume, I:E x d. peak flow, maximum inspiratory
c. blood gas analysis, P(A-a)O2, alveolar pressure (MIP), maximum expiratory
ventilation, VD/VD, Q̇s/Q̇t, mixed venous pressure (MEP), forced vital capacity,
sampling x timed forced expiratory volumes [e.g.,
d. peak flow, maximum inspiratory FEV1], lung compliance, lung mechanics x
pressure (MIP), maximum expiratory e. apnea monitoring, sleep studies,
pressure (MEP), forced vital capacity, respiratory impedance plethysmography x
timed forced expiratory volumes [e.g., f. tracheal tube cuff pressure, volume x
FEV1], lung compliance, lung mechanics x
e. apnea monitoring, sleep studies,
respiratory impedance plethysmography x
f. tracheal tube cuff pressure, volume x

122 Chapter 3: Clinical Data

Clinical Data Assessment (continued)
IC—In any clinical care setting, perform procedures and interpret the results.

ID—In any clinical care setting, determine the appropriateness of and participate in the development of
the respiratory care plan and recommend modification.
NOTE: You should stop to evaluate your performance on the 40 questions pertaining to the matrix sections IC and ID.
Please refer to the NBRC Entry-Level Examination Matrix designations located at the end of the IC and ID content
area for Clinical Data to assist you in evaluating your performance on the test items in this section.
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the one that is best in each case, then blacken the corresponding space on the
answer sheet that is found in the front of this chapter. Good luck.

ID1c C. compensated respiratory acidosis without hypox-

211. The following data have been obtained from a 70-year- emia
old male who has been receiving incentive spirometry D. uncompensated metabolic alkalosis without hy-
following upper abdominal surgery: poxemia

ventilatory rate: 23 breaths/minute IC1a

temperature: 100ºF 213. An adult patient is being prepared for bronchoscopy.
heart rate: 105 beats/minute What method of analysis is most suitable to monitor
arterial PO2: 65 torr this patient’s oxygenation status?
auscultation: crackles present in the bases
inspiratory capacity: 25% of predicted A. pulse oximetry
chest X-ray interpretation: right lower lobe at- B. arterial blood gas analysis
electasis with consolidation C. co-oximetry
D. transcutaneous O2 monitoring
Which of the following therapeutic modalities is ap-
propriate at this time? ID2
A. maintaining incentive spirometry 214. A Guillain-Barré syndrome patient has had a number
B. instituting mechanical ventilation of maximum inspiratory pressure measurements per-
C. administering IPPB therapy formed over the last few hours. A summary of these
D. administering bland aerosol therapy data are shown in Table 3-9.
Table 3-9
IC2c
212. A 30-year-old male enters the emergency department Maximum Inspiratory Pressure Measurements
with a broken leg. The CRT notices that the patient is in
Maximum Inspiratory
severe pain and appears upset. The patient has a respira- Time Pressure (MIP)
tory rate of 24 breaths/min. and a heart rate of 112 bpm.
His room air arterial blood gas data are shown as follows. 12:20 P.M. –60 cm H2O
1:15 P.M. –55 cm H2O
PaO2 107 torr 2:20 P.M. –50 cm H2O
PaCO2 26 torr 3:10 P.M. –30 cm H2O
HCO 3̄ 23 mEq/L 4:20 P.M. –15 cm H2O
pH 7.56
SaO2 99%
B.E. -1 mEq/L What therapeutic plan is appropriate to implement at
this time?
Interpret these arterial blood gas data.
A. intubation and mechanical ventilation
A. compensated respiratory alkalosis without hypoxemia B. incentive spirometry
B. uncompensated respiratory alkalosis without hypox- C. oxygen therapy via a high-flow system
emia D. bronchodilator therapy

Chapter 3: Clinical Data 123

IC2b D. A positive test requires simultaneously compress-
215. A one-month-old infant is being monitored via a pulse ing both radial and ulnar arteries and then releas-
oximeter. The SpO2 reads 95%. The infant has a high ing the ulnar first.
concentration of fetal hemoglobin. What will the in-
fant’s actual SaO2 be compared to the SpO2? IC2b
219. The CRT is working on a day-old, full-term neonate.
A. The SaO2 will be significantly lower.
The infant has a bilirubin concentration of 15 mg/dl
B. The SaO2 will be substantially higher.
and is being monitored via a pulse oximeter for oxy-
C. The SaO2 will correlate well with the SpO2.
gen administration through an oxyhood. The SpO2
D. Because the SpO2 readings are spurious, the SaO2
reads 92%. How should the CRT interpret the SpO2?
is unpredictable.
A. The SpO2 should be considered accurate.
IC1b B. The SpO2 will be falsely high.
216. A pulmonary emphysema patient is performing a single- C. The SpO2 will be falsely low.
breath N2 elimination test to determine the distribution D. The correlation will be unpredictable, because
of ventilation. To what lung volume or capacity does SpO2 data will vary.
the patient exhale before inspiring 100% O2 to total
lung capacity? ID1d
220. Despite numerous increases in PEEP and FIO2 levels,
A. functional residual capacity
the CRT is experiencing difficulty improving a me-
B. end-tidal inspiration
chanically ventilated patient’s oxygenation status.
C. residual volume
Which of the following maneuvers might be used to
D. vital capacity
achieve this therapeutic objective?

ID1d A. Institute an inspiratory hold.

B. Apply expiratory resistance.
217. The following data pertain to an 80-kg (IBW) patient
C. Activate the sigh mode.
who has undergone upper abdominal surgery. The pa-
D. Increase the PIP.
tient is receiving CPAP via an endotracheal tube.
MIP: –25 cm H2O after 20 seconds IC1c
VC: 1,600 cc 221. The CRT is preparing to perform an arterial puncture
VT: 625 cc procedure on a patient. The CRT notices a surgical
CPAP: 10 cm H2O shunt used for dialysis appearing on the patient’s left
FIO2: 0.35 arm. What action should the CRT take at this time?
SpO2: 97.5%
A. Consider obtaining the arterial sample from the
What action would be most appropriate for the CRT to right arm.
take at this time? B. Obtain the arterial sample from the surgical
A. Discontinue the CPAP and administer an FIO2 of shunt.
0.3 via an air entrainment mask. C. Perform the arterial puncture on the left radial
B. Extubate the patient and administer O2 via a nasal artery.
cannula at 3 L/min. D. Use a pulse oximeter to measure the SpO2 instead.
C. Decrease the CPAP to 8 cm H2O and maintain the
FIO2 at 0.35. IC2c
D. Make no changes and closely monitor the patient. 222. A 13-year-old girl with a history of asthma enters the
emergency department. Her father stated that she has
IC2a had difficulty breathing for the last two days. Upon in-
218. Before performing an arterial puncture procedure, the spection by the CRT, the child is using her accessory
CRT often performs a modified Allen’s test. What is muscles of ventilation. She has wheezing that can be
the correct interpretation of a modified Allen’s test? heard by the unaided ear. Her room air arterial blood
gases reveal:
A. A positive test indicates that radial arterial blood
flow is sufficient to perfuse the hand. PaO2 37 torr
B. A positive test indicates that pink color returns to PaCO2 24 torr
the hand in fewer than 10 seconds. HCO 3̄ 16 mEq/L
C. A negative test indicates adequate ulnar arterial pH 7.44
blood flow to perfuse the hand. B.E. –8 mEq/L

124 Chapter 3: Clinical Data

 Interpret her arterial blood gas data. A. Airway obstruction is responsive to bronchodila-
tor therapy.
A. compensated respiratory alkalosis with severe hy-
B. Airway obstruction is nonresponsive to bronchodila-
poxemia
tor therapy.
B. uncompensated respiratory alkalosis with severe
C. Inadequate patient effort was exerted; the test
hypoxemia
needs to be repeated.
C. compensated metabolic acidosis with moderate
D. The restrictive disease is nonresponsive bronchodila-
hypoxemia
tor therapy.
D. uncompensated respiratory acidosis with moder-
ate hypoxemia
ID1d
IC1b 227. A carbon monoxide poisoning victim is brought into the
223. For a valid measurement of the peak expiratory flow emergency room wearing a nasal cannula operating at 3
rate, approximately what lung volume should be in the liters/minute. What should the CRT do at this time?
patient’s lungs immediately before making the mea- A. Perform a STAT arterial puncture procedure.
surement? B. Remove the cannula and replace it with a partial
A. total lung capacity rebreathing mask set at 10 liters/minute.
B. vital capacity C. Immediately attach a pulse oximeter probe to the
C. functional residual capacity patient’s finger.
D. inspiratory capacity D. Administer IPPB with 100 % oxygen.

IC2a IC1b
224. What would be the consequence if the percent pre- 228. A 120-cm tall, 11-year-old girl exhibits the following pre-
dicted FEV1 were calculated by using an FEV1 mea- and post-bronchodilator spirometry values (Table 3-11):
sured at ATPS conditions and a predicted normal FEV1 Table 3-11
at BTPS conditions?
Bronchodilator
A. The % predicted normal value would be falsely
low by 6 % to 9 %. Measurement Pre- Post- Predicted
B. The % predicted normal value would be falsely
FVC (liters) 1.13 1.14 1.31
high by 6 % to 9 %. FEV1 (liters) 0.45 0.47 1.21
C. The % predicted normal value would be falsely PEFR (liters/sec) 1.31 1.72 4.87
high by 12 % to 15 %. FEVT (seconds) 7.98 9.13
D. The environmental conditions bear no conse- FEV1% 55% 57% 94%
quence on the results. FEF25–75% (liters/sec) 0.22 0.25 1.95

IC1c
What evaluation can be made concerning the effective-
225. A 40-year-old patient who has a PaO2 of 58 torr on ness of prescribing a bronchodilator for this patient?
room air may be classified as having:
A. The data do not support prescribing a bron-
A. normal oxygenation chodilator for this patient.
B. mild hypoxemia B. No decision should be made, because the data are
C. moderate hypoxemia inconclusive.
D. severe hypoxemia C. Judgment should be reserved until the patient ren-
ders more consistent data.
IC1a
D. A bronchodilator should be prescribed for this pa-
226. A COPD patient has completed a before-and-after bron- tient.
chodilator study. The data are shown in Table 3-10.
Table 3-10 IC2a
229. What is the best indicator to determine the therapeutic
Measurement Before After Predicted effectiveness of a bronchodilator administered via an
FVC 3.10 L 3.70 L 4.10 L MDI?
FEV1 2.15 L 2.80 L 3.40 L A. an increased maximum expiratory pressure
FEF25%–75% 2.90 L/sec 3.50 L/sec 4.50 L/sec B. an increased forced vital capacity
C. an increased FEV25%–75%
What interpretation can be made from these data? D. an increased FEV1

Chapter 3: Clinical Data 125

ID1a positive-pressure ventilator. Identify the point on the
230. An infant who is receiving mechanical ventilation deteri- curve that coincides with the patient’s tidal volume.
orates abruptly. Assessment reveals positive transillumi-
nation of the left chest. What is the most likely diagnosis?
D C
A. left-sided pneumothorax
B. left-sided hemothorax

Volume
C. mucous plug in right mainstem bronchus
D. left-sided diaphragmatic hernia

IC1b B
231. What is the purpose for using 10 % helium in the sin-
A
gle breath diffusing capacity test?
Pressure
A. measuring the total lung capacity Figure 3-11: Pressure-volume waveform.
B. enabling the diffusing capacity to be measured
C. preventing alveolar collapse from the nitrogen be- A. A
ing washed out B. B
D. enabling ventilation through partially obstructed C. C
airways to occur D. D

ID1d IC1c
232. A two-day-old, 24-week-gestation infant has increasing 236. The CRT is paged to the emergency department. The
oxygen requirements accompanied by the accumulation physician there asks the CRT to recommend suitable
of air in the pulmonary interstitium. What modification of instrumentation to measure the SaO2 of a smoke-
respiratory management is most appropriate? inhalation victim. What device should the CRT rec-
ommend?
A. Increase the PIP and decrease the ventilatory rate.
B. Decrease the PEEP. A. arterial blood gas analysis
C. Increase the inspiratory time. B. pulse oximetry
D. Decrease the PIP and increase the ventilatory rate. C. co-oximeter
D. transcutaneous oxygen monitor
IC2c
IC1b
233. A 24-year-old motorcycle accident victim is receiving me-
chanical ventilation and suffers from multiple trauma. The 237. How should a subject be instructed to breathe during a
CRT performs a P(A-a)O2 gradient using an FIO2 1.00. maximum voluntary ventilation maneuver?
The patient’s PaO2 was 60 torr, and the P(A-a)O2 gradient A. Breathe from residual volume to total lung capac-
was 375 torr. What should the CRT suggest at this time? ity for 12 seconds.
A. Maintain the patient’s FIO2 at 1.0. B. Breathe from functional residual capacity to total
B. Add PEEP to the mechanical ventilator. lung capacity for 12 seconds.
C. Determine the patient’s VD/VT ratio. C. Breathe beyond the tidal volume and less than a
D. Perform a shunt study on the patient. vital capacity at a rate of 70 bpm.
D. Breathe within the tidal volume range at a rate of
ID1d 70 bpm.
234. A patient receiving mechanical ventilation has an in-
IC2a
tracranial pressure of 20 torr. What change in the ther-
apeutic plan is indicated? 238. Which of the following pulmonary function data are
consistent with a restrictive lung disease pattern?
A. increasing the FIO2
B. increasing the I:E ratio I. an FVC 70 % of predicted
C. increasing the ventilatory rate II. a TLC 68 % of predicted
D. instituting positive end-expiratory pressure III. an FEV1/FVC ratio of 50 %
A. I, II only
IC2d B. II only
235. The pressure-volume waveform shown in Figure 3-11 C. I, IV only
was obtained from a patient who is breathing via a D. I, II, III

126 Chapter 3: Clinical Data

ID1b Measurment Actual Predicted
239. A physician has written the following respiratory ther-
apy orders: FVC 4.20 L 5.20 L
FEV1 3.50 L 4.15 L
Date Time Order PEFR 8.50 L/sec. 9.00 L/sec.

10-09-00 0930 Deliver 0.5 ml of albuterol Q6 hours via

a hand-held nebulizer. How should the CRT interpret this subject’s perfor-
10-11-00 1430 Add 20 mg Intal to the albuterol treat- mance on the MVV test?
ments Q8 hours.
A. The patient has performed submaximally on the
MVV.
Based on these orders, which of the following actions
B. The patient has performed maximally on the MVV.
would be appropriate?
C. The patient must be short of breath.
A. Add Intal to every other albuterol treatment. D. Patient performance cannot be evaluated via these
B. Give the albuterol Q4 hours and add Intal every data.
other treatment.
C. Refrain from giving all medications until the ID1c
physician can be contacted. 242. A teenage drug-overdose victim is admitted to the
D. Proceed according to the respiratory care depart- emergency department. Arterial blood gas data reveal:
ment policy and procedure manual.
PO2: 59 torr
PCO2: 82 torr
IC1b pH: 7.13
240. A patient performs an FVC maneuver and a slow vital HCO 3̄ : 27 mEq/liter
capacity (SVC) maneuver. The FVC is 700 cc less than B.E.: 3mEq/L
the SVC. What condition accounts for this disparity? SO2: 70%
A. The FVC and SVC can normally be as much as Which acid-base interpretation(s) and/or therapeutic
1.0 liter apart. intervention(s) would be appropriate?
B. A restrictive lung disease is present.
I. This patient has an uncompensated respiratory
C. An obstructive lung disease is present.
acidosis.
D. The patient has a combination of restrictive and
II. Chronic ventilatory failure is present.
obstructive diseases.
III. The patient should likely be intubated and me-
chanically ventilated.
IC2a IV. Nasal CPAP with an FIO2 of 0.50 would be indi-
241. The MVV tracing and the forced expiratory vital ca- cated.
pacity data in Figure 3-12 were obtained from a patient A. I, II, III only
who has an unexplained chronic cough. B. I, III only
C. IV only
D. I, II, IV only
8
7 IC2a
50
6 Breath-by-Breath Tracing 243. While performing a seven-minute nitrogen washout
Volume (liters)

test on a patient who has obstructive lung disease, the

5 40 CRT observes the washout curve shown in Figure 3-13.
Second Maneuver
Volume for the 12

4
How should the CRT interpret this tracing?
Accumulated

30
3
(liters)

A. This tracing is characteristic of patients who have

2 Accumulated Volume obstructive lung disease.
20
1 Tracing B. The tracing indicates that the patient was hyper-
10
ventilating during the test.
0
5 10 15 C. The tracing offers evidence of a possible leak in
Time (seconds) the breathing circuitry.
D. The tracing demonstrates that the patient sighed
Figure 3-12: Maximum Voluntary Ventilation (MVV) tracing. and inhaled a larger volume of gas.

Chapter 3: Clinical Data 127

 N2 A. The patient has a restrictive disease pattern.
80 B. The patient has an obstructive disease pattern.
C. The patient has a combined restrictive-obstructive
disease pattern.
60 D. The patient has a normal volume-time tracing.

40 IC2a
246. The CRT has just completed performing a single-
breath nitrogen elimination test on a patient. The curve
20
generated from this test is shown in Figure 3-15.

0
0 2 4 6 8 60
Volume
Figure 3-13: Seven-minute N2 washout curve from a patient 50
with obstructive lung disease.
40

% N2
ID1b
30
244. A 21-year-old automobile accident victim is receiving
continuous mechanical ventilation with a PEEP of 8 cm 20
H2O. The physician orders that the PEEP be raised to 12
cm H2O. Which of the following physiologic responses 10
indicate that the PEEP is having a deleterious effect?
I. Pulmonary compliance decreases. 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
II. The peak inspiratory pressure increases. Volume (Liters)
III. The plateau pressure increases.
IV. The arterial-venous oxygen content difference in- Figure 3-15: Single-breath N2 elimination curve.
creases.
A. III, IV only How should the CRT interpret these data?
B. I, IV only A. The patient has a gas-distribution pattern charac-
C. I, II only teristic of obstructive lung disease.
D. I, III, IV only B. The patient has a gas-distribution pattern charac-
teristic of restrictive lung disease.
ID1a C. The patient has a gas-distribution pattern that is
245. The volume-time curve in Figure 3-14 was obtained inconclusive.
from a 170-cm, 150-lb adult male who works in a ship- D. The patient has a normal gas-distribution pattern.
building facility and smokes a pack-and-a-half of ciga-
rettes per day. What interpretation should the CRT make?
ID1a
6 247. While palpating the patient’s chest, the CRT notes a de-
creased chest expansion on one side. Noting the asym-
Volume (liters)

5 metrical chest expansion, the CRT reviews the latest

4 chest film. What disease might be present on the radi-
ograph?
3
I. lobar pneumonia
2 II. lobar atelectasis
1 III. large pleural effusion
IV. pneumothorax
1 2 3 4 A. I, II, III, IV
B. II, III, IV only
Time (seconds) C. I, II, III only
Figure 3-14: Forced expiratory volume-time curve. D. I, IV only

128 Chapter 3: Clinical Data

ID1b ID1a
248. A 30-year-old female was recently diagnosed with 249. A patient who has a history of working in shipbuilding
bronchiectasis. The physician has requested respi- should be evaluated for the presence of which occupa-
ratory care services to evaluate the patient for ther- tional lung disease?
apy. The data obtained include the following breath
A. asbestosis
sounds:
B. silicosis
• decreased in right lower lobe C. byssinosis
• rhonchi in right middle lobe D. bagassosis
pulse oximetry: ID1c
• SpO2 85% in right lateral decubitus position 250. A patient who has bilateral pneumonia exhibits the fol-
• SpO2 94% in semi-Fowler’s position lowing room air arterial blood gas data:
chest radiography: PO2 60 torr
PCO2 25 torr
• right middle lobe infiltrates pH 7.53
• right lower lobe infiltrates HCO 3̄20mEq/L
ventilatory mechanics: BE –4mEq/L
• vital capacity greater than 15 ml/kg The patient is also diaphoretic, anxious, and dyspneic.
Her blood pressure is 145/90 torr, heart rate 105
Based on these findings, what therapeutic intervention beats/minute, and ventilatory rate 30 breaths/minute.
should be recommended? Which of the following therapeutic modalities would
A. IPPB be appropriate for this patient?
B. incentive spirometry A. aerosol therapy
C. bronchodilator therapy via an MDI B. chest physiotherapy
D. postural drainage C. oxygen therapy
D. pre- and post-bronchodilator spirometry

Chapter 3: Clinical Data 129

 STOP
You should have completed 40 questions referring to the matrix sections IC and ID. Use the Entry-Level Examina-
tion Matrix Scoring Form (Table 3-12) referring to Clinical Data sections IC and ID.
Be sure to (1) review the matrix items, (2) study the rationales, and (3) read the references. Refer to Table 3-13 to
review the matrix designations pertaining to the Clinical Data sections IC and ID.
Table 3-12: Clinical Data: Entry-Level Examination Matrix Scoring Form
Clinical Data Clinical Data
Content Area Item Number Content Area Score

IC1. Perform the procedures. 213, 216, 221, 223, 225, 226, __  100 = ____%
228, 231, 236, 237, 240 11

IC2. Interpret the results. 212, 215, 218, 219, 222, 224,
229, 233, 235, 238, 241,2 43, __  100 = ____%
246 13 __  100 = ____%
40
ID1. Determine the appropriateness 211, 217, 220, 227, 230, 232,
of the prescribed respiratory 234, 239, 242, 244, 245, 247, __  100 = ____%
care plan and recommend 248, 249, 250 15
modifications (if necessary).

ID2. Participate in the development 214 _  100 = ____%

of the respiratory care plan. 1

130 Chapter 3: Clinical Data

Table 3-13: NBRC Certification Examination for Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
N

N
D. Determine the appropriateness and
I. Select, Review, Obtain, participate in the development of the
respiratory care plan, and recommend
and Interpret Data
modifications. 0 1 4
SETTING: In any patient care set- 1. Determine the appropriateness of the
ting, the respiratory care practi- prescribed respiratory care plan and
tioner reviews existing clinical data recommend modifications where indicated:
and collects or recommends ob- a. analyze available data to determine
taining additional pertinent clinical pathophysiological state x
data. The practitioner interprets all b. review planned therapy to establish
data to determine the appropriate- therapeutic plan x
ness of the prescribed respiratory c. determine appropriateness of prescribed
care plan and participates in the therapy and goals for identified
development of the plan. pathophysiological state x
d. recommend changes in therapeutic
plan if indicated (based on data) x
C. Perform procedures and interpret results. 2 3 0 e. perform respiratory care quality
1. Perform and/or measure the following: assurance x x
a. ECG, pulse oximetry, transcutaneous f. implement quality improvement
O2 /CO2 monitoring x program x x
b. spirometry before and/or after g. review interdisciplinary patient and
bronchodilator, maximum voluntary family care plan x x
ventilation, diffusing capacity, functional 2. Participate in development of respiratory
residual capacity, flow-volume loops, care plan [e.g., case management, develop
body plethysmography, nitrogen washout and apply protocols, disease management
distribution test, total lung capacity, education] x x
CO2 response curve, closing volume,
airway resistance x
c. arterial sampling and blood gas
analysis, co-oximetry, P(A-a)O2 x
d. ventilator flow, volume, and pressure
waveforms, lung compliance x
2. Interpret results of the following:
a. spirometry before and/or after
bronchodilator, maximum voluntary
ventilation, diffusing capacity, functional
residual capacity, flow-volume loops,
body plethysmography, nitrogen washout
distribution test, total lung capacity, CO2
response curve, closing volume, airway
resistance, bronchoprovocation x
b. ECG, pulse oximetry, transcutaneous
O2 /CO2 monitoring x
c. arterial sampling and blood gas
analysis, co-oximetry, P(A-a)O2 x
d. ventilator flow, volume, and pressure
waveforms, lung compliance x

*The number in each column is the number of item in that content area and the cognitive level contained in each
examination. For example, in category I.A., two items will be asked at the recall level, three items at the application level,
and no items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the
respective column (Recall, Application, and Analysis).

Chapter 3: Clinical Data 131

 Chapter 3: Matrix Categories
1. IA2c 49. IA1b 97. IB1b 145. IB1b
2. IA1g(2) 50. IA1a 98. IB1a 146. IB7e
3. IA2a 51. IA1g(2) 99. IB2b 147. IB2b
4. IA1h 52. IA2c 100. IB9c 148. IB1b
5. IA1c 53. IA1f(4) 101. IB4a 149. IB10a
6. IA2f 54. IA1d 102. IB2a 150. IB1b
7. IA1f(2) 55. IA1b 103. IB1b 151. IB9a
8. IA1g(2) 56. IA1f(1) 104. IB8a 152. IB1a
9. IA2a 57. IA1g(2) 105. IB9a 153. IB10a
10. IA1h 58. IA2c 106. IB5e 154. IB4a
11. IA1d 59. IA1f(2) 107. IB1a 155. IB1b
12. IA1f(5) 60. IA1f(4) 108. IB1b 156. IB1b
13. IA1a 61. IA1f(3) 109. IB10a 157. IB4a
14. IA1b 62. IA2c 110. IB9b 158. IB9c
15. IA2c 63. IA1f(5) 111. IB1a 159. IB2b
16. IA1f(2) 64. IA2e 112. IB7e 160. IB1b
17. IA2c 65. IA2d 113. IB4c 161. IB3
18. IA2f 66. IA1g(2) 114. IB9d 162. IB4a
19. IA1f(5) 67. IA2c 115. IB1a 163. IB2b
20. IA1g(1) 68. IA1f(2) 116. IB1b 164. IB5a
21. IA2d 69. IA1f(4) 117. IB3 165. IB4a
22. IA1c 70. IA1b 118. IB8a 166. IB5b
23. IA1a 71. IA1g(2) 119. IB4b 167. IB7e
24. IA2a 72. IA1c 120. IB4a 168. IB2b
25. IA1f(1) 73. IA2c 121. IB7b 169. IB4a
26. IA1f(2) 74. IA2f 122. IB9e 170. IB1b
27. IA1c 75. IA1a 123. IB10c 171. IB10b
28. IA1g(2) 76. IA1f(5) 124. IB7c 172. IB10d
29. IA1f(4) 77. IA1g(1) 125. IB8a 173. IB10f
30. IA2d 78. IA2a 126. IB1a 174. IB4a
31. IA2c 79. IA1h 127. IB1b 175. IB7b
32. IA1f(2) 80. IA1a 128. IB2b 176. IB9f
33. IA2e 81. IA1e 129. IB7b 177. IB9c
34. IA2f 82. IA1b 130. IB1a 178. IB4b
35. IA1f(1) 83. IA1g(1) 131. IB7d 179. IB5b
36. IA1f(5) 84. IA2a 132. IB1a 180. IB10c
37. IA1g(1) 85. IA1f(2) 133. IB9b 181. IB4a
38. IA2a 86. IA1h 134. IB8b 182. IB9c
39. IA1c 87. IA2d 135. IB10e 183. IB5b
40. IA2d 88. IA2a 136. IB1b 184. IB10c
41. IA2c 89. IA1f(2) 137. IB7a 185. IB4a
42. IA1b 90. IA2b 138. IB1a 186. IB9e
43. IA1g(2) 91. IA1f(3) 139. IB4a 187. IB9d
44. IA2d 92. IA1f(2) 140. IB1c 188. IB5b
45. IA1d 93. IA1f(2) 141. IB10a 189. IB10c
46. IA1f(2) 94. IA1f(2) 142. IB9c 190. IB10b
47. IA1h 95. IA1f(2) 143. IB7c 191. IB4a
48. IA1c 96. IB10a 144. IB1a 192. IB5a

132 Chapter 3: Clinical Data

193. IB10b 208. IB6 223. IC1b 238. IC2a
194. IB10c 209. IB8 224. IC2a 239. ID1b
195. IB4a 210. IB6 225. IC1c 240. IC1b
196. IB10c 211. ID1c 226. IC1a 241. IC2a
197. IB10d 212. IC2c 227. ID1d 242. ID1c
198. IB10c 213. IC1a 228. IC1b 243. IC2a
199. IB6 214. ID2 229. IC2a 244. ID1b
200. IB3 215. IC2b 230. ID1a 245. ID1a
201. IB7e 216. IC1b 231. IC1b 246. IC2a
202. IB7e 217. ID1d 232. ID1d 247. ID1a
203. IB3 218. IC2a 233. IC2c 248. ID1b
204. IB6 219. IC2b 234. ID1d 249. ID1a
205. IB3 220. ID1d 235. IC2d 250. ID1c
206. IB3 221. IC1c 236. IC1c
207. IB6 222. IC2c 237. IC1b

Chapter 3: Clinical Data 133

 Clinical Data Answers and Analyses
NOTE: The references listed after each analysis are numbered and keyed to the reference list located at the end of
this section. The first number indicates the text. The second number indicates the page where information
about the question can be found. For example, (1:14, 114) means that on pages 14 and 114 of reference
number 1, information about the question will be found. Frequently, you must read beyond the page num-
ber indicated in order to obtain complete information. Therefore, reference to the question will be found ei-
ther on the page indicated or on subsequent pages.

IA2c in panel F reflects an extrathoracic variable large air-

1. A. The shape of the inspiratory and expiratory limbs of way obstruction characteristic of vocal-cord paralysis.
a flow-volume loop yields significant information about (1:394–397), (6:41, 61), (9:135–136), (11:45–46),
the location of an upper-airway obstruction. The shape (16:233–234).
of the curve can also indicate whether the obstruction is
occurring during inspiration, expiration, or both. IA1g(2)
A flow-volume loop is generated by having a subject 2. A. Mixed venous oxygen values can often be used to
perform an FVC maneuver—and, in the process, ob- evaluate tissue oxygenation. A mixed venous blood
taining a forced expiratory flow-volume tracing. Simi- sample can be obtained via the distal port of a PAC.
larly, when the subject reaches residual volume, he The Sv̄O2 will be determined by the relationship be-
inspires forcefully to total lung capacity and generates tween the oxygen “supply” and the oxygen “demand.”
a forced inspiratory flow-volume curve. Decreases in
Under normal physiologic conditions, a person’s Sv̄O2
either flow (y-axis) or volume (x-axis) provide signifi-
ranges between 70% and 75%. In other words, when
cant clinical information. For example, a decrease in
the resting tissue oxygen delivery (DO2) is normal, the
the flow component indicates airway obstruction, and a
PaO2 falls from 100 torr to a Pv̄O2 of 40 torr (about a
decrease in the volume component signifies restriction.
60 torr difference). Regarding the combined state of O2
Six flow-volume loops are displayed in Figure 3-16. delivery, the SaO2 falls from 97.5% to an Sv̄O2 of 70%
to 75% (about a 22% to 28% change). Keep in mind
Flow-volume loop A is a normal configuration. A re-
that the PO2s are measured in torr and that the SO2s are
strictive lung disease, e.g., kyphoscoliosis, would pro-
measured in %. These are two distinct units.
duce the flow-volume loop depicted in B. Obstructive
lung disease (pulmonary emphysema) is characteristic On the other hand, if the person’s metabolic rate in-
of the tracing shown in panel C. Panel D represents a creases (for example, fever, shivering, seizure activity,
fixed upper-airway obstruction as seen with tracheal and exercise), the tissues demand more oxygen. Con-
stenosis. Tracing E results from a variable intrathoracic sequently, more oxygen is extracted from the arterial
large airway obstruction. The flow-volume loop shown blood. In the process, hemoglobin desaturates more

A. B. C. D. E. F.

Flow

Volume
Figure 3-16: Interpretation of frequently encountered flow-volume loops: (A) normal, (B) restrictive disorder, (C) small airway
obstruction, (D) fixed large airway obstruction, (E) intrathoracic variable large airway obstruction, and (F) extrathoracic variable
large airway obstruction.

134 Chapter 3: Clinical Data

 rapidly. If the cardiac output did not increase, the nor- IA1c
mal mixed venous saturation would decrease more 5. A. Polycythemia is defined as an increased hemoglo-
than it normally does (i.e., greater than 70%). bin concentration or hematocrit. Table 3-14 provides
If the cardiac output increased, however, more oxy- the normal values for the hemoglobin concentration
genated blood would move past the tissues more ([Hb]) and the hematocrit (HCT).
quickly. Transit time through the systemic capillaries Table 3-14
would be quicker. The tissues would desaturate the he-
moglobin less, and the Sv̄O2 would likely remain Sex HCT [Hb]*
within the normal range.
Men 40%–54% 13.5–16.5 g/dl
(4:214), (3:270–272), (14:350), (16:327–328). Women 38%–47% 12.0–15.0 g/dl

IA2a *[Hb] can be expressed as g% or g/dl. The two units are synonymous.

3. B. Epiglottitis, caused by Hemophilus influenzae, type In response to hypoxemia, the red blood cell produc-
B, often is a respiratory emergency because it can re- tion increases as the body attempts to increase its
sult in complete supraglottic obstruction. This disease oxygen-carrying capacity. Chronic stimulation of the
has a predilection for occurring among children who bone marrow to increase erythrocyte production gen-
are younger than five. The clinical manifestations of erally occurs with certain congenital heart diseases,
epiglottitis include the following features: high-altitude exposure, and conditions associated with
chronic hypoxemia (e.g., chronic bronchitis and pul-
• labored breathing
monary fibrosis).
• fever
• a brassy, barking cough Despite the benefit of increasing the blood’s oxygen-
• a muffled voice carrying capacity, polycythemia imposes an increased
• leaning forward while sitting workload on the heart—especially the right ventricle,
• drooling because of the increased blood viscosity.
• cyanosis
(1:85, 332), (2:261), (4:63), (9:83, 84–86).
• thickened, rounded epiglottis (laternal neck X-ray),
or “thumb” sign
IA2f
Visual examination of the upper airway (i.e., direct 6. B. Echocardiography is a diagnostic procedure using
laryngoscopy) is generally discouraged because of the ultrasonic waves that bounce off the heart and its struc-
possibility of causing a complete obstruction. A lateral tures to enable the study of the heart’s anatomy and
neck radiograph, exhibiting a thickened, rounded motion. An echocardiogram generally shows the fol-
epiglottis (“thumb” sign) confirms the diagnosis. Once lowing cardiac structures and features:
the diagnosis of epiglottitis is confirmed, an artificial
airway must be inserted and antibiotic therapy must be • hypokinesis, or akinesis, of an ischemic myocar-
initiated. dium
• left or right ventricular hypertrophy
(1:162–163), (7:310), (16:597–598, 983–984), • regurgitant valves (aortic, pulmonic, mitral, or tricus-
(18:199–201). pid)
• stenotic valves (aortic, pulmonic, mitral, or tricuspid)
IA1h • ventricular thickness
4. B. During pregnancy, the measurement of the lecithin • atrial septal defects
(L)-sphingomyelin (S) ratio at approximately 34 weeks’
Many other cardiac structures and motions can be de-
gestation shows that the L/S ratio rises abruptly from
tected by echocardiography.
2:1. The more the ratio exceeds 2:1, the less likely this
child will experience pulmonary prematurity (and, (14:689, 714, 722).
therefore, the less likely the child will experience res-
piratory distress at birth). An L/S of 3:1 reflects stable IA1f(2)
pulmonary surfactant production and lung maturity. 7. C. Point B on the pressure-time waveform illustrated
Before 34 weeks’ gestation, the L/S ratio is normally in Figure 3-17 represents the PIP. Point C or D refers
less than 2:1. to the plateau or static pressure.
The L/S ratio is unreliable in diabetes and whenever The plateau pressure is the pressure-maintaining infla-
measurements are made from amniotic fluid contami- tion of the lungs during a period of no gas flow. An in-
nated with meconium or blood. spiratory hold or inspiratory pause enables the plateau
(1:1001), (16:926–927). (static) pressure measurements. This pressure represents

Chapter 3: Clinical Data 135

 the pressure overcoming the recoil tendency of the artery pressures to increase. The mean pulmonary artery
lungs. pressure might reach as high as 80 mm Hg.
By subtracting the plateau pressure from the PIP, the (9:313), (14:552–553).
pressure generated to overcome airway resistance
(PRaw) can be calculated. The following formula IA2a
demonstrates this calculation. 9. B. A chest radiograph is used to diagnose a pneumoth-
PIP - Pplateau = PRaw orax. Arterial blood-gas analysis will reflect nonspe-
cific abnormalities. Bronchoscopy is used to observe
For example, if the PIP was 35 cm H2O and the Pplateau the internal lumen of the airways; therefore, this mea-
was 20 cm H2O, the PRaw would be 15 cm H2O. For ex- sure is not appropriate. Peak flow measurement is used
ample, to quantify airway obstruction, such as bronchospasm.
35 cm H2O  20 cm H2O = 15 cm H2O (1:405, 408–410), (15:607–610).
This relationship facilitates the calculation of airway
resistance (Raw), effective static compliance (Cstatic), IA1h
and effective dynamic compliance (Cdyn). 10. C. The Apgar score obtained 1 minute after birth often
(10:147), (15:975), (16:646). reflects the degree of recovery following resuscitation
of a newborn infant. A 1-minute Apgar score of 7–10
indicates a stable newborn who requires routine
neonatal care (i.e., temperature maintenance, drying,
and airway clearance). A 1-minute score ranging from
Airway Pressure

4 to 6 indicates moderate depression and often requires

B an increased FIO2 via bag-mask ventilation. Infants
who are assigned 1-minute Apgar scores of 0 to 3 are
D
C severely depressed and demand endotracheal intuba-
tion and mechanical ventilation.
(1:1002–1003), (9:197–198), (16:922–923).
E
A
Time IA1d
Figure 3-17: Pressure-time waveform. (A) onset of inspira- 11. A. A person who is experiencing a diabetic coma is
tion, (B) peak inspiratory pressure, (C) plateau pressure, producing large amounts of ketone bodies, two of
(C–D) inflation hold, (D) end of inflation hold, and (E) end- which are acids (-hydroxybutyric acid and ace-
exhalation.
toacetic acid). The proliferation of these two acids
rapidly depletes the HCO 3̄ ion concentration in the
IA1g(2) blood and rapidly lowers the pH. Hyperventilation re-
8. D. Patients who have severe COPD characteristically sults in an attempt to reduce the acid component of the
have chronic hypoxemia, chronic hypercapnia, blood. Unfortunately, metabolic acids in this case
acidemia, and polycythemia. The chronic hypoxemia, (-hydroxybutyric acid and acetoacetic acid) are non-
chronic hypercapnia, and acidemia cause pulmonary volatile acids and can only be processed by the renal
vasoconstriction, which in turn produces diffuse pul- system. Carbonic acid (H2CO3) is a volatile acid that
monary vasoconstriction. At the same time, the can only be expelled from the body through the respi-
chronic hypoxemia causes erythropoietin to be re- ratory system. The elimination of volatile acid in the
leased from the kidneys to stimulate the production of presence of excess nonvolatile acid accumulation can-
more red blood cells. Essentially, the end result is not compensate fully for the primary metabolic prob-
polycythemia and increased blood viscosity. lem. Because the pH has not moved within the range
of 7.35 and 7.40 despite hyperventilation (PaCO2 10
What the right ventricle is faced with in this situation
torr), the pH is said to be partially compensated. If, in
is pumping blood with increased viscosity through
response hyperventilation returned, the pH to between
narrowed pulmonary vessels. The consequence is an
7.35 and 7.40, the description would then be fully or
increased right-ventricular workload. Eventually, the
completely compensated.
right ventricle hypertrophies and finally fails.
The interpretation of the arterial blood gas data pre-
The pulmonary vasoconstriction, which translates into
sented with this question is partially compensated
pulmonary hypertension, causes right heart hypertrophy
metabolic acidosis.
(along with increased blood viscosity). At the same time,
the pulmonary vasoconstriction causes the pulmonary (1:266–279), (4:251), (9:112–116), (16:149).

136 Chapter 3: Clinical Data

IA1f(5) IA2c
12. C. Capnography is a noninvasive method for the con- 15. C. Some pulmonary diseases respond favorably to the
tinuous measurement of end-tidal carbon dioxide ten- administration of a bronchodilator, usually a -2 ago-
sion (PETCO2) via infrared or mass spectrometry. The nist or an anticholinergic agent. Diseases often re-
benefit of measuring the PETCO2 is that under normal sponsive to bronchodilator therapy include asthma and
and stable cardiovascular conditions, it reflects the alve- COPD.
olar CO2 tension (and in turn, the arterial CO2 tension).
Asthmatics generally experience a beneficial response
The normal difference between the arterial PCO2 and
to -2 agonists such as metaproterenol (Alupent,
the PETCO2 is less than 3 mm Hg. This gradient widens
Metaprel), bitolterol (Tornalate), pirbuterol (Maxair),
as a result of the influence of a number of factors.
and salmeterol (Serevent). COPD patients, on the
For example, a low cardiac output causes less meta- other hand, often obtain relief from bronchospasm
bolically produced CO2 to be delivered to the pul- from the use of anticholinergic bronchodilators, i.e.,
monary circulation for gas exchange, thereby causing ipratropium bromide (Atrovent).
the arterial PCO2 to become much greater than the
The reason why COPD patients often derive benefit
PETCO2. Ventilation-perfusion (V̇A/Q̇ C) imbalances,
from anticholinergic bronchodilators is that these
likewise, produce an increased disparity between the
agents block vagally mediated bronchospasm, which
PaCO2 and the PETCO2. Similarly, an alveolar ventila-
appears to be the reason why COPD patients some-
tion out of phase with the level of carbon-dioxide pro-
times experience bronchospasm. Also, because anti-
duction widens the arterial PCO2-PETCO2 gradient.
cholinergic bronchodilators act slowly and have a
Some infants experience an increased arterial PCO2 as longer duration of effect, they are more often used as
a result of the added dead space of the CO2 sensor. maintenance drugs rather than for the relief of acute
Tachypneic infants might breathe too rapidly for an ac- dyspnea. Furthermore, inhaled anticholinergic bron-
curate measure to be made. chodilators can be administered concurrently with
other bronchodilators.
Aside from being independent of tissue perfusion and
displaying waveforms reflecting cardiopulmonary To assess a patient’s responsiveness to a bronchodila-
conditions, capnography is associated with a variety of tor, a before-and-after bronchodilator spirometry study
technical difficulties. is performed. The spirometric data obtained before the
bronchodilator is administered are used as the baseline
(1:363–368), (4:295–301), (6:146–148), (10:100–102),
to which the results from the post-bronchodilator test
(16:275, 313–314).
are compared. Generally, the change in the FEV1 is
used as the index reflecting the degree of effectiveness
IA1a of the bronchodilator. The percent change in the FEV1
is calculated according to the following reaction:
13. C. Progress notes are the portion of the patient’s chart
that discusses daily changes in the patient’s status.
% change in FEV1 =
According to Joint Commission on Accreditation of
Healthcare Organizations (JCAHO) standards, physi- post bronchodilator FEV1 – prebronchodilator FEV1
× 100%
cians are required to assess the effectiveness of therapy prebronchodilator FEV1
for the patient. The progress note section would con-
tain the latest physician comments on the status of the If the FEV1 improves by 15% or more, the assessment is that
patient and his responsiveness to therapy. the bronchodilator will help the patient.
(1:33–36). (6:49–50), (11:176), (20:151–152, 448).

IA1f(2)
IA1b 16. A. The minute ventilation (minute volume), or V̇ E, can
14. D. Four vital signs exist: (1) body temperature, (2) ven- be calculated by multiplying the tidal volume by the
tilatory rate, (3) heart rate, and (4) blood pressure. Vital respiratory rate (f). That is,
signs are not only evaluated during an initial patient ex-
amination but also during ensuing examinations and as VT × f = V̇ E
an assessment of therapeutic interventions. Sensorium 700 cc × 12 breaths/min. = 8,400 cc/min.
is not considered a vital sign; however, the patient’s
mental status is often reported in conjunction with the The other components of the V̇ E are the alveolar ventilation
vital signs. (V̇A) and the dead space ventilation (V̇ D). These two compo-
nents of the V̇ E are related as follows:
(1:302–305, 925), (9:35–46), (10:248–249), (16:161–163).

Chapter 3: Clinical Data 137

 V̇ E = V̇A + V̇ D A–B: removal of air from the anatomic dead space
B–C: combination of dead space air and alveolar air
Each can be similarly calculated as shown:
V̇A = alveolar volume  respiratory rate
60
V̇A = V̇A  f
50
D

mm Hg
and 40 C
V̇D = dead space volume  respiratory rate 30
V̇D = V̇D  f 20

(1:211–212), (7:588, 684), (9:130), (17:27–28). 10

A B E A
0
IA2c Time
17. D. Spirometry performed before and after bron- Figure 3-18: Normal capnogram.
chodilator therapy is a useful way to determine the
reversibility of lung dysfunction. Significant re- C–D: exhalation of alveolar air (alveolar plateau)
versibility is demonstrated by a greater than 15% to D: end-tidal CO2 value; PETCO2; end of exhalation
20% improvement in FEV1 following aerosolization of and beginning of inspiration
a bronchodilator. The following formula is used: D–E: inspiration of air remaining in ventilatory
circuit
(Postbronchodilator FEV1)–(Prebronchodilator FEV1) E–A: inspiration of air devoid of CO2
× 100
Prebronchodilator FEV1 Capnography is indicated for a variety of conditions
= % improvement and situations, including the following:
(1:465–466), (13:161–164). — monitoring the severity of pulmonary disease
— evaluating a patient’s response to therapy
IA2f — evaluating endotracheal intubation
18. A. The following signs and symptoms reflect a car- — assessing the efficacy of mechanical ventilatory
diac problem: support
— monitoring of the integrity of ventilator tubing and
• chest pain the artificial airway
• orthopnea—dyspnea in the reclining, or flat supine, — reflecting CO2 removal
position — assessing adequacy of pulmonary and coronary
• paroxysmal nocturnal dyspnea (PND)—recurrent blood flow
nightmares, and episodes of difficult breathing — monitoring inspired CO2 when CO2 gas is used
• night sweats therapeutically
• syncope—a brief lapse of consciousness caused by — evaluating the ventilator-patient system graphically
transient cerebral ischemia
• palpitations (AARC Clinical Practice Guidelines, Capnography/
• peripheral (pedal) edema Capnometry During Mechanical Ventilation),
• hypotension (1:363–366), (16:275, 313–314).
• diaphoresis
IA1g(1)
A electrocardiogram needs to be obtained immediately
20. A. All of the ECG findings listed are normal. Table
to evaluate the electrical activity of the heart.
3-15 outlines ECG measurements and the normal
(9:174), (16:862–865). range for each measurement.
Table 3-15
IA1f(5)
Measurement Normal Range
19. A. Capnography is the graphic display of inspired and
exhaled CO2 levels during breathing. Capnometry heart rate 60–100 bpm
refers to the numeric readings of CO2 levels obtained P-R interval 0.12–0.20 second
during breathing. Figure 13-18 illustrates a normal QRS interval  0.12 second
capnogram. ST segment isoelectric
T wave rounded and upright
A: beginning of exhalation
A–D: expiratory phase
(1:325–326), (9:184), (16:856).

138 Chapter 3: Clinical Data

IA2d matic excursion. The fact that the hemidiaphragms
21. A. No absolute indication exists for the insertion of a move only slightly in these patients makes it difficult
PAC. The need is determined by the physician, based to discern changes in the percussion note. In such
on the consideration of the patient’s condition. A PAC cases, radiography can ascertain diaphragmatic excur-
provides for the measurement of vascular pressures, sions more definitively.
flow rates, circulating volumes, and ventricular out- (1:308–309), (9:61–62), (16:171).
puts. Many clinical decisions are made based on the
data obtained from a PAC. IA1f(1)
(1:323, 1136), (4;209–210), (9:309), (14:254–255). 25. C. In the ICU, the MIP measurement should last at
least 20 seconds in order to assure maximum contrac-
IA1c tion of the diaphragm. The device used should incor-
22. D. Normal urine output ranges somewhere between 50 porate a one-way valve that enables exhalation but
and 60 ml/hr. Based on body weight, normal urine prevents inhalation. In this way, the maneuver is per-
output equals approximately 1 ml/kg/hr. Therefore, a formed at minimal lung volumes that would enable
70-kg person would likely excrete about 1,680 ml of maximum excursion of the diaphragm and chest wall
urine per day, i.e., 70 ml  24 hr = 1,680 ml/day. A during inspiratory efforts.
urine output of less than 20 ml/hr (less than 400 (1:825, 971, 1096), (7:68, 593), (9:257), (16:234–235,
ml/day) is called oliguria. Oliguria means diminished 630).
urine output in relation to fluid intake. The prefix
olig(o) means few, little, or scant. IA1f(2)
Oliguria indicates the presence of insufficient renal 26. A. The normal relationship between the static and dy-
perfusion, i.e., decreased blood volume (hypovolemia), namic compliance values or curves is illustrated in
or the onset of renal failure. When the urine output Figure 3-19.
exceeds 100 ml/hr, or 2,400 ml/day, the condition is
called polyuria. Failure to produce urine is described as
anuria. Static
Compliance
(9:96, 236), (10:300–301). Curve
Volume

IA1a Dynamic
23. C. According to the JCAHO, the physician’s order Compliance
Curve
should include the following: (1) type of treatment, (2)
frequency, (3) duration, (4) type and dose of medica-
tion, and (5) diluent and oxygen concentration. The
CRT should be aware of possible side effects of ther- Pressure
apy that he performs. Figure 3-19: Normal static and dynamic compliance curves.
(1:4–6, 16), (16:73–74, 94, 98). Mucous plugging causes an increase in airway resis-
tance. Therefore, the dynamic compliance will reflect
IA2a the fact that more pressure is necessary to cause a vol-
24. A. The degree of diaphragmatic excursion can be esti- ume change. Consequently, the dynamic compliance
mated by percussing the lower posterior thorax. The curve will move to the right, while the static compli-
CRT must have the patient inspire completely and ance curve remains normal. The plateau pressure, not
breath-hold. During the breath-hold, the CRT per- the PIP, is used in the calculation of the static compli-
cusses over the lower posterior thorax, moving down- ance. Because the plateau pressure (Pplateau) does not
ward and listening for changes in the percussion note. change in the presence of an increased airway resis-
The patient is then told to exhale to residual volume tance, the static compliance curve will remain normal.
and breath-hold once again as the CRT percusses in With the PIP increasing with each mechanical breath,
the same region to determine percussion-note changes. the dynamic compliance will decrease.
Diaphragmatic movement is sometimes difficult to de- The formulas for the calculation of these two mea-
termine via percussion in COPD patients, because surements are as follows:
these patients have varying degrees of hyperaeration.
VT
Patients who have severe COPD with extremely flat- Cstatic =
tened hemidiaphragms tend to have little diaphrag- Pplateau – PEEP

Chapter 3: Clinical Data 139

 VT IA1g(2)
Cdynamic =
PIP – PEEP 28. C. The PAC is a balloon-tipped, flow-directed catheter
inserted into the venous end of circulation (e.g., sub-
(1:937), (10:357–359). clavian vein). The distal tip of the PAC is meant to re-
side in the pulmonary artery just outside the right
IA1c ventricle. At times, the balloon is inflated. The balloon
27. A. White blood cells (leukocytes) play a significant role around the PAC tip obstructs blood flow around one of
in the body’s constant battle against infections. The nor- the pulmonary arterioles to produce a wedge pressure
mal total white blood cell (WBC) count ranges from reading. During normal physiologic conditions, when
4,500 to 11,500/mm3. When the WBC measurement is the mitral valve is open (ventricular diastole), the tip of
elevated, acute respiratory infections are likely present. the PAC can sense the pressure from the wedged posi-
tion all the way into the left ventricle. Figure 3-20 de-
Neutrophils, along with eosinophils, basophils, lym-
picts the PAC in the wedged position. Notice that the
phocytes, and monocytes, comprise the WBC popula-
mitral valve (between the left atrium and left ventricle)
tion. Table 3-16 lists each of these WBC types and
is open. Therefore, the PAC can record the pressure in
their average normal ranges.
the left ventricle at that time.
Table 3-16 When the mitral valve closes during ventricular systole,
WBC Type Normal Range the left ventricle is sealed off and cannot be sensed by
the catheter at that point.
neutrophils 1,800–7,500/mm3
eosinophils 0–600/mm3 The balloon of the PAC tip must not remain inflated
basophils 0–100/mm3 for more than 15 seconds. In other words, the wedged
lymphocytes 900–4,500/mm3 position must not be maintained for more than 15 sec-
monocytes 90–1,000/mm3 onds. Otherwise, ischemia can occur in the wedged
vessel distal to the inflated balloon tip.
Neutrophils, also called polymorphonuclear neutrophils (1:946–948), (2:196–197), (9:314), (14:273–274).
(PMNs), normally comprise 40% to 75% of the nor-
mal WBC population. Within this 40% to 75% range IA1f(4)
exist mature and immature neutrophils. Immature neu- 29. C. The dead space-tidal volume (VD/VT) ratio can be
trophils, called bands, range from 0% to 6%. calculated via the equation that follows:
Bacterial infections cause the neutrophil population to VD PaCO2  PĒCO2
rise (neutrophilia). Sometimes the infection is so severe =
that it causes the neutrophil population to rise rapidly VT PaCO2
and to increase in great numbers. Often, a rapid and The ratio represents the proportion of the tidal volume
great rise in neutrophils does not allow adequate time comprised of dead space volume. The greater the dead
for neutrophils to mature. Subsequently, the number of space volume (VD), the less the alveolar volume (VA)
immature neutrophils, i.e., bands, increases. Under such will be. Note the following relationship:
circumstances, the band population will exceed 6%.
VT = VD  VA
Some useful terms related to the WBC population are
listed here: From this relationship, you should be able to understand
that for a given VT, as the VD increases the VA decreases.
• leukocytosis: increased WBCs
• neutrophilia: increased neutrophils The tidal volume is comprised of a dead space volume
• leukopenia: decreased WBCs and an alveolar volume. When the dead space volume
• neutropenia: decreased neutrophils increases, the alveolar volume decreases if the tidal
volume remains constant.
(1:331–332), (2:86–87, 261), (9:83–86).

15
mm Hg

10

0
Figure 3-20: Pulmonary Capillary Wedge Pressure (PCWP) waveform.

140 Chapter 3: Clinical Data

 An increased dead space (VD) volume can be compen- who have chest wall deformities, patients who have
sated for in one of two ways. The overall VT can increase cervical spine fractions, and patients who are being
an attempt to increase the VA. Similarly, the respiratory considered for weaning from mechanical ventilation.
rate can increase to bring more volume of air into the
The normal MIP, measured from residual volume, is gen-
alveoli per time. Note the following relationship:
erally 60 cm H2O or less. The MEP, measured from to-
VT  f = (VD  f)  (VA  f) tal lung capacity, normally surpasses 80 to 100 cm H2O.
V̇E = V̇ D  V̇A Although body plethysmography would provide addi-
tional data regarding the patient’s mechanics of breath-
Pulmonary embolism will result in the obstruction of
ing, the procedure would likely be too taxing for a
pulmonary perfusion to certain regions of the lung, de-
neuromuscular disease patient. Although the test can
pending on where the embolism lodges in the pul-
be performed early on in the patient’s respiratory dis-
monary vasculature. Alveolar ventilation decreases as
tress, it would be difficult to perform body plethys-
the alveoli distal to the site of the pulmonary embolism
mography serially and accumulate data on such a
(obstruction) receive no perfusion. Those alveoli be-
patient over time. The MIP and MEP maneuvers re-
come alveolar dead space.
quire minimal equipment and patient participation and
Positive pressure mechanical ventilation increases the can be repeated much more frequently.
physiologic dead space by primarily causing a large
(1:825, 971), (2:259–260), (6:52–53), (9:257),
volume of gas to be inspired during each mechanical
(11:64–67), (16:234).
breath. In fact, the VD/VT ratio, which is normally
about 0.3, can increase as much as 50% during positive
pressure mechanical ventilation. Therefore, the VD/VT IA1f(2)
can increase to 0.6 in such situations. 32. A. Intermittent mandatory ventilation (IMV) is a venti-
latory mode enabling the patient to breathe sponta-
(1:211–212, 213), (4:73–76), (7:597–598, 688), neously between mandatory breaths delivered by the
(16:630), (17:137–39). ventilator. The mandatory breaths are controlled
mechanical-ventilation breaths. These controlled breaths
IA2d can be volume-controlled or pressure-controlled. The
30. C. A Central Venous Pressure (CVP) monitoring sys- spontaneous breaths are pressure-controlled with the pa-
tem will enable the administration of medications, fluid tient breathing from a continuous flow of gas or from a
infusion to maintain vascular volume, and provide ac- demand valve.
cess for obtaining mixed venous blood samples. Low
The flow-time, pressure-time, and volume-time curves
CVP values generally indicate low vascular volume
representing IMV are presented in Figure 3-21.
states or hypovolemia. High CVP measurements sug-
gest either hypervolemia or right ventricular failure. Figure 3-22 depicts the volume-time curve signifying
assist/control mode.
The normal values for CVP measurements range from
0 to 8 mm Hg or 3 to 11 cm H2O. Figure 3-23 represents the volume-time curve CPAP.
(1:190, 496), (4:209), (9:280, 303–309), (14:231), Figure 3-24 illustrates the volume-time waveform of con-
(16:323). tinuous mechanical ventilation with a PEEP of 5 cm H2O.
(1:863), (10:197–198), (15:958–959), (16:664–666).
IA2c
31. A. Both the maximum inspiratory pressure (MIP) and IA2e
maximum expiratory pressure (MEP) provide pul-
33. C. The body plethysmograph determines the thoracic
monary mechanics data. In particular, the MIP moni-
gas volume (VTG), airway resistance (Raw), and spe-
tors the status of the inspiratory muscles of ventilation,
cific airway conductance (SGaw). The Raw and SGaw
i.e., inspiratory muscle strength. The MEP, which is
measurements are often obtained to evaluate patient
the pressure generated during a maximum exhalation,
responsiveness to bronchodilators and to assess a pa-
reflects the status of the muscles of exhalation, includ-
tient’s response to bronchoprovocation studies.
ing the abdominal musculature. The MEP also repre-
sents the elastic recoil of the respiratory system. The Raw and SGaw derived from normal body
plethysmography tests are shown as follows.
Neuromuscular disease patients demand constant vig-
ilance in terms of their respiratory status (i.e., respira- Raw = 0.6 to 2.4 cm H2O/L/sec.
tory muscle strength, ability to cough, and protection
SGaw = 0.10 to 0.15 L/sec./cm H2O/L
of the airway). Other types of patients who often ben-
efit from MIP and MEP monitoring include patients (6:53–57), (11:54–58).

Chapter 3: Clinical Data 141

 Flow (lpm)

80

40

0
2 4 6 8 10 12 14 16 18 20
-40

-80

-120

Pressure (cmH2O)
60

40

20

0
2 4 6 8 10 12 14 16 18 20

Volume (cc)

1000
800
600
400
200
0
2 4 6 8 10 12 14 16 18 20 Time (seconds)

Figure 3-21: Flow-time, pressure-time, and volume-time waveforms reflecting IMV.

Volume (cc)

800
600
400
200
0
2 4 6 8 10 12 14 Time (seconds)

Figure 3-22: Volume-time waveform depicting assist/control ventilation.

IA2f the pressure waveform must be sufficient to overcome at-

34. A. High-frequency jet ventilation (HFJV) has the po- electasis, but it must not be so great as to exacerbate gas
tential to reduce barotrauma and can be useful in the trapping. Continuous monitoring of transcutaneous PO2
management of PIE. and PCO2 levels enable the rapid adjustment of ventilatory
settings to assure optimal ventilation and oxygenation.
Specification of ventilator settings is not yet a reality be-
cause of clinical limited experience with this type me- (1:353–356), (10:102–104), (11:261–263), (16:275,
chanical ventilator in the treatment of PIE. Amplitude of 314–315).

142 Chapter 3: Clinical Data

 Volume (cc)

300

200

100

0
2 4 6 8 10 12 14 16 18 Time (seconds)

Figure 3-23: Volume-time waveform representing CPAP.

Volume (cc)

800
600
400
200
0
2 4 6 8 10 12 14 Time (seconds)
Figure 3-24: Volume-time waveform reflecting continuous mechanical ventilation.

Table 3-17: Two categories of criteria for weaning. list of specific factors that can be assessed is included.
These criteria are best viewed as guidelines, because
Category 1: general criteria some patients who will fail certain criteria might still
— belief that the condition for which mechanical ventilation wean from the ventilator if the CRT is persistent and
was initiated has resolved supportive. In contrast, some patients who satisfy all of
— absence of septicemia the criteria sometimes fail to be weaned. In addition to
— hemodynamic stability reviewing the physiologic criteria listed in Table 3-17,
— secretions under control psychological encouragement must be given to the pa-
tient before, during, and after the process.
Category 2: specific criteria
Abbreviations: FIO2, fraction of inspired O2: P(A-a)O2,
— oxygenation/O2 transport alveolar-arterial partial pressure gradient; VC, vital ca-
— PaO2 greater than 60 mm Hg with FIO2 less than 0.40 on pacity; V̇E, minute ventilation; MVV, maximal voluntary
low-level PEEP
ventilation; MIP, maximum inspiratory pressure
— P(A-a)O2 less than 350 mm Hg
— cardiac index greater than 2.1 L/min/m2 (1:971–973), (7:652–653), (10:326–327), (16:630,
— no metabolic acidosis 1152).
Mechanics of Respiration IA1f(5)
— VC greater than 10 ml/kg ideal body weight 36. A. A pulse oximeter calculates percent oxygen satura-
— V̇ E(rest) less than 10 L/min. tion as the fraction of oxyhemoglobin divided by the
— MVV at least twice resting V̇ E amount of hemoglobin available to combine with oxy-
— patient-ventilator system compliance greater than 25 gen. Using two-wavelength spectrophotometry, a pulse
ml/cm H2O oximeter measures oxyhemoglobin and reduced hemo-
— MIP greater than 30 cm H2O globin but not carboxyhemoglobin or methemoglobin.
The percent oxyhemoglobin calculated by a pulse
oximeter will be falsely high if the patient has been ex-
IA1f(1) posed to carbon monoxide. The absorption wavelength
35. B. The decision to wean a patient from mechanical of carboxyhemoglobin is similar to oxyhemoglobin.
ventilation is often fraught with uncertainty. No ab- Therefore, the oximeter detects carboxyhemoglobin as
solute criteria identify whether an attempt at weaning oxyhemoglobin. When a patient breathes oxygen, the
will be successful or not. A number of assessments can percent oxyhemoglobin (SpO2) will likely be elevated,
be made assisting in making the decision, however. A but the performance of the pulse oximeter is unaffected.

Chapter 3: Clinical Data 143

 The pulse oximeter must detect a peripheral pulse in or- 4) arterial blood gas analysis
der to distinguish between systole for arterial blood and 5) sputum gram stain/culture, acid-fast stain/
diastole for venous blood. Shivering or any constant culture for mycobacteria, KOH exam and fun-
motion artifact might be detected by a pulse oximeter gal culture, P carinii stain, Legionella sp. anti-
as pulses; consequently, motion causes a pulse oxime- body stain
ter to read falsely low. 6) blood cultures
7) pleural fluid analysis
(1:359–362), (6:144–146), (4:281, 286–291),
(9:267–268). (1:432–433), (9:81–84, 87, 88, 90–92, 94–96).

IA1g(1) IA2d
37. A. The point of maximal impulse (PMI) is the area 40. B. A pulse oximeter is a useful device for monitoring
where the systolic pulse is felt and visualized. The a patient’s oxygenation status. This device has distinct
PMI is normally on the left near the midclavicular line limitations, however. At oxygen saturations of 80% to
at the fifth intercostal space. Shift of the PMI suggests 100%, the accuracy of pulse oximetry is about ±2.0%.
mediastinal shift associated with pneumothorax or lo- In other words, at SpO2 readings between 80% and
bar atelectasis. The PMI is often difficult to locate on 100%, the reading will be ±2.0% of the actual SaO2.
pulmonary emphysema patients, because the hyperin- The accuracy of a pulse oximeter relates to the oxyhe-
flation interferes with the transmission of the systolic moglobin dissociation curve. Therefore, because of the
vibrations. In some emphysema cases, the PMI can be sigmoid shape of the oxyhemoglobin dissociation
identified in the epigastric area. curve, a pulse oximeter is inadequate for monitoring
The palpation of anterior movement of the sternum hyperoxemia. For example, an SpO2 reading of 100%
during systole in the presence of right-ventricular hy- might mean a PaO2 of 100 torr or a PaO2 greater than
pertrophy is described as substernal heave. 100 torr (e.g., 230 torr). When the SpO2 reaches 100%,
a pulse oximeter is not a useful predictor of the PaO2.
(1:315), (9:68).
On the lower end of the range, a pulse oximeter is sim-
ilarly inadequate for predicting the corresponding
IA2a
PaO2. For example, an SpO2 value less than 80% can-
38. C. Characteristic X-ray findings associated with not accurately predict the corresponding PaO2.
COPD include lowered or flattened diaphragms, hy-
perlucency, increased anteroposterior (AP) diameter, In the case of the infant in this question, an arterial
increased retrosternal airspace, and leveling of the ribs blood gas sample would provide the precise PaO2. Hy-
(horizontal ribs). These changes result from a loss of peroxemia in neonates can cause retinopathy of prema-
elastic lung tissue, which in turn produces a decreased turity (ROP). ROP can result from sustained high PaO2
density. The decreased density leads to the hyperlu- levels (greater than 100 torr). High PaO2 levels in a
cency. Air trapping, which increases the AP diameter, neonate’s blood can cause vasoconstriction of retinal ar-
pushes the hemidiaphragms down and causes the ribs teries. This condition can ultimately lead to blindness.
to lose their “bucket handle” slant (i.e., horizontal rib (1:362–363, 928), (4:183, 284), (6:144–145),
angles form). (9:267–268), (16:310–312, 377).
Increased opacity is associated with consolidation,
fluid, or any other pathology that causes increased IA2c
density. The decreased density leads to the hyperlu- 41. C. The maximum voluntary ventilation maneuver
cency. The right hemidiaphragm is normally elevated evaluates the status of the compliance of the lung-chest
about 2 cm above the left because of the position of the wall system and the airway resistance. Overall, this
liver. maneuver assesses the mechanical properties of the
(15:214), (16:1027). respiratory system as well as the muscles of respira-
tion. The MVV is commonly performed before a sub-
IA1c ject undergoes exercise testing. MVV results are then
compared with exercise ventilation.
39. B. An adult patient who is about to be hospitalized for
a suspected community-acquired pneumonia should (1:386–387), (6:47–49), (9:135), (11:51–54), (16:235).
receive the following tests:
1) chest radiography IA1b
2) complete blood count (CBC) 42. A. The normal ranges for arterial blood gas and acid-
3) blood chemistries (glucose, BUN, serum Na) base measurements are listed as follows:

144 Chapter 3: Clinical Data

 • arterial oxygen tension: 80 to 100 mm Hg (AARC Clinical Practice Guidelines for Arterial Blood
• arterial carbon dioxide tension: 35 to 45 mm Hg Analysis, Respiratory Care, 38–505–510, 1993),
• oxyhemoglobin saturation: 95% to 98% (1:343), (9:105–108), (16:175, 260).
• arterial pH: 7.35 to 7.45
• bicarbonate: 22 to 26 mEq/liter IA1f(2)
(1:1144), (9:105), (16:260). 46. B. The normal I:E ratio for a spontaneously breathing
adult is 1:1 to 1:2. Exhalation should normally be about
IA1g(2) equal to or twice as long as inspiration. Patients who ex-
perience a decreased lung compliance, e.g., atelectasis,
43. C. The CVP value can be measured by using a single
often assume rapid, shallow breathing. Obstructive lung
lumen catheter or via the proximal port of a pulmonary
disease patients (i.e., chronic bronchitics and patients
artery (Swan-Ganz) catheter, which is a multi-lumen
who have pulmonary emphysema) demonstrate de-
catheter. To measure the CVP, the catheter’s tip must
creased I:E ratios. These ratios can range from 1:3 or
be positioned in the superior vena cava. The central ve-
less, (i.e., 1:4, 1:5, etc.).
nous catheter measures the pressure in the vena cava.
As more venous blood returns to the right side of the (1:307–308), (7:164), (9:57).
heart, the CVP value increases. Conversely, as venous
return to the right heart decreases, CVP pressure de- IA1h
creases. 47. C. Normally, the transcutaneous PO2 (PtcO2) and the
The CVP value often indicates the vascular volume arterial Po2 (PaO2) exhibit excellent correlations. The
status (i.e., hypovolemia or hypervolemia). A low CVP fact that these two measurements correlate well does
value generally reflects hypovolemia; an increased not mean that they will be equal, however. The capa-
CVP measurement suggests either hypervolemia or bility of trending is an important aspect associated
right ventricular failure. with these measurements. The PtcO2 and PaO2 corre-
late best within the normal range of arterial oxygen
The CVP can be measured by using a calibrated water tensions.
manometer or a transducer-monitoring system. When
a calibrated water manometer is used, the normal CVP A number of physiologic factors influence the degree
range is 3 to 11 cm H2O. Measurements obtained from of correlations between the PtcO2 and the PaO2. These
the transducer-monitoring system ranges from 0 to 8 factors include cardiac output and body temperature.
mm Hg. As the cardiac output falls, the PtcO2 decreases—
although the PaO2 may remain normal. Skin perfusion
A CVP measurement of 15 mm Hg is greater than nor- is related to the temperature. For example, when the
mal. Therefore, either right ventricular failure or fluid skin perfusion is low, less power is required to main-
overload is suspected. Volume overload can usually be tain the electrode temperature. Conversely, as skin per-
effectively treated with diuretics. fusion increases, more power is needed to maintain the
(1:946), (14:231–234). electrode temperature.
A patent ductus arteriosus (PDA) influences the corre-
IA2d lation between the PtcO2 and the PaO2 from a UAC.
44. B. Transcutaneous CO2 monitors are useful for evaluat- Preductal blood, which reflects the partial pressure of
ing trends in patients receiving mechanical ventilation. oxygen before the PDA, displays higher values than
They might, however, overestimate or underestimate the postductal blood, reflecting blood PO2 after the PDA.
arterial PCO2. Arterial blood sampling for direct deter- Therefore, a transcutaneous electrode placed in the
mination of the arterial PCO2 and pH is essential for ac- right upper chest will display the PO2 of preductal
curate evaluation of acid-base status. blood, while blood drawn from a UAC will reflect
postductal PO2. When right-to-left shunting is present,
(1:353–356), (10:102–104), (11:261–263), (16:275,
portions of blood leaving the right ventricle (venous
314–315).
blood) via the pulmonary artery will flow through the
PDA into the arterialized blood in the aorta. Blood
IA1d leaving the left ventricle and branching off the aorta
45. A. Arterial blood gas analysis should be performed before the PDA, specifically the brachiocephalic, left
only when clinically indicated to assess respiratory subclavian, and left common carotid arteries, will be
function. This analysis is indicated when the patient’s unaffected by the shunt. This blood constitutes the pre-
symptoms, history, or physical examination suggest ductal blood. The left-ventricular output that flows
significant acid-base, ventilation, or oxygenation de- past the PDA will mix with venous blood. This blood
rangement. mixture is the postductal blood.

Chapter 3: Clinical Data 145

 Therefore, in the presence of a PDA, a transcutaneous breath sounds as air moves in and out of the respiratory
electrode placed in the right upper quadrant of the tract. Vibration is a part of the chest physiotherapy reg-
chest will display PO2s higher than blood drawn from imen to help promote bronchial hygiene.
a UAC.
(1:306–315), (16:163–176).
(1:1034), (16:940–941).
IA1a
IA1c 50. B. The patient’s chart is a legal document consisting of
48. A. A routine urinalysis typically contains information numerous sections, such as (1) admissions records, (2)
concerning the following characteristics of a urine medication records, (3) a laboratory sheet, and (4)
sample: physician’s orders. The section for physician’s orders
contains documentation for all medications, treat-
• appearance
ments, and diagnostic therapeutic procedures.
— color
— cloudy/clear (1:33), (16: 44–45, Tables 2-11, and 2-12).
• protein
— proteinuria IA1g(2)
• blood 51. B. The pulmonary capillary wedge pressure (PCWP)
— hematuria provides information about the left atrium in terms of
• specific gravity the mean left atrial pressure when the mitral valve is
— increased concentration: dehydration closed. While the mitral valve is opened, the PCWP in-
— increased dilution: high fluid intake dicates left ventricular preload by measuring the
• pH LVEDP. The LVEDP represents an estimate of the
— acid-base status LVEDV. The LVEDV is the actual preload. Because
• glucose the volume in the left ventricle just prior to systole,
— glucosuria: diabetes or certain renal diseases i.e., end-diastole, is not easily determined, the LVEDP
• ketones is used to reflect the LVEDV.
— ketosis
— associated with starvation and diabetes mellitus Because the LVEDP is affected by the compliance of
• bilirubin the left ventricle, the more stiff the ventricular wall
— obstruction of outflow of bile from liver (decreased ventricular compliance), the higher the
• urobilinogen pressure caused by the volume in that chamber. There-
— liver disease/hemolytic state fore, when the ventricular compliance decreases (e.g.,
• nitrates myocardial ischemia and ventricular hypertrophy), the
— bacteria LVEDP overestimates the LVEDV. In other words,
• urinary sediment when ventricular compliance decreases, the LVEDP
— blood cells overestimates the preload.
— casts Conversely, if the ventricular compliance increases,
— crystals more blood volume can occupy that chamber for a
(4:250–252), (9:96). given amount of pressure. Therefore, when ventricular
compliance increases, the LVEDP underestimates the
IA1b LVEDV, and the LVEDP underestimates the preload.
49. A. Chest physical assessment includes the following The three compliance curves in Figure 3-25 illustrate
procedures: (1) inspection, (2) palpation, (3) percussion, this point.
and (4) auscultation. Inspection affords the clinician the
When ventricular compliance is decreased, the volume
opportunity to observe any changes in the normal con-
(V1) will be less at pressure (P), than the volume (V3),
tour of the thorax, e.g., kyphosis and barrel chest. Other
at the same pressure (P) when the compliance in-
aspects noted during inspection are patient position,
creases. The V2-P curve represents the volume-pressure
ventilatory pattern, and accessory muscle usage.
relationship when ventricular compliance is normal.
Palpation is a means of assessing chest movement, ex-
Again, when the PCWP is used as a measure of the
pansion, and symmetry by placement of the exam-
LVEDP in the presence of a stiff left ventricle, it will
iner’s hands on the patient’s thorax. Percussion allows
overestimate the LVEDV (i.e., the left ventricular pre-
for the assessment of the lungs via the quality of sound
load).
transmission through the thorax. The sound is pro-
duced by the examiner’s fingers. Auscultation provides (1:946–948), (2:196–197), (9:312–314, 322),
the means of assessing via a stethoscope the nature of (16: 322–324).

146 Chapter 3: Clinical Data

 (1) (2) (3) nected to the exhalation port of a breathing circuit and can
capture the exhaled gas.
P
(1:211–213), (2:188–191), (4:75–76), (14:258–259),

d
Pressure

d
Decrease

l
rma

se
(17:21–22, 115).

rea
No

In c
IA1d
54. D. At the alveolar-capillary membrane level, oxygen
molecules passively diffuse into the pulmonary capil-
0 lary blood because of a partial pressure gradient for
V1 V2 V3
oxygen between the alveoli and pulmonary capillary
Volume blood.
Figure 3-25: Three cardiac compliance curves. (1) de- Normally, the alveolar PO2 is about 100 torr, and the
creased ventricular compliance causing low volume (V1) at mixed venous blood PO2 is approximately 40 torr.
P; (2) normal ventricular compliance associated with normal
volume (V2) at P; and (3) increased ventricular compliance Therefore, the normal gradient while a person breathes
resulting in increased volume (V3) at P. room air (FIO2 0.21) is calculated:
PAO2 – Pv̄O2 = Po2 gradient across the A/C
IA2c membrane
52. B. According to the AARC Clinical Practice Guide-
lines for Body Plethysmography, when a patient is un- 100 torr – 40 torr = 60 torr
able to perform multibreath breath tests (e.g., The alveolar PO2 is calculated using the alveolar air
spirometry), body plethysmography is indicated. Body equation. That is,
plethysmography enables the measurement of lung
volumes to help differentiate between obstructive and PAO2 = FIO2(PB – PH2O) – PaCO2 FIO2 + ( 1– FIO2
R )
restrictive diseases. Furthermore, this procedure mea-
sures the Raw and SGaw, both of which are useful in At sea level, while breathing room air (FIO2 0.21) and
assessing patient responsiveness to a bronchodilator or having a normal respiratory quotient (R = 0.8), the
following a bronchial provocation test. PAO2 is calculated as follows:
Again, if a patient is unwilling or incapable of per- PAO2 = 0.21 (760 torr – 47 torr) –40 torr
forming an FVC maneuver, body plethysmography is
recommended. ( 0.21 +
0.8 )
1– 0.21

(AARC Clinical Practice Guidelines for Body Plethys- = 0.21 (713 torr) – 40 torr (1.2)
mography, Respiratory Care, 39:1184–1190, 1994),
(1:381), (6:79–82), (11:130–134). = 150 torr – 48 torr
= 100 torr
IA1f(4)
Let’s apply the FIO2 given in this question to the alve-
53. A. The VD/VT ratio is calculated via the Enghoff mod-
olar air equation, in order to calculate this patient’s ex-
ification of the Bohr equation. This equation is shown
pected PAO2.
as follows.
PAO2 = 0.28 (760 torr – 47 torr) – 40 torr
VD PaCO2  PĒ CO2
VT
=
PaCO2 ( 0.21 +
0.8 )
1– 0.21

In its purest form, this equation involves using the = 0.28 (713 torr) – 40 torr (1.18)
PACO2 instead of the PaCO2. Because CO2 equilibrates
completely across the alveolar-capillary membrane, = 200 torr – 47 torr
however, and because the PACO2 and PaCO2 are ap- = 153 torr
proximately equal, the PaCO2 can substitute for the
PACO2. This patient’s PAO2 is expected to be about 153 mm
Hg. Based on this calculation, there is no way possible
An arterial blood gas provides quick access to the PaCO2 that the reported PaO2 of 225 mm Hg can be accurate.
measurement. The PĒ CO2, on the other hand, requires the A PAO2 of 153 mm Hg cannot produce a PaO2 of 225
collection of the patient’s complete exhaled tidal volume. mm Hg. Therefore, reason dictates that an analytical
This collection is generally accomplished by collecting error has occurred. The PO2 electrode of the blood-gas
the patient’s expirate in a Douglas bag. This bag is con- analyzer must be checked.

Chapter 3: Clinical Data 147

 If air bubbles contaminated this arterial blood sample, The “H” represents height, and the “A” refers to age.
assuming dry atmospheric gas, the maximum PAO2
Despite racial differences in lung functions, a racial-
would be
correction factor is not applicable to all pulmonary func-
PO2 = 0.21 (760 mm Hg) tion measurements. Some cardiopulmonary labs reduce
measured lung volumes by 10%–15% for Blacks. Cur-
= 160 mm Hg
rently, no separate regression equations obtained from
Therefore, air bubbles in the blood sample would not healthy subjects of different races are available.
account for a PaO2 value of 225 mm Hg. Furthermore,
(6:29, 332), (11:480 Appendix E).
room air has a PCO2 of essentially 0 mm Hg. Air bub-
bles in the blood sample would cause the PCO2 of the IA1g(2)
blood to be significantly low and would result in an in-
creased blood pH. Hyperventilation is not a correct 57. B. The CO2 (end-pulmonary capillary total oxygen
choice, because the PaCO2 and pH are within their nor- content) is calculated by using the arterial hemoglobin
mal ranges. If hyperventilation were present, the concentration and by assuming that the PO2 (end-
PaCO2 would have decreased, and the pH would have pulmonary capillary partial pressure of oxygen) is equal
increased. A PaO2 of 225 mm Hg could constitute over- to the partial pressure of oxygen in the alveoli (PAO2).
correction of hypoxemia, but not in this situation— The alveolar air equation is used to calculate the PAO2:
because the PaO2 value of 225 mm Hg is unachievable ALVEOLAR AIR EQUATION
under these circumstances. The previous discussion
and calculation demonstrate that the maximum PAO2
PAO2 = FIO2(PB – PH2O) –PaCO2 FIO2 + ( 1– FIO2
R )
would be 153 mm Hg.
The shunt fraction (Q̇ S/Q̇ T) is calculated from the
(3:311, 367), (7:665), (16:251, 269). shunt equation that follows.
SHUNT EQUATION
IA1b
Q̇ S CćO2  CaO2
55. C. The normal ranges for the vital signs of resting =
adults are as follows: Q̇ T CćO2  Cv̄O2

• heart rate: 60 to 100 bpm (3:98), (4:169), (7:692–694), (16:329).

• ventilatory rate: 10 to 20 breaths/min.
• temperature: 37ºC ± 0.5ºC IA2c
• systolic blood pressure: 95 to 140 mm Hg 58. A. Three procedures are available for measuring the
• diastolic blood pressure: 60 to 90 mm Hg functional residual capacity (FRC): (1) the closed-
circuit helium dilution, (2) the open-circuit nitrogen
(1:302–305, 925), (9:35–46), (10:248–249),
washout, and (3) body plethysmography.
(16:161–-163).
The most accurate of these three procedures is body
IA1f(1) plethysmography. Because the subject sits inside the
body plethysmograph, the entire volume of gas inside
56. C. The predicted normal FEV1 for any subject is based the lungs is measured. In the case of both the closed-
on the following four factors: (1) gender, (2) age, (3) circuit helium dilution technique and the open-circuit
height, and (4) race. These factors are described as an- N2 washout tests, areas of the lung that are poorly
thropometric measurements. ventilated might not be completely measured. This sit-
The Morris equations for predicting the FEV1 are as uation is particularly significant in pulmonary emphy-
follows: sema and chronic bronchitis, i.e., COPD in general.
Both of these conditions are characterized by air-
MORRIS EQUATIONS FOR FEV1 trapping and hyperinflation.
males: FEV1 (L) = 0.092(H) – 0.032A – 1.260 (1:376–380), (6:79–82), (9:131–134), (11:482 Appen-
females: FEV1 (L) = 0.089(H) – 0.024A – 1.93 dix E), (16:236–238).

The Knudson equations for the predicted FEV1 are IA1f(2)

shown. 59. D. An MIP of approximately –20 cm H2O is ordinarily
KNUDSON EQUATIONS FOR FEV1 sufficient to produce a vital capacity of about 15 ml/kg
of ideal body weight.
males: FEV1 (L) = 0.052(H) – 0.027(A) – 4.203
(1:825, 971, 1096), (7:68, 593), (9:257), (10:179–180),
females: FEV1 (L) = 0.027(H) – 0.021(A) – 0.794 (15:1021–1022), (16:234–235, 630).

148 Chapter 3: Clinical Data

IA1f(4) (AARC Clinical Practice Guidelines for Bronchial Provoca-
60. A. The guideline for determining the approximate tion, Respiratory Care, 37:902–906, 1992), (6:205–212),
amount of anatomic dead space that a person has is 1 cc (11:312–318), (16:232).
of anatomic dead space per pound of ideal body weight.
Note that the guideline indicates ideal body weight. IA1f(5)
Therefore, regarding patients who are obese, the ideal 63. A. During a procedure such as a bronchoscopy, the
body weight needs to be obtained from a nomogram. most appropriate method of monitoring patient oxy-
genation is pulse oximetry. Frequent arterial blood
For the problem presented here, the patient’s ideal
sampling throughout the course of a bronchoscopic
body weight was given as 75 kg. Consequently, the
procedure would be impractical. Similarly, the use of a
unit kilogram needs to be converted to pounds.
transcutaneous oxygen monitor generally requires an
75 kg  2.2 lbs/kg = 165 pounds occasional arterial blood gas sample to determine the
degree of correlation between the PtcO2 and the PaO2.
Based on the aforementioned guideline, this person
Co-oximetry would also involve the frequent sampling
would have an anatomic dead space of approximately
of arterial blood to determine the degree of oxygen sat-
165 cc.
uration. Pulse oximetry provides a reliable, noninva-
The following formulas can also be used to determine sive means of monitoring oxygen saturation. If the
a person’s approximate ideal body weight (IBW) in SpO2 falls below 80%, however, an arterial blood gas
pounds. should be obtained—because pulse oximetry readings
below 80% are considered inaccurate.
males: lbs (IBW) =
106  [6  (height in inches – 60)] From a clinical standpoint, however, the CRT would
stop the bronchoscopy and administer oxygen to the
females: lbs (IBW) =
patient, rather than wait for an arterial blood gas sam-
105  [5  (height in inches – 60)]
ple. The patient’s oxygenation status would be ad-
(15:309, 489). dressed immediately.
(AARC Clinical Practice Guidelines for Pulse
IA1f(3) Oximetry, Respiratory Care, 36:1406–1409, 1991),
61. A. Compliance is defined as volume change divided by (1:359–362), (4:281, 286–291), (6:144–146),
pressure change, i.e., V/P. The units for compliance (9:267–268), (11:229–232).
are liter/cm H2O. Resistance or Raw (cm H2O/liter/sec.)
refers to opposition to ventilation by the airways, tissues, IA2e
and other factors. Conductance (liters/sec./cm H2O) is the
64. A. A pre-operative assessment of the peak expiratory
reciprocal of resistance. An example of conductance
flow rate (PEFR) provides a baseline to which post-
(Gaw) is the carbon monoxide diffusing capacity (DLCO).
operative measurements could be compared. Pre-
Impedance describes total resistance to ventilation.
operatively, the measurement should not be biased by
(1:211, 969), (9:137–138), (16:129, 245–246). factors that would alter the baseline value. Using an in-
haled bronchodilator would bias the baseline by re-
IA2c ducing bronchospasm; smoking a cigarette would bias
62. C. According to the AARC Clinical Practice Guide- the baseline by increasing airway edema and airflow
lines for Bronchial Provocation, patients who receive resistance. Ingesting a large meal might interfere with
anticholinergic medications must refrain from using inhaling maximally, because the PEFR should be mea-
this type of drug 12 hours before the bronchoprovoca- sured after the patient has inspired maximally. Having
tion. Table 3-18 lists the time for withholding certain the patient perform the preoperative assessment near
drugs before bronchial provocation. the time the chest X-ray was taken might provide for a
correlation between these two diagnostic procedures.
Table 3-18
(6:45–47), (9:134–135), (11:15–16), (16:229).
Abstinence Time Before
Drug Bronchial Provocation IA2d
aerosolized anticholinergics 12 hours 65. D. Two general indications for an arterial line insertion
aerosolized 2-agonists 12 hours are as follows:
disodium cromolyn glycate 8 hours • continuous arterial pressure monitoring
oral 2-agonists 12 hours
• serial arterial blood gas measurements
theophylline 48 hours
H1 receptor antagonists 48 hours Within these two general categories of indications are
antihistamines 72–96 hours specific situations where arterial cannulation is needed:

Chapter 3: Clinical Data 149

 • patients who are being maintained on mechanical smoke. This resident COHb level causes CO back
ventilators pressure during the diffusing capacity procedure.
• patients who are being weaned from mechanical Clinically, a 1.0% decrease in the CO diffusing capac-
ventilation ity (DLCO) occurs for every 1.0% increase in COHb
• patients who are hemodynamically unstable blood levels. If a smoker smokes a cigarette an hour or
• patients who are in ventilatory failure less before performing a DLCO study, the DLCO value
• patients who are receiving potent vasodilators or will be adversely influenced by the contents of the cig-
vasopressors arette smoke. According to the AARC Clinical Prac-
tice Guidelines, a person must refrain from smoking at
The actual decision of inserting an arterial line de-
least 24 hours before the test.
pends on how severely ill the patient is.
(AARC Clinical Practice Guidelines for the Single
(3:306–307), (4:16–17), (14:190).
Breath Carbon Monoxide Diffusing Capacity Respiratory
Care, 38:511–515, 1993), (1:386–390), (6:111–121),
IA1g(2) (9:137), (11:126–149), (16:240–242).
66. A. An elevated intrathoracic pressure causes an in-
creased CVP reading. The CVP reading will decrease IA1f(2)
during spontaneous inspiration and will increase with
68. C. The flow-time, pressure-time, and volume-time
a positive pressure mechanical breath. When a pa-
waveforms during pressure support ventilation (PSV)
tient’s own effort initiates a mechanical breath, the
are shown in Figure 3-26.
CVP reading falls and then immediately increases be-
yond the baseline as the mechanical (positive pressure) Each breath in the PSV mode is patient triggered or
breath is delivered. The CVP value rises during a me- initiated. Each inspiration is augmented with a preset
chanical breath, because high intrathoracic pressures pressure. The patient establishes the respiratory rate
surround the heart and the major blood vessels. (f), the inspiratory flow (V̇ I), and the inspiratory time
(TI). The tidal volume is determined by the lung com-
The positive pressure transmitted from the patient’s
pliance, airway resistance, and the pressure (preset
airways to the cardiovascular structures causes diffi-
pressure minus PEEP).
culty reading and interpreting CVP measurements.
This situation is aggravated if the patient is receiving SIMV with PSV waveforms are depicted in Figure 3-27.
PEEP or CPAP. Patients who are receiving PEEP must
The flow-time, pressure-time, and volume-time curves
not be removed from the PEEP when a CVP reading is
representing pressure control inverse ratio ventilation
being attempted. For patients who are cooperative,
(PCIRV) follow in Figure 3-28.
however, responsive mechanical ventilation can be in-
terrupted for a few cardiac cycles to enable the CVP to The flow-time, pressure-time, and volume-time wave-
be read without a mechanical ventilation artifact. forms associated with pressure control ventilation
(PCV) are illustrated in Figure 3-29.
Similarly, if the patient is not receiving PEEP but is still
being mechanically ventilated, the ventilator can be (1:864, 877), (10:199), (15:960), (16:667–668).
disconnected for a few cardiac cycles while the CVP is
measured. When PEEP is being given, the CVP should IA1f(4)
be read at end-exhalation. Sometimes, CVP readings 69. B. The formula for calculating the dead space fraction
during mechanical ventilation are not easily obtained. (VD/VT) follows:
In those cases, patient evaluation and management are
based on analyzing the CVP waveform trend. VD PaCO2  PĒ CO2
=
(9:307–308), (14:235–237). VT PaCO2
where,
IA2c
67. D. The diffusing capacity of the alveolar-capillary
membrane is measured by using about 0.3% carbon
monoxide (CO). What makes CO useful for this pur-
VD = dead space volume (ml)
VT = tidal volume (ml) } VD is the dead
space
VT fraction

pose is the negligible level of CO normally present in

PĒ CO2 = mean exhaled PCO2 (torr) fraction
the blood—and hemoglobin’s avid affinity for CO (ap-
proximately 240 times that for O2). People who smoke PaCO2 = partial pressure of CO2 in arterial
accumulate levels of carboxyhemoglobin (COHb) in blood (torr)
their blood. In fact, smokers can have COHb levels as
The calculation is as follows:
high as 10% or more, depending on how much they

150 Chapter 3: Clinical Data

 Flow (lpm)
80
60
40
20
0
-20 2 4 6 8 10 12 14
-40
-60
-80

Pressure (cmH2O)
30

20

10

0
2 4 6 8 10 12 14

Volume (cc)
800
600
400
200
0
2 4 6 8 10 12 14 Time (seconds)

Figure 3-26: Flow-time, pressure-time, and volume-time waveforms

representing PSV.

Flow (lpm)
80

40

0
2 4 6 8 10 12 14 16 18 20
-40

-80

Pressure (cmH2O)

30

20

10

0
2 4 6 8 10 12 14 16 18 20

Volume (cc)

800

600

400

200

0
2 4 6 8 10 12 14 16 18 20 Time (seconds)

Figure 3-27: Flow-time, pressure-time, and volume-time waveforms characterizing SIMV with PSV.

Chapter 3: Clinical Data 151

 Flow (lpm)
80

40

0
2 4 6 8 10 12 14 16 18
-40

-80

Pressure (cmH2O)
40

30

20

10

0
2 4 6 8 10 12 14 16 18

Volume (cc)

1000
800
600
400
200
0
2 4 6 8 10 12 14 16 18 Time (seconds)

Figure 3-28: Flow-time, pressure-time, and volume-time waveforms reflecting PCIRV.

Flow (lpm)
80

40

0
2 4 6 8 10 12 14 16 18
-40

-80

Pressure (cmH2O)
40

30

20

10

0
2 4 6 8 10 12 14 16 18

Volume (cc)

1000
800
600
400
200
0
2 4 6 8 10 12 14 16 18 Time (seconds)

Figure 3-29: Flow-time, pressure-time, and volume-time waveforms representing PCV.

152 Chapter 3: Clinical Data

 VD 49 torr – 32 torr Inserting the known values,
=
VT 49 torr 250 ml O2/min
C(a  v̄)O2 =
= 0.35 (5 L blood/min.)(1,000 ml blood/L blood)
(1:211–213), (6:98–99), (9:258–259), (16:330). 250 ml O2/min.
=
5,000 ml blood/min.
IA1b
70. B. Dyspnea associated with sitting or standing is = 0.05 ml O2 /ml blood
called platypnea. Platypnea is a frequent complaint of = (0.05 ml O2 /ml blood)(100)
chronic bronchitics and patients who have had a pneu-
monectomy. Speculation is that this form of dyspnea = 5.0 ml O2 /100 ml blood, or 5 vol%
occurs when these patients experience postural (1:225–226), (9:290), (17:135).
changes. These postural changes produce ventilation-
perfusion (V̇A/V̇C) alterations, momentarily affecting IA1c
gas exchange.
72. D. The normal white blood cell (leukocyte) count
Orthopnea is also a form of dyspnea and occurs in con- ranges from 4,500 to 10,000/mm3 of blood. An ele-
junction with congestive heart failure and manifests it- vated white blood cell count generally is associated
self when these patients assume a prone position, often with an infectious process.
at night when sleeping. Eupnea is a term that refers to
Table 3-19 outlines the differential white blood cell count.
normal breathing, and bradypnea refers to a slow ven-
tilatory rate. Table 3-19: Differential white blood cell count
(1:297–298, 483–484), (7:8, 19, 92), (9:23–25), Blood
(16:167). White Concentration
Blood Cell (mm3) % of Total
IA1g(2)
neutrophils 1,800 to 7,500 40 to 75
71. A. The C(a-v̄)O2 is the abbreviation for the arterial- eosinophils 0 to 600 0 to 6
mixed venous oxygen content difference. This mea- basophils 0 to 100 0 to 1
surement involves the difference between the total lymphocytes 900 to 4,500 20 to 45
arterial oxygen content (CaO2) and the total mixed ve- monocytes 90 to 1,000 2 to 10
nous oxygen content (Cv̄O2). Therefore, the CaO2 –
Cv̄O2 is the C(a-v̄)O2. The C(a-v̄)O2 value in normal
(1:331–33), (9:82–84), (16:178).
subjects is 5 volumes percent (vol %). The normal
range is from 3.0 vol% to 5.5 vol%.
IA2c
The problem presented here can be approached two 73. D. The single-breath nitrogen elimination test can be
ways. One method involves knowing that the person is used to assess the evenness of ventilation throughout
normal and knowing that a V̇O2 of 250 ml/min and a the tracheobronchial tree. The test cannot identify the
cardiac output of 5 liters/min are normal. Therefore, specific location of the obstruction causing maldistrib-
the C(a-v̄)O2 is normal, i.e., 5 vol%. ution of ventilation. The test can, however, provide an
The second way to solve this problem is to use the Fick evaluation of the overall distribution of air throughout
equation. the lungs. The single-breath nitrogen elimination test
(SBN2) can also measure a subject’s closing volume
V̇O2 and closing capacity.
Q̇ T =
C(a  v̄)O2 The tracing in Figure 3-30 illustrates a normal SBN2
where, curve.
Q̇ T = cardiac output (L/min.) The curve has four components on phases. These
phases are defined as follows:
V̇ O2 = oxygen consumption (ml/min.)
phase I: anatomic dead space gas
C(a-v̄)O2 = arterial-mixed venous oxygen phase II: remnants of anatomic dead space gas and ini-
content difference (vol %) tial alveolar emptying (basal and mid-zone alveoli)
Rearranging the equation to solve for the C(a-v̄)O2, phase III: alveolar plateau-predominately basal
and mid-zone alveolar emptying
V̇O2 phase IV: upward deflection signifying emptying
C(a –v̄)O2 =
Q̇ T of apical alveoli

Chapter 3: Clinical Data 153

 80 This procedure enables the CRT to ascertain specific
information about the distribution of air flow and of-
fers much more than a generalized assessment.
N2 CONC.%

30
IV
(2:238–239), (6:83–86), (9:139–140), (11:118–122).
20 III
IA2f
II ‘CV’ RV TLC
10 30%VC 74. A. Measuring the oxygen saturation via pulse oxime-
try (SpO2) provides continuous monitoring of the arte-
I rial oxygen saturation. Positioning the probe where it
0
1 2 3 4 5 6 can be secured to avoid motion artifact is essential.
Closing This continuous monitoring of oxygenation is impor-
Volume (liters) Volume
Residual tant, especially in patients who have lung disease.
Vital Volume
Such patients commonly desaturate abruptly during
Capacity
Closing exercise. Therefore, a pulse oximeter provides data for
Capacity quick intervention if necessary.
Figure 3-30: Components of normal single-breath nitrogen Pulse oximetry data obtained during exercise must be
elimination curve.
used judiciously, however, because the SpO2 might not
The evenness of distribution of ventilation is deter- correlate with the SaO2 during exercise (despite a cor-
mined by the N750–1250 and by the slope of phase III. relation at rest). An arterial blood gas sample should be
The N750–1250 is the change in exhaled nitrogen during obtained to eliminate disparities between the two read-
the exhalation of 500 ml between the 750-ml and ings.
1,250-ml points along the x-axis of the curve.
(AARC Clinical Practice Guidelines for Pulse
The slope of phase III is obtained by placing a line of Oximetry Respiratory Care, 36:1406–1409, 1991),
best fit along the phase III tracing and intersecting it (1:359–361), (4:286–291), (6:183).
with a line of best fit along the phase IV tracing.
IA1a
An abnormal SNB2 curve depicting maldistribution of
ventilation is shown in Figure 3-31. 75. C. The physician’s daily observations are noted in the
patient progress notes. The history and physical exam-
80 ination reflect information obtained at the time of ad-
mission. Physician orders refer to specific treatments
and tests to be performed. The graphic charts are usu-
% Exhaled N2

ally compiled by nursing personnel and depict the pa-

III–IV tient’s vital signs.
(1:33–36).
II
IA1f(5)
I
76. C. A normal caphogram is depicted in Figure 3-32.
0 1 2 3 4 5
This caphogram is composed of three phases. Phase I
Volume (liters) reflects the partial pressure of CO2 leaving the
Figure 3-31: Obstructive lung-disease pattern shown on anatomic dead space. Take note of how low that value
the single-breath nitrogen elimination curve. tends to be. The reason is there is virtually no CO2 in
the atmosphere, and no gas exchange occurs in the
Another test that offers information about the distribu- anatomic dead space. Phase II demonstrates an abrupt
tion of ventilation is the seven-minute N2 washout test. rise in the exhaled CO2 as alveolar emptying begins.
Like the SBN2, it provides general information about Phase II contains traces of alveolar dead space gas and
the distribution of ventilation. gas beginning to leave the alveoli. Phase II signifies
The inhalation of traces of radioxenon (xenon-133) in the alveolar, or CO2, plateau where the exhaled gas
the inspired air provides for the evaluation of regional predominantly contains CO2-rich gas from the alveoli.
changes in the distribution of ventilation. The inhaled The end of the CO2 plateau (phase III) is the partial
radioactive gas emits scintillations from all areas of the pressure of the end-tidal CO2, or PETCO2. The PETCO2
lung receiving ventilation. The film is exposed in lung is approximately equal to the PaCO2. In fact, a 1 to 2
regions receiving air flow and remains dark (undevel- torr PCo2 difference exists between the PaCO2 and the
oped) in regions devoid of air flow. PETCO2 in a normal adult patient.

154 Chapter 3: Clinical Data

 patients who were given a ventilation-perfusion lung
60 scan for pulmonary embolism were false-positive for
50 having this condition.
D
mm Hg 40 C Pulmonary angiography provides a definitive diagno-
30 sis for pulmonary embolism. When a ventilation-
perfusion scan renders uncertain results, pulmonary
20
angiography is performed. This procedure involves us-
10 ing the injection of contrast medium into either the
A B E A
0 pulmonary artery or into one of its branches.
Time (1:216–217, 495–496), (9:155–156).
Figure 3-32: Normal capnogram:
A: Onset of expiration IA1h
A–D: Expiration 79. A. The Apgar score is a standardized scoring system of
A–B: Clearance of air from anatomical newborn infants. This test encompasses five clinical
deadspace signs (heart rate, respiratory effort, muscle tone, reflex
B–C: Exhalation of dead space air mixed irritability, and color) that the newborn displays. Each
with gas from alveoli
clinical sign can be scored 0, 1, or 2 based on the cri-
C–D: Exhalation of gas from alveoli-
alveolar plateau
teria for each score. The higher the Apgar score, the
D: End-tidal CO2 value; onset of inspiration more stable the infant. An Apgar score can range from
D–E: Inspiration of residual air in ventila- 0 to 10.
tory circuit Apgar scores are typically obtained at one minute and
E–A: Inspiration of CO2-free air
five minutes after birth. Sometimes Apgar scores are
(1:363–368), (3:255–262), (4:296–301), (6:146–148), determined more frequently, depending on the new-
(9:257–258), (11:232–239), (16:313–318). born’s condition. The Apgar scoring system is shown
in Table 3-20.
IA1g(1) Table 3-20: The Apgar scoring system
77. C. The pumping of the blood from the heart and the
elasticity of the arterial vessels produces the blood pres- Sign 0 1 2
sure in the systemic circulation. The blood pressure is less than greater than
commonly measured by a blood-pressure cuff (sphyg- Heart Rate absent 100 bpm 100 bpm
momanometer). The blood-pressure cuff is placed
around the upper arm and is pressurized until the arter- Respiratory gasping,
Effort absent irregular good
ial blood flow stops. The bell of a stethoscope is placed
over the brachial artery in the antecubital fossa. As pres- Muscle
sure is released slowly from the cuff, blood flow re- Tone limp some flexion active motion
sumes through the compressed artery. The turbulent Reflex
blood flow (pulsations) can be heard through the stetho- Irritability no response grimacing crying
scope. The initial sounds (Korotkoff sounds) reflect sys-
tole. As pressure continues to be released slowly from body pale or blue, body pink, completely
Color extremities blue extremities blue pink
the cuff, the sounds fade. The point at which the Ko-
rotkoff sounds become muffled is the diastolic pressure.
(1:1002–1003), (9:197).
The blood pressure is expressed as the systolic-dias-
tolic ratio. A blood pressure that exceeds 140/90 mm IA1a
Hg is classified as hypertension, and a blood pressure
80. B. The history of the present illness is a narrative that
less than 95/60 mm Hg is categorized as hypotension.
chronologically relates the specific components of
(1:304), (9:44), (16:162). each symptom referring to the chief complaint. This
history establishes the basis for the diagnostic work-
IA2a ups and physical examinations that will be performed
78. A. The initial step in attempting to diagnose pul- to determine the diagnosis.
monary embolism is using a ventilation-perfusion lung The patient must be encouraged to speak openly about
scan. This diagnostic procedure is not definitively di- each symptom and aspect of the chief complaint.
agnostic for pulmonary embolism, however. In fact, Therefore, the interviewing technique is critical. The
one clinical study showed that 12% to 14% of those interviewer must ask open-ended questions and make

Chapter 3: Clinical Data 155

 statements that elicit complete descriptions. For exam- IA1f(2)
ple, the questions, “How often does your shortness of 85. A. Each tidal breath (VT) is comprised of two compo-
breath occur?” and “Describe how your sputum looks” nents, i.e., dead space volume (VD) and alveolar vol-
should be asked. Both the preceding question and state- ume (VA). Hence, we have the following formula:
ment enable the patient to elaborate on the subject and
to be more encompassing in the discussion. VT = VD  VA

Questions that can be answered by merely stating yes The ventilatory rate (f) can be incorporated into this
or no must be avoided. For instance, “You cough only equation. When f is added, the formula becomes:
in the morning, right?” is a close-ended question that f(VT) = f(VD)  f(VA)
must be avoided.
Alternatively, the expression can be presented as such:
(1:296–297), (9:16).
V̇E = V̇D  V̇A
IA1e where,
81. D. The most appropriate time to review a patient’s
V̇E = exhaled minute ventilation (liters/minute)
chest X-ray is after the history of the present illness
has been obtained and after the physical examination V̇D = dead space ventilation (liters/minute)
has been performed. The data and information derived
V̇A = alveolar ventilation (liters/minute)
from these two processes can offer insight toward un-
derstanding and interpreting the abnormalities viewed The following data from the problem are needed to de-
on the chest radiograph. termine the minute ventilation (V̇E):
(9:156). • ventilatory rate (12 breaths/minute)
• minute ventilation (6.00 liters/minute)
IA1b • patient’s ideal body weight (150 lbs)
82. D. Pectus carinatum, also called pigeon breast, refers The ideal body weight is important from the standpoint
to the anterior protrusion of the sternum. Pectus exca- that it provides an estimate of the patient’s dead space
vatum describes sternal depression. Barrel chest is an volume. The guideline is that each pound (1 lb) of ideal
abnormal increase in the anterior-posterior diameter of body weight is equivalent to one milliliter (1 ml) of
the chest. Kyphosis is an abnormal anteroposterior anatomic dead space. Therefore, because this patient
curvature of the thoracic spine. has an ideal body weight of 150 lbs, the amount of
(1:307), (9:56), (7:581), (16:164, 1122). anatomic dead space is approximately 150 ml.
Sufficient information is now available to calculate
IA1g(1) this patient’s V̇A. This calculation is outlined here.
83. C. When a pulse rate is obtained, the following three STEP 1: Determine the V̇D.
features of the pulse rate need to be evaluated:
V̇D = f  VD
• rate
• rhythm = (12 breaths/minute)(150 ml/breath)
• strength = 1,800 ml/minute, OR
A patient’s pulse can be obtained from a variety of ar- = 1.80 liters/minute
terial sites. These include the radial artery, brachial
artery, femoral artery, and carotid artery. When a pa- STEP 2: Calculate the V̇A.
tient’s blood pressure is low (e.g., during CPR), as- V̇A = V̇E  V̇D
sessing the pulse at a central location (carotid or
femoral artery) is more appropriate than palpating a = 6.00 liters/minute  1.80 liters/minute
peripheral pulse (radial artery). = 4.20 liters/minute
(1:303–304), (9:42), (16:162). (1:211–12), (7:685–687), (17:27–28).

IA2a IA1h
84. C. A needle biopsy of a peripheral carcinoma of the 86. B. The designation G3, P2, Ab0 signifies that the ex-
lung can be performed with the assistance of a CT pectant mother is in her third pregnancy, has delivered
scan. A CT scan provides an extremely clear view, es- two live births, and has had no abortions. The G repre-
pecially compared with radiography. sents gravida which means pregnant woman. The P
(9:152). stands for para which means a woman who delivers a

156 Chapter 3: Clinical Data

 live infant. The Ab refers to abortion, which means the tilation by the frequency and converting the quotient to
delivering of a dead infant. milliliters. Note the following formula:
(9:196). V̇ E liters/minute
= VT or = liters/breath
f breaths/minute
IA2d
87. A. Hypoventilation will result in an increased PaCO2 9.6 liters/min.
= 0.96 liter/breath
and a respiratory acidosis. Chronic CO2 retention, of 10 breath/min.
course will result in an increased PaCO2 and a com-
pensated (near normal) pH. At the same time, because then,
carbon dioxide is passively permeable across the (liters/breath)(ml/liter) = ml/breath, that is,
blood-brain barrier, cerebrospinal fluid (CSF) carbon- (0.96 liter/breath)(1,000 ml/liter) =
dioxide tension will also increase. 960.0 ml/breath
The two fluid compartments are in dynamic equilib- (1:211–212), (7:685–687).
rium in terms of the CO2 partial pressure. The in-
creased CSF PCO2 causes stimulation of the central IA2b
chemoreceptors located on the ventral lateral surface
90. B. A gram stain is the method of staining microorgan-
of the medulla. Stimulatory (hyperventilatory) signals
isms by using a violet stain, followed by an iodine so-
are sent to the medulla. The muscles of ventilation,
lution, decolorizing with alcohol, and counterstaining
however, cannot carry out the hyperventilation be-
with safranin. The Ziehl-Neelsen acid-fast stain is used
cause chronic CO2 retention is characterized by de-
to identify sputum samples suspected of containing
ranged respiratory mechanics (i.e., impaired air flow
Mycobacterium tuberculosis. Gomori’s methenamine
and V̇A /V̇C mismatching). Therefore, bicarbonate is
silver and the periodic acid-Schiff stains are for iden-
actively transported from the blood, across the blood-
tifying fungal organisms.
brain-barrier, and into the CSF to normalize the CSF
pH back to 7.32. (1:622––25), (9:96–97), (16:282–286), (17:514).
The CSF compensatory mechanism eliminates the
stimulus for the central chemoreceptors. Therefore, a IA1f(3)
person who has chronic CO2 retention will have an in- 91. C. Body plethysmography can be used to determine
creased arterial PCO2 and an increased CSF PCO2— the patient’s thoracic gas volume (VTG), airway resis-
and, as a consequence to the compensatory events, the tance (Raw), and the specific conductance (SGaw). The
arterial blood pH will be near normal but slightly aci- VTG, or FRC, is measured by having the patient pant
demic, while the CSF pH will be normal (7.32). through an unobstructed airway and then suddenly
through an obstructed airway.
(1:287, 288), (16:130).
The VTG, Raw, and SGaw can be measured at the same
IA2a time with a combined breathing maneuver. Nonethe-
less, optimal panting frequencies differ for Raw and
88. A. The study of body fluids and secretions for the pres-
VTG determinations. Wuite often, these measurements
ence of cellular material is called cytology. Frequently,
are obtained separately.
the presence of a malignancy and even its type can be
identified via cytology. When the VTG is measured, the VTG does not equal the
FRC—because the shutter closes at a volume different
According to the AARC Clinical Practice Guidelines
from the FRC. Because the change in volume from
for Fiberoptic Bronchoscopy Assisting, one of the
tidal breathing was stored at the onset of the proce-
many indications for flexible bronchoscopy include
dure, this volume is either added or subtracted from
suspicious or positive sputum cytology results.
the measurement to determine the VTG. Most people
(AARC Clinical Practice Guidelines for Fiberoptic pant above their FRC level. Therefore, their VTG ends
Bronchoscopy Assisting). up slightly greater than the FRC.
During the process of measuring the FRC, the Raw
IA1f(2) and SGaw values are also determined. The Raw is
89. A. Minute ventilation is the volume exhaled per measured in cm H2O/L/sec. The airway conductance
minute; it is the product of the volume exhaled during (Gaw) is the reciprocal of the Raw; that is,
each breath or tidal volume (VT) and the number of
breaths per minute (f). When given the minute ventila- 1
= Gaw
tion and the breathing frequency, the average tidal Raw
volume can be calculated by dividing the minute ven-

Chapter 3: Clinical Data 157

 The specific conductance is calculated by dividing the V̇E = tidal volume (VT)  ventilatory rate (f)
Gaw by the FRC. The units for SGaw are L/sec/cm
Because, the person in this problem has a tidal volume
H2O/L. Dividing the Gaw by the FRC enables the
of 500 ml and a ventilatory rate of 12 breaths/minute,
comparison of values in different persons, or in the
the V̇E can be determined as follows:
same subject, after the administration of a bron-
chodilator or after a bronchial challenge. V̇E = 500 ml/breath  12 breaths/minute
(1:202, 938), (6:55–57), (11:130–134). = 6,000 ml/minute or 6.0 liters/minute
Adult minute ventilation averages between 5 and 10
IA1f(2)
liters/minute.
92. C. An arterial PCO2 of 25 mm Hg is below the normal
range of 35 to 45 mm Hg, indicating that the patient (1:211–212), (7:685–687), (17:26–28).
has exhaled excessive amounts of carbon dioxide. The
alveolar ventilation is the volume breathed per minute IA1f(2)
that ventilates functioning alveoli; alveolar ventilation 95. C. The alveolar minute ventilation is the volume of air
is inversely proportional to the arterial PCO2. Hyper- that enters the alveoli per minute. To obtain the alveo-
ventilation or excessive alveolar ventilation would re- lar minute ventilation, subtract the estimated anatomic
sult in a reduced level of carbon dioxide in the arterial deadspace volume (VD) from the tidal volume (VT).
blood. Hypoventilation would result in an increased Remember, the assumption here is that no alveolan
amount of carbon dioxide in the arterial blood. dead space exists. Then, multiply the remainder (alve-
Tachypnea refers to a breathing frequency greater than olar volume  VA) by the ventilatory rate. The steps
normal, and hyperpnea refers to having tidal volumes are outlined here.
greater than normal. Patients who are tachypneic or
STEP 1: Determine the alveolar volume (VA). Use the
hyperpneic might have a normal arterial PCO2.
guideline that states 1 ml of anatomic dead space ex-
(1:265, 267), (4:111), (7:245–246), (10:101, ists for each pound of ideal body weight. Therefore, a
157–158), (16:167). 150-lb person (ideal body weight) has 150 ml of VD.
VT = VD  VA
IA1f(2)
Solving for VA,
93. B. A normal VT for a healthy individual is usually 5 to 7
ml/kg of ideal body weight. This value should not be VA = VT – VD
confused with the guideline for setting the tidal volume
= 500 ml – 150 ml
for mechanical ventilation, which is generally 10–15
ml/kg. Even this clinical guideline varies with the clini- = 350 ml
cal situation that is confronted. For example, COPD pa-
STEP 2: Multiply the VA by the ventilatory rate to cal-
tients should receive only 7–10 ml/kg (IBW), especially
culate the alveolar minute ventilation (V̇A).
if they are severely hyperinflated. The purpose for using
this lower volume range is to reduce the risk of causing V̇A = (VA)(f)
auto-PEEP and barotrauma. Asthmatic patients (status
= (350 ml)(12 breath/minute)
asthmaticus) who require mechanical ventilation should
receive volumes in the range of 8–10 ml/kg (IBW). = 4,200 ml/minute or
These patients already have hyperinflation; therefore,
4.2 liters/minute
the risk of barotrauma needs to be minimized.
(1:211–212), (7:685–687).
For NBRC exams, however, candidates should use the
standard 10–15 ml/kg (IBW) as the tidal volume
guideline for patients who are receiving mechanical IB10a
ventilation. 96. A. The ECG strip shown in Figure 3-33 represents si-
nus bradycardia at a rate of 56 to 58 beats/minute.
(1:516), (16:620), (18:717).
Sinus bradycardia is defined as a sinus node pace-
IA1f(2) maker rate of less than 60 per minute.
94. D. The minute ventilation represents the amount of air Sinus bradycardia can occur in normal persons who
brought into the lungs during one minute of breathing. have a strong degree of parasympathetic tone. Sinus
The volume of air is customarily measured during ex- bradycardia is frequently present in people who are
halation. Minute ventilation is represented by the sym- physically fit and routinely engage in aerobic activity.
bol V̇E. The calculation for minute ventilation is given These people exhibit what is termed physiologic
as follows: bradycardia, rather then pathologic bradycardia.

158 Chapter 3: Clinical Data

 Figure 3-33: Sinus bradycardia.

Sinus bradycardia is also found in people who are ex- becomes greater than one. Ordinarily, this ratio is less
periencing a reduced metabolic rate, e.g., hypothermia than one. The diagram in Figure 3-34 illustrates this
and sleep. The abrupt appearance of sinus bradycardia relationship.
in patients who are having cerebral edema or subdural
(1:317–318), (7:580), (9:70–71), (16:167–168), (18:91).
hematoma results from the stimulation of the parasym-
pathetic center by the increased intracranial pressure.
160°
When the heart rate is regular, the number of large
boxes (0.2 second) between two consectuive QRS
complexes are counted. The sum is divided into 300.
On the other hand, if the heart rate is irregular, the A.
number of QRS complexes in a six-second interval can
be counted and multiplied by 10.
(2:225).

IB1d
97. C. Assessment of capillary refill involves applying >180°
firm pressure for a few seconds to the fingernail bed of
a patient until the fingernail blanches. The time elaps-
ing for the nail bed to regain its normal pinkish color
signifies the status of the patient’s cardiac output. If
B.
the patient’s cardiac output is compromised, capillary
IPD
refill is slow. Several seconds elapse before the nail DPD
bed becomes pink. Normally, the capillary refill occurs
in about three seconds or less.
Figure 3-34: (A) normal angle ( 160º between nail bed
Therefore, if the capillary refill time exceeds three sec- and root of nail; (B) digital clubbing with angle greater than
onds, a decreased cardiac output with hypotension is 180º (DPD:IPD ratio greater than 1).
presumed.
IB2b
(1:318), (9:71).
99. C. In this situation, the tip of the endotracheal slipped
down the carina and into the right mainstem bronchus.
IB1a The right lung experienced barotrauma by developing
98. D. Digital clubbing is a painless enlargement of the ter- a pneumothorax.
minal phalanges of the fingers and toes of patients who
have (1) cyanotic heart defects, (2) cystic fibrosis, and (3) Radiographically, the visceral pleura is forced away
bronchogenic carcinoma. Although the specific etiology from the chest wall. The air occupying the intrapleural
is unknown, chronic hypoxemia appears to be a common space is devoid of lung patterns and is hypertranslu-
link among the diseases associated with digital clubbing. cent. The collapsed lung often appears more opaque as
it becomes more compressed and as the radiologic im-
Normally, the angle between the nail bed and the root of age becomes more radiopaque.
the nail (adjacent or proximal skin) is approximately
160º. As digital clubbing develops over the course of Palpation is likely to reveal unilateral chest-wall expan-
time, that angle gradually widens to 180º or more. The sion. The intrapleural air in the right hemithorax pushes
skin in the area stretches and glistens as this condition the mediastinum to the contralateral (left) side. As the
advances. The nail progressively thickens and curves mediastinum shifts, tracheal deviation to the left also oc-
until it takes on a bulbous appearance. The ratio of the curs. This finding can be ascertained by palpation.
distal phalangeal depth to the interphalangeal depth (1:205–206), (9:162–163), (16:607–711).

Chapter 3: Clinical Data 159

IB9c cardiac output to maintain adequate oxygenation. A
100. C. The arterial oxygen saturation (SaO2) obtained dur- slow heart rate can be indicative of shock, reaction to
ing an arterial blood gas sample analysis is a calcu- medications, or cardiac dysrhythmias.
lated value, rather than a directly measured value. (1:303–304), (9:41–42), (15:432), (16:162).
(Only three variables are directly measured in a blood-
gas analyzer: pH, PaCO2, and PaO2). Blood-gas ana- IB1b
lyzers calculate the SaO2 based on the measured PaO2
103. D. Retractions refer to depression of the skin around
and pH at 37ºC, along with assuming a normal P50. Be-
bony structures during inspiration. Because an infant’s
cause carbon monoxide will be bound to some amount
chest wall is only slightly less compliant than the lung,
of hemoglobin, the calculated oxyhemoglobin (SaO2)
any decrease in lung compliance can result in the chest
value would be overestimated. The same situation is
wall collapsing inward as the diaphragm contracts.
true of methemoglobin.
The adult chest wall is more calcified and has greater
A co-oximeter should be used to measure the amount musculature, making retractions less likely (except
of carboxyhemoglobin (COHb) and oxyhemoglobin with severe obstruction).
(O2Hb).
(1:307), (9:57, 202), (15:436–437), (18:91).
(1:358–363), (4:286–290), (6:144–145, 276),
(9:267–268), (11:226–228, 231), (16:310–312). IB8a
104. D. Acute epiglottitis is an extremely dangerous condi-
IB4a tion causing upper-airway obstruction in young chil-
101. C. Laryngotracheobronchitis (croup) often afflicts dren. This desease is characterized by sudden onset,
children ranging from six months to three years of age. high fever, severe respiratory distress, drooling, and
The most common viral causes are parainfluenza type dysphagia. This disease usually affects children be-
I and type II, respiratory syncytial virus (RSV), and tween three and six years old and is caused by Hemo-
the influenza virus. Laryngotracheobronchitis is char- philus influenzae type B. The differential diagnosis
acterized by subglottic swelling of the upper airway. between epiglottitis and laryngotracheobronchitis
Because of the narrowing of the trachea and mainstem (croup), which is a relatively benign viral infection,
bronchi, stridor is often associated with this condition. must be made. Acute epiglottitis may cause sudden,
complete airway obstruction that precludes endotra-
Tracheomalacia is the softening of the tracheal carti-
cheal intubation. Emergency tracheostomy is then nec-
lages. As a result, the trachea narrows and may col-
essary if hypoxic brain damage and death are to be
lapse during a deep inspiration as the intraluminal
averted. Direct visualization of the epiglottis, although
pressure becomes more subatmospheric. A forceful
diagnostic, is risky—because any stimulation of the
exhalation (e.g., during coughing) may also cause the
pharynx may trigger complete obstruction. Procedures
trachea to collapse. If the upper part of the trachea is
which may agitate the child are to be avoided. If diag-
affected by this pathophysiology, stridor may result.
nosis is uncertain, a lateral neck radiograph is useful.
Post-extubation upper-airway inflammation can cause Positive findings of epiglottitis include a bulbous,
the intraluminal space to diminish. Rapid flow of air swollen epiglottis with thickened aryepiglottic folds.
through the partially obstructed upper airway produces The misshapen epiglottis resembles a thumb and is
the stridor. called the thumb sign.
Stridor is sometimes found in epiglottitis. Airway ob- (1:162–163, 999, 1,039–1,040), (16:597–598, 983–984).
struction occurs at the laryngeal inlet (i.e., the epiglot-
tis and aryepiglottic folds become swollen). IB9a
(1:1038–1039), (9:67), (18:196–203). 105. B. Capnography provides a means of measuring the
exhaled partial pressure of carbon dioxide throughout
IB2a exhalation. In fact, it monitors the inspired and exhaled
gas. Of particular interest is the measurement of the
102. D. The pulse should be assessed for rate, rhythm, and
partial pressure of the end-tidal CO2, or PETCO2. The
strength. A decrease in one of these areas in the periph-
PETCO2 is generally the highest level of the exhaled
eral pulses could be indicative of a decreased cardiac
PCO2, and is achieved immediately before inspiration.
output. Weak pulses in the lower extremities with ade-
quate pulses in the peripheries indicates the presence of According to the AARC Clinical Practice Guidelines
atherosclerotic vascular disease. The amount of oxygen for Capnography/Capnometry during Mechanical Ven-
getting to the circulatory system is a direct function of tilation, not all mechanically ventilated patients re-
the heart. An increase in the heart rate in the presence quire capnography. No absolute contraindications
of lung disease is an attempt by the body to increase the exist for its use, however.

160 Chapter 3: Clinical Data

 Table 3-21 delineates between some causes of in- only in the extremities, ear lobes, lips, and the tip of
creased and decreased PETCO2 measurements. the nose.
Table 3-21 Central cyanosis is typically caused by the lung’s in-
ability to oxygenate the mixed venous blood flowing
Decreased PETCO2 Increased PETCO2 through the pulmonary vasculature or by the shunting
of blood directly into the arterial end of the systemic
• breathing circuit • hypoventilation
disconnection
circulation, without flowing through the pulmonary
circulation. Central cyanosis appears as a bluish dis-
• decreased cardiac • increased CO2
coloration of a patient’s thorax and abdomen, includ-
output production (V̇CO2)
ing areas such as the oral mucosa.
• endotracheal tube • increased cardiac
obstruction output Patients who are polycythemic are at greater risk of de-
• pulmonary embolism • NaHCO3 infusion veloping cyanosis than those who are anemic. Because
(decreased pulmonary polycythemic patients have an oxygenation problem to
perfusion) begin with, more oxygen is required to saturate an ab-
• hyperventilation normally high hemoglobin concentration. Therefore,
they are more likely to have 5 g% or more of desatu-
rated hemoglobin in total circulation.
(1:363–368), (3:255–262), (4:296–301), (6:146–148),
(9:257–258), (11:263–268), (16:313–314). Anemic patients often oxygenate sufficiently and can
saturate most of their hemoglobin. Consequently, hav-
IB5e ing 5 g% or more of reduced hemoglobin in an anemic
state is more difficult to achieve. Furthermore, anemic
106. A. This patient has mild COPD with an FEV1 of 60% patients have less hemoglobin to begin with; therefore,
of predicted. She is not a chronic CO2 retainer. Her they must have a significantly low oxygen saturation
PaCO2 is normal, and her level of dissolved arterial for 5 g% of hemoglobin to be reduced.
PO2 is normal. Arterial blood gases are essentially nor-
mal in mild COPD. For such a patient, the nutritional The units grams % in reference to the hemoglobin con-
balance is as shown in Table 3-22. centration means “grams of hemoglobin contained in
100 ml of blood.” This unit (g%) differs from another
Table 3-22 unit used in quantifying oxygen transport in the blood.
That unit is volumes %. Volumes % means milliliters
Substrate Percentage
of a gas (O2 or CO2) contained in 100 ml of plasma or
protein 15%–20% blood. Be sure to not confuse g% with vol %.
carbohydrate 50%–60%
(1:318), (2:260), (4:96–97), (9:58).
fat 20%–30%
IB1b
For chronic CO2 retainers, the diet should be individu- 108. B. The diaphragm might be nonfunctional in patients
ally established. who have neuromuscular disease or spinal-cord in-
(1:444, 1077–1078), (2:273), (9:943–944). juries. In such cases, the accessory muscles (scalene
and sternomastoid) become active during quiet respira-
IB1a tion. Normally, the abdomen moves gently out on in-
spiration and in on expiration. If the abdomen sinks in
107. A. Cyanosis is a bluish discoloration of the skin and/or markedly on inspiration (paradoxical abdominal move-
mucous membranes caused when five grams % or ment), however, accessory muscle usage is occurring—
more of hemoglobin in total circulation is desaturated. suggesting diaphragmatic paralysis or fatigue.
One needs to focus on the word “total.” The term “to-
tal” refers to the entire circulatory network, i.e., the en- (1:308), (9:61–62, 227–228), (15:437), (16:348).
tire blood volume (arterial and venous blood).
IB10a
Cyanosis can manifest itself as peripheral cyanosis
109. B. Ventricular fibrillation is characterized by a chaotic
or central cyanosis. Peripheral cyanosis, also called
electrical activity and totally disorganized myocardial
acrocyanosis, frequently results from a reduction in
activity in which essentially no cardiac output devel-
systemic blood flow, as in low cardiac output states.
ops (refer to Figure 3-35).
When the cardiac output is low, the blood moves
slowly through the systemic capillaries. Consequently, The myocardium is frequently salvageable if the elas-
the tissues extract more oxygen from the blood. Pe- tical rhythm is restored. This dysrhythmia is easily
ripheral cyanosis appears as a bluish discoloration recognized because it lacks an organized pattern.

Chapter 3: Clinical Data 161

 Figure 3-35: Ventricular fibrillation.

Ventricular fibrillation is a life-threatening dysrhyth- dition is associated with chronic oxygen depletion at
mia and frequently causes sudden death. the tissue level and is seen in patients who have cystic
fibrosis, COPD, and chronic cardiovascular disease.
(1:331), (9:189), (16:857).
(1:317–318), (7:580), (9:70–71), (16:167–168), (18:91).
IB9b
110. D. The lungs are comprised of numerous volumes and IB7e
capacities. The spirogram in Figure 3-36 illustrates 112. D. A pleural effusion is fluid in the intrapleural space.
these volumes and capacities. The fluid might be pus, chyle, or blood. Table 3-23 lists
the type of pleural effusion caused by specific fluids in
the intrapleural space.
Table 3-23
IRV Fluid Pleural Effusion
IC
VC pus empyema
TLC chyle chylothorax
VT blood hemothorax

ERV
The degree of pulmonary impairment caused by a pleural
FRC
effusion depends on the volume of fluid occupying the in-
RV RV trapleural space. Pleuritic pain often accompanies a
pleural effusion and can result in decreased lung volumes,
Figure 3-36: Spirogram demonstrating lung volumes and which in turn can impair a patient’s ability to cough.
capacities.
On a posteroanterior (P-A) chest radiograph, a pleural
Notice where the tidal volume is situated. The tidal vol- effusion might exhibit a slightly obscured costophrenic
ume occupies the region between the inspiratory reserve angle if the volume of the pleural effusion is small.
volume (IRV) and the expiratory reserve volume (ERV). The same pleural effusion (small effusion) can often
The tidal volume (VT) can be measured with a spirom- be better viewed on a lateral decubitus projection.
eter during either a normal inspiration or exhalation. A substantial pleural effusion fills the area of the
The total volume of gas inspired or expired over the costophrenic angle and obliterates the costophrenic an-
time of one minute is the minute ventilation (V̇E). The gle on both PA and lateral decubitus projections.
minute ventilation is actually the tidal volume multi- Pulmonary nodules are round, opaque lesions within
plied by the respiratory rate (f). That is, the lungs. These lesions often exceed 1 cm in diameter.
V̇ E = VT  f Nodules sometimes produce lung cavities that ulti-
mately calcify.
The volume of gas exhaled during a forceful exhala-
tion is the FVC. The volume of gas removed from the Atelectasis is defined as collapsed alveoli. Atelectatic
lungs during a complete, non-forceful exhalation is the (or collapsed) alveoli, do not receive ventilation, there-
vital capacity (VC) or slow vital capacity (SVC). fore, they do not participate in gas exchange. Atelecta-
sis can be confined to a small area of the lung, in an
(11:82–84), (16:129), (20:37). entire lobe, or throughout both lungs. Atelectasis is
caused by an airway obstruction such as excessive se-
IB1a cretions or foreign body aspiration.
111. B. Clubbing of the digits is a painless enlargement of Atelectatic regions appear as increased densities upon
the distal phalanges of the fingers and toes. This con- radiographic examination. The increased densities do

162 Chapter 3: Clinical Data

 not become prominent until a substantial volume of air Therefore, by using the data presented in the problem,
is absorbed. Other radiographic characteristics that are you can calculate the static compliance as follows:
sometimes associated with atelectasis include (1) dis-
0.6L
placement of interlobar fissures, (2) mediastinal shift, Cstatic = = 0.05 L/cm H2O
and (3) pulling up the diaphragm on the affected side. 17 cm H2O – 5 cm H2O
(1:406, 773), (9:160–161, 169–179), (20:271–272, 320). The formula for the dynamic compliance (Cdyn) is the
tidal volume divided by the PIP minus the PEEP.
IB4c Hence,
113 A. Ordinarily, during inspiration the systolic blood VT
pressure falls slightly, no more than 3 to 4 mm Hg. A Cdyn =
condition, called pulsus paradoxus (paradoxical pulse) PIP – PEEP
occurs when the systolic blood pressure falls about 10 For the patient who is presented in this problem, the
mm Hg during each inspiration. The phenomenon is Cdyn would have been
sometimes seen in acute asthmatic attacks and cardiac
tamponade. 0.6 L
Cdyn = = 0.03 L/cm H2O
The cause of this occurrence is believed to be a sub- 25 cm H2O – 5 cm H2O
stantial drop in intrapleural and intrathoracic pressure The dynamic compliance differs from the static com-
(more negative or more subatmospheric) produced by pliance in that the dynamic compliance contains both
the inspiratory muscles of ventilation. The drastic fall the static and dynamic components involved in lung
in intrathoracic pressure increases venous return to the inflation. The static component is the compliance
right ventricle and decreases the cardiac output of the value, which is obtained during no airflow conditions
left ventricle. Furthermore, the increased venous return (either end-inspiration or end-exhalation). The dy-
increases the right ventricular filling pressure, causing namic component is pressure generated to overcome
the interventricular septum to bulge toward the left ven- airway resistance. The dynamic component is present
tricle. Therefore, the left ventricular filling pressures only during times of air flow through the patient-
decrease, and the left ventricular cardiac output is fur- ventilator system.
ther compromised. Hence, a decreased systolic pres-
sure is generated during such an inspiratory effort. The static compliance contains only the static compo-
nent involved in lung inflation. The plateau (static)
Pulsus alternans is an alternating succession of weak pressure is obtained by instituting an inflation hold or
and strong pulses. Pulsus alternans is generally not as- inspiratory pause. The inspiratory hold is equivalent to
sociated with pulmonary disease, but it does, however, a breath-holding maneuver. After the PIP is achieved,
implicate the possibility of left-ventricular failure. the inspiratory pause occurs—and the plateau pressure
The term respiratory alternans describes the periodic is obtained.
transition from normal (diaphragmatic) breathing to The difference between the peak inspiratory pressure
accessory muscle usage. Respiratory alternans is often and the plateau pressure provides for the pressure gen-
a harbinger of impending ventilatory failure. erated to overcome airway resistance (air flow must be
Abdominal paradox describes the movement of the ab- present). The formula for the pressure generated to
dominal musculature inward during inspiration and the overcome airway resistance is shown below.
bulging of the abdomen outward during exhalation. PIP – Pplateau = pressure generated to over-
Abdominal paradox is a sign of diaphragmatic fatigue come airway resistance
and is also a sign of impending ventilatory failure.
In the problem posed here, the pressure generated to
(1:304–305, 923), (9:44, 58), (16:163, 1004). overcome airway resistance is calculated as follows:
25 cm H2O – 17 cm H2O = 8 cm H2O
IB9d
114. B. While a patient receives mechanical ventilation, These measurements assist in establishing trends in the
two types of compliance measurements can be made: status of the lungs; i.e., whether pulmonary compli-
static compliance and dynamic compliance. The static ance is changing and/or whether airway resistance is
compliance (Cstatic) is calculated by dividing the tidal changing. Additionally, these measurements help
volume (VT) by the plateau pressure (Pplateau) minus the guide the application of PEEP or CPAP.
PEEP. That is, (1:937–938), (7:266, 695–696), (16:1127–1128),
VT (19:254).
Cstatic =
Pplateau – PEEP

Chapter 3: Clinical Data 163

IB1a IB3
115. B. Cyanosis is a blue coloration of the skin and mucous 117. C. Percussion is the practice of tapping the thorax to
membranes that results from the presence of unsaturated assess the underlying tissue. As the CRT percusses the
hemoglobin. Cyanosis occurs when 5 grams percent (5 thorax, sounds and palpable vibrations are produced.
g%) or more of reduced hemoglobin is present in total The CRT places the middle finger of his non-dominant
circulation. A patient who has severe anemia might not hand against the patient’s thorax. The middle finger is
demonstrate cyanosis even with severe hypoxemia. positioned parallel to the ribs. The palm of the non-
dominant hand is held away from the thorax, as are the
The calculation illustrated can be used to determine the
remaining fingers. Therefore, only the tip of the mid-
average amount of unsaturated hemoglobin in the blood.
dle finger contacts the patient’s chest wall.
GIVEN: [Hb] 15 g%; SaO2 97.5%; Sv̄O2 75%
With the middle finger of his dominant hand, the CRT
PROBLEM: Solve for the total amount of unsaturated sharply strikes the finger in contact with the patient’s
hemoglobin in circulation. thorax. The percussion sound, or note, produced from
percussion of normal lung tissue is termed normal
STEP 1: Determine both the arterial and venous un-
resonance. Normal resonance can be described as a
saturations.
moderately low-pitched sound. The percussion note
A. Arterial B. Venous created by percussing over hyperinflated lung regions
is referred to as either increased resonance or hyper-
100.0% saturation 100.0% saturation resonance. Lung conditions presenting hyperreso-
– 97.5% arterial saturation –75.0% venous saturation nance via percussion are (1) asthma, (2) pulmonary
2.5% arterial unsaturation 25.0% venous unsaturation emphysema, and (3) pneumothorax (affected side). All
three conditions manifest air trapping.
STEP 2: Calculate the amount of hemoglobin that is Another abnormal sound resulting from percussion is
unsaturated in both the arterial and venous circula- described as dull or flat. This sound is of high pitch
tions. and short duration. Dull or flat percussion notes sig-
A. Arterial B. Venous nify the presence of (1) lung consolidation, (2) pleural
effusion, (3) pleural thickening, and (4) atelectasis.
15 g% Hb contentration 15 g% Hb concentration
Subcutaneous emphysema, also known as crepitus,
× 0.025 arterial unsaturation × 0.25 venous unsaturation
0.375 g% unsaturated 3.75 g% unsaturated produces a coarse, crackling sound and sensation
when palpated.

STEP 3: Calculate the average amount of unsaturated (1:308–310), (7:21–22), (9:61), (16:170–171).
hemoglobin in total circulation.
IB8a
0.375 g%  3.75 g%
= 2.06 g% 118. B. Both subglottic stenosis and croup (laryngotracheo-
2 bronchitis) produce narrowing of the airway below the
The values presented in this example calculation are glottis. Radiographically, they both display the steeple
normal values. Therefore, the degree of hemoglobin sign on a neck film. The steeple sign results from the
unsaturation is less than 5.0 g%, which means that narrowing of the region below the glottis.
cyanosis would not be present. In the case of subglottic stenosis, a congenital airway
(1:318), (9:50, 58, 71, 112), (15:668). obstruction, soft tissue thickening from the vocal cords
to the cricoid cartilage occurs. Croup, on the other
IB1b hand, is an infectious process, caused by a virus
(parainfluenza viruses and respiratory syncytial virus)
116. D. Appropriate questions when interviewing a patient or rarely by a single bacterium (Hemophilus influenzae
concerning sputum production should include the type B, Staphylococcus aureus, and group A Strepto-
amount, color, consistency, and odor of the secretions. coccus pyogenes). The resulting inflammatory process
Information such as hemoptysis and how long the pro- affects the larynx, trachea, and large airways.
ductive cough has been present are essential. When
questioning a patient about the amount of secretions, (1:1038–1039), (9:67), (18:196–203).
she should be asked to state the amount objectively,
rather than subjectively (i.e., “Do you cough up a ta- IB4b
blespoon full or a half-cup of mucus?”)
119. A. The heart sounds M1 and T1 are produced by the
(1296–298), (9:11–13), (15:426), (16:156–157). closure of the mitral valve and tricuspid valve, respec-

164 Chapter 3: Clinical Data

 tively, during the first heart sound (S1). The S1 an- IB10c
nounces the onset of ventricular systole. Normally, the 123. D. Because mixed venous blood is not available (a
two sounds (M1 and T1) are indistinguishable, because PAC has not been inserted), the following shunt equa-
S1 (first heart sound) is perceived as one sound. In pa- tion is used after having the subject breathe an FIO2 of
tients who have right bundle branch block, the M1 and 1.0 for at least 20 minutes.
T1 sounds are separate (i.e., splitting of the S1 sound).
Q̇ S (PAO2  PaO2)(0.003)
The heart sounds A2 and P2 coincide with the closure =
of the mitral valve and tricuspid valve, respectively, Q̇ T (CaO2  Cv̄O2)  (PAO2  PaO2)(0.003)
during the second heart sound (S2). The S2 signals the Again, because mixed venous blood is not available to
initiation of ventricular diastole. During exhalation, allow for the calculation of the total mixed venous
the two sounds are normally synchronous. The S2 oxygen content (Cv̄O2), the arterial-mixed venous
sound is split, however, during systemic arterial hy- oxygen content difference C(a-v̄)O2 must be estimated.
pertension (increased A2 audibility) and during pul- Because this patient has a normal cardiac output and
monary hypertension (increased P2 audibility). perfusion status, the C(a-v̄)O2 can be estimated at 4.5
(14:133–135). to 5.0 vol%.
Before this shunt equation can be used, the alveolar
IB4a PO2 (PAO2) must be calculated via the alveolar air
120. A. Distant or diminished breath sounds are demon- equation.
strated when sound transmission of the lungs or thorax
PAO2 =
is diminished. Distant breath sounds develop when the 1  FIO2
intensity of the sound is decreased. Airways that are
obstructed by either secretions or a foreign object are
(PB  PH2O)FIO2 – PaCO2 FIO2  ( R )
characterized by slow to no air movement. Thus, less
transmission of air sounds occurs. Hyperinflated air-
ways are associated with diminished breath sounds.
(
= 760 torr – 47 torr)1.0 – 42 torr 1.0 
1 – 1.0
0.8 )
Sound transmission is also decreased when air or liq-
= 713 torr – 42 torr
uid is in the intrapleural space.
= 671 torr
(1:313), (9:65), (16:173).
Now, the aforementioned shunt equation can be used:
IB7b Q̇ S (671 torr  560 torr)0.003 vol%/torr
121. B. COPD commonly causes hyperinflation. The chest =
radiography displays certain features that characterize Q̇ T 5.0 vol%(671torr560 torr)0.003 vol%/torr
hyperinflation, including 0.333 vol%
=
— large lung volumes; over-aeration 5.0 vol% 0.333 vol%
— increased retrosternal air space, viewed from a lat-
eral chest film 0.333 vol%
— depressed (flattened) hemidiaphragms =
5.33 vol%
— widened intercostal spaces
— horizontal appearing ribs = 0.06
— small, elongated heart (pulmonary emphysema)
— hyperlucency A Q̇ S/Q̇ T of 0.06, or 6.0%, is essentially normal, as the
normal anatomic shunt is 2.5% to 5.0%. Therefore, for
(1:414), (9:163). this patient, no treatment is indicated. Pulmonary func-
tion testing should be performed to evaluate the cause
IB9e of her dyspnea.
122. C. When a person complains of (1) excessive daytime (1:220–222), (6:148–151), (9:107–108, 261–262),
somnolence, (2) morning headaches upon awakening, (16:257, 329).
(3) decreased ability to concentrate, (4) loss of mem-
ory, (5) nocturnal enuresis, and (6) personality changes, IB7c
the person should have a sleep study performed to
evaluate for sleep apnea. 124. A. Following the insertion of a Swan-Ganz catheter
(PAC), a chest X-ray is used to assess the position of the
(1:554–557), (9:357–361), (16:300–302). PAC tip. Proper tip location is near the right mediastinal

Chapter 3: Clinical Data 165

 border. If the PAC tip is advanced too far into the pul- the left side is receiving less ventilation than the right.
monary artery, it needs to be withdrawn from that distal The patient has likely experienced slippage of the en-
position because (1) errors in cardiac output measure- dotracheal tube into the right mainstem bronchus.
ments can occur, (2) damage to the pulmonary vascula-
(1:308–309), (9:60), (15:440–441), (16:168–169).
ture can result, (3) spontaneous wedging can take place,
and (4) mixed venous blood samples are more likely to
be contaminated with arterial blood. IB7b
129. C. A radiographic finding called the silhouette sign
Having the PAC tip located in the main pulmonary helps determine whether a pulmonary infiltrate or con-
artery can be problematic. The extensive, turbulent solidation is contacting a heart border. Ordinarily, the
flow of blood in that region can produce significant density of the heart and surrounding lung tissue are
catheter-whip artifact. These whip artifacts would dis- different enough to enable the viewing of distinct heart
tort the pulmonary artery waveform. borders. If consolidation develops in lung tissue con-
(1:417–418), (9:34), (14:278–279). tacting any of the heart borders, the normal contrast
between the heart and surrounding lung tissue be-
IB8a comes lost. Consequently, the affected heart border is
blurred.
125. C. Epiglotittis causes a narrowing of the airway in the
supraglottic region. Ballooning of the hypopharynx The heart resides in the anterior aspect of the thorax.
and the thumb sign are characteristic radiographic fea- Therefore, a consolidation that obliterates any heart
tures seen on lateral neck X-rays of patients who have border must be present in the anterior-most segments
this condition. The thumb sign refers to the broadened of the lungs. Similarly, an infiltrate that does not
and swollen appearance of the epiglottis. Swelling of eliminate the contrast between the heart borders and
the aryepiglottic folds contributes to this condition. the surrounding lung tissue must be present in the
posterior-most segments. These segments do not con-
(1:162–163, 999, 1039–1040), (16:597–598, 983–984).
tact the heart.
IB1a So, if a chest X-ray indicates a blurred right heart border,
126. A. Pedal edema describes accumulation of fluid in the the pulmonary infiltrate must be located in the right mid-
lower (dependent) extremities. This phenomenon oc- dle lobe (RML). If the pneumonia were in the right up-
curs when hypoxia produces pulmonary vasoconstric- per lobe (RUL) or the right lower lobe (RLL), the right
tion, causing a chronic increase in the workload of the heart border would still be visible. The reason is both the
right ventricle. As right ventricular function decreases, RUL and RLL are behind (posterior to) the heart and are
the peripheral vessels engorge—and fluid leaks into not on the same plane as the heart. The RML is on the
the subcutaneous tissues. same plane as the heart; therefore, if the RML becomes
consolidated, the border between the right side of the
(1:318), (9:71, 242), (16:167). heart and the RML becomes invisible.
If the left heart border is obscured, the lingula is in-
IB1b
volved. Neither left anterior upper lobe nor left lower
127. C. Examination of a normal chest reveals a configura- lobe (LLL) pneumonia would obliterate the left heart
tion in which the transverse thoracic diameter is larger border, because all of these lobes are posterior to the
than the anteroposterior diameter by a ratio of 2:1. An heart.
anteroposterior diameter greater than the transverse di-
ameter is commonly associated with an obstructive (1:411), (9:159), (16:121).
pulmonary disorder that results from air trapping.
IB1a
(1:306–307), (9:56–57), (15:436–438), (16:163–165).
130. D. The chest wall features described in this question
IB2b are normal. An adult has a transverse chest wall diam-
128. B. Chest excursion should be equal and bilateral in the eter greater than that of the anteroposterior diameter.
mechanically ventilated patient. An acute change in At rest, a normal adult displays a consistent respiratory
chest excursion with no change in pulmonary status rate and rhythm. A minimum effort is associated with
should be evaluated immediately. Displacement of the inspiration, while exhalation is entirely passive. Men
endotracheal tube should be suspected with an acute generally exhibit diaphragmatic breathing, during
change in breath sounds. Given the retaping of the which the abdomen protrudes slightly outward on in-
tube, a decrease in breath sounds on the left, and chest spiration and inward on exhalation. Women typically
excursion on the left side, you should recognize that demonstrate a combination of external intercostal

166 Chapter 3: Clinical Data

 muscle usage and diaphragmatic effort. Consequently, IB9b
women generate more thoracic movement than males. 133. D. The minute ventilation (V̇E) of a subject is obtained
Inspiratory time is usually equal to expiratory time, by multiplying the person’s respiratory rate by the tidal
producing an I-E ratio of 1:1. The I-E ratio can also be volume. The tidal volume (VT) has two components:
1:2. Posteriorly, the ribs form a 45º-angle with the dead space volume (VD) and alveolar volume (VA).
spinal column. Therefore,
(1:306–308), (9:56–58), (16:163–166, 168). VT = VA  VD

IB7d The VD can be estimated according to a person’s ideal

body weight in pounds. Based on this guideline, the
131. B. The radiographic signs of atelectasis are as follows:
patient in this problem has an ideal body weight of 160
• localized increase radiographic density (can be a lbs. Therefore, this patient’s anatomic dead space vol-
lung segment, lobe, or the entire lung) ume is approximately 160 cc. Multiplying the VD by
• elevation of the diaphragm on the affected side (ip- the respiratory rate (f) provides the dead space ventila-
silateral diaphragm) tion or (V̇D). Thus,
• mediastinal shift toward the affected lung
VD  f = V̇D
• hilar displacement
• reduced size of rib interspaces over the affected This patient’s dead space ventilation is 160 cc times
lung the respiratory rate (f), or
• compensatory hyperinflation of adjacent segments,
V̇D = 160 cc  16 bpm = 2,560 L/min.
lobes, or the opposite lung
Because VT = VA  VD, the minute volume
Radiographic signs of the resolution of atelectasis in-
(V̇ E) equals V̇A  V̇D. That is,
dicate the reversal or lessening of these signs:
V̇E = V̇ A  V̇D
• increased radiolucency over the affected lung seg-
ment, lobe, or the entire lung Knowing both the V̇A and the V̇D, one can cal-
• normalization or reduced elevation of the di- culate the V̇ E. For example,
aphragm on the ipsilateral side
V̇E = 2,560 L/min.  4,000 L/min.
• lessening or absence of a previously recognized
mediastinal shift = 6,560 L/min.
• normal hilum position
(1:211–213), (17:26–28).
• increased size of rib interspaces over the affected
side
• decreased hyperinflation or normal inflation of
IB8b
areas adjacent to the atelectatic region. 134. B. The position of the diaphragm can be observed on a
chest radiograph. A number of pulmonary conditions
(9:160–162), (15: 853), (16:201–203, 507, 527). can cause elevation of the diaphragm on the affected
side. For example, atelectasis or pulmonary fibrosis
IB1a causes the intrapleural pressure on the affected side to
132. C. Digital clubbing (enlarged fingers and toes) is become lower. The lower intrapleural pressure can pull
called hypertrophic osteoarthropathy. This condition the hemidiaphragm on the affected side and cause it to
signifies cardiopulmonary disease. Digital clubbing elevate.
associated with pulmonary diseases appears as a pain-
Other lung problems, such as a tension pneumothorax
less enlargement of the terminal phalanges of the fin-
and pleural effusion, can cause the hemidiaphragm on
gers and toes.
the affected side to become depressed. If a neoplasm
Chronic pulmonary and cardiovascular conditions of- produces a significant obstruction of a larger airway,
ten associated with digital clubbing include the fol- the alveoli distal to the obstruction may collapse (i.e.,
lowing diseases: they might become atelectatic). In such a situation, the
hemidiaphragm on the affected side may elevate.
1. mesothelioma (~ 50% of patients)
2. bronchogenic carcinoma (1:925–926), (9:73–74), (16:167–168).
3. cystic fibrosis
4. bronchiectasis IB10e
5. congenital heart diseases (not all-inclusive) 135. D. Once a patient is diagnosed with obstructive sleep
(1:317–318), (7:580), (9:70–71), (15:674–675). apnea, a second polysomnography is performed to

Chapter 3: Clinical Data 167

 ascertain the level of CPAP that will eliminate the night sweats constitute part of the classical presenta-
snoring and the sleep apnea. The second sleep study tion of tuberculosis.
begins by attempting to confirm the diagnosis. No
(1:301), (9:30).
CPAP is used for the first hour to redocument the pres-
ence of obstructive sleep apnea. When the obstructive
sleep apnea has been reaffirmed, 5 cm H2O of CPAP is IB4a
initiated. The number of apneic episodes is counted. If 139. C. Stridor is a continuous, loud, high-pitched sound
snoring and apneic periods continue after 30 minutes, heard during auscultation of the larynx and trachea and
the CPAP level is increased to 7.5 cm H2O, i.e., 2.5 cm can be heard during either inspiration or exhalation.
H2O increments. This protocol is continued until the Stridor is also described as a harsh crowing or snoring
CPAP level terminates the sleep apnea and snoring is sound.
achieved. That CPAP level then becomes the therapeu- Vibrations resulting from the flow of air traveling at a
tic level for the patient for ensuing nights on home high velocity through a narrowed larynx or trachea
CPAP. cause stridor. A number of conditions can cause the
(1:557–563), (9:360–361), (16:301–303). airway lumen to narrow, including (1) mucosal edema,
(2) foreign object aspiration, (3) bronchospasm, (4)
IB1b airway inflammation, and (5) neoplasms.
136. C. Nasal flaring is the widening of the nostrils during Wheezes and rhonchi can be caused by the same con-
inspiration. The lateral aspects of the nostrils are called ditions that produce stridor. The quality of these two
the alae nasi. The alae nasi flare when a newborn at- adventitious breath sounds, however, differs from stri-
tempts to decrease airway resistance to accommodate dor. Wheezes are high-pitched, continuous sounds
a larger tidal volume and inspiratory air flow. Because heard over the lungs. Rhonchi are described as low-
newborns are obligate nosebreathers, nasal flaring may pitched, continuous sounds heard over the lungs.
increase minute ventilation through the nose by reduc-
Crackles are discontinuous sounds caused by the pres-
ing airway resistance.
ence of excessive secretions or fluid in the airways as
(9:202), (18:51, 90, 149). air flows through the lumen. These types of crackles
are frequently described as coarse crackles. Other
IB7a types of crackles include early inspiratory crackles and
137. C. Chest radiographs are commonly obtained to eval- late inspiratory crackles.
uate the position of a recently placed endotracheal Early inspiratory crackles are heard early in the inspi-
tube. The guideline for where the distal tip of the tube ratory phase and result from collapsed airways pop-
should be placed is 5 cm above the carina. The pa- ping open. Late inspiratory crackles occurring late in
tient’s neck position during this procedure is impor- the inspiratory phases are caused by collapsed alveoli
tant, because the distal end of the tube can move about opening suddenly.
4 cm from neck extension to neck flexion. The neck
should be maintained in a neutral position if possible (1:312–314), (9:64–66), (16:172–174).
when endotracheal tube placement is being radi-
ographically assessed. IB1c
140. D. Transillumination is a procedure used to quickly
Although placing this patient’s head in a neutral posi-
determine the presence of a pneumothorax in an infant
tion would likely cause the endotracheal tube (in this
or neonate. The examiner places a fiberoptic light
problem) to leave the right mainstem bronchus, it is
against the thorax. The skin of an infant or neonate is
not the solution to the problem. If the patient were to
so thin that the fiberoptic light shines through it. When
shift and move, the distal tip might once again enter
no pneumothorax is present, a halo of light forms
the right mainstem bronchus. So, the ultimate problem
around the area of skin in contact with the light source.
is not resolved. The tube should be withdrawn 2 to 3
When a pneumothorax or a pneumomediastinum is
cm and resecured. Withdrawing the tube 2 to 3 cm pro-
present, the entire air-filled region illuminates. The
vides sufficient room for the tube to “slide” as the pa-
light source is moved from side to side along the tho-
tient changes positions.
rax to identify the region of increased lucency.
(1:606), (9:151).
(9:205), (18:164).
IB1a
IB10a
138. A. Diaphoresis refers to profuse sweating which, when
141. D. A pulse oximeter is an excellent monitor of patient
it occurs at night, might soak the bed clothes. Such
oxygenation as long as the limitations of the device

168 Chapter 3: Clinical Data

 are recognized and heeded. The SaO2 (SpO2 from the blood to be aspirated into the sample. The balloon
pulse oximeter) and the arterial PO2 are related on the must be deflated, and a pulmonary artery tracing (Fig-
sigmoid-shaped oxyhemoglobin dissociation curve. ure 3-38) must be displayed before blood is aspirated.
An SpO2 of 90% and an SaO2 value of 90% corre-
When the PAC balloon tip is deflated and is in the pul-
spond with a PaO2 of 60 torr. SpO2 values less than
monary artery, a mixed venous blood sample can be
90% are associated with precipitously falling PaO2
obtained. Care must be taken, however, when collect-
values. SpO2 measurements greater than 90% and up
ing a mixed venous blood sample from the pulmonary
to around 100% generally correlate well with the
artery. After the balloon is deflated, and after the mix-
PaO2, because these saturations are on the flat part of
ture of flush solution and pulmonary artery blood is re-
the oxyhemoglobin dissociation curve. When the
moved from the line, the syringe must be aspirated
SpO2 reading is around 100%, however, the corre-
slowly. A rate of about 1 ml every 20 seconds should
sponding PaO2 cannot be determined. For example, a
be achieved. A sample volume of 2 to 5 cc is collected
PaO2 of 100 torr and a PaO2 of 600 torr will both in-
and is then discarded. A 2-ml sample is obtained (1
dicate the same SpO2; i.e., 100%. The pulse oximeter
ml/20 sec) for analysis of mixed venous blood.
is not sensitive enough to detect hyperoxia, nor can it
accurately represent the PaO2 when the SpO2 reads If the sample is aspirated into the syringe too quickly,
less than 90%. oxygenated blood from the pulmonary capillaries
might enter the syringe and contaminate the mixed ve-
According to the AARC Clinical Practice Guidelines
nous sample.
for Pulse Oximetry, pulse-oximeter limitations causing
false-negative results for hypoxemia or false-positive (1:345, 946–947), (9:265, 311), (14:273, 277, 278).
results for normoxemia or hyperoxemia might lead to
inappropriate treatment of the patient. IB7c
(AARC Clinical Practice Guidelines for Pulse 143. C. The tip of the CVP catheter must be located in the
Oximetry), (1:362–363,928), (9:267–268), (10:98–99), superior vena cava. When chest radiography is per-
(16:310, 401). formed to evaluate the catheter’s placement, however,
the tip of the catheter must be situated away from the
wall of the superior vena cava. If the CVP catheter’s tip
IB9c
rests against the wall of the superior vena cava, it can
142. B. The PAC waveform in Figure 3-37 signifies that the cause vessel-wall erosion. Continuous or repeated irri-
PAC is in the wedged position (10 to 12 torr). tation of the vessel wall by the stiff tip of the CVP cath-
A mixed venous blood sample must be obtained from eter can cause the wall of the superior vena cava to erode.
the pulmonary artery. When the PAC is in the wedged The CVP catheter might also be inserted into the right
position, the distal tip is in a pulmonary arteriole. If a atrium.
blood sample were collected with the PAC in this po-
sition, a greater likelihood would exist for capillary (1:416), (9:304), (14:232, 245), (16:220–221, 323).

15
mm Hg

10

0
Figure 3-37: PCWP waveform.

20
mm Hg

10

0
Figure 3-38: PAP waveform.

Chapter 3: Clinical Data 169

IB1a ing more anteriorly. Kyphoscoliosis is a combination
144. B. Cyanosis is a bluish coloration of the nail beds, of a posterior and a lateral curvature of the thoracic
skin, and mucous membranes. Cyanosis results when spine.
there is 5 grams percent or more of unsaturated hemo- (1:307, 442, 445), (7:21), (16:1026–1027), (19:699),
globin present in total circulation. Cyanosis can be (20:28,144–148, 327).
caused by hypoxemia, hypothermia, or decreased
perfusion. The most reliable method of identifying IB7e
cyanosis is inspection of the oral mucosa for bluish
146. B. Normally, the pulmonary vasculature in the upper
coloration. A decrease in oxyhemoglobin saturation or
lobes is essentially unnoticeable, and the pulmonary
arterial oxygen tension will not always result in
vessels in the lung bases are prominent. What accounts
cyanosis.
for this difference is the distribution of pulmonary per-
Patients who are anemic ([Hb] < 12 g%) frequently do fusion in an upright subject. Most of the pulmonary
not display cyanosis despite a low oxygen content. blood flow gravitates to the lower lobes, whereas less
Polycythemic patients, on the other hand, tend to ex- perfusion reaches the lung apices.
hibit cyanosis more readily because they are generally
In pulmonary edema, the pulmonary vasculature be-
already hypoxemic. Their hypoxemia is the cause of
comes engorged with blood because of the left ventri-
their polycythemia. Their inability to oxygenate this
cle’s inability to maintain normal cardiac output.
additional hemoglobin leads to their cyanosis. The mu-
Vascular pressures rise, and fluid transudes into the
cous membranes of the mouth offer the most reliable
pulmonary interstitium (and eventually into the alveo-
site for the evaluation of cyanosis, because they are
lar spaces). As this fluid congestion proceeds in the
least affected by perfusion, temperature, and skin pig-
lower lobes, pulmonary blood flow becomes redistrib-
mentation.
uted. As a result, the apical pulmonary vessels become
(1:318), (9:50, 58, 71, 112), (15:668). more perfused. These vessels are visible on a chest
X-ray. The Kerley B lines in the base of the right
IB1b hemithorax are lymphatic vessels that become fluid-
filled and observable on X-ray. The right-sided pleural
145. C. Pulmonary emphysema is a COPD that is defined
effusion is a consequence of a disruption of the vascu-
in anatomic terms as a nonreversible, abnormal en-
lar pressures related to Starling’s law of the capillaries.
largement of the alveoli distal to the terminal bronchi-
oles. The enlarged airspaces (alveoli) result from Once the pulmonary edema resolves, the distribution
alveolar septal (wall) destruction. of pulmonary blood flow normalizes; the pulmonary
vessels in the upper lobes are no longer visible on
Patients who have severe pulmonary emphysema ap- X-ray; the pulmonary vessels in the bases reappear as
pear to be in a continuous state of maximum inspira- edema fluid is reabsorbed; and the Kerley B lines dis-
tion. Their chest wall demonstrates an increased appear as the basal lymphatics empty. Lastly, the
anteroposterior (A-P) diameter. They exhibit a promi- pleural effusion resolves subsequent to the normaliz-
nent anterior chest, elevated ribs, costal margin flaring, ing of the vascular pressures.
and widening of the costal angles. These features
cause the patient’s chest to resemble a barrel; hence (1:512–513), (9:167).
the term barrel chest.
IB2b
During inspiration, the chest wall moves only slightly
because the lungs are in a hyperinflated state. To gain 147. C. The physical examination of the chest involves the
a mechanical advantage during inspiration, many em- following components: (1) inspection, (2) palpation,
physema patients brace their elbows on the arms of a (3) percussion, and (4) auscultation. Palpation involves
chair, or place their hands on a table and lean forward. touching the chest wall (thorax) to assess the functional
The expiratory phase is prolonged and accomplished status of the structures lying within the thorax. Palpa-
through pursed lips. Their I:E ratio can be 1:3, 1:4, 1:5, tion is performed to evaluate the following conditions:
or fewer. • vocal fremitus
• thoracic expansion
Pectus carinatum is a congenital chest-wall deformity
• subcutaneous emphysema
that is characterized by an abnormal forward projec-
• skin status
tion of the sternum. Pectus carinatum is also called pi-
geon chest. Pectus excavatum, also known as funnel When air leaks into subcutaneous tissues within the
chest, is another congenital chest-wall deformity thorax, the CRT feels fine bubbles under the skin. The
demonstrating a depressed sternum with the ribs on fine bubbles create a crackling sound and a crackling
each side of the depression (or saucerization), protrud- sensation. The sensation felt during the palpation of

170 Chapter 3: Clinical Data

 subcutaneous emphysema is called crepitus. Crepitus IB9a
resembles the sound of crumpling or rattling cello- 151. B. Because of the sigmoid shape of the oxyhemoglo-
phane. bin dissociation, a pulse oximeter does not detect hy-
(1:310, 483), (7:20–22, 582–584), (9:60, 230), peroxemia well. On the flat part of the oxyhemoglobin
(16:170, 207). dissociation curve, the SaO2 changes little in response
to wide changes in the PaO2. Furthermore, pulse
IB1b oximeters have a range of accuracy of ± 4% to 5%.
Therefore, the SaO2 can range from 96% to 100%. The
148. C. The barrel chest appearance is often associated with
PaO2 can be extremely high, however, yet the SpO2
pulmonary emphysema. Both chest diameters—trans-
reading can indicate a value of 90% and even as high
verse and anteroposterior—are approximately equal in
as 100%. There is no way of correlating the oxyhemo-
this obstructive process. The chest assumes the appear-
globin saturation and the PaO2 via pulse oximetry at
ance of permanent inspiration. During the ventilatory
high PaO2s.
cycle, the thorax moves up and down as a whole. Other
characteristics of the thorax that are often seen in con- (1:359–360), (4:286), (6:144–145), (9:96–99), (16:275,
junction with pulmonary emphysema include widened 310–312, 400–401).
intercostal spaces (horizontal ribs) and kyphosis.
(1:306–307), (9:56–57), (15:436–438), (16:163–165).
IB1a
152. A. Pooling of venous blood in the legs signifies that
IB10a the right ventricle is unable to maintain a cardiac out-
put to match the venous return. The consequence of
149. D. A number of factors cause the PETCO2 value to in-
venous blood accumulating in the lower extremities is
crease:
peripheral or pedal edema—fluid movement from the
• central respiratory depression systemic capillaries in the legs into interstium of the
• hypoventilation lower extremities. This increased interstitial fluid vol-
• untreated acute airway obstruction ume is what causes the legs to appear swollen. Fur-
• increased CO thermore, the degree of right-ventricular failure can be
• increased muscle contraction caused by seizures, assessed by the height to which the swelling rises. For
shivering, or pain example, swelling up to or beyond the knees indicates
• administration of NaHCO3 a much more severe right-ventricular failure than
• rebreathing of CO2 swelling only at the ankles.
• kinked or obstructed ventilator circuitry
The severity of the edema can also be quantified.
A number of factors cause the PETCO2 value to de- When the CRT places pressure with a finger on the
crease: swelling, the patient’s skin indents. As the CRT’s fin-
ger is removed from the patient’s skin, an indentation
• hyperventilation
remains. The longer the indentation persists, the more
• bronchospasm, excess secretions, and mucous
severe the edema. The pedal edema grading system
plugs
ranges from 1 (mild) to 4 (severe). A 1 grading
• cardiac arrest
represents a depression that disappears not immedi-
• pulmonary emboli
ately, but soon after pressure is applied. A 4 rating
• hypovolemia
indicates a deep impression that remains for a signifi-
• hyperthermia
cant period after pressure is removed.
• analgesia or sedation
• a leak in the ventilator circuit causing less expired (1:252), (9:71, 242), (16:167).
gas to reach the sensor
• an endotracheal tube lying in the hypopharynx IB10a
• an endotracheal tube resting in the right mainstem 153. B. The capnogram displayed shows a PETCO2 of 20
bronchus torr, which suggests that the patient is hyperventilat-
(1:363–366), (6:146–148), (16:313–315), (19:257–259). ing. If the patient had a normal ventilatory rate and
pattern, the PETCO2 would be around 40 torr and
IB1b would display a relatively flat middle phase.
150. B. Tenacious sputum is extremely sticky and viscous. Hyperthermia causes an increased PETCO2. An in-
Frothy means foamy. Fetid is foul-smelling. Copious creased cardiac output produces an increased PETCO2,
means present in large amounts. as does kinked or obstructed ventilator circuitry.
(1:299), (9:25–26), (15:622), (16:166). (1:363–366), (6:146–148), (16:313–315), (19:257–259).

Chapter 3: Clinical Data 171

IB4a viding the CO2 production (V̇CO2) by the fraction of
154. C. Increased lung tissue density causes bronchial alveolan CO2 (FACO2).
breath sounds to replace vesicular, or normal, sounds. V̇CO2
Conditions such as atelectasis and pneumonia are con- V̇A =
sistent with these changes in breath sounds. Air-filled FA CO2
lungs filter sound. Consolidated or collapsed regions If a patient has uneven distribution of ventilation, e.g.,
eliminate this sound-filtering effect. Consequently, in- severe pulmonary emphysema, the end-tidal PCO2
creased sounds are heard over large upper airways and (PETCO2) from capnography must not be used—be-
over airways leading to the consolidated lung. cause the PETCO2 does not equal the PACO2. In such
(1:313), (9:65), (16:172). cases, an arterial blood gas sample needs to be obtained
to measure the PaCO2. The formula then becomes
IB1b V̇CO2
155. D. Respiratory distress in an infant is frequently ac- V̇A = (0.863)
PACO2
companied by grunting, tachypnea, retractions, and
nasal flaring. Nasal flaring is unique to infants, be- The factor 0.863 converts from the concentration to the
cause they are obligate nose breathers. Flaring of the partial pressure and corrects the V̇CO2 measurement to
nostrils reflects an attempt to generate a larger tidal BTPS.
volume by increasing gas flow. (6:98–99).
(1:1030–1031), (18:148–149).
IB2b
IB1b 159. B. The physical examination of the chest involves the
156. D. General observation of the patient can identify pro- following components: (1) inspection, (2) palpation,
fuse sweating (diaphoresis), use of accessory muscles (3) percussion, and (4) auscultation. Palpation involves
of ventilation, and abnormal ventilatory patterns (de- touching the chest wall (thorax) to assess the functional
creased I:E ratio or paradoxical breathing). Vital signs status of the structures lying within the thorax. Palpa-
cannot be assessed by observation, because they re- tion is performed to evaluate the following conditions:
quire the use of equipment such as a stethoscope, ther-
mometer, and blood pressure cuff. Hypoxemia refers • vocal fremitus
to a decreased blood oxygen level which can only be • thoracic expansion
assessed by blood gas analysis or approximated by • subcutaneous emphysema
pulse oximetry. • skin status
• subcutaneous emphysema
(1:300–301), (9:50–52), (16:161–162).
Pneumonia patients frequently experience pleuritic
chest pain when taking a deep breath to cough, laugh,
IB4a
or sigh. These patients generally splint their chest wall
157. B. Crackles are discontinuous, high-pitched bubbling in order to diminish this pain. They also have fever,
or popping sounds. They are generally inspiratory tachycardia, and tachypnea and appear extremely ill.
sounds and usually clear following coughing. They are
considered to originate when collapsed alveoli pop Physical examination of the chest of a patient who has
open during inspiration, or when air flows through air- pneumonia usually reveals poor thoracic chest wall
ways or alveoli filled with secretions or fluid. Condi- movement, dullness to percussion, reduced breath
tions often associated with crackles include pulmonary sounds, and inspiratory crackles. The presence of con-
edema, pneumonia, atelectasis, chronic bronchitis, pul- solidation causes bronchial breath sounds and de-
monary emphysema, pulmonary fibrosis, and asthma. creased vocal fremitus over the involved area.

(1:314), (9:66), (16:174). The palpation is performed by having the patient re-
peat the words, “ninety-nine, ninety-nine, . . .” Vibra-
IB9c tions transmitted through the thorax and sensed by the
CRT’s hands are called tactile fremitus. Vibrations pro-
158. B. The determination of alveolar ventilation (V̇A) is
duced by the patient’s vocal cords during phonations
based on the excretion of CO2 from the lungs. A por-
and heard by the respiratory therapist are called vocal
tion of a patient’s exhaled volume is collected. The
fremitus.
volume of the exhaled CO2 is obtained by collecting
exhaled CO2 in a bag, balloon, or spirometer. The fol- (1:307–314, 428–429, 1041), (7:21), (9:58–60),
lowing formula can be used to calculate the V̇A, by di- (16:167–170), (20:69–70).

172 Chapter 3: Clinical Data

IB1b IB5a
160. C. An acute cough is characterized by sudden onset 164. D. A person who is experiencing illness, pain, or dis-
and a brief, severe course. Chronic cough is defined as comfort can exhibit a wide range of emotions, includ-
occurring daily for more than 8 weeks. Hacking cough ing severe anxiety, fear, depression, and anger. Pain
refers to a frequent dry cough or throat clearing. can interfere with auditory perception, the interpreta-
Paroxysmal cough describes periodic, prolonged, tion of auditory stimuli, and the response to such stim-
forceful episodes. uli. Medications can also affect mental and emotional
status and responses.
(1:298–299), (9:23–24), (15:664–665), (16:166).
(1:28–32).
IB3
161. C. A dull percussion note is indicative of fluid or con- IB4a
solidation in the airways. Resonance is the sound pro- 165. A. Rhonchi are continuous, deep, low-pitched rumbling
duced when a normal lung is percussed. Dull sounds heard via auscultation during exhalation. Rhon-
percussion notes indicate a decrease in resonance. chi results from bronchoconstriction, intraluminal or ex-
Lung conditions increasing the density of lung tissue, traluminal obstructions (neoplasms, for example), and
e.g., consolidation, neoplasma, or atelectasis, produce from thick secretions that partially obstruct the airways.
a dull percussion note over the affected region. The latter frequently disappear following coughing.
(1:310), (9:61), (15:441), (16:170). (1:313–314), (9:63–64), (16:173–174).

IB4a IB5b
162. B. A pneumothorax, endobronchial intubation, a mu- 166. A. Orthopnea is shortness of breath when lying
cous plug, and lobar atelectasis might result in unilat- supine. This condition is relieved when the patient sits
erally decreased or absent breath sounds. The fact that in a Fowlers or semi-Fowlers position. Orthopnea is
this finding is noted immediately after intubation sug- different from paroxysmal nocturnal dyspnea, which is
gests insertion of the endotracheal tube into the right episodic during the night. Orthopnea occurs as soon as
mainstem bronchus. If pulling the tube back slightly the patient reclines.
does not restore equal breath sounds, the patient should
(1:297, 541), (9:24–25), (15:671), (16:167).
be evaluated for a pneumothorax or mucous plugging.
Lobar atelectasis is an unlikely cause, because it usu-
ally develops insidiously rather than abruptly. IB7e
167. A. Abnormal pleural fluid, i.e., a pleural effusion, can
(1:597), (15:443, 833–835), (16:590–591). be a transudate or an exudate. Only a few clinical con-
ditions, such as CHF and atelectasis, cause a transu-
IB2b date to develop in the intrapleural space. On the other
hand, a variety of conditions produce an exudative
163. B. In a normal person, the thorax expands symmetri-
pleural effusion. These conditions include the follow-
cally during a deep inspiration. Palpation during the
ing pathologies:
chest physical examination enables the assessment of
the patient’s chest-wall expansion. • pulmonary embolism
• bacterial pneumonia
A number of pulmonary diseases influence the degree
• tuberculosis
to which the thorax expands. These conditions include
• bronchogenic carcinoma
the following:
• infectious lung disease
1. neuromuscular diseases
2. COPD
3. obesity } generally cause
bilateral reduction
of thoracic expansion
A pleural effusion can be present to varying degrees.
The radiographic and physical findings vary according
to the volume of the pleural effusion. A small volume
4. pleural effusion
5. lobar consolidation
6. atelectasis } often cause unilateral
reduction of thoracic
expansion but can be
bilateral
pleural effusion generally has the following radi-
ographic features:
• blunted costophrenic angle on the affected side
• partially obscured hemidiaphragm on the affected
Lung disorders can cause either bilateral or unilateral side
reduction of the thoracic expansion. The normal dis- • meniscus sign observed as fluid moves up the side of
tance for thoracic expansion is 3 to 5 cm. the chest wall, thereby forming a meniscus
(1:308–310), (7:583), (9:60), (16:168). (1:481), (9:168–170).

Chapter 3: Clinical Data 173

IB2b Intercostal (between the rib spaces) and sternal (above
168. D. The four components of the chest physical examina- and below the sternum) retractions indicate respiratory
tion are (1) inspection, (2) palpation, (3) percussion, and distress. Retractions are caused by the following con-
(4) auscultation. Palpation involves placing one’s hands ditions:
on the patient’s thorax to determine tracheal position, • decreased lung (pulmonary) compliance
muscle tone, tactile fremitus, vocal fremitus, chest-wall • increased lung (pulmonary) elastance
configuration, and symmetry of thoracic expansion. • severe upper-airway obstruction
When assessing the symmetry of chest-wall expan- • severe restrictive disease
sion, the CRT places his hands across each posterolat- Retractions can be caused by either obstructive or re-
eral aspect of the patient’s chest wall so that the strictive diseases.
thumbs meet at the posterior midline in the T8 to T10
vicinity. As the patient inhales deeply, the patient’s (1:307), (9:57), (15:436–437).
chest wall expands. The CRT’s hands move along with
the thoracic expansion, and in the process, each of the IB10b
CRT’s thumbs moves 3 to 5 cm from the posterior 171. B. Generally, the vital capacity is expected to be two to
midline. Normal chest-wall expansion is characterized three times the tidal volume (VT). When small differ-
by equal thumb tip movement of about 3 to 5 cm. ences exist between these two measurements, the pa-
tient is thought to have an inability to follow
Pulmonary disorders can cause either a bilateral re-
instructions. Guillain-Barré syndrome is a neuromus-
duction of thoracic expansion or a unilateral decrease
cular disease causing muscle weakness, which can in-
in chest-wall expansion. Conditions that commonly
volve the respiratory muscles and reduce the patient’s
appear with the bilateral reduction of chest-wall ex-
ventilatory reserve.
pansion include neuromuscular disease (Gullain-Barré
and myasthenia gravis) and COPD. Pulmonary condi- (1:374, 392), (9:129–130), (15:556).
tions that frequently manifest themselves as unilateral
thoracic reduction are pleural effusions (hemothorax, IB10d
empyema, and pneumothorax), atelectasis, and lobar 172. C. The 1987 American Thoracic Society (ATS) Stan-
consolidation. A pleural effusion, atelectasis, and lobar dardization of Spirometry guidelines define the best
consolidation can cause the bilateral reduction of curve as the FVC trial that has the largest sum of FEV1
chest-wall expansion if the condition occurs in both and FVC. The guidelines also specify that all volumes
lungs concurrently. and flow rates other than the FVC and FEV1 must be
(1:308–310), (7:583), (9:60), (16:168). determined on the best curve. Trial 3 has the largest
sum of FEV1 and FVC. Therefore, the FEF25%–75%
IB4a should come from Trial 3. Although Trial 4 reflects the
highest FEF25%–75%, that trial does not meet the crite-
169. D. Wheezes are produced when air flow is increased in
rion established by the ATS for selecting the appropri-
response to a narrowing of the airway lumen, resulting
ate FEF25%–75%.
in vibrations. The pitch of the wheezes relates to the
degree of compression, so the greater the constriction, (American Thoracic Society, Standardization of
the higher the pitch. As the patient fatigues, slower Spirometry 1987 update. Am Rev Respir Dis, 1987,
flow rates will occur. Therefore, disappearance of 136:1285–1298; Reprinted in Respiratory Care,
wheezing might indicate relief of bronchoconstriction 1987, 32:1039–1060).
(or paradoxically, the onset of ventilatory failure). In
the latter case, the breath sounds are significantly di- IB10f
minished. 173. B. The perfusion pressure of the tracheal mucosa is be-
(1:313–314), (9:65–66), (15:444), (16:173–174). tween 30 mm Hg on the arterial side and 18 mm Hg on
the venous side. According to Scanlan, the maximum
IB1b recommended levels of cuff pressures range from 20 to
25 mm Hg. This mm Hg pressure range corresponds to
170. D. When a patient’s WOB increases, a significant de-
a pressure range of 27 to 33 cm H2O. Naturally, a CRT
crease (more subatmospheric) in the intrapleural pressure
does not necessarily have to inflate the cuff to these
occurs during inspiration. The greater subatmospheric
pressures. Two methods are frequently recommended:
pressure generated within the intrapleural space pulls in
the skin overlying the thorax. The skin pulls inward be- 1. Minimal Occluding Volume (MOV): The CRT
tween the ribs above and below the sternum. The inward slowly inflates the cuff until he no longer hears
movements of the skin overlying the chest wall occur air escaping around the cuff at the PIP. Because
during inspiration and are called retractions. airways expand during a positive pressure

174 Chapter 3: Clinical Data

 breath, the pressure on the trachea during in- Methylene blue is sometimes added to a patient’s tube
halation is actually less than the pressure during feedings to check for the possiblity of aspiration. If
exhalation. Tracheal ischemia will increase as blue coloring of the patient’s tracheal secretions occurs
cuff pressure increases and as the number of during suctioning, this is an indication that the patient
positive pressure breaths decreases. has aspirated.
2. Minimal Leak Technique (MLT): Air is slowly (FOME-CUF® Users Manual, Bivona, Inc.),
injected into the cuff until the leak during PIP (1:609–610), (16:575–577).
stops. Once a seal is achieved, the CRT then re-
moves a small volume of air that will enable a IB4a
small amount of air to leak around the cuff dur- 174. D. Wheezes are high-pitched, continuous breath sounds
ing PIP. Since pharyngeal secretions are blown heard via auscultation during inspiration and/or exhala-
upward during the breath, however, the chances tion. Air moving through narrowed airways that vibrate
of aspiration are minimized (but not elimi- from the high velocity of the air flow produces wheez-
nated). Research indicates that the MLT might ing. This condition can occur during inspiration and/or
still result in excessively high pressures within exhalation. Airway caliber can be reduced by bron-
the cuff and consequently enable tracheal is- chospasm, mucosal edema, or aspirated foreign objects.
chemia to occur. Intracuff pressures should still
be routinely measured. (1:313–314), (9:65–66), (16:173–174).

The Lanz tube (Figure 3-39) and Kamen-Wilkinson foam IB7b

cuff (Figure 3-40) provide alternatives to standard cuff and
tube design. These tube designs lessen the likelihood of 175. D. When atelectasis (collapsed alveoli) occurs to a sig-
tracheal ischemia and damage. The Lanz tube, which uses nificant degree, it lowers the intrapleural pressure in
an external pressure-regulating valve and reservoir, limits the immediate area and causes the mediastinum and
the cuff pressure to a maximum of 18 mm Hg. trachea to be pulled toward the affected side. Radi-
ographically, atelectasis appears as densities or opaci-
fications. The hemidiaphragm on the affected side is
also generally elevated because of the decreased in-
trapleural pressure.
(1:773), (9:160–161), (15:604, 851–857), (16:527, 1117).
Plunger
IB9f
176. C. As a general recommendation, efforts should be
made to keep endotracheal tube cuff pressures as low
as possible. The average tracheal perfusion pressures
Air Syringe range from 30 mm Hg on the arterial side to 18 mm Hg
on the venous side. Maximum recommended cuff
pressures are 20 to 25 mm Hg. Cuff manometers are
To endotracheal tube cuff calibrated in cm H2O, so the acceptable upper-pressure
limit for cuff inflation would be from 27 to 33 cm H2O.
The lower the cuff pressure, the less chance there is of
External pressure-regulating causing damage to the tracheal wall. Lower pressures
valve and control balloon can increase the danger of aspiration, however. Some
authorities recommend a range of 25 to 30 cm H2O to
External cover
attempt to minimize tracheal damage and to lessen the
chance of aspiration. With patients who are receiving
mechanical ventilation, a leak might be allowed on in-
Figure 3-39: Lanz tube pressure regulating pilot balloon. spiration because the positive pressure will cause air to
be expelled from below the cuff, which might propel
The Kamen-Wilkinson (Bivona Fome-Cuf ®) uses at- secretions upward from the cuff.
mospheric pressure to fill the cuff. The pilot balloon
must remain open to the atmosphere to ensure that the (1:609–610), (15:836), (16:575–576).
cuff is adequately inflated. The Kamen-Wilkinson
foam cuff is deflated prior to intubation. Once the tube IB9c
is in place, the pilot tube is opened and the foam ex- 177. A. In the absence of lung disease, the primary stimulus
pands until it encounters the tracheal wall. to breathe is elevated carbon dioxide levels in the

Chapter 3: Clinical Data 175

 ch
Tra

e
Tub
A.

Cuff deflated
Cuff inflated

Tracheal wall Tracheal wall

B.
Figure 3-40: Kamen-Wilkinson foam cuff: (A) syringe must be used to
evacuate air from the cuff during tube insertion and removal. (B) Detach-
ment of the syringe from the pilot balloon enables atmospheric air to enter
and inflate the tube’s cuff.

blood. Carbon dioxide diffuses across the blood brain The goal in managing patients who have chronic bron-
barrier and combines with water to form carbonic acid. chitis is to maintain their PaO2 ranges between 50 and
Carbonic acid dissociates into a hydrogen (H) ion and 60 mm Hg. This PaO2 range will provide adequate de-
a bicarbonate ion. The resulting increased H ion con- livery of oxygen to the tissues without depressing ven-
centration reduces the pH of the cerebrospinal fluid, tilation. Although not as comfortable to wear as a nasal
stimulating the central chemoreceptors—which in cannula, a low concentration venturi mask (approxi-
turn, stimulates the person to breathe. The level of mately 24%) is preferred by many CRTs in order to
breathing that results lowers the PaCO2 levels to nor- ensure an accurate FIO2. At the same time, antibiotics,
mal, increasing the pH of the CSF and decreasing the diuretics, and other forms of treatment should be initi-
stimulus to the central chemoreceptors. ated by the physician to correct the underlying cause
of the patient’s acute respiratory failure.
During the progression of their disease, some people
who have chronic hypercarbia no longer breathe from The arterial blood gas is the only method that would
the stimulation of their central chemoreceptors by an enable the CRT to simultaneously track the patient’s
elevation of their PaCO2 and CSF PCO2 levels. In- oxygenation status as well as her ventilatory status (re-
stead, drops in their arterial PaO2s stimulate their pe- flected by her PaCO2). Although mixed venous moni-
ripheral chemoreceptors (carotid and aortic bodies) toring is helpful, this method is an extremely invasive
and cause them to breathe. Without this stimulation, procedure requiring the insertion of a PAC. An indica-
these persons would decrease their ventilatory drive tion that her hypoxic drive was suppressed by elevated
and could potentially lapse into a hypercapnic coma. blood levels of oxygen would be a worsening respira-

176 Chapter 3: Clinical Data

 tory acidosis and a blood level of oxygen that was body position-dependent. A 24-year-old person nor-
greater than 60 mm Hg. mally would be expected to have a P(A-a)O2 less than
5 torr while breathing room air and assuming a supine
(1:287, 288), (15:711–714), (16:130).
position. Encompassing 20 to 50 years of age, the
room air (supine) P(A-a)O2 ranges from about 5 torr to
IB4b 15 torr.
178. A. Depending on the lead, the ST segment will be ei-
ther depressed or elevated as a result of myocardial is- (1:256–257, 369), (3:186), (9:110, 261), (15:487–488).
chemia. A wide QRS complex is often seen in
electrolyte imbalances and in PVCs. Irregularly IB4a
spaced QRS complexes might occur with breathing. 181. C. Stridor is a high-pitched inspiratory sound often au-
Lengthened P-R intervals are consistent with first- dible without a stethoscope. This condition is associ-
degree block. ated with upper-airway obstruction and can signify a
life-threatening airway emergency.
(1:326), (9:184, 191–192).
(1:312), (9:66–67), (15:444), (16:982).
IB5b
179. C. The term orthopnea is defined as dyspnea occurring IB9c
when the patient reclines. Orthopnea is a frequent 182. C. The VD-VT ratio can be calculated via the following
symptom in patients who have congestive heart failure equation:
(left-ventricular failure). As the patient lies flat supine,
VD PACO2 – PĒ CO2
the left ventricle cannot accommodate the increased =
venous return and the greater right heart output. Blood VT PACO2
accumulates in the pulmonary vasculature, causing
The PaCO2 substitutes for the PACO2 ordinarily. So,
congestion and dypnea. The patient awakens breath-
the formula then becomes
less but often obtains relief when sitting up. Sitting up
reduces the venous return, lessening workload and pre- VD PaCO2 – PĒ CO2
load to the left ventricle. Platypnea is dyspnea that =
VT PaCO2
occurs in an upright position. Eupnea is normal breath-
ing. Dyspnea is labored, difficult breathing, but it is Furthermore, the PETCO2 value and PaCO2 often cor-
not specific enough regarding the situation in this relate well. Poor correlation between the PETCO2 and
question. PaCO2 values occurs in pulmonary diseases character-
ized by maldistribution of ventilation. COPD is a
(1:297–298), (9:23–25), (16:167).
chronic pulmonary disease having uneven distribution
of ventilation.
IB10c
180. B. When a patient has a shunt fraction (Q̇ S/Q̇ T) of 0.4, Therefore, when the VD/VT of a COPD patient is being
or a percent shunt of 40%, difficulty might be experi- measured, the PETCO2 must not be used in place of ei-
enced when trying to sustain spontaneous ventilation. ther the PACO2 or the PaCO2—because the PETCO2
Such a patient might require cardiopulmonary support. value poorly reflects the PACO2. The CRT should ob-
tain an arterial blood sample to measure the PaCO2.
Shunting is defined as pulmonary blood flow perfus- The PaCO2 must be used in the VD/VT determination
ing nonventilated alveoli. The consequence is no gas when the patient is known to have or is suspected of
exchange occurs, because the shunted pulmonary having abnormal distribution of ventilation.
blood does not make contact with alveolar air. If 100%
oxygen were administered to such a patient, the alveo- (1:212, 365–367), (6:98), (9:258–259).
lar PO2 would rise because of alveolar denitrogenation
(N2 washout), but the arterial PO2 would be virtually IB5b
unaffected. Blood flowing past the nonventilated alve- 183. D. A patient who complains of dyspnea while per-
oli would not benefit from the increased alveolar PO2. forming simple, everyday actions in and around the
Blood flowing past ventilated alveoli would not be home is said to have a decrease in activities of daily
able to correct the hypoxemia, because the hemoglo- living (ADL). One of the goals of a pulmonary and
bin in that blood is essentially 100% saturated and the cardiovascular rehabilitation program is to increase the
dissolved oxygen compartment cannot increase the patient’s ADL. Improving ADL improves the patient’s
CaO2 significantly. quality of life.
Therefore, the P(A-a)O2 for a patient who has a 0.4 One cannot assume that this patient has either obstruc-
shunt fraction would widen. The P(A-a)O2 is age and tive lung disease or cardiovascular disease, because a

Chapter 3: Clinical Data 177

 number of other diseases can cause breathlessness or IB9d
dyspnea. For example, interstitial lung diseases such 187. A. An FVC is obtained by having a subject inspire to
as asbestosis, sarcoidosis, and farmer’s lung can cause total lung capacity, then exhaling as rapidly, as force-
dyspnea. Interstitial lung disease can cause restrictive fully, and as completely as possible. The volume that is
and mixed lung disease. exhaled during this maneuver is the FVC. The volume
(1:297–298), (9:23–24), (16:167). that remains in the subject’s lungs is the Residual Vol-
ume (RV). The RV can be determined from body
IB10c plethysmography, 7-minute N2 washout, or He dilution
tests.
184. C. Normally, in a vertically oriented person, the lung
bases receive more blood flow than air flow; therefore, (1:380–383), (6:30–31), (9:134–135), (11:31–36),
the basal alveoli have low V̇/V̇s. The middle zone (16:226–229).
pretty much has equal pulmonary perfusion and alve-
olar ventilation. The V̇/V̇s there are essentially equal to IB5b
1.0. The apices are overventilated in relationship to 188. C. The term phlegm is generally understood by both
their perfusion and have high V̇/Q̇ ratios. laymen and clinicians as representing secretions from
When positive pressure mechanical ventilation is insti- the tracheobronchial tree. Phlegm that comes into con-
tuted, the lungs receive a greater-than-normal volume tact with oral, nasal, and sinus secretions becomes spu-
of air. That increased volume and increased (positive) tum.
pressure cause alveoli to inflate more than during spon- (1:299), (15:428–431).
taneous breathing. Therefore, the increased alveolar
ventilation increases the alveolar dead space, especially IB10c
in the apices. The VD/VT ratio usually increases when
positive pressure mechanical ventilation is instituted. 189. D. The pH is less than the normal range of 7.35 to 7.45.
A low pH indicates an acidosis. The arterial PCO2 is
Positive pressure mechanical ventilation does not in- greater than the normal range of 35 to 45 mm Hg and
crease a person’s anatomic dead space. The volume is controlled by the lungs. Because carbon dioxide
from the airway opening to (but excluding) the respi- combines with water in the plasma to form carbonic
ratory bronchioles constitutes anatomic dead space. acid, a high PaCO2 indicates respiratory acidosis.
(1:212, 237), (3:190), (16:132, 329–330). The HCO 3̄ value and the base excess are both greater
than their respective normal values, 22 to 26 mEq/liter
IB4a and 0 mEq/liter. Because the bicarbonate ion is a base,
185. C. Wheezes are described as high-pitched sounds au- a high HCO 3̄ value indicates a metabolic alkalosis. Be-
dible during either inspiration or exhalation. Wheezes cause the pH here (7.33) correlates with the PaCO2 (54
are more frequently heard during the expiratory phase. mm Hg), the primary problem in this case is respira-
The high-pitched, almost musical sound is generated tory acidosis. Some compensation has occurred, as ev-
by the flow of air passing through narrowed airways at idenced by a HCO 3̄ value elevated outside its normal
a high velocity. range. The pH has not returned to the normal range,
however; therefore, the compensation is partial, not
(1:313–314), (9:65–66), (15:444), (16:173–174). full.

IB9e (1:266–279), (9:212–214), (16:251, 265).

186. A. Respiratory impedance (inductive) plethysmogra-
phy enables the measurement of the subject’s tidal vol-
IB10b
ume, respiratory rate, chest-abdomen movement, and 190. C. One formula for determining the exhaled minute
end-expiratory thoracic gas volume (i.e., auto-PEEP). ventilation (V̇ E) is shown as follows:
Coiled wires, after having been sewn onto elastic volume expired  60 seconds/minute
bands in a sinusoidal fashion, are placed over the ab- V̇ E =
domen and chest wall. One band encompasses the collection time in seconds
chest wall, and the other encircles the abdomen.  BTPS factor
Two sets of waveforms are generated. The RC (rib cage) The BTPS factor would be included here if a volume-
and the AB (abdomen) waveform are displayed on an displacement spirometer at ambient temperature were
oscilloscope. Thoracoabdominal dyssynchrony can be used to measure the exhaled volume. Because a pneu-
detected by respiratory inductive plythysmography. motachometer held close to the patient’s airway was
(9:253–254), (21:232–234). used, BTPS factor in the calculation does not need to

178 Chapter 3: Clinical Data

 be included. The steps that follow demonstrate the cal- tion of the inspiratory time. Restrictive lung disease
culation of the exhaled minute ventilation: causes patients to breathe rapidly and shallowly. Pa-
tients who have atelectasis often assume this pattern.
STEP 1: Convert 2.75 minutes to seconds.
(1:307–308), (9:57–58), (16:164).
60 seconds
2.75 minutes  = 165 seconds
1 minute IB10c
STEP 2: Insert the known values into the equation. 194. A. Mixed venous PO2 (Pv̄O2) represents oxygen usage
by the entire body. Each organ and body part (arm, leg,
volume expired  60 seconds/minute liver, etc.) has its own particular oxygen needs and de-
V̇ E =
collection time in seconds mands. Depending on these needs and demands, the
venous blood leaving different organs or areas of the
32.7 liters  60 seconds/minute body differs in its PO2 value. The organs or areas that
=
165 seconds have a higher oxygen demand tend to have a lower ve-
nous PO2 than organs or regions that have a lower oxy-
= 11.9 liters/minute gen requirement.
(1:211), (9:129, 250), (15:1023). The normal range for the Pv̄O2 is 38 to 40 torr. Among
the conditions that produce a lower than normal Pv̄O2
IB4a are low cardiac output and anemia. On the other hand,
191. C. Rhonchi are low-pitched, continuous breath sounds factors such as left-to-right shunting, septic shock, in-
heard upon auscultation and will sometimes clear with creased cardiac output, and poor sampling techniques
a cough if the patient is able to mobilize secretions. are associated with an increased Pv̄O2 (i.e., greater
The presence of excessive secretions is often responsi- than 45 torr).
ble for rhonchi. Mucus vibrating or flapping in the
(3:103–106), (4:167, 214–216), (9:264–265), (16:255,
airstream in the lungs often produces rhonchi. Vesicu-
327–328).
lar breath sounds are normal sounds. Wheezes are
high-pitched, do not clear with coughing, and are con-
tinuous. Rales, or crackles, are wet, discontinuous IB4a
sounds. 195. D. Stridor is a continuous, high-pitched sound associ-
ated with upper-airway obstruction caused by inflam-
(1:313–14), (9:65–66), (15:444), (16:173–174). mation. This adventitious lung sound is heard in
epiglottitis, croup, and in inflammation of the upper
IB5a airway sometimes following extubation. Because stri-
192. D. There are many levels of consciousness. The most dor is associated with upper-airway obstruction, it can
basic level of consciousness is the natural response to be a life-threatening event. Patients who exhibit this
pain. Patients who are awake and are able to under- symptom must be monitored closely so that the appro-
stand questions might be able to state their name or to priate intervention can be instituted in a timely fashion
follow simple commands. Orientation to the fact that if the upper-airway obstruction worsens.
they are in the hospital in a specific city or state (ori-
(1:312), (9:66–67), (15:444), (16:982).
entation to place) is a higher level of consciousness.
The ability to perform simple math calculations indi-
cates the highest level of consciousness and brain IB10c
function. 196. A. In classical arterial blood gas interpretation, the
PaCO2 is the respiratory component, whereas the HCO 3̄
(1:28–31). is the metabolic measurement. Normal arterial blood
gas and acid-base values are illustrated in Table 3-24.
IB10b
Table 3-24: Normal arterial blood gas and acid-base
193. A. The normal I:E ratio for a spontaneously breathing ranges
adult is 1:1 or 1:2; i.e., inspiratory time is equal to ex-
piratory time (or exhalation is twice as long as inspira- PaO2 PaCO2 HCO 3̄
tion). (mm Hg) (mm Hg) pH (mEq/L)

Obstructive lung disease (e.g., COPD, asthma, and 80 to 100 35 to 45 7.35 to 7.45 22 to 26
cystic fibrosis) is characteristically associated with a
prolonged expiration time. I:E ratios can be 1:3 or
smaller. Acute upper-airway obstruction (e.g., epiglot- Both the PaCO2 and HCO 3̄ affect the pH. Increases
titis and laryngotracheobronchitis) causes prolonga- in the PaCO2 will decrease the pH and vice-versa.

Chapter 3: Clinical Data 179

 Increases in the HCO 3̄ will increase the pH. Conversely, Table 3-26
a decreased HCO 3̄ will decrease the pH. Mathemati-
Classification of
cally, the effect of the PaCO2 and the HCO 3̄ can be
Oxygen Status PaO2 Range (mm Hg)
calculated by using a modification of the Henderson-
Hasselbalch equation. hyperoxemia > 100
normoxemia 80 to 100
log HCO 3̄
pH = 6.1  mild hypoxemia 60 to 79
0.03  PaCO2 moderate hypoxemia 40 to 59
severe hypoxemia < 40
or
mEq/L (1:266–279), (9:212–214), (15:477–486), (16:251, 265).
6.1  log
(0.03 torr/mEq/L)(torr)
IB10d
Because an increase in the PaCO2 results in a decreased
pH, when the PaCO2 is greater than normal, the condi- 197. A. The 1987 American Thoracic Society (ATS) Stan-
tion is described as respiratory acidosis. The PaCO2 dardization of Spirometry guidelines specify that a
given in this problem represents this acid-base distur- minimum of three valid FVCs must be measured on
bance. In this arterial blood gas and acid-base analysis, each patient, and that the largest two valid measure-
the pH (7.39) is in the normal range because of a process ments be consistent within 5%. The largest FVC is
called compensation. The compensatory mechanism is 4.50 liters, and the second largest is 4.40 liters. To de-
an increase in HCO 3̄ (31 mEq/L) via renal function. The termine the percent difference between these two mea-
HCO 3̄ value, indicated on arterial blood gas reports, is surements, subtract the second-largest from the largest
calculated from the Henderson-Hasselbalch equation. and divide the difference by the largest.

A complete table for arterial blood gas and acid-base For example,
interpretation is outlined in Table 3-25. STEP 1: Subtract the second largest FVC (Trial 1)
Table 3-25: Arterial blood gas and acid-base interpretations from the largest FVC (Trial 3).
Trial 1 FVC
PCO2 HCO 3̄ B.E.
–Trial 3 FVC
Status pH (mm Hg) (mEq/L) (mEq/L)
FVC difference
Respiratory acidosis
uncompensated <7.35 >45 Normal Normal 4.50 liters
partially compensated <7.35 >45 >28 >+2  4.40 liters
compensated 7.35–7.40 >45 >28 >+2
Respiratory alkalosis 0.10 liter
uncompensated >7.45 <35 Normal Normal STEP 2: Divide the difference between the largest and
partially compensated >7.45 <35 <22 <–2
second-largest FVC by the largest FVC.
compensated 7.40–7.45 <35 <22 <–2
Metabolic acidosis FVC difference
uncompensated <7.35 Normal <22 <–2  100 = percent difference
partially compensated <7.35 <35 <22 <–2 largest FVC
compensated 7.35–7.40 <35 <22 <–2 0.10 liter
Metabolic alkalosis  100 = 2.2%
uncompensated >7.45 Normal >28 >+2 4.50 liters
partially compensated* >7.45 >45 >28 >+2
compensated* 7.41–7.45 >45 >28 >+2 Again, according to the 1987 ATS Standardization on
Combined respiratory Spirometry guidelines, the data presented here for the
and metabolic acidosis <7.35 >45 <22 <–2 FVC maneuver are reliable because the two largest
Combined respiratory FVC measurements vary by less than 5.0%.
and metabolic alkalosis >7.45 <35 >28 >+2
(American Thoracic Society, Standardization of
*In general, a partially compensated or compensated metabolic al- Spirometry 1987 update. Am Rev Respir Dis, 1987,
kalosis is rarely seen clinically because of the body’s mechanism to 136:1285–1298; Reprinted in Respiratory Care,
prevent hypoventilation. 1987, 32:1039–1060).
The normal range for the PaO2 is 80 to 100 mm Hg for
adults who are age 60 or younger. Values below this IB10c
range are classified as varying degrees of hypoxemia in 198. C. The fact that this patient’s ventilatory status was nor-
relation to a subject breathing room air. See Table 3-26. mal at the time the blood gas sample was obtained and

180 Chapter 3: Clinical Data

 the pulse oximeter saturation was normal should raise vascular markings represent the major vessels entering
suspicion about the blood-gas data. Aside from the point (pulmonary artery) and leaving (pulmonary veins) the
that the blood-gas values are consistent with those of ve- lungs. Vascular markings might be present elsewhere
nous blood, they are incongruent with the patient’s con- on the chest X-ray in pathologic conditions such as
dition. A patient who has a PaO2 of 43 torr is almost pulmonary edema and cor pulmonale.
severely hypoxemic and would be expected to have a
(1:404), (15:599), (16:188).
ventilatory rate higher than 16 breaths/minute, accom-
panied by an irregular ventilatory pattern.
IB3
The CRT should recommend that another arterial 203. C. To minimize interference imposed by the two scapu-
puncture procedure be performed. lae during percussion of the thorax during physical as-
(1:344), (15:534). sessment of the chest, the CRT should have the patient
raise both arms above the shoulders. This action causes
IB6 both scapulae to displace laterally, exposing more of the
posterior thorax for percussion. Percussing over the
199. B. When teaching children to perform a therapeutic
scapulae causes the vibrations to become damped.
procedure, the CRT must involve the children and have
them actively participate in the learning process. The (1:310), (9:61), (16:170).
terminology used must be understandable to the chil-
dren. They need the opportunity to be repetitious when IB6
practicing a skill, and they need to be aware of the ben- 204. B. Whenever a psychomotor skill is taught to a patient,
efits of the procedure. the CRT must demonstrate the task. The patient must
From a psychomotor standpoint, patients must believe then have the opportunity to perform as many return
that they have some degree of control over their learn- demonstrations as necessary. The number of return
ing. Parents do not necessarily need to be taught first. demonstrations necessary before the patient displays
Teaching the patient first enables the patient to develop proficiency will vary according to the sophistication of
self-esteem and a greater desire to learn. the task and the patient’s ability to understand and fol-
low instructions. The patient needs to practice all of
(1:1050–1051). the steps comprising the skill and perform them in the
appropriate sequence.
IB3
(1:1051).
200. A. The percussion sound produced over normal lung
tissues is described as resonant. Resonant sounds are
loud and low-pitched. Percussion performed over areas IB3
of the thorax overlying thickened pleural, atelectasis, 205. A. Percussion sounds are described as resonant, hy-
pleural effusion, and consolidation produces a dull per- perresonant, or dull. Resonant sounds are generated
cussion note. Dull percussion sounds are flat or soft, via percussion over normal chest wall areas. Hyper-
high-pitched, and short. Percussion over air trapped in resonant sounds are produced from percussing over
the lungs produces a hyperresonant sound. Hyperreso- lung regions that contain large volumes of air (e.g., a
nant sounds are loud, low-pitched, and lengthy. pneumothorax). Dull percussion sounds are character-
istics of percussion over areas of the thorax that have
(1:310), (9:61), (16:170). atelectasis, consolidation, or pleural effusion.

IB7e (1:310), (9:61–62).

201. B. Figure 3-8 illustrates a normal PA chest radiograph.
The costophrenic angle is identified by the number 8 IB3
on both sides of the chest X-ray. The costophrenic an- 206. C. Percussion of the chest wall should be performed on
gle is defined as the junction of the diaphragm and the one area of the lung on one side of the thorax. Then, the
chest wall. A pleural effusion (fluid in the intrapleural comparable area should be percussed on the opposite
space) causes blunting of the costophrenic angle in an side. Bony structures and female breasts must not be
upright projection. percussed, because these regions are not lung tissue.

(1:144, 406), (15:599), (16:188). (1:310), (9:61), (16:171).

IB7e IB6
202. C. In the normal chest radiograph presented here, vas- 207. C. Learning occurs in three domains: cognitive, affec-
cular markings can be observed near the hilum. These tive, and psychomotor. The cognitive domain concerns

Chapter 3: Clinical Data 181

 the process of learning factual information and con- 1189–1195), (AARC Clinical Practice Guidelines: In-
cepts. Higher cognitive learning includes analysis, ap- centive Spirometry, Respiratory Care, 1991; Vol. 36,
plication, interpretation, and synthesis. The affective No. 12, pages 1402–1405).
domain refers to the learner’s psyche. For example, a
patient’s attitude and motivation level influence learn- IC2c
ing. Learning to perform a task or a skill involves the 212. B. Following a systematic approach for interpreting ar-
psychomotor domain. terial blood-gas data is essential.
(1:1050). 1. Determine whether the pH is alkalemic or acidemic.
Because the pH is greater than 7.40, it is alkalemic.
IB6
208. C. The patient’s immediate concerns must first be ad- 2. Which measurement, PaCO2 or HCO 3̄, is consis-
dressed before learning can take place. In this situa- tent with the pH?
tion, the patient is in pain; therefore, the patient will The PaCO2 of 26 torr is consistent with the 7.56 pH.
likely be preoccupied with the pain and will be less Therefore, the primary acid-base problem is a respi-
motivated to learn. Alleviating the patient’s pain will ratory condition.
enable the patient to focus attention on the learning is-
sues being presented. 3. Evaluate the status of the remaining measurement,
i.e., the HCO 3̄ ion concentration. Is it within its
(1:1050–1051). normal range, or is it beyond its normal limits? The
normal range for the HCO 3̄ concentration is 22 to
IB8 26 mEq/L, or mmol/L. The HCO 3̄ value given in
209. B. A lateral neck X-ray will differentiate a supraglot- this problem is 23 mEq/L, which is within the nor-
tic (epiglottitis) airway narrowing from a subglottic mal range for the HCO 3̄ ion measurement. There-
(croup or LTB) airway obstruction. Once the narrow- fore, no compensation by the kidneys has occurred.
ing is viewed on the lateral neck X-ray, the CRT can The acid-base status can now be stated. This pa-
determine the presence of either condition. tient has an uncompensated respiratory alkalosis.
(15:395–396). The last aspect of arterial blood gas data to consider is
the PaO2, which is used to assess the patient’s oxy-
IB6 genation status. The patient in this problem is breath-
210. D. All three domains must be addressed when teaching ing room air and has a PaO2 of 107 torr. This situation
a patient. In this instance, the cognitive domain is used is possible. The patient here is hyperventilating (in-
to provide facts about the medication and the MDI. creased minute ventilation) and is increasing the PAO2.
The affective domain entails getting the patient to re- At the same time, his hyperventilation is causing his
alize the importance of the treatments to increase pa- PaCO2 to decrease below normal.
tient compliance. Also, this task involves getting the This patient has no hypoxemia. The stages of hypox-
patient to be an active participant in his own care. emia are shown in Table 3-27.
The psychomotor involves assembling, disassembling, Table 3-27
and cleaning the equipment. Coordinating the breath-
ing pattern with actuating the MDI is also essential. PaO2 Stage of Hypoxemia

(1:1052). 60–79 torr mild hypoxemia

40–59 torr moderate hypoxemia
ID1c Less than 40 torr severe hypoxemia
211. C. IPPB therapy is indicated when consolidation is
present and when the patient has an inspiratory capac- (1:272), (3:158–159), (4:134–138), (9:112–115),
ity (IC) of less than one-third of predicted. IPPB cre- (16:265–267).
ates positive pressure in the patient’s airways during
inspiration. The positive pressure delivered at the air- IC1a
way opening imposes a driving pressure between the 213. A. According to the AARC Clinical Practice Guideline
mouth and distal airways. The positive pressure that for Pulse Oximetry, a pulse oximeter is indicated for
reaches the distal airways helps to force open the pre- monitoring arterial oxygenation saturation during bron-
viously closed alveoli. choscopy. This device has the following limitations:
(AARC Clinical Practice Guidelines: Intermittent Pos- • motion artifacts
itive Pressure Breathing, 1993; Vol. 38, No. 12, pages • dysfunctional hemoglobin (HbCO and metHb)

182 Chapter 3: Clinical Data

 • intravascular dyes
• exposure of sensor to ambient light TLC
• low perfusion states
VC RV
• dark skin pigmentation 30
• nail polish

% N2
IV
• O2 saturation less than 83%
20
I III
(AARC Clinical Practice Guideline for Pulse Oximetry),
(1:361–362), (4:290–291), (9:267-268), (10:96–98). Segment for CV
10 ∆N2/liter
ID2 II 30% VC CC
214. A. This Guillain-Barré syndrome patient is rapidly and 0
progressively deteriorating in terms of his ventilatory 1.0 2.0 3.0 4.0 5.0 6.0
status. He is likely experiencing impending ventilatory VE (Liters)
failure. The muscle paralysis is gradually advancing to
the muscles of ventilation. As the MIP steadily de- Figure 3-41: Components and normal tracing of a single-
creases, the patient becomes less capable of maintain- breath nitrogen elimination test.
ing his spontaneous breathing. Therefore, intubating
and mechanically ventilating this patient now would This test also provides for the measurement of the
be appropriate. closing volume and closing capacity.
Other factors, such as arterial blood gas data and over- Phase I: anatomic dead space gas (100% O2)
all patient status, would of course also enter into the
clinical decision. No single criterion should be used to Phase II: anatomic dead space and alveolar gas mix-
determine the need for endotracheal intubation and ture
mechanical ventilation. The ability of this patient to Phase III: alveolar gas; alveolar plateau (basal and
continue spontaneous breathing, however, in view of mid-zone alveoli)
the deteriorating MIP values, and knowing that the pa-
tient has Guillain-Barré syndrome render high suspi- Phase IV: apical alveolar emptying predominantly
cion that ventilatory failure will ensue. (6:83–85), (11:108–115).
(1:545–546), (15:710), (16:1052).
ID1d
IC2b 217. C. CPAP is generally indicated for restrictive pul-
215. C. Because fetal hemoglobin has absorption charac- monary problems. Patients who undergo a thoracotomy
teristics almost the same as adult hemoglobin, SpO2 or upper-abdominal surgery experience a decreased
values correlate well with SaO2 measurements. Pulse FRC, because they are often confronted with post-
oximeters read falsely high in the presence of car- operative atelectasis and incisional pain. CPAP often
boxyhemoglobin (HbCO) and methemoglobin (metHb). results in a favorable outcome for these patients as the
Hyperbilirubinemia has no effect on the accuracy of a FRC increases in minutes following the application of
pulse oximater. the CPAP.
(1:361), (4:290), (10:97–98). Favorable responses to CPAP include
1) improved pulmonary mechanics
IC1b
— MIP more negative than –20 cm H2O after 20
216. C. When performing a single-breath nitrogen elimina- seconds
tion (SBN2) test, the patient must be instructed to ex- — VC greater than 10 cc/kg of ideal body weight
hale to residual volume before inspiring 100% O2 to (IBW)
total lung capacity. From that point, the patient exhales — VT capable of supporting normal work of
slowly and evenly to residual volume. The patient es- breathing (WOB)
sentially performs an SVC. Switching to 100% O2 at
residual volume enables the CRT to evaluate the even- 2) improved oxygenation
ness of the distribution of ventilation throughout the Before extubation is considered for this patient, the pa-
tracheobronchial tree as N2 is washed out from the tient’s FIO2 should be 0.30 or less, and the CPAP level
lungs from total lung capacity to residual volume. should be decreased in decrements of 2 to 3 cm H2O.
A normal SBN2 curve is displayed in Figure 3-41. As long as the FIO2 is 0.30 or less, CPAP can be

Chapter 3: Clinical Data 183

 discontinued at 5 cm H2O—assuming the patient has gions that have large time constants (time constant =
responded favorably at that level. compliance  airway resistance). Affording this addi-
tional time for air distribution is intended to enhance
(18:299–300).
gas exchange in otherwise poorly ventilated areas.

IC2a (1:845, 879), (16:686, 1052).

218. B. The modified Allen’s test is used to determine
whether ulnar arterial blood flow could perfuse the IC1c
hand if the radial artery were obstructed. A positive 221. A. Puncturing an artery distal to a surgical shunt of any
test indicates that ulnar flow could adequately perfuse kind (e.g., for dialysis) should not be done. The CRT
the hand. The test is performed by raising the hand should consider alternate puncture sites, namely, the
above the head, squeezing blood from the hand, oc- opposite arm. Performing arterial punctures through
cluding both radial and ulnar arteries, and then releas- any kind of lesion must also be avoided. If the pre-
ing only the ulnar after lowering the hand. A positive ferred site is infected or shows evidence of peripheral
test occurs when pink color returns to the hand, espe- vascular disease, the CRT should immediately con-
cially the thumb and forefinger, within 5 to 10 sec- sider an alternate puncture site.
onds. If the test is negative, an alternate puncture site (AARC Clinical Practice Guideline Sampling for Arterial
should be found. Blood Gas Analysis), (1:339–341), (4:10), (6:135),
(1:342), (9:107), (6:135). (16:270–271).

IC2b IC2c
219. A. Elevated bilirubin concentrations cause yellow dis- 222. A. Following a systematic approach for interpreting
coloration of the skin. This condition accounts for the arterial blood gas data is essential.
jaundiced appearance taken on by the skin of these pa- 1. Determine whether the pH is acidemic or alkalemic.
tients. Despite this discoloration, pulse oximetry read-
ings correlate well with measured SaO2 values. On the • normal pH: 7.35–7.45
other hand, co-oximetry measurements do not corre- • acidotic pH: < 7.35
late well with measured SaO2 values when bilirubin • alkalotic pH: > 7.45
concentrations are greater than 20 mg/dl. The pH in the problem is in the normal range.
Table 3-28 below lists normal bilirubin ranges for This situation might disguise the primary acid-base dis-
newborns. turbance. Because compensation can bring the pH
value into the normal range, the CRT should view the
Table 3-28
pH in terms of 7.40. In other words, if the pH is higher
Bilirubin than 7.40, a primary alkalosis should be suspected. On
Concentration Age the other hand, if the pH is lower than 7.40, a primary
acidosis should be considered. So, using this guideline,
1–6 mg/dl 24 hours the patient in this problem has a pH of 7.44, which is
6–8 mg/dl 48 hours
higher than 7.40. A primary alkalosis is suspected.
4–15 mg/dl 3–5 days
2. Which measurement—PaCO2 or HCO 3̄ —is consis-
tent with an alkalotic pH?
(1:361), (9:207, 268), (10:98).
A PaCO2 of 24 torr is consistent with an alkalotic
ID1d pH. The HCO 3̄ value is low, which is consistent
with an acidosis. Therefore, the primary acid-base
220. A. The PEEP that has been applied to this patient
problem is respiratory alkalosis.
might be inflating alveolar regions that are adequately
ventilated already, consequently producing a hyper- 3. Evaluate the status of the remaining measurement,
aerated condition in these regions. An inspiratory hold i.e., the HCO 3̄ concentration. The concentration is
is a mechanical means of sustaining lung inflation at well below the lower limit of normal (22–26
end-inspiration. The duration of the sustained inflation mEq/L) and is low because the kidneys have elimi-
customarily varies from one to two seconds. During nated HCO 3̄ ions to compensate for the decreased
this period, the delivered tidal volume is allowed to PaCO2. Renal compensation has occurred; hence the
spend more time in the lungs to become better distrib- return of the pH to within the normal range. The
uted through both lungs. The area of the lungs that are acid-base status can be described as a compensated
likely to benefit from this maneuver include those re- respiratory alkalosis.

184 Chapter 3: Clinical Data

 Now, consider the patient’s oxygenation status. Her IC1a
PaO2 is 37 torr. This PaO2 reflects severe hypoxemia. 226. A. Many COPD patients have an asthmatic component
The stages of hypoxemia are shown in Table 3-29. to their lung disease. To evaluate a patient’s respon-
siveness to a bronchodilator, a pre- and post-bron-
Table 3-29
chodilator spirometry (FVC maneuver) is performed.
PaO2 Stage of Hypoxemia The FEV1 is the measurement used to determine the
60–79 torr mild hypoxemia degree of reversibility in response to bronchodilator
40–59 torr moderate hypoxemia administration. If the FEV1 improves by 15% or more
Less than 40 torr severe hypoxemia following the administration of a bronchodilator, the
patient exhibits a favorable response to a bronchodila-
tor. The following formula is used to determine the
(1:272), (3:158–159), (4:134–138), (9:112–115), percent by which the FEV1 changes during a pre- and
(16:265–267). post-bronchodilator study.
post FEV1  FEV1
IC1b % change =  100
pre FEV1
223. A. The peak expiratory flow rate should be measured
after the patient has inspired maximally, i.e., total lung Based on the data presented with this question, the per-
capacity. A direct relationship exists between lung vol- cent change to bronchodilator therapy is as follows:
ume inspired and peak expiratory flow rate. The best
2.80 L  2.15 L
peak expiratory flow rate occurs when the patient ex- % change =  100
hales forcefully from total lung capacity. 2.15 L
(1:384), (6:45–47), (11:40). % change = 30%
This patient has shown significant improvement in
IC2a upper-airway air flow following the bronchodilator
224. A. Spirometric measurements of pulmonary function treatment. Significant improvement in air flow through
are often measured under Ambient Temperature and the small- and medium-size airway has also occurred
Pressure Saturated (ATPS) conditions and should be (approximately 20%). Therefore, this patient should be
converted to Body Temperature and Pressure Satu- prescribed a bronchodilator for treatment of his airway
rated (BTPS) conditions before comparing the results hyperreactivity.
with predicted normal values. The primary difference (AARC Clinical Practice Guidelines for Assessing Re-
between ATPS and BTPS conditions is the difference sponse to Bronchodilator Therapy at Point of Care),
between ambient temperature (22ºC to 26ºC) and (6:50–51), (9:136), (11:174–176).
body temperature (37ºC). According to Charles’ law,
gas volumes are directly related to temperature when ID1d
the pressure and mass of the gas are constant. Failure
227. B. A person who has inhaled carbon monoxide might
to convert an FVC from ATPS to BTPS conditions
be severely desaturated. Therefore, if he is sponta-
would result in spirometric data that are decreased 6%
neously breathing, he must be provided with an
to 9%.
oxygen-delivery device that is capable of administer-
(6:335–336), (11:5, 13, 462). ing high concentrations of oxygen. A nasal cannula
operating at 3 liters/minute is entirely inadequate to
achieve the therapeutic objectives in this situation. The
IC1c highest oxygen concentration possible with the nasal
225. C. Classification of PaO2 in the adult is summarized in cannula operating at 3 liters/minute (according to the
Table 3-30. low-flow oxygen delivery device criteria) is 32%. A
partial rebreathing mask set at 10 liters/minute, on the
Table 3-30: Classification of arterial Po2 other hand, can provide in excess of 80% oxygen. The
PaO2 (torr) Classification higher the oxygen concentration received by a CO poi-
soning victim, the shorter the half-life (t1/2) of CO. The
Greater than 100 hyperoxemia t1/2 of CO at sea level and at normal room temperature
80–100 normoxemia is about 5.3 hours. The t1/2 is decreased to about 1.5
60–79 mild hypoxemia hours when 100% oxygen is administered. The CO t1/2
40–59 moderate hypoxemia is further reduced under hyperbaric conditions.
Less than 40 severe hypoxemia
(1:764), (15:1107–1109), (16:1092).

Chapter 3: Clinical Data 185

IC1b adequately diagnostic of a pneumothorax to warrant
228. A. The purpose of performing a pre- and post- chest tube placement in cases where the infant is too
bronchodilator spirometry is to establish the presence unstable to obtain a chest radiograph.
or absence of reversible airway obstruction. Reversible (9:205), (18:164).
airway obstruction is said to exist if at least 15% im-
provement in the FEV1 occurs following the adminis- IC1b
tration of a bronchodilator.
231. A. When performing the single-breath CO diffusing
The formula for this determination is as follows: capacity test (DLCOSB), the subject is instructed to
perform an SVC (i.e., exhale to residual volume).
(post-bronchodilator FEV1)  (pre-bronchodilator FEV1)
From residual volume, she rapidly inspires the test gas
(pre-bronchodilator FEV1) (CO 0.3%, He 10%, and O2 21%) to total lung capac-
ity. Once total lung capacity is achieved, the subject is
 100 = % improvement
instructed to hold her breath for 10 seconds. After the
(AARC Clinical Practice Guidelines for Assessing Re- 10-second breath hold, she should exhale moderately
sponse to Bronchodilator Therapy, Respiratory Care, while a 500-cc sample of alveolar gas is collected. The
40:1300–1307, 1995), (6:49–50), (11:174–176). 500-cc sample is obtained after 750 to 1,000 cc of ex-
pirate have been discarded. The gas sample is ana-
IC2a lyzed.
229. D. Airway resistance is inversely proportional to the The purpose of the 0.3% CO is to measure the diffus-
flow rate, according to the equation Raw = P  V̇. If ing capacity, and the purpose of the 10% He is to help
bronchodilator therapy is effective in reducing bron- measure DLCO and the lung volume at which breath-
chospasm by relaxing the smooth muscles of the holding occurs. The alveolar volume (VA) measured
bronchi and bronchioles, thereby reducing airway re- under STPD conditions must be converted to BTPS
sistance, then the forced expiratory flow rates should conditions. The anatomic dead space is subtracted.
increase. Although both FEF25%–75% and FEV1 are The remainder is an estimate of the total lung capacity
forced expiratory flow rates, the FEV1 includes flow by a single-breath helium-equilibration technique.
through both bronchi and bronchioles; the FEV25%–75%
reflects the flow of gas only through the bronchioles. (1:386–388), (6:111–115), (11:126–149).
The FEV1 is a more encompassing measurement that
should be used to evaluate bronchodilator effective- ID1d
ness, regardless of the method of administration. The 232. D. Air leaks are caused by high intra-alveolar pressure
FEV1/FVC ratio, or FEV1%, is also important in dis- associated of insufflation with a large volume of air.
cerning an obstructive impairment from a restrictive The collection of extrapulmonary air in the interstitial
abnormality. space is called pulmonary interstitial emphysema
(PIE). PIE is a form of barotrauma common to preterm
(1:373), (6:49–51), (11:174–176).
infants who have noncompliant lungs and who are re-
ceiving mechanical ventilation. Reduction of PIP
ID1a mean airway pressure (P̄aw) and increasing the respi-
230. A. Transillumination provides rapid, safe, and reliable ratory rate has been shown to reduce barotrauma.
diagnosis of a pneumothorax in infants. A bright
fiberoptic light is applied to the chest wall in a dark- (18:165,489).
ened room. In the presence of a pneumothorax, the en-
tire hemithorax on the involved side will light up; that IC2c
finding is referred to as positive transillumination. 233. D. The normal PAO2-PaO2 gradient, or P(A-a)O2 gra-
With normal underlying lung tissue, only a small halo dient, ranges between 10 and 15 torr. Actually, the
of light surrounds the point of contact with the skin. P(A-a)O2 gradient is dependent on the person’s age
Care must be taken to avoid cutaneous burns from the and body position. The P(A-a)O2 gradient widens with
light source. The procedure should be performed by an age.
experienced practitioner who is skilled in interpreting
In most circumstances, however, when a person
transillumination. The area of transillumination can be
breathes 100% O2, the P(A-a)O2 decreases because
misleading, particularly if a pneumomediastinum or
more O2 in the alveoli diffuses across the alveolar-
pulmonary interstitial emphysema is present. Applying
capillary membrane and into the dissolved state as the
the light to the mid-axillary line, rather than the ante-
PaO2. In some conditions, most notably those that are
rior chest wall, can be helpful. Positive transillumina-
characterized as shunt-producing diseases (e.g., pneu-
tion by a skilled practitioner is considered to be
monia) increasing the FIO2 widens the P(A-a)O2 gra-

186 Chapter 3: Clinical Data

 dient. When the P(A-a)O2 gradient widens, it is some- its use in monitoring the oxygenation of smoke-
times clinically useful to quantify the amount of shunt. inhalation victims is completely inappropriate. A tran-
scutaneous PO2 monitor only measures the PO2 of the
(1:234), (16:256, 370).
skin capillaries. PaO2 values of smoke inhalation vic-
tims are not influenced by CO inhalation. Only the
ID1d oxygen combining with hemoglobin is affected. The
234. C. An increase in the intracranial pressure warrants the SaO2 obtained from an arterial blood sample is a cal-
application of mechanical hyperventilation. The hy- culated value and not a measured value.
perventilation causes the arterial PCO2 to decrease,
which in turn reduces cerebral perfusion via cerebral (1:353, 358–363), (3:333–345), (4:282–293),
vasoconstriction. In situations such as these, the arter- (6:141–146), (10:95–99,102–104).
ial PCO2 is generally maintained between 25 and 35
torr. IC1b
237. C. When performing a maximum voluntary ventilation
(15:1101).
maneuver, the subject should be instructed to breathe
as rapidly and as deeply as possible at a volume
IC2d greater than the subject’s tidal volume and less than his
235. C. The pressure-volume loop illustrates two curves vital capacity. This pattern must be maintained for 12
(Figure 3-42). One curve, A-B-C, is the inspiratory to 15 seconds at a ventilatory rate of 70 to 120
limb of the loop. The other curve, C-D-A, is the expi- breaths/min.
ratory limb. The point along the loop that represents
the tidal volume is point C. Figure 3-43 is a tracing obtained from an MVV ma-
neuver.
(1:386–386), (6:47–49), (11:51–54), (16:235).
VT C
D
IC2a
238. A. A restrictive lung-disease pattern of pulmonary
ion
Volume (ml)

lat

function data would include lung volumes less than

ha

on

80% of the predicted normal values. In this case, the

Ex

ati

FVC and TLC are lung volumes that are reduced be-
pir
Ins

low 80% predicted. Patients who have restrictive lung

disease have small vital capacities and may exhale up
B to 100% of their vital capacities in one second. Their
A PIP FEV1/FVC ratio is usually normal and can be some-
times as high as 100%.
Pressure (cm H2O)
(6:36), (11:121).
Figure 3-42: Pressure-volume loop. Curve A-B-C is the in-
spiratory limb of the loop; curve C-D-A is the expiratory seg-
ment of the loop. The horizontal dotted line from point C to ID1b
the y-axis indicates the VT. The vertical dotted line extending 239. D. Erroneous orders or confusing orders are an occa-
from point C to the x-axis represents the PIP.
sional problem in any health-care setting. To handle
By dropping a line from point C to the x-axis, one can this problem, all respiratory care department policy
obtain the PIP. and procedure manuals should contain a procedure to
follow in this circumstance. The policy and procedure
(1:199), (10:48), (15:88).
manual should be approved by the department medical
director. Safe and appropriate courses of action should
IC1c be outlined. CRTs are responsible for identifying con-
236. C. Because smoke-inhalation victims likely have some fusing or erroneous orders and handling them accord-
degree of carbon monoxide (CO) poisoning, they have ing to departmental policy.
an unknown carboxyhemoglobin concentration. The
analytical device that is most suitable for measuring the (1:6, 35), (16:39–50).
arterial oxygen saturation (SaO2) is a co-oximeter. A
co-oximeter is a spectrophotometer capable of simulta- IC1b
neously measuring four types of hemoglobin: oxyhe- 240. C. In normal subjects, the FVC equals the SVC. The
moglobin, deoxyhemoglobin, carboxyhemoglobin, and FVC and SVC can actually differ by 200 cc. When the
methemoglobin. A pulse oximeter cannot differentiate SVC exceeds the FVC by more than 200 cc, one of
carboxyhemoglobin from oxyhemoglobin. Therefore, two situations can account for this disparity: (1) the

Chapter 3: Clinical Data 187

 1 sec. at 10mm/sec.
10

7 8
7
6 50
6 Breath-by-Breath Tracing

Volume (liters)
Liters

5 5 40

Second Maneuver
Volume for the 12
4 4

Accumulated
30
3

(liters)
3
2 Accumulated Volume 20
2 1 Tracing

0 10
1 5 10 15
Time (seconds)
0
Figure 3-44: Normal volume-time MVV tracing, showing
Figure 3-43: Normal volume-time MVV tracing. breath-by-breath tracing and accumulated volume tracing.

patient’s effort was submaximal, or (2) airway ob- ID1c

struction is present. 242. B. This condition can be deceiving. The absorption of
(1:376), (6:36), (9:130), (11:43). more drugs might worsen the situation quickly. There-
fore, endotracheal intubation and mechanical ventila-
IC2a tion are indicated. Arterial blood gas data reveal that
this patient is experiencing an uncompensated respira-
241. B. The MVV test requires strong coaching before and
tory acidosis, that is, acute ventilatory failure. The
during the maneuver. The patient is expected to
blood gas and acid-base condition resulted from CNS
breathe as rapidly and as deeply as possible for at least
depression caused by the drug abuse. Ventilatory sup-
72 seconds. The breathing pattern performed is similar
port would be expected to improve the patient’s oxy-
to the pattern of a person who is running vigorously.
genation status. Nasal CPAP is contraindicated in
Once an MVV value has been obtained, judgment can conditions associated with CO2 retention (hypoventi-
be made about the patient’s degree of effort. This lation).
judgment or evaluation can be made by multiplying
(15:707–718).
the subject’s actual FEV1 by 35. This calculation is
shown as follows:
actual FEV1  35 = estimated MVV
3.50 L  35 = 122.5 L
IC2a

This patient’s MVV is estimated to be 122.5 L/sec. 243. C. During a seven-minute N2 washout test, a subject
The MVV tracing (Figure 3-44) shows that the pa- breathes 100% oxygen—and in the process, washes
tient’s actual MVV is 120 L/sec. out N2 from the lungs. As the patient breathes 100%
oxygen, breath-by-breath exhaled N2 analysis is per-
The MVV from this tracing is determined by multi- formed, and a progressive decrease in the log of the
plying the 12-second volume, i.e., 24 liters, by 5, or 5 percent of exhaled N2 occurs. In the normal tracing
 24 L = 120 L/sec. Because the estimated MVV and shown in Figure 3-45, one can see that the % exhaled
the actual MVV are essentially equal, the patient’s ef- N2 declines incrementally with each breath, beginning
fort can be evaluated as maximal. with about 79% N2 and ending with approximately
(6:47–49), (11:51–54). 1.5% N2.

188 Chapter 3: Clinical Data

 100% number of cardiovascular and ventilatory responses.
80% The following physiologic responses are among the in-
dices of an adverse reaction to the application of PEEP:

Log of % No.
10% • decreased cardiac output
• decreased blood pressure
• increased heart rate
1% • increased arterial-venous oxygen content difference
[C(a-v̄)O2]
• decreased pulmonary compliance
0.1% • decreased arterial PO2
The elevated intrathoracic pressure might reduce the
venous return, thereby decreasing the cardiac output
Volume Expired and blood pressure. As the cardiac output and blood
pressure fall, the heart rate increases. An increased
Figure 3-45: Normal seven-minute N2 washout curve. C(a-v̄)O2 may signify hypovolemia, decreased venous
This test must be performed in a closed system to pre- return, or a decreased cardiac output. A decreased pul-
vent room air from entering the system during the pro- monary compliance (static compliance) indicates that
cedure and contaminating the composition of the the alveoli are overly distended and have moved up on
system gas. If room air enters the system through a the compliance curve, resulting in less volume change
leak in the breathing circuitry or around the patient’s for the increased pressure change (V/P = C). With
mouth, a nitrogen spike will appear on the tracing decreased gas exchange and decreased cardiac output,
(Figure 3-46). the arterial PO2 falls.
(1:879–880), (9:283–284, 317), (15:724–729, 909–911).
N2
80
ID1a
245. D. The volume-time tracing (refer to Figure 3-47) pro-
60 vides normal pulmonary function data associated with
the patient who is described here.
Nitrogen spike
40 6

5 FVC 5.0 L
Volume (liters)

Air leak
20 detection 4 FEV1 4.0 L

3 FEV1
FEV1% 80%

x 100 = FEV1%
0 FVC
0 2 4 6 8 2
4.0 L
Volume 1 x 100 = 80%
5.0 L
Figure 3-46: Seven-minute N2 washout curve showing an
N2 spike, characterizing an air leak during the procedure. 1 2 3 4 5
A gradual decline in the % exhaled N2 will be dis- Time (seconds)
played from the point at which the air leak (N2 spike)
Figure 3-47: Volume-time spirogram showing FEV1 and
occurred. Whenever an air leak takes place, the test FVC measurements.
must be terminated and begun again after the recali-
bration of the equipment and after the re-equilibration The FVC is 5.0 liters, while the FEV1 is 4.0 liters. The
of the patient’s lungs with room air. FEV1/FVC ratio is 80%, i.e.,
(1:377–379), (6:86–87), (11:87–90), (16:238–239). FEV1
 100 = FEV1%
FVC
ID1b
244. B. When PEEP is instituted, the patient’s functional 4.0 liters
 100 = 80%
residual capacity increases. In the process, the mean in- 5.0 liters
trathoracic pressure rises, and with it a variety of dele-
The normal range for the FEV1% for this size patient
terious effects are possible. The application of PEEP
(70 cm and 150 lbs) is 70% to 83%. Similarly, the
must always be accompanied by the monitoring of a

Chapter 3: Clinical Data 189

 FEV2% ranges from 84% to 93%, and the FEV3% nor- ID1b
mally lies between 94% and 97%. 248. D. Postural drainage therapy is indicated when a diag-
(6:37–39), (9:134–135), (11:38–42). nosis of bronchiectasis has been made. Patients who
have bronchiectasis have airways that are abnormally
IC2a dilated, which causes pooling of secretions; conse-
246. D. After exhaling to RV, the patient inhales a breath of quently, these patients expectorate large amounts of
100% oxygen to total lung capacity. From TLC, the sputum. Postural drainage therapy mobilizes bronchial
patient exhales as slowly and as evenly as possible secretions, resulting in improved ventilation to the ar-
back to RV. In the process of performing this test, a eas previously completely or partially blocked with
normal person generally produces the single-breath ni- mucus. These patients are positioned to allow gravity
trogen elimination curve shown in Figure 3-48. to drain retained secretions from the lungs. Additional
measures used to enhance the mobilization of secre-
tions include percussion and vibration, as well as
30 coughing. Bronchiectatic patients should be closely

Total Lung Capacity

monitored during this procedure because of the
Exhaled % N2

IV
possibility of deleterious effects, such as vomiting and
20 III aspiration, hypoxemia, and other potentially life-
threatening complications. The patients who have uni-
10 CV lateral lung disease (the patient in this scenario) should
II
RV be placed on their side with the involved lung upper-
I most and the uninvolved lung gravity dependent. Oxy-
0 gen therapy with pulse-oximetry monitoring would
1 2 3 4 5 6
also be indicated for these patients during the postural
VC drainage therapy.
CC
(AARC Clinical Practice Guidelines, Postural Drainage
Figure 3-48: Normal single-breath N2 elimination curve
(VC = vital capacity, CC = closing capacity, CV = closing Therapy, Respiratory Care 1991; Vol. 36, pages
volume, RV = residual volume). 1418–1426), (1:796–801), (16:511–515).
Maldistribution caused by obstructive airflow disease
generates a curve where the beginning of phase IV and
ID1a
the end of phase III are virtually indistinguishable. If 249. A. Occupational lung diseases are often grouped under
the obstruction is severe enough, phases II, III, and IV the name pneumoconiosis. Specific names are given to
may appear continuous (with no distinct difference diseases associated with particular substances. Ship-
among these three phases). builders are exposed to asbestos and can develop as-
bestosis. Silicosis refers to silica, or quartz, exposure.
(6:83–86), (11:160–164). Byssinosis, or brown lung, comes from cotton dust.
Bagassosis is related to sugar cane.
ID1a
(9:20–21), (15:367–368).
247. A. Symmetry of chest excursion is assessed via palpa-
tion. Chest expansion is decreased unilaterally in those
diseases that commonly affect only one lung. When
ID1c
palpating the chest for symmetry, the CRT will note a 250. C. This patient has bilateral pneumonia, which creates
decreased movement on the affected side producing capillary shunt units and units characterized by perfu-
asymmetrical chest movement. sion in excess of ventilation (shunt effect or venous
admixture). This intrapulmonary shunting is the phys-
Therefore, lobar pneumonia, lobar atelectasis, pleural iologic basis for this patient’s hypoxemia. The hypox-
effusion, and pneumothorax can all result in asymmet- emia is responsible for the tachycardia, hypertension,
rical chest movement. Additionally, a pneumothorax and hyperventilation occurring with this patient.
and pleural effusion can, if large enough, cause the
mediastinum to shift to the unaffected side. Lobar at- A portion of the intrapulmonary shunt is amenable to
electasis (and in some cases, lobar pneumonia) cause oxygen therapy. That component is characterized by
the mediastinum to shift toward the affected side. perfusion in excess of ventilation. These shunt effect
regions still enable ventilation to occur, thereby in-
(1:308–309), (9:58–60), (15:440–441), (16:167–170). creasing the patient’s fraction of inspired oxygen

190 Chapter 3: Clinical Data

(FIO2). This increase will correct the hypoxemia ac- the oxygen administered will lower the heart rate, the
cording to the portion of the intrapulmonary shunt blood pressure, and the ventilatory rate as the hypox-
comprising venous admixture units. emia becomes corrected.
Therefore, if a significant portion of this patient’s in- (1:221, 233), (3:86, 90, 97), (9:261–262), (15:347).
trapulmonary shunt is comprised of shunt effect units,

Chapter 3: Clinical Data 191

 References
1. Scanlan, C., Spearman, C., and Sheldon, R., Egan’s 12. Koff, P., Eitzman, D., and New, J., Neonatal and Pedi-
Fundamentals of Respiratory Care, 7th ed., Mosby- atric Respiratory Care, 2nd ed., Mosby-Year Book,
Year Book, Inc., St. Louis, MO, 1999. Inc., St. Louis, MO, 1993.
2. Kacmarek, R., Mack, C., and Dimas, S., The Essentials 13. Branson, R., Hess, D., and Chatburn, R., Respiratory
of Respiratory Care, 3rd ed., Mosby-Year Book, Inc., Care Equipment, J. B. Lippincott, Co., Philadelphia,
St. Louis, 1990. PA, 1995.
3. Shapiro, B., Peruzzi, W., and Kozlowska-Templin, R., 14. Darovic, G., Hemodynamic Monitoring: Invasive and
Clinical Applications of Blood Gases, 5th ed., Mosby- Noninvasive Clinical Application, 2nd ed., W. B. Saun-
Year Book, Inc., St. Louis, MO, 1994. ders Company, Philadelphia, PA, 1995.
4. Malley, W., Clinical Blood Gases: Application and Non- 15. Pierson, D., and Kacmarek, R., Foundations of Respira-
invasive Alternatives, W. B. Saunders Co., Philadel- tory Care, Churchill Livingston, Inc., New York, 1992.
phia, PA, 1990. 16. Burton, et al., Respiratory Care: A Guide to Clinical
5. White, G., Equipment Theory for Respiratory Care, 3rd Practice, 4th ed., Lippincott-Raven Publishers,
ed., Delmar Publishers, Inc., Albany, NY, 1999. Philadelphia, PA, 1997.
6. Ruppel, G., Manual of Pulmonary Function Testing, 7th 17. Wojciechowski, W., Respiratory Care Sciences: An In-
ed., Mosby-Year Book, Inc., St. Louis, MO, 1998. tegrated Approach, 3rd ed., Delmar Publishers, Inc.,
7. Barnes, T., Core Textbook of Respiratory Care Practice, Albany, NY, 1999.
2nd ed., Mosby-Year Book, Inc., St. Louis, MO, 1994. 18. Aloan, C., Respiratory Care of the Newborn and Child,
8. Rau, J., Respiratory Care Pharmacology, 5th ed., 2nd ed., Lippincott-Raven Publishers, Philadelphia,
Mosby-Year Book, Inc., St. Louis, MO, 1998. PA, 1997.
9. Wilkins, R., Sheldon, R., and Krider, S., Clinical As- 19. Dantzker, D., MacIntyre, N., and Bakow, E., Compre-
sessment in Respiratory Care, 3rd ed., Mosby-Year hensive Respiratory Care, W. B. Saunders Company,
Book, Inc., St. Louis, MO, 1995. Philadelphia, PA, 1998.
10. Pilbeam, S., Mechanical Ventilation: Physiological and 20. Farzan, S., and Farzan, D., A Concise Handbook of Res-
Clnical Applications, 3rd ed., Mosby-Year Book, Inc., piratory Diseases, 4th ed., Appleton & Lange, Stam-
St. Louis, MO, 1998. ford, CT, 1997.
11. Madama, V., Pulmonary Function Testing and Cari-
opulmonary Stress Testing, 2nd ed., Delmar Publish-
ers, Inc., Albany, NY, 1998.

192 Chapter 3: Clinical Data

 CHAPTER 4 EQUIPMENT

PURPOSE: The intention of this chapter is to assist you in working through the 90 NBRC matrix items concern-
ing equipment on the Entry-Level Examination Matrix. This chapter is comprised of 211 items intended to assess
your understanding and comprehension of subject matter contained in the equipment portion of the Entry-Level Ex-
amination for Certified Respiratory Therapists. In this chapter, you will be required to answer questions regarding
the following activities:

IIA. selecting and obtaining equipment and assuring cleanliness of equipment appropriate to the respiratory
care plan
IIB. assembling, checking for proper function, identifying malfunctions of equipment, and taking action to
correct malfunctions of equipment

The NBRC Entry-Level Examination is divided into three content areas:

I. Clinical Data
II. Equipment
III. Therapeutic Procedures
Table 4-1 outlines the number of questions in the Equipment content area and the number of questions in this area
according to the levels of complexity.
Table 4-1

Number of Questions Level of Complexity

Content Area in Content Area Recall Application Analysis

II. Equipment 36 14 22 0

Although the Equipment section of the Entry-Level Examination contains 90 matrix items, only 36 questions from
the 90 matrix items will appear on the examination. Furthermore, be aware that numerous matrix items in this con-
tent area encompass multiple competencies. For example, matrix designation IIB2a (1) refers taking action to cor-
rect malfunctions of oxygen administration devices. This matrix item encompasses the (1) nasal cannula, (2) simple
mask, (3) reservoir mask (partial rebreathing and nonrebreathing), (4) face tent, (5) transtracheal oxygen catheter,
and (6) oxygen conserving cannulas. Notice that matrix designation IIB2a (1) refers to six different aspects of tak-
ing action to correct malfunctions of oxygen-administration devices. Many other matrix designations in this section
and in the other two sections of the Entry-Level Examination encompass multiple components.
Chapter Four is sequenced according to the order of the matrix designations listed in the NBRC Entry-Level Ex-
amination Matrix. To begin, you will be presented with questions relating to the matrix heading IIA. Matrix head-
ing IIA asks you to perform the following tasks.
IIA—Select, obtain, and assure equipment cleanliness
Then, you will be presented with questions concerning matrix heading IIB. Matrix heading IIB expects you to
conduct the following activities.
IIB—Assemble and check for equipment function; identify and take action to correct equipment mal-
functions; and perform quality control

193
This strategy will help you organize your personal study plan. Without an organized approach, your efforts will be
haphazard and chaotic. Additionally, you will squander valuable time and effort reading unnecessary and irrelevant
subject matter. Following this plan will help you identify strengths and weaknesses concerning equipment.
After finishing each section (IIA and IIB) in this chapter, stop to assess your results by (1) studying the analyses
(located later in this chapter), (2) reading references, and (3) reviewing the relevant NBRC Entry-Level Examina-
tion matrix items.
After the questions on each section in this chapter, you will find the relevant portion of the Entry-Level Exami-
nation Matrix. Be sure to thoroughly review these matrix items because the NBRC develops the Entry-Level Ex-
amination based on these items.
Make sure you allot yourself adequate time (1) to answer the questions, (2) to review the analyses, (3) to use the
references, as necessary, and (4) to thoroughly study the Entry-Level matrix items. Although the sections in this
chapter will be in sequence (i.e., IIA and IIB), the questions within each section will be randomized.
Table 4-2 indicates each content area within the Equipment section and the number of matrix items in each section.
Table 4-2

Equipment Number of
Subcategories Matrix Items

IIA 32
IIB 58
TOTAL 90

The answer sheet for this chapter is located on the following pages. Remember, many matrix items have multi-
ple components. Therefore, certain matrix designations will be repeated but will pertain to different concepts. Make
sure you read and study the matrix designations because the NBRC Entry-Level Examination is based on the
Entry-Level Examination Matrix.

194 Chapter 4: Equipment

 Equipment Answer Sheet
DIRECTIONS: Darken the space under the selected answer.

A B C D A B C D
1. ❏ ❏ ❏ ❏ 25. ❏ ❏ ❏ ❏
2. ❏ ❏ ❏ ❏ 26. ❏ ❏ ❏ ❏
3. ❏ ❏ ❏ ❏ 27. ❏ ❏ ❏ ❏
4. ❏ ❏ ❏ ❏ 28. ❏ ❏ ❏ ❏
5. ❏ ❏ ❏ ❏ 29. ❏ ❏ ❏ ❏
6. ❏ ❏ ❏ ❏ 30. ❏ ❏ ❏ ❏
7. ❏ ❏ ❏ ❏ 31. ❏ ❏ ❏ ❏
8. ❏ ❏ ❏ ❏ 32. ❏ ❏ ❏ ❏
9. ❏ ❏ ❏ ❏ 33. ❏ ❏ ❏ ❏
10. ❏ ❏ ❏ ❏ 34. ❏ ❏ ❏ ❏
11. ❏ ❏ ❏ ❏ 35. ❏ ❏ ❏ ❏
12. ❏ ❏ ❏ ❏ 36. ❏ ❏ ❏ ❏
13. ❏ ❏ ❏ ❏ 37. ❏ ❏ ❏ ❏
14. ❏ ❏ ❏ ❏ 38. ❏ ❏ ❏ ❏
15. ❏ ❏ ❏ ❏ 39. ❏ ❏ ❏ ❏
16. ❏ ❏ ❏ ❏ 40. ❏ ❏ ❏ ❏
17. ❏ ❏ ❏ ❏ 41. ❏ ❏ ❏ ❏
18. ❏ ❏ ❏ ❏ 42. ❏ ❏ ❏ ❏
19. ❏ ❏ ❏ ❏ 43. ❏ ❏ ❏ ❏
20. ❏ ❏ ❏ ❏ 44. ❏ ❏ ❏ ❏
21. ❏ ❏ ❏ ❏ 45. ❏ ❏ ❏ ❏
22. ❏ ❏ ❏ ❏ 46. ❏ ❏ ❏ ❏
23. ❏ ❏ ❏ ❏ 47. ❏ ❏ ❏ ❏
24. ❏ ❏ ❏ ❏ 48. ❏ ❏ ❏ ❏

Chapter 4: Equipment 195

 A B C D A B C D
49. ❏ ❏ ❏ ❏ 77. ❏ ❏ ❏ ❏
50. ❏ ❏ ❏ ❏ 78. ❏ ❏ ❏ ❏
51. ❏ ❏ ❏ ❏ 79. ❏ ❏ ❏ ❏
52. ❏ ❏ ❏ ❏ 80. ❏ ❏ ❏ ❏
53. ❏ ❏ ❏ ❏ 81. ❏ ❏ ❏ ❏
54. ❏ ❏ ❏ ❏ 82. ❏ ❏ ❏ ❏
55. ❏ ❏ ❏ ❏ 83. ❏ ❏ ❏ ❏
56. ❏ ❏ ❏ ❏ 84. ❏ ❏ ❏ ❏
57. ❏ ❏ ❏ ❏ 85. ❏ ❏ ❏ ❏
58. ❏ ❏ ❏ ❏ 86. ❏ ❏ ❏ ❏
59. ❏ ❏ ❏ ❏ 87. ❏ ❏ ❏ ❏
60. ❏ ❏ ❏ ❏ 88. ❏ ❏ ❏ ❏
61. ❏ ❏ ❏ ❏ 89. ❏ ❏ ❏ ❏
62. ❏ ❏ ❏ ❏ 90. ❏ ❏ ❏ ❏
63. ❏ ❏ ❏ ❏ 91. ❏ ❏ ❏ ❏
64. ❏ ❏ ❏ ❏ 92. ❏ ❏ ❏ ❏
65. ❏ ❏ ❏ ❏ 93. ❏ ❏ ❏ ❏
66. ❏ ❏ ❏ ❏ 94. ❏ ❏ ❏ ❏
67. ❏ ❏ ❏ ❏ 95. ❏ ❏ ❏ ❏
68. ❏ ❏ ❏ ❏ 96. ❏ ❏ ❏ ❏
69. ❏ ❏ ❏ ❏ 97. ❏ ❏ ❏ ❏
70. ❏ ❏ ❏ ❏ 98. ❏ ❏ ❏ ❏
71. ❏ ❏ ❏ ❏ 99. ❏ ❏ ❏ ❏
72. ❏ ❏ ❏ ❏ 100. ❏ ❏ ❏ ❏
73. ❏ ❏ ❏ ❏ 101. ❏ ❏ ❏ ❏
74. ❏ ❏ ❏ ❏ 102. ❏ ❏ ❏ ❏
75. ❏ ❏ ❏ ❏ 103. ❏ ❏ ❏ ❏
76. ❏ ❏ ❏ ❏ 104. ❏ ❏ ❏ ❏

196 Chapter 4: Equipment

105. ❏ ❏ ❏ ❏ 134. ❏ ❏ ❏ ❏
106. ❏ ❏ ❏ ❏ 135. ❏ ❏ ❏ ❏
107. ❏ ❏ ❏ ❏ 136. ❏ ❏ ❏ ❏
108. ❏ ❏ ❏ ❏ 137. ❏ ❏ ❏ ❏
109. ❏ ❏ ❏ ❏ 138. ❏ ❏ ❏ ❏
110. ❏ ❏ ❏ ❏ 139. ❏ ❏ ❏ ❏
111. ❏ ❏ ❏ ❏ 140. ❏ ❏ ❏ ❏
112. ❏ ❏ ❏ ❏ 141. ❏ ❏ ❏ ❏
113. ❏ ❏ ❏ ❏ 142. ❏ ❏ ❏ ❏
114. ❏ ❏ ❏ ❏ 143. ❏ ❏ ❏ ❏
115. ❏ ❏ ❏ ❏ 144. ❏ ❏ ❏ ❏
116. ❏ ❏ ❏ ❏ 145. ❏ ❏ ❏ ❏
117. ❏ ❏ ❏ ❏ 146. ❏ ❏ ❏ ❏
118. ❏ ❏ ❏ ❏ 147. ❏ ❏ ❏ ❏
119. ❏ ❏ ❏ ❏ 148. ❏ ❏ ❏ ❏
120. ❏ ❏ ❏ ❏ 149. ❏ ❏ ❏ ❏
121. ❏ ❏ ❏ ❏ 150. ❏ ❏ ❏ ❏
122. ❏ ❏ ❏ ❏ 151. ❏ ❏ ❏ ❏
123. ❏ ❏ ❏ ❏ 152. ❏ ❏ ❏ ❏
124. ❏ ❏ ❏ ❏ 153. ❏ ❏ ❏ ❏
125. ❏ ❏ ❏ ❏ 154. ❏ ❏ ❏ ❏
126. ❏ ❏ ❏ ❏ 155. ❏ ❏ ❏ ❏
127. ❏ ❏ ❏ ❏ 156. ❏ ❏ ❏ ❏
128. ❏ ❏ ❏ ❏ 157. ❏ ❏ ❏ ❏
129. ❏ ❏ ❏ ❏ 158. ❏ ❏ ❏ ❏
130. ❏ ❏ ❏ ❏ 159. ❏ ❏ ❏ ❏
131. ❏ ❏ ❏ ❏ 160. ❏ ❏ ❏ ❏
132. ❏ ❏ ❏ ❏ 161. ❏ ❏ ❏ ❏
133. ❏ ❏ ❏ ❏ 162. ❏ ❏ ❏ ❏

Chapter 4: Equipment 197

 A B C D A B C D
163. ❏ ❏ ❏ ❏ 188. ❏ ❏ ❏ ❏
164. ❏ ❏ ❏ ❏ 189. ❏ ❏ ❏ ❏
165. ❏ ❏ ❏ ❏ 190. ❏ ❏ ❏ ❏
166. ❏ ❏ ❏ ❏ 191. ❏ ❏ ❏ ❏
167. ❏ ❏ ❏ ❏ 192. ❏ ❏ ❏ ❏
168. ❏ ❏ ❏ ❏ 193. ❏ ❏ ❏ ❏
169. ❏ ❏ ❏ ❏ 194. ❏ ❏ ❏ ❏
170. ❏ ❏ ❏ ❏ 195. ❏ ❏ ❏ ❏
171. ❏ ❏ ❏ ❏ 196. ❏ ❏ ❏ ❏
172. ❏ ❏ ❏ ❏ 197. ❏ ❏ ❏ ❏
173. ❏ ❏ ❏ ❏ 198. ❏ ❏ ❏ ❏
174. ❏ ❏ ❏ ❏ 199. ❏ ❏ ❏ ❏
175. ❏ ❏ ❏ ❏ 200. ❏ ❏ ❏ ❏
176. ❏ ❏ ❏ ❏ 201. ❏ ❏ ❏ ❏
177. ❏ ❏ ❏ ❏ 202. ❏ ❏ ❏ ❏
178. ❏ ❏ ❏ ❏ 203. ❏ ❏ ❏ ❏
179. ❏ ❏ ❏ ❏ 204. ❏ ❏ ❏ ❏
180. ❏ ❏ ❏ ❏ 205. ❏ ❏ ❏ ❏
181. ❏ ❏ ❏ ❏ 206. ❏ ❏ ❏ ❏
182. ❏ ❏ ❏ ❏ 207. ❏ ❏ ❏ ❏
183. ❏ ❏ ❏ ❏ 208. ❏ ❏ ❏ ❏
184. ❏ ❏ ❏ ❏ 209. ❏ ❏ ❏ ❏
185. ❏ ❏ ❏ ❏ 210. ❏ ❏ ❏ ❏
186. ❏ ❏ ❏ ❏ 211. ❏ ❏ ❏ ❏
187. ❏ ❏ ❏ ❏

198 Chapter 4: Equipment

 Equipment Assessment
IIA—Select, obtain and assure equipment cleanliness.

NOTE: This portion of the equipment assessment will contain 111 questions and analyses. Upon completing
this portion, you should stop to evaluate your performance on the 111 questions pertaining to matrix
section IIA. Please refer to the NBRC Entry-Level Examination Matrix designations located at the end
of the IIA content area of the Equipment section to assist you with evaluating your performance on the
test items in this section.
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the one that is best in each case, then blacken the corresponding space on the
answer sheet found in the front of this chapter. Good luck.

IIA1a(2) IIA1b
1. A COPD patient enters the emergency department 4. Which of the following nebulizers would administer
with the following room air blood gas data. long-term, high-aerosol output while producing parti-
cles of 5µ or less via an aerosol tent?
PaO2 45 torr
PaCO2 75 torr A. ultrasonic nebulizer
pH 7.30 B. Babington nebulizer
HCO 3̄ 36 mEq/L C. medication nebulizer
B.E. 12 mEq/L D. centrifugal nebulizer
The patient has an irregular pattern of breathing with a
ventilatory rate of 22 breaths/min. Which of the following IIA1a(1)
oxygen-delivery devices is most appropriate at this time? 5. A patient has been prescribed home oxygen therapy
via a nasal cannula. The patient is concerned about the
A. air entrainment mask cost of the oxygen and other home-health interven-
B. partial rebreathing mask tions. Which of the following oxygen-delivery devices
C. nonrebreathing mask would conserve the use of oxygen and reduce the over-
D. simple mask all cost of this therapeutic intervention?

IIA1h(3) I. a lanyard-style nasal cannula

II. a lariat-style nasal cannula
2. The CRT is obtaining an E cylinder of oxygen for a pa-
III. a pendant-style nasal cannula
tient who is to be transported from her room to the pul-
IV. a nasal mask
monary function lab. Which of the following types of
connections should the CRT use to secure the regula- A. IV only
tor to the E cylinder? B. III only
C. I, III only
A. Diameter-Index Safety System
D. I, II, III, IV
B. American Standard Safety System
C. Pin-Index Safety System
D. Quick Connect System IIA1r
6. The CRT receives an order to administer a 2% solution
IIA2 of Virazole to an 18-month-old patient who has bron-
chiolitis. Which of the following devices should be
3. The CRT is responsible for selecting an antimicrobial
used to administer this drug?
agent to be used for hand washing. Which of the fol-
lowing agents is appropriate? A. large-volume nebulizer
B. small-volume nebulizer
A. iodophor
C. small-particle aerosol generator
B. soap and water
D. jet nebulizer
C. hexachlorophene
D. glutaraldehyde

Chapter 4: Equipment 199

IIA1f(4) A. I, III only
7. A CRT is preparing to orally intubate a neonate. Which B. II only
of the following equipment would be appropriate? C. II, IV only
D. I, IV only
I. curved laryngoscope blade
II. stethoscope IIA1e(1)
III. oxygen tubing
11. A ventilator that operates directly from a rotary-driven
IV. Magill forceps
piston will produce which of the following flow pat-
A. I only terns?
B. II, IV only
A. sine wave
C. I, II, IV only
B. square wave
D. II, III, IV only
C. accelerating flow
D. decelerating flow
IIA1h(5)
8. Which of the following types of analyzers is appropri- IIA1g
ate to use when a carbon monoxide lung diffusion ca-
12. Oropharyngeal secretions are best removed by using
pacity study is performed?
which of the following catheters?
A. infrared absorption analyzer
A. Yankauer suction tip
B. emission spectroscopy analyzer
B. Trach Care closed suction system
C. thermal conductivity analyzer
C. Coudé suction catheter
D. gas chromatography analyzer
D. modified whistle-tip catheter
IIA1a(1)
IIA1i(1)
9. Which of the following oxygen devices can deliver an
13. When assembling an IPPB circuit for patient use, a
FIO2 higher than expected if the patient’s tidal volume
tube carrying gas during inspiration from the IPPB de-
decreases?
vice must be attached to the exhalation valve for the
I. Venturi mask purpose of
II. simple oxygen mask
A. providing a reservoir to maintain a consistent
III. nasal cannula
FIO2.
IV. partial rebreather mask
B. ensuring the delivery of inspiratory gas flow to the
V. aerosol mask
patient.
A. I, II, IV, V only C. ensuring operation of the inspiratory nebulizer.
B. II, IV, V only D. permitting exhalation before the ensuing inspira-
C. I, IV, V only tion.
D. II, III, IV only
IIA2
IIA1c 14. Which of the following sterilization techniques would
10. The CRT is called to the CCU to set up a 28% aerosol require additional aeration time for equipment after
mask on a patient. The only nebulizers available have sterilization and before its use with patients?
variable FIO2 settings ranging from 0.35 to 1.00. The
A. steam autoclave
CRT decides to set up a titration system operating the
B. ethylene oxide
nebulizer on air at the 35% entrainment setting at 10
C. Cidex
liters/minute and titrating in 6 liters/minute of oxygen.
D. dry heat
Which of the following statements concerning this
system is (are) correct?
IIA1h(5)
I. This arrangement will create a low-flow system. 15. The CRT is in need of an oxygen analyzer that can per-
II. The total flow rate will be approximately 62 to 66 form rapid gas analysis during exercise testing. Which
liters/minute. of the following oxygen analyzers would be suitable
III. The nebulizer should be changed to the 100% set- for this purpose?
ting at 10 liters/minute and should titrate in 1
liter/minute of oxygen. I. galvanic
IV. The nebulizer driving the aerosol should be at- II. paramagnetic
tached to the oxygen flow meter while titrating air III. polargraphic
to the system. IV. zirconium

200 Chapter 4: Equipment

 A. I, III only pH 7.30
B. II, IV only HCO ¯3 34 mEq/L
C. III, IV only B.E. 10 mEq/L
D. I, II only
The patient complains of increased shortness of
breath. The physician wants to initiate ventilatory sup-
IIA1d port. Which of the following forms of mechanical ven-
16. During the resuscitation of a neonate, the CRT at- tilatory assistance would be appropriate for the CRT to
tempts to ventilate the intubated neonate with a flow- recommend?
inflating manual resuscitator. During ventilation
attempts, the CRT is unable to generate an effective A. noninvasive positive pressure breathing
delivery pressure and tidal volume with each bag com- B. nasal CPAP breathing
pression. The oxygen line is patent and is connected to C. controlled positive pressure breathing
the bag and to the flow meter, which is set at 12 D. inverse ratio ventilation
liters/min. What should the CRT do at this time?
IIA1h(4)
A. Change the flow meter.
20. A patient, brought to the emergency department, is
B. Compress the flow-inflating bag more frequently.
suspected of having experienced smoke inhalation.
C. Pinch the tail of the bag during inflation and com-
Which of the following forms of oxygenation moni-
pression.
toring is most appropriate for this patient at this time?
D. Increase the liter flow of oxygen to flush.
A. arterial blood gas analysis
IIA1b B. transcutaneous monitoring
17. A cascade humidifier is being used to humidify an air- C. co-oximetry
oxygen mixture from a blender. Water inside the unit is D. pulse oximetry
seen moving up the cascade tower and into the tubing
connected to the cascade inlet. What should the CRT IIA1a(1)
do to correct this problem? 21. A CRT is summoned to a patient’s room to set up a
nasal cannula to 2 liters/minute. Upon arrival, the
A. Increase the inspiratory flow rate to oppose the
physician asks the CRT to evaluate the patient to con-
back flow of the water.
firm his order. The evaluation presents the following
B. Inspect the status of the one-way valve at the bot-
findings:
tom of the tower.
C. Remove some water from the overfilled humidi- 60-year-old female
fier. weight: 50 kg
D. Replace the diffusion grid inside the cascade hu- ventilatory pattern: irregular and inconsistent
midifier. tidal volume: 200 to 350 ml
ventilatory rate: 24 to 34 breaths/minute
IIA1f(3) Which of the following recommendations should the
18. A patient has had a permanent tracheostomy and has a CRT make to the physician?
conventional tracheostomy tube inserted. The physi-
cian asks the CRT to recommend a tracheostomy tube A. Maintain the order at 2 liters/minute via the nasal
that will afford this patient the ability to breathe cannula.
through the upper airway and to possibly speak. Which B. Recommend changing the order to read, “28% air
of the following tracheostomy tubes should the CRT entrainment mask.”
select? C. Change the order to prescribe a nasal cannula at 4
liters/minute.
A. fenestrated tracheostomy tube D. Change the order to indicate a 35% aerosol mask.
B. Kamen-Wilkinson Fome-Cuff tracheostomy tube
C. Lanz tracheostomy tube IIA1b
D. Jackson tracheostomy tube
22. Which of the following humidifiers would be appro-
priate to use with adult mechanical ventilators?
IIA1e(2)
19. A COPD patient has the following arterial blood gas I. bubble
data while breathing 2 liters/min. of oxygen from a II. bubble-jet
nasal cannula. III. cascade
IV. wick
PaO2 55 torr V. pass-over
PaCO2 70 torr

Chapter 4: Equipment 201

 A. III, V only IIA1h(4)
B. I, II, IV only 27. Which of the following methods of oxygen analysis is
C. III, IV only most appropriate to use for monitoring a patient’s oxy-
D. II, III, IV, V only genation status during bronchoscopy?
A. pulse oximetry
IIA1e(1) B. arterial blood gas analysis
23. A CRT in the adult CCU is mechanically ventilating a C. co-oximetry
patient with a Bennett 7200a. Without changing any D. transcutaneous monitoring
other settings, the CRT changes the flow pattern from
a constant flow to a decelerating flow. Which of the IIA1j
following statements is true regarding this change? 28. An 18-month-old cystic fibrosis patient is having in-
A. The inspiratory time increases while the peak creased, thick tracheobronchial secretions. Which of
flow and ventilatory rate remain unchanged. the following devices would be best suited for this pa-
B. The peak flow increases while the inspiratory tient?
time and ventilatory rate remain unchanged. A. incubator
C. The ventilatory rate decreases while the inspira- B. mist tent
tory time and peak flow remain unchanged. C. aerosol mask
D. The inspiratory time and peak flow decrease D. oxyhood
while the ventilatory rate remains unchanged.
IIA1e(2)
IIA1f(2) 29. A patient who received mechanical ventilatory assis-
tance for acute ventilatory failure was weaned from
24. A 45-year-old male patient of average stature requires mechanical ventilation and extubated 10 hours ago.
endotracheal intubation. Which of the following endo- The patient, receiving 60% oxygen by aerosol mask,
tracheal tube sizes should the CRT select? is now experiencing dyspnea and increased WOB.
Which of the following actions should the CRT take at
A. 6.5 mm I.D. this time?
B. 7.5 mm O.D.
C. 8.5 mm I.D. A. Intubate the patient and administer oxygen via a
D. 9.0 mm I.D. T-piece.
B. Initiate NPPV.
C. Increase the patient’s FIO2.
IIA1q D. Intubate and reinitiate mechanical ventilation.
25. Which of the following accessory devices would be
appropriate to use with an MDI for administration of IIA1a(1)
metaproterenol to a patient who has hand-breath coor- 30. Which of the following oxygen-delivery devices is best
dination difficulty? suited for respiratory emergencies and for short-term
A. incentive indicator oxygen therapy demanding moderate to high FIO2s?
B. spacer A. air entrainment mask
C. mask B. simple mask
D. one-way valve C. nonrebreathing mask
D. partial rebreathing mask
IIA1m(1)
26. The CRT is about to assess the respiratory muscle IIA2
strength of a ventilator patient by measuring the MIP. 31. During CPR, a patient vomits into the mask used for
All of the following equipment would be appropriate bag-mask ventilation. The vomitus contaminates the
to accomplish this task EXCEPT bag and valve assembly. How should the CRT process
this equipment?
A. a linear pressure gauge calibrated from 0 to –100
cm H2O. A. Place the mask, valve assembly, and bag into a
B. a patient adaptor with one-way valves. glutaraldehyde solution for one hour.
C. connection tubing. B. Rinse the equipment clean of all debris and pas-
D. nose clips. teurize the equipment.

202 Chapter 4: Equipment

 C. Rinse the equipment clean of all debris and place IIA1f(1)
it in glutaraldehyde for three hours. 35. A CRT receives an order to insert a nasopharyngeal
D. Rinse the equipment clean of all debris and place airway in order to facilitate suctioning. What is the
it in an ethylene oxide sterilizer. proper method to determine the correct length of the
airway to be inserted?
IIA1s
I. Measure the distance from the tip of the nose to
32. For the past 48 hours, a patient who has acute atelec-
the targus of the ear, and add one inch.
tasis caused by retained secretions has been encour-
II. Measure the distance from the tip of the nose to
aged to cough following aerosol therapy and chest
the meatus of the ear.
physiotherapy in an attempt to clear the secretions.
III. Measure the distance from the tip of the nose to
The patient’s most recent chest radiograph reveals at-
the targus of the ear, and subtract one inch.
electasis in the right middle lobe and the absence of air
IV. Measure the distance from the tip of the nose to
bronchograms. Which of the following procedures is
the meatus of the ear, and subtract one inch.
indicated at this time?
A. I, II only
A. fiberoptic bronchoscopy
B. I, IV only
B. thoracentesis
C. II, III only
C. thoracoscopy
D. III, IV only
D. mediastinoscopy

IIA1a(2) IIA1m(1)
33. Which of the following statements concerning an 36. The CRT wants to check the working pressure on a
open-top tent are correct? Thorpe tube regulator. The CRT has access to several
pressure manometers—all of which can be attached to
I. There is no cooling ability other than evaporation
the regulator, but none that are calibrated in psig.
of the aerosol.
Which one of the following manometers should be
II. Oxygen concentrations of 30% to 40% are possi-
used?
ble with flows of 10 to 15 liters/minute.
III. Flows of 20 to 40 liters/minute are recommended I. a manometer calibrated in kPa from 0 to 700 kPa
to keep the tent temperature from rising above II. a manometer calibrated in cm H2O from 0 to
ambient temperature and to minimize CO2 accu- 3,000 cm H2O
mulation. III. a manometer calibrated in mm Hg from 0 to 2,000
IV. The primary function is to provide humidity. mm Hg
IV. a manometer calibrated in inches Hg from 0 to 50
A. I, II only
inches Hg
B. I, II, IV only
C. III, IV only A. I only
D. I, III, IV only B. II only
C. I, III only
IIA1b D. II, IV only
34. A heat moisture exchange might not be a suitable
humidification device for use in which of the follow- IIA1l
ing situations:
37. All of the following statements are associated with the
I. patients who have low tidal volumes clinical use of mechanical percussors EXCEPT
II. normothermic patients who are adequately hy-
A. they provide more effective therapy than manual
drated
percussion.
III. patients who have excessive amounts of secretions
B. they are less tiring for the practitioner than man-
IV. patients who have large airway leaks
ual percussion.
A. I, II only C. they facilitate quality control of therapeutic appli-
B. II, IV only cation of chest physiotherapy.
C. I, III, IV only D. the frequency of vibrations/percussions can be
D. III only varied.

Chapter 4: Equipment 203

IIA1a(3) C. liquid oxygen system
38. A 52-year-old adult male is diagnosed with obstructive D. portable liquid oxygen container
sleep apnea. Which of the following modes of therapy
might be beneficial in relieving the patient’s symptoms? IIA1f(4)
43. A CRT is preparing to perform orotracheal intubation
A. mask CPAP
on a neonate. All of the following intubation equip-
B. IPPB Q4h
ment is required for this procedure EXCEPT
C. nasopharyngeal airway
D. bronchodilator therapy before sleep I. a MacIntosh laryngoscope blade.
II. tape.
IIA1b III. a manual resuscitation bag.
39. All of the following statements are characteristics of IV. a stethoscope.
heat moisture exchangers EXCEPT A. I only
A. they are designed to attach directly to artificial B. II only
airways. C. I, III only
B. they contain hygroscopically treated material. D. II, IV only
C. the efficiency of the device depends on the size of
the inspired tidal volume. IIA1d
D. they are primarily used for long-term support of s- 44. While providing ventilation via a self-inflating manual re-
pontaneously breathing patients. suscitator during resuscitation of a nonintubated adult pa-
tient, the CRT feels air moving around his hand (which he
IIA1a(2) is using to secure and to seal the mask to the patient’s
40. A patient with a tracheostomy needs oxygen therapy. face). The flow meter is delivering 12 liters/min. to the
Which of the following oxygen delivery devices bag. What should the CRT do at this time?
would be most appropriate? A. Squeeze the manual resuscitator more vigorously.
A. aerosol mask B. Obtain a larger-size mask.
B. face tent C. Reduce the liter flow of oxygen from the flow meter.
C. tracheostomy collar D. Increase the frequency of bag compression.
D. air-entrainment mask
IIA1h(5)
IIA1k 45. Aside from a carbon monoxide gas analyzer, what
41. While auscultating the chest of a 35-year-old non- other gas analyzer(s) is (are) necessary when perform-
smoking patient who underwent a thoracotomy two ing the single-breath carbon monoxide lung diffusing
days ago, the CRT hears fine, late inspiratory crackles capacity test?
over the region of the right middle lobe. The patient is I. oxygen analyzer
oriented and coherent and has a respiratory rate of 22 II. nitrogen analyzer
breaths/min. The patient’s most recent chest X-ray re- III. helium analyzer
veals an increased opacity in the region of the right IV. carbon dioxide analyzer
middle lobe. Which of the following devices should
the CRT recommend for this patient? A. I only
B. III only
A. IPPB device C. I, III only
B. incentive spirometer D. II, IV only
C. peak flow rate
D. volume displacement pneumotachometer IIA1a(2)
46. A patient who has an endotracheal tube requires
IIA1h(2) an FIO2 of 0.45. Which of the following oxygen-
42. A home care oxygen-therapy patient needs a conve- administration devices would be most appropriate?
nient and reliable source of oxygen. Which of the fol-
lowing modes of delivery would be most appropriate A. a high-flow air-entrainment device
to select? B. a T-piece
C. a face tent
A. oxygen concentrator D. a tracheostomy collar
B. compressed gas cylinders

204 Chapter 4: Equipment

IIA1g I. heated-wire flow sensor
47. Which of the following suction catheters would be II. pressure-differential pneumotachometer
most appropriate to facilitate the entrance to the left III. water-sealed spirometer
mainstem bronchus? IV. wedge spirometer

A. whistle-tip catheter A. I, II only

B. Coudé suction catheter B. III, IV only
C. Yankauer suction tip C. II, III only
D. ring-tip catheter D. I, IV only

IIA1i(1) IIA1f(4)
48. Which of the following equipment are necessary 52. The CRT is preparing to nasotracheally intubate an
components of a ventilatory breathing circuit? awake adult patient. Which of the following equipment
would be necessary?
I. large-bore inspiratory limb
II. small-bore expiratory limb I. 0.25% phenylephrine spray
III. exhalation manifold II. Magill forceps
IV. airway adaptor III. 30-cc syringe
V. patient Y-connector IV. 2% lidocaine spray

A. I, II, III, IV, V A. I, III only

B. I, II, III, V only B. I, II, IV only
C. II, III, V only C. II, III, IV only
D. I, III, IV, V only D. I, II, III, IV

IIA1a(3) IIA2
49. An alert and cooperative patient who has a PaO2 of 40 53. The CRT is preparing respiratory therapy equipment
torr while receiving an FIO2 of 0.60 is considered to be for sterilization. Which of the following processing in-
in acute oxygenation failure. The expectation is that dicators best demonstrates that sterilization has actu-
the patient will require oxygenation for the next 24 ally occurred?
to 72 hours. Which of the following devices would A. a chemical indicator
most appropriate for administering oxygen to this B. a light-sensitive indicator
patient? C. a heat-sensitive indicator
A. nonrebreathing mask D. a biologic indicator
B. mechanical ventilator
C. air-entrainment mask IIA1m(1)
D. mask CPAP 54. The CRT has been asked to measure a patient’s MIP.
Which of the following instruments should he select to
IIA1a(2) obtain this measurement?
50. A stable, normothermic infant who is born at 32 A. pneumotachometer
weeks’ gestation is in need of oxygen therapy. Which B. pressure transducer
of the following oxygen appliances would be most C. pressure strain-gauge
suitable for this infant? D. pressure manometer
A. oxygen tent
B. oxyhood IIA1a(1)
C. oxygen mask 55. A home care, COPD patient complains about the un-
D. isolette aesthetic appearance and the nasal irritation caused by
a nasal cannula. Which of the following oxygen ther-
IIA1n apy devices should the CRT select for this patient?
51. The CRT is asked to perform bedside spirometry. He A. simple oxygen mask
wants to use instrumentation that is lightweight and B. transtracheal oxygen catheter
easily portable. Which of the following devices should C. nasal mask
he select? D. nasal catheter

Chapter 4: Equipment 205

IIA1l A. Berman airway
56. The CRT is about to perform chest physiotherapy on B. Guedel airway
an infant and notices that his hands are too large to ad- C. partial rebreathing mask
minister the therapy effectively. Which of the follow- D. mouth-to-valve mask
ing devices should he select to give the treatment?
IIA1i(2)
I. manual percussor
61. Which of the following statements concerning com-
II. flutter valve
mon PEEP mechanisms are correct?
III. electrically powered percussor
IV. pneumatically powered percussor I. For an underwater PEEP column to be functional
as a threshold resistor, the container inlet and out-
A. I only
let must be unrestricted.
B. III, IV only
II. A spring-loaded diaphragm PEEP device might
C. I, III, IV only
create expiratory resistance.
D. I, II, III, IV
III. A pressurized balloon valve is the most common
mechanism used to generate PEEP.
IIA1k IV. A spring-loaded diaphragm PEEP device might
57. A 48-year-old non-smoking patient has been hospital- create an expiratory retard.
ized to undergo a cholecystectomy. Which of the fol-
lowing preoperative instructions should the patient A. I, III only
receive? B. II, III only
C. I, IV only
A. CPR D. I, II, III, IV
B. incentive spirometry
C. MDI IIA1h(4)
D. IPPB
62. When preparing to perform an arterial puncture with a
vented arterial sampler and crystalline anticoagulant,
IIA1a(2) how should the CRT prepare the device to collect a
58. Which of the following oxygen-administration devices 2.5-ml blood sample?
would be most appropriate for an infant requiring
heated humidity and a consistent FIO2? A. Pre-set the sampler plunger to 2.5 ml.
B. Place the sampler in ice water.
A. incubator C. Aspirate 2.5 ml of normal saline into the sampler.
B. mist tent D. Eliminate any air from the sampler.
C. oxyhood
D. croupette IIA1c
63. All of the following are functional characteristics of an
IIA1b ultrasonic nebulizer EXCEPT
59. What would be the most appropriate humidification
system for a patient who has an artificial airway in A. The device utilizes oxygen as carrier gas for
place? aerosol to deliver a precise FIO2.
B. The device incorporates a piezoelectric transducer
I. cool humidity to produce aerosol.
II. heated aerosol C. The device uses an adjustable blower to deliver
III. cool water vapor aerosol to the patient.
IV. heated humidity D. The device produces up to 6 ml/minute of aerosol
A. I, II only output.
B. II, IV only
C. I only IIA1a(1)
D. II only 64. A 47-year-old non-smoking patient in the recovery
room following open-heart surgery is in need of oxy-
IIA1d gen therapy. Which of the following delivery devices
60. Which of the following devices is appropriate to use would be most appropriate?
for temporarily administering ventilation during CPR A. partial rebreathing mask
when a manual resuscitator is not available? B. nasal catheter

206 Chapter 4: Equipment

 C. air entrainment mask IIA2
D. simple mask 69. A CRT works at a hospital that uses recyclable ventilator
tubing. A patient who tested positive for pulmonary tu-
IIA1k berculosis died after coding while receiving mechanical
65. Which of the following equipment is designed to en- ventilation. A coronary artery bypass patient is expected
courage deep breathing and to prevent post-operative to be in the ICU in one hour. All of the ventilator circuits
atelectasis? are in use. How should the CRT process the ventilator
circuit to prevent transmission of the tuberculosis mi-
A. peak flow meters
croorganism to the patient who will use the tubing next?
B. chest percussors
C. flutter devices I. ethylene oxide sterilization
D. incentive spirometers II. steam autoclaving
III. pasteurization
IIA1h(2) IV. glutaraldehyde
66. A home-care oxygen patient still maintains a relatively A. I, II only
active lifestyle but feels confined with his present B. II, III only
oxygen-delivery system. Which of the following sys- C. I, IV only
tems would provide the patient with the largest degree D. III, IV only
of mobility?
A. oxygen concentrator IIA1a(1)
B. compressed oxygen D cylinders 70. Which of the following oxygen-delivery devices
C. compressed oxygen E cylinders would be appropriate for a stable COPD patient who is
D. liquid-oxygen system mildly hypoxemic and normocapnic?
A. air-entrainment mask
IIA1b B. simple mask
67. Which of the following types of humidifiers should the C. nasal cannula
CRT select to reduce the accumulation of water in the D. partial rebreathing mask
circuit of a mechanical ventilator?
A. heat and moisture exchanger IIA1i(2)
B. heated cascade humidifier 71. All of the following mechanisms can be used to pro-
C. heated wick humidifier duce PEEP EXCEPT
D. heated pass-over humidifier
A. a spring-loaded disk valve.
B. a magnetic valve.
IIA1n C. a Rudolph valve.
68. The CRT needs to measure a patient’s expiratory vol- D. a Venturi valve.
ume and airflow rates. The CRT prefers an instrument
that has few moving components, thereby minimizing IIA1h(3)
the source of error related to rapid changes in the pa-
72. An oxygen supply is needed to transport a patient from the
tient’s airflow patterns during inspiration and exhala-
hospital to an adjacent nursing home. Which of the fol-
tion. Which of the following devices should the CRT
lowing supply systems is appropriate to use for transport?
choose?
A. manifold system
I. pressure-differential flow-sensing device
B. liquid oxygen reservoir
II. water-sealed spirometer
C. air compressor
III. volume-displacement device
D. oxygen gas cylinder
IV. heated wire-flow sensor
A. I, II only IIA1g
B. II, IV only 73. Which of the following suction catheters would cause
C. II, III only the LEAST amount of mucosal damage or bleeding?
D. I, IV only
A. whistle tip with two side ports
B. straight ring tip with four side ports

Chapter 4: Equipment 207

 C. whistle tip without side ports IIA1h(1)
D. straight tip with two side ports 78. The CRT is preparing to assist with transporting a patient
to another hospital about 45 minutes away by ambulance.
IIA1f(4) The patient is receiving oxygen via a nasal cannula at 2
74. Which of the following statements concerning laryn- liters/min. from an E cylinder. Which of the following
goscope blades are true? regulators would be most appropriate for this situation?
I. A Miller blade is placed under the epiglottis, ex- A. Bourdon gauge flow meter and a Bourdon pressure
posing the glottis when lifted and providing a gauge reducing valve with a DISS connection
greater visualization of the glottic opening. B. compensated Thorpe flow meter and a Bourdon pres-
II. A MacIntosh blade is placed in the vallecula, sure gauge reducing valve with a DISS connection
causing less epiglottic stimulation (and therefore, C. compensated Thorpe flow meter and a Bourdon pres-
less chance of laryngospasm). sure gauge reducing valve with a PISS connection
III. A straight blade is preferred in a pediatric patient, D. Bourdon gauge flow meter and a Bourdon pres-
because the device enables greater exposure of the sure gauge reducing valve with a PISS connection
glottis and better exposure of the larynx.
IV. Laryngoscopes are made for right-handed persons. IIA1f(3)
A. I, III, IV only 79. A physician intends to wean a patient from a tra-
B. II, III only cheostomy tube but still wants to prevent the stoma
C. I, II, IV only from closing and wants to maintain access to the tra-
D. I, II, III, IV chea for suctioning or for emergency ventilation.
Which of the following devices should the CRT select
IIA1e(1) to accomplish these purposes?
75. Regarding the classification of mechanical ventilators, A. Lanz tracheostomy tube
to which of the following mechanisms does the classi- B. tracheal button
fication electric refer? C. speaking tracheostomy tube
D. Passy-Muir valve attached to a Kamen-Wilkinson
A. cycling mechanism
Fome-Cuff tracheostomy tube
B. powering mechanism
C. monitoring mechanism
D. gas-flow mechanism
IIA1g
80. Which of the following suction devices is appropriate
IIA1a(1) to use for removing vomitus or large particulate for-
eign matter from the oropharynx?
76. A patient who is brought to the emergency department
is lethargic and has the scent of smoke on her clothes. A. Lukens suction tube
She is in need of oxygen therapy. Which of the fol- B. Coudé suction catheter
lowing oxygen-delivery devices is most appropriate C. Yankauer tonsil tip
for her at this time? D. Olympic suction catheter
A. partial rebreathing mask
B. nonrebreathing mask
IIA1a(2)
C. air-entrainment mask 81. A CRT is asked to deliver 60% oxygen to a tra-
D. simple mask cheotomized patient. The department uses standard
nebulizers with a variable FIO2 setting of 0.35 to 1.0.
IIA1h(4) Which of the following oxygen-delivery devices is the
most appropriate for the CRT to use?
77. Which of the following monitoring techniques is ap-
propriate to use during endotracheal intubation? A. tracheostomy collar
B. T-piece
A. electrocardiography
C. canopy device
B. indirect calorimetry
D. air-entrainment mask
C. conjunctival PO2 monitoring
D. capnography
IIA1m(1)
82. An 80-kg, adult, male trauma patient has just been in-
tubated with a 7.0 mm I.D. oral endotracheal tube that

208 Chapter 4: Equipment

 has a low compliant cuff. Mechanical ventilation is C. simple face mask
also instituted. The CRT wants to measure the patient’s D. oxyhood
cuff pressure by using a cuff manometer calibrated in
1 cm H2O increments from 0 to 60 cm H2O. What IIA1d
should the CRT do at this time? 86. Within what pressure range will the safety-relief valve
A. Deflate the cuff to the minimal occluding volume of a self-inflating resuscitation bag operate?
before measuring the cuff pressure. A. 30 to 35 cm H2O
B. Measure the cuff pressure first, then establish the B. 25 to 30 cm H2O
minimal occluding volume. C. 20 to 25 cm H2O
C. Measure the cuff pressure first when a complete D. 15 to 20 cm H2O
seal is formed.
D. Do not use the cuff manometer to measure this pa- IIA2
tient’s cuff pressure without the cuff manometer.
87. Which of the following procedures is (are) appropriate
to use routinely for processing ventilatory tubing?
IIA1i(2)
83. Which of the following design criteria should be con- I. ethylene oxide sterilization
sidered essential for an effective CPAP system? II. 70% ethyl alcohol solution
III. high-level disinfectants
I. System flows capable of 60 to 90 liters/minute IV. pasteurization
accompanied by a reservoir system must be pro-
vided. A. II, IV only
II. The system must behave as a true threshold resis- B. I, III, IV only
tor, ideally generating no flow resistance. C. I, II, III only
III. An open system with flows of 20 to 30 D. I, II, III, IV
liters/minute with a reservoir capacity of 2 to 3
liters/minute is required. IIA1h(4)
IV. Incorporation of a molecular high-humidity de- 88. Which of the following device(s) would be suitable for
vice, such as a Bennett cascade humidifier or a monitoring hyperoxia in a neonate?
wick-type humidifier, is needed.
I. pulse oximeter
A. II, III only II. transcutaneous oxygen electrode
B. II, III, IV only III. co-oximeter
C. I, II, IV only IV. arterial blood gas analyzer
D. I, IV only
A. IV only
B. I, III only
IIA1h(2)
C. II, IV only
84. Which of the following features are characteristic of a D. II, III, IV only
piston-driven air compressor?
I. high flow output IIA1h(1)
II. capability of producing 50 psig 89. Which of the following high-pressure reducing valves
III. reservoir to meet peak flow demands should be selected when a working pressure of less
A. I, II only than 50 psig is needed?
B. I, III only A. adjustable reducing valve
C. II, III only B. preset reducing valve
D. I, II, III C. present, single-stage reducing valve
D. multiple-stage reducing valve
IIA1a(2)
85. Which of the following devices is the most appropriate IIA1a(2)
device for administering cool aerosol therapy to a 90. Which oxygen-delivery device would be most appro-
three-year-old child who is diagnosed with laryngotra- priate if the physician wishes to deliver oxygen to the
cheobronchitis? patient at 24%?
A. oxygen tent A. nasal cannula at 1 liter/minute
B. mist tent B. partial rebreathing mask

Chapter 4: Equipment 209

 C. simple mask at 5 liters/minute IIA2
D. air-entrainment device 96. Which of the following procedures is appropriate for
processing bronchoscope biopsy forceps and brushes?
IIA2
I. glutaraldehyde
91. How should the CRT decontaminate a fiberoptic bron-
II. ethylene oxide sterilization
choscope that has been used on a patient who has lung
III. steam autoclaving
cancer?
IV. pasteurization
A. glutaraldehyde
A. II, III only
B. pasteurization
B. I, IV only
C. 90% isopropyl alcohol
C. I, II, III only
D. acetic acid
D. II, III, IV only
IIA1h(4)
IIA1h(4)
92. The CRT wants to monitor the oxygen saturation of a
97. Which of the following methods of oxygen analysis is
patient who is prone to having episodes of poor perfu-
best suited when prescribing oxygen therapy for a
sion. Which of the following monitoring techniques
home-care patient?
would be best suited for this type of patient?
A. co-oximetry
A. arterial and mixed venous blood-gas analysis
B. transcutaneous oxygen monitoring
B. pulse oximeter with a plethysmographic wave-
C. arterial blood-gas analysis
form display
D. pulse oximetry
C. co-oximetry of arterial and mixed venous blood
D. transcutaneous monitoring
IIA1f(1)
IIA1d 98. When is the use of an oropharyngeal airway indicated?
93. All of the following manual resuscitators enable A. in all bag-mask ventilation situations
spontaneous breathing to open the patient valve for B. when tracheobronchial suctioning is difficult
oxygen EXCEPT C. when performing bag-mask ventilation on a co-
matose patient
A. Hope II.
D. only in ventilatory arrest cases
B. AMBU E-2.
C. Laerdal.
D. PMR II.
IIA1f(2)
99. A CRT has been assigned to the pediatric unit and is
IIA1f(1) responsible for supplying the emergency airway
equipment. What endotracheal tube sizes should she
94. For which of the following patients would an oropha-
recommend for insertion for an eight-year-old patient?
ryngeal airway be most appropriate?
A. 5.5 mm, 6.0 mm, and 6.5 mm I.D.
A. an alert patient who requires frequent nasotra-
B. 4.5 mm and 5.5 mm I.D.
cheal suctioning
C. 5.5 mm, 6.0 mm, and 6.5 mm O.D.
B. a comatose patient who has a tracheotomy tube in
D. 4.5 mm and 5.5 mm O.D.
place
C. an unconscious patient who requires ventilation
before endotracheal intubation
IIA1f(4)
D. a semicomatose patient with a history of aspira- 100. A motor vehicle accident victim who has oral trauma
tion requires nasotracheal intubation. Which of the follow-
IIA1f(2) ing devices should be used to assist with insertion of
95. Which of the following volume-pressure characteris- the endotracheal tube through the larynx?
tics should an adult endotracheal tube cuff have? A. MacIntosh blade
A. high residual volume and low pressure B. straight blade
B. high residual volume and high pressure C. curved blade
C. low residual volume and low pressure D. Magill forceps
D. low residual volume and high pressure

210 Chapter 4: Equipment

IIA1g IV. They require a single connection to a 50 psig oxy-
101. Which statement represents one of the criteria of a suc- gen source.
tion catheter for suctioning through an ET tube? V. They incorporate a dual orifice proportional valve.

A. The catheter’s external diameter should not exceed A. I, II, III, V only
one-half of the internal diameter of the ET tube. B. I, III, IV only
B. As long as the suction catheter will pass through C. II, V only
the ET tube, the catheter can be used. D. II, III, IV, V only
C. The suction catheter having the largest internal di-
ameter should be used so that laminar flow IIA1g
through the catheter will be maintained. 106. Which of the following substances is used in conjunc-
D. During intubation, the largest ET tube should be tion with collecting a sputum sample for cytology via
chosen so that the largest suction catheter possible a wide-mouthed, screw-top collection jar?
can be used when suctioning will be performed.
A. 20 ml of bacteriostatic saline
B. 20 ml of isotonic saline
IIA1h(4) C. 15 ml of 50% ethyl alcohol and 5 ml 3% NaCl
102. A patient who has a hemoglobin concentration of 8 D. 20 ml of 50% ethyl alcohol and 2% carbowax
g/dl has a pulse oximetry reading of 80%. What action
would be appropriate at this time? IIA1i(2)
A. The reading should be accepted. 107. All of the following devices are critical components of
B. An arterial blood-gas analysis must be performed. a CPAP system EXCEPT
C. An arterial blood sample needs to be analyzed via
A. a reservoir bag.
a co-oximeter.
B. a one-way pop-off valve.
D. Arterial and mixed venous blood samples need to
C. a nebulizer.
be analyzed.
D. a threshold resistor.
IIA1h(1)
IIA1g
103. Which of the following flow-regulating devices should
108. When assembling a system to obtain a sputum speci-
be used to transport a patient who is receiving oxygen
men from an intubated patient, where should the CRT
if the compressed gas tank is secured in a horizontal
place the sterile sputum trap or specimen collector?
position?
A. between the artificial airway and the suction
A. a pressure-compensated Thorpe tube
catheter
B. a Bourdon gauge
B. between the suction catheter and the suction tubing
C. a flow restrictor
C. between the vacuum-regulating device and the
D. a pressure regulator
suction tubing
D. between the vacuum reservoir and the suction tubing
IIA1h(3)
104. A CRT is called to the nuclear medicine department to
IIA1h(1)
determine the approximate time that an H cylinder of
oxygen will last. The regulator reads 900 psig, and the 109. A patient being transported on oxygen is using a nasal
patient is receiving oxygen via a nasal cannula at 6 cannula at 4 liters/minute. The cannula is connected to
liters/minute. How long will the cylinder last? a Bourdon type regulator attached to an E cylinder.
When the side rail of the bed is raised into position, the
A. six hours and 10 minutes tubing connecting the cannula to the regulator be-
B. seven hours and 50 minutes comes kinked—occluding the oxygen flow. What will
C. eight hours and 30 minutes be the effect of this occlusion?
D. nine hours and 15 minutes
A. The flow indicated on the gauge will drop to zero.
IIA1h(1) B. The flow indicated on the gauge will continue to
read 4 liters/minute.
105. Which of the following characteristics are associated
C. The flow indicated on the gauge will increase
with the operation of air-oxygen blenders?
higher than 4 liters/minute.
I. They can provide a consistent FIO2. D. The flow indicated on the gauge will decrease
II. They use an internal pressure-balancing system. slightly lower than 4 liters/minute.
III. They can be used for continuous flow CPAP sys-
tems.

Chapter 4: Equipment 211

IIA1h(2) IIA1g
110. What is the purpose of air compressors in the practice 111. Which of the following statements are true concerning
of respiratory care? endotracheal tube suctioning?
A. to produce uniform aerosol particles for aerosol I. In some instances, suctioning should be ordered
therapy on a predetermined basis.
B. to scrub oxygen from the air for oxygen therapy II. Endotracheal tube suctioning can be routinely
C. to power equipment used for respiratory care pro- performed as long as 25 seconds.
cedures III. Vagal nerve stimulation is a possible complication
D. to compress air for use in sterilization procedures of tracheal suctioning.
IV. The suction catheter should occupy as much as
50% of the internal diameter of the ET tube.
A. I, II, III, IV
B. III, IV only
C. I, II, IV only
D. II, III only

212 Chapter 4: Equipment

 STOP
You should stop here to evaluate your performance on the 111 questions relating to matrix sections IIA1 and IIA2.
Use the Entry-Level Examination Matrix Scoring Form in Table 4-3 referring to equipment sections IIA1 and IIA2.
After you evaluate your performance on matrix sections IIA1 and IIA2, refer to the Equipment portion of the NBRC
Entry-Level Exam Matrix (Table 4-4) found on page 214. Then, continue with the equipment assessment.
Table 4-3: Equipment—Entry-Level Examination Matrix Scoring Form for Content Areas IIA1 and IIA2

Entry-Level Examination Equipment Equipment Items Equipment Content

Content Area Item Number Answered Correctly Area Score

IIA1. Select and obtain equipment 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12,

appropriate to the respiratory 13, 15,16, 17, 18, 19, 20, 21, 22,
care plan. 23, 24, 25,26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49,
50, 51, 52, 54, 55, 56,57, 58, 59, __  100 = ____%
___
60, 61, 62, 63, 64, 65, 66, 67, 68, 104 __  100 = ____%
___
70, 71, 72, 73, 74, 75, 76, 77, 78, 111
79, 80, 81, 82, 83, 84, 85, 86, 88,
89, 90, 92, 93, 94, 95, 97, 98, 99,
100, 101, 102, 103, 104, 105, 106,
107, 108, 109, 110, 111

IIA2. Assure equipment cleanliness. 3, 14, 53, 69, 87, 91, 96 _  100 = ____%
7

Chapter 4: Equipment 213

Table 4-4: NBRC Certification Examination for Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
N

N
g. suctioning devices [e.g., suction
II. Select, Assemble, and catheters, specimen collectors,
oropharyngeal suction devices] x
Check Equipment for Proper h. gas delivery, metering and clinical
Function, Operation and analyzing devices x
Cleanliness (1) regulators, reducing valves,
connectors and flow meters, air/
SETTING: In any patient care oxygen blenders, pulse-dose
setting, the respiratory therapist systems x
selects, assembles, and assures (2) oxygen concentrators, air
cleanliness of all equipment used compressors, liquid-oxygen systems x
in providing respiratory care. The (3) gas cylinders, bulk systems and
therapist checks all equipment manifolds x
and corrects malfunctions. (4) capnograph, blood gas analyzer
and sampling devices, co-oximeter,
transcutaneous O2/CO2 monitor,
A. Select, obtain, and assure equipment pulse oximeter x
cleanliness. 5 8 0 (5) CO, He, O2 and specialty gas analyzers x
1. Select and obtain equipment appropriate i. patient breathing circuits
to the respiratory care plan: (1) IPPB, continuous mechanical ventilation x
a. oxygen administration devices (2) CPAP, PEEP valve assembly x
(1) nasal cannula, mask, reservoir mask j. aerosol (mist) tents x
(partial rebreathing, non-rebreathing), k. incentive breathing devices x
face tents, transtracheal oxygen l. percussors and vibrators x
catheter, oxygen conserving cannulas x m. manometers and gauges
(2) air-entrainment devices, (1) manometers—water, mercury and
tracheostomy collar and T-piece, aneroid, inspiratory/expiratory
oxygen hoods and tents x pressure meters, cuff pressure
(3) CPAP devices x manometers x
b. humidifiers [e.g., bubble, passover, (2) pressure transducers x
cascade, wick, heat moisture exchanger] x n. respirometers [e.g., flow-sensing
c. aerosol generators [e.g., pneumatic devices (pneumotachometer), volume
nebulizer, ultrasonic nebulizer] x displacement] x
d. resuscitation devices [e.g., manual o. electrocardiography devices [e.g., ECG
resuscitator (bag-valve), pneumatic oscilloscope monitors, ECG machines
(demand-valve), mouth-to-valve mask (12-lead), Holter monitors] x
resuscitator] x p. vacuum systems [e.g., pumps,
e. ventilators regulators, collection bottles, pleural
(1) pneumatic, electric, microprocessor, drainage devices] x
fluidic x q. metered dose inhalers (MDIs), MDI spacers x
(2) non-invasive positive pressure x r. Small Particle Aerosol Generators (SPAGs) x
f. artificial airways s. bronchoscopes x
(1) oro- and nasopharyngeal airways x 2. Assure selected equipment cleanliness
(2) oral, nasal and double-lumen [e.g., select or determine appropriate
endotracheal tubes x agent and technique for disinfection and/or
(3) tracheostomy tubes and buttons x sterilization, perform procedures for
(4) intubation equipment [e.g., disinfection and/or sterilization, monitor
laryngoscope and blades, exhaled effectiveness of sterilization procedures] x
CO2 detection devices] x

*The number in each column is the number of item in that content area and the cognitive level contained in each
examination. For example, in category I.A., two items will be asked at the recall level, three items at the application level,
and no items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the
respective column (Recall, Application, and Analysis).

214 Chapter 4: Equipment

 Equipment Assessment (continued)
The following 100 questions refer to Entry-Level Examination Matrix sections IIB1, IIB2, and IIB3.
IIB—Assemble and check for proper equipment function; identify and take action to correct equipment
malfunctions; and perform quality control.

NOTE: You should stop to evaluate your performance on the 100 questions pertaining to the matrix sections IIB1,
IIB2, and IIB3.
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the answer that is best in each case, then blacken the corresponding space on the
answer sheet found in the front of this chapter. Good luck.

IIB2e(2) IIB2m
112. A patient is receiving NPPV via a nasal mask for the 115. The CRT is having a tracheotomized patient perform
treatment of respiratory failure associated with cardio- an MIP maneuver to help determine the patient’s
genic pulmonary edema. The CRT notices that the ability to be weaned from mechanical ventilation.
nasal mask does not fit the patient well. Which of the The patient is a 70-kg male who has a known capa-
following measures should be taken? bility of producing a tidal volume of 400 ml. During
the inspiratory maneuver, the meter does not register
A. Intubate the patient and administer oxygen via a
any reading. What might have contributed to this sit-
T-piece.
uation?
B. Intubate the patient and apply CPAP.
C. Intubate and initiate conventional mechanical I. The patient port is open to the atmosphere and is
ventilation. not occluded.
D. Use a full face mask. II. The internal diaphragm on the pressure device is
ruptured.
IIB2j III. A tight seal is not being maintained.
113. While checking the operation of a mist tent being used A. I only
by a two-year-old child who has cystic fibrosis, the CRT B. I, III only
notices the absence of mist entering the enclosure. What C. II, III only
corrective action(s) should be taken in this situation? D. I, II, III
I. Tuck the canopy sides under the mattress.
II. Ensure that the canopy zipper is closed. IIB2h(3)
III. Check the water level in the nebulizer. 116. While working in a CCU, the CRT hears the sound of
IV. Clean the nebulizer’s jet. the area alarm of the central oxygen supply system.
A. III only Which of the following condition(s) can cause this
B. I, II only alarm to sound?
C. III, IV only I. A changeover from the primary to the secondary
D. I, II, III, IV bank has occurred.
II. The dew point in the compressed air system ex-
IIB1a ceeded its threshold.
114. A patient is receiving oxygen via a 28% air entrain- III. The level of liquid in the bulk liquid oxygen sup-
ment mask. The physician asks the CRT to provide ply reached a predetermined level.
oxygen to this patient via a nasal cannula during IV. The normal operating line pressure changed by
meals. Which of the following liter flows would de- 20% or more.
liver approximately 28% oxygen?
A. I only
A. 1 liter/minute B. IV only
B. 2 to 3 liters/minute C. II, III only
C. 4 liters/minute D. I, II, III, IV
D. 6 liters/minute

Chapter 4: Equipment 215

IIB1a(1) C. II, IV only
117. While performing oxygen rounds, the CRT is told by a D. III, IV only
patient wearing a cannula, “It feels like nothing is
coming out.” Which of the following aspects of this IIB2a(2)
oxygen-delivery device should be examined? 121. A patient is breathing via an aerosol T-piece (Figure
4-1) during weaning from mechanical ventilation.
I. that the cannula is connected to the flow meter
II. that the cannula or any of its tubing is not kinked
Aerosol tubing Aerosol T-piece
III. that the flow meter is working correctly
IV. that the humidifier is not leaking (Briggs adaptor)

A. I, II only
B. III, IV only
C. I, II, III only From aerosol generator Endotracheal
D. I, II, III, IV tube connector

IIB1b Endotracheal
tube
118. An ICU patient is receiving mechanical ventilation
with a hygroscopic condenser humidifier in place.
Over the course of a shift, the CRT notes a large in- To patient
crease in the quantity of secretions produced by the pa- Figure 4-1: Aerosol T-piece attached to an ET tube during
tient, and frequent suctioning is needed. What would weaning from mechanical ventilation.
be the appropriate action for the CRT to take? The CRT notes that the aerosol coming from the
A. replacing the hygroscopic condensing humidifier T-piece disappears with each patient inspiration and
with a heated humidifier that the patient’s SpO2 has fallen. To ensure that the
B. adding a heated humidifier to the circuit patient receives the prescribed concentration of oxy-
C. adding a second hygroscopic condensing humidi- gen, the CRT should perform which of the following
fier in tandem actions?
D. administering ultrasonic nebulization intermittently
A. Recommend that the patient receive a respiratory
depressant.
IIB1e(1)
B. Increase the FIO2 setting.
119. Which of the following conditions can expose a pa- C. Ask the patient to breathe less deeply.
tient to excessive and dangerous airway pressure while D. Add reservoir tubing to the T-piece.
being mechanically ventilated via a Babybird?
I. occlusion of the inspiratory limb of the circuit IIB2h(4)
II. occlusion of the expiratory limb of the circuit 122. A mechanically ventilated patient who is being moni-
III. obstruction of the exhalation valve charging line tored via capnography has a continuous exhaled CO2
IV. elevation of the FIO2 higher than 0.50 level of zero. An arterial blood-gas sample has just
A. I only been obtained, and the following data were obtained.
B. II only PaO2 90 torr; PaCO2 49 torr; pH 7.38; HCO 3¯ 28 mEq/L
C. II, III only
D. I, II, III, IV How should the CRT correct this problem?
A. Check to ensure that the endotracheal tube is not
IIB1h(3) in the esophagus.
120. The CRT is informed of a fire in the west wing of the B. Check for an increase in mechanical dead space.
hospital. What is the most appropriate initial response C. Check the tubing for a disconnection.
to this situation? D. Examine the exhalation valve on the ventilator
I. Disconnect all flow meters from the wall outlets circuit.
in the west wing.
II. Turn off the riser in the entire hospital. IIB1h(4)
III. Turn off the zone valve to the west wing.
IV. Provide emergency oxygen cylinders to patients 123. What are the necessary components for calibrating a
who are relocated from the west wing. transcutaneous CO2 electrode?
A. I, II only I. sodium sulfite
B. I, IV only II. barometric pressure

216 Chapter 4: Equipment

 III. gas containing 0% CO2 III. The patient will entrain more room air through the
IV. gas containing 10% CO2 ports on the mask.
IV. The actual oxygen percentage will remain constant.
A. I, III only
B. III, IV only A. I, II, III only
C. II, IV only B. I, III, IV only
D. II, III, IV only C. II, III only
D. I only
IIB1e(1)
124. Which of the following factors must be known to as- IIB1i(2)
certain the volume compressed in the ventilator circuit 128. A volume ventilator is being used in the recovery room
attached to a ventilator delivering a preset volume? to ventilate an apneic, post-operative trauma patient.
The ventilator settings include
I. PIP
II. tidal volume delivered by the ventilator mode: assist/control
III. compliance of the ventilator circuit tidal volume: 800 ml
IV. PEEP ventilatory rate: 12 breaths/minute
FIO2: 0.50
A. II, IV only PEEP: 10 cm H2O
B. I, III, IV only
C. I, II, III only During rounds, the CRT notices that the ventilator is
D. I, II, III, IV cycling at a rate of 28 breaths/minute. Additionally, the
CRT confirms that the sensitivity is set at 2 cm H2O
below the PEEP level. What are possible causes for the
IIB2e(2)
increase in the ventilatory rate?
125. The CRT is working with a patient who is receiving
NPPV. The CRT notices the IPAP and EPAP preset I. The assist is too sensitive.
pressures are not being achieved. Which of the follow- II. The tidal volume is set too low.
ing actions should be taken to correct this problem? III. The PEEP valve is malfunctioning.
IV. The circuit contains a leak.
A. Determine the status of the air-intake filter.
B. Check the fuse or circuit breaker on the machine. A. I only
C. Increase the IPAP and EPAP pressure settings. B. I, III only
D. Set the ventilator to operate in the timed mode. C. II, IV only
D. III, IV only
IIB2h(2)
IIB1c
126. The CRT is checking an air compressor and notices that
its output is low. Which of the following actions should 129. After an ultrasonic nebulizer has been in operation for
the CRT immediately take to check this problem? several minutes, the temperature of the delivered gas is
about 10ºC greater than room temperature. What ac-
I. Examine the air inlet filter. tion should the CRT take?
II. Check tubing and hoses for obstructions.
III. Check tubing and hoses for leaks. A. Replace the nebulizer.
IV. Ensure that the compressor is attached to a 50 B. Increase the gas flow through the nebulizer cup.
psig air source. C. Do nothing.
D. Add more couplant.
A. I, IV only
B. I, II, III only IIB1f(2)
C. II, III, IV only
130. Which statements can be considered advantages of
D. I, II, III, IV
nasal ET tubes as compared with oral ET tubes?

IIB1a(2) I. Nasal ET tubes are of a larger diameter, providing

for more laminar flow.
127. A patient is receiving oxygen via an air entrainment
II. Nasal tubes are considered to be better tolerated
mask set to deliver 28% oxygen. His bed sheet covers
by the patient.
the entrainment ports. Which of the following state-
III. Once inserted, nasal tubes present fewer chances
ments are true concerning this situation?
of kinking.
I. The total liter flow will decrease. IV. Nasal tubes provide a better and more secure at-
II. The FIO2 will increase. tachment for respiratory-care equipment.

Chapter 4: Equipment 217

 A. II, III, IV only PaO2 92 torr
B. I, III only PaCO2 42 torr
C. II, III only pH 7.41
D. III, IV only HCO 3¯ 26 mEq/L
The PtcO2 readout indicates 159 torr. What action(s)
IIB1h(5) should the CRT take?
131. While monitoring the FIO2 of a patient with a Tele-
dyne galvanic fuel cell analyzer, the CRT notes that the I. Check the electrode for overheating.
oxygen concentration is reading 102%. The most ap- II. Determine whether the patient’s skin perfusion
propriate initial intervention would be to has increased.
III. Inquire to find out whether the patient has re-
A. Recalibrate the analyzer. cently received any vasoactive drugs.
B. Change the electrolyte gel. IV. Examine the electrode for an adequate seal with
C. Change the fuel cell. the skin.
D. Secure another analyzer.
A. IV only
B. II, III only
IIB1k
C. I, III, IV only
132. Incentive spirometry is being administered by using D. I, II, III, IV
the Sherwood Medical Voldyne. The flow indicator
rises above the clear chamber during inspiration. What IIB1h(4)
corrective action(s) should the CRT take?
136. The CRT is using capnography to monitor a patient’s
I. Encourage the patient to take less forceful breaths. PETCO2. The capnograph displays a low PETCO2.
II. Increase the length of the patient tubing. Which of the following situation(s) can be responsible
III. Restrict flow through the mouthpiece. for this condition?
IV. Decrease the diameter of the tubing connected to
I. The patient is moving excessively.
the mouthpiece.
II. The endotracheal tube is improperly placed.
A. I only III. The sensor is positioned too far from the patient’s
B. II, III, IV only mouth.
C. II, IV only IV. The patient is experiencing an increased cardiac
D. III only output.
A. II only
IIB1a(2) B. III only
133. Which of the following liter flows is considered to be C. I, IV only
the minimum level necessary to prevent carbon dioxide D. II, III only
buildup from occurring within an oxyhood?
A. 1 to 2 liters/minute IIB1c
B. 5 to 7 liters/minute 137. The CRT is checking the aerosol output from a jet neb-
C. 10 to 14 liters/minute ulizer and notices that the aerosol output has de-
D. 16 to 20 liters/minute creased. Which of the following situations would
cause a decreased aerosol output from a jet nebulizer?
IIB1e(2) I. the absence of a reservoir bag
134. When setting up an NPPV, how should the CRT estab- II. an FIO2 of 0.70 or greater
lish the IPAP in relationship to the EPAP? III. a low water level in the reservoir
A. The IPAP and the EPAP need to be set at the same IV. a defective wick
level. A. I, II, III, IV
B. The IPAP must be set higher than the EPAP. B. I, II, III only
C. The EPAP must be set higher than the IPAP. C. II, III only
D. The patient’s condition determines whether the D. I, IV only
IPAP or EPAP level will be higher.
IIB1a(2)
IIB2h(4) 138. Which factor(s) would cause the delivered FIO2 to dif-
135. A patient who is being monitored with a transcutaneous fer from the set FIO2 on an air-entrainment oxygen-
PO2 electrode has the following arterial blood-gas data: delivery device?

218 Chapter 4: Equipment

 I. the accumulation of condensate in the tubing A. Turn the diluter control to 60%.
II. a low water level in the reservoir B. Turn the diluter control to 60% and increase the
III. an obstruction in the capillary tube in the reservoir flow rate.
IV. a defective baffle C. Turn the diluter control to 60% and connect a sec-
ond nebulizer to the tubing with a Y-connector.
A. I only
D. Leave the diluter control set at 40% and add a
B. I, III, IV only
nasal cannula at 4 liters/minute.
C. II, III, IV only
D. I, II, III, IV
IIB2g
IIB2a(2) 143. A CRT is using a closed-suction catheter system to
suction a patient who is receiving mechanical ventila-
139. While analyzing the FIO2 in different areas of a mist tion. Before introducing the suction catheter, she has
tent providing aerosol therapy to an 18-month-old cys- instilled 5 cc of normal saline through the suction sys-
tic fibrosis patient, the CRT notices that the analyzer tem’s irrigation port. The patient begins coughing im-
reading is fluctuating from 25% to 35%. What action mediately, and the PIP indicated on the pressure
should be taken by the CRT at this time? manometer suddenly falls from 35 cm H2O to 15 cm
A. Increase the oxygen flow rate on the flow meter. H2O. What might have accounted for the drop in PIP?
B. Use an oxyhood instead of a mist tent. A. The patient has developed bronchospasm.
C. Use an air-oxygen blender to provide a set FIO2. B. The removal of secretions has caused the airway
D. Ensure that all of the possible sources of leaks are resistance to decrease.
sealed. C. The irrigation port on the suction catheter was in-
advertently left open.
IIB2f(2) D. The patient Y-connector has come loose from the
140. While cutting the tape to resecure an endotracheal tube endotracheal tube adaptor on the closed-suction
of a patient who is being mechanically ventilated, the catheter system.
CRT inadvertently severs the cuff inflation line. What
should the CRT do at this time? IIB2h(1)
A. Immediately remove the endotracheal tube. 144. A CRT is asked to troubleshoot a Bourdon gauge flow
B. Insert a needle, attached to a stopcock and small meter. To understand the principle of operation, the
syringe, into the severed line and inject some air. CRT must have an appreciation of which of the fol-
C. Clamp the severed cuff inflation line with hemo- lowing physical gas laws?
stats and leave the tube in place. A. Boyle’s law
D. Recommend a STAT portable chest X-ray to B. Charles’ law
assess the status of the endotracheal tube. C. Dalton’s law
D. Poiseuille’s law
IIB1e(1)
141. While administering IPPB to an edentulous patient, IIB1q
the CRT notices that the patient is having difficulty cy- 145. In an attempt to remove vomitus from a patient’s
cling off the machine (and during some breaths is un- mouth, the CRT selects a Yankauer suction device, sets
able to cycle off the device). What adjustment would the vacuum level at –80 mm Hg, and inserts the
be appropriate for the CRT to make to correct this Yankauer suction device into the patient’s mouth. Lit-
problem? tle material enters the device. What should the CRT do
A. Make the IPPB machine less sensitive. in this situation?
B. Decrease the peak flow. A. Increase the negative suction pressure.
C. Turn off the gas flow to the nebulizer. B. Switch to a size 12 French suction catheter.
D. Activate the terminal flow control. C. Remove the Yankauer tube and use the connecting
tube leading to the suction-collection bottle.
IIB1a(2) D. Replace the Yankauer suction device with a new one.
142. The CRT has obtained an arterial blood gas from a pa-
tient who is receiving 40% oxygen aerosol from a IIB2f(3)
standard large-volume pneumatic nebulizer. The arter- 146. A patient who requires mechanical ventilation at night
ial PO2 is 50 mm Hg. The physician orders the FIO2 to breathes spontaneously through a fenestrated tra-
be increased to 0.60. To accomplish this order, the cheostomy tube with a T-piece attached during the day.
CRT should perform which of the following tasks? As the CRT re-establishes nocturnal mechanical

Chapter 4: Equipment 219

 ventilation, the low-pressure alarm on the ventilator IIB1c
sounds with each inspiration. What might be the prob- 150. Which of the following factors can reduce the aerosol
lem in this situation? output from a jet nebulizer?
A. The cuff might not have been reinflated. I. a loose DISS connection at the flow meter
B. The cuff might have been overinflated. II. a partial obstruction of the jet
C. The patient might have developed a pneumotho- III. a full water trap
rax. IV. a full nebulizer reservoir
D. The patient might require endotracheal suction-
ing. A. I, II only
B. II, IV only
IIB1a(2) C. I, II, III only
D. I, II, III, IV
147. A nurse in the neonatal ICU asks the CRT to check the
FIO2 in the oxyhood on an infant. She says that the
concentration ordered was to be 30% and she just an-
IIB1a(2)
alyzed it to be 25%. The blender supplying the oxy- 151. Which of the following figures (Figures 4-2a–d) best
hood is set at 30% and analyzes at 30%. Which of the illustrates the proper location of a heat-moisture ex-
following statements is not a likely cause for the vari- changer within a ventilator circuit?
ation?
A. The hood is too large for the infant, enabling air to A. HME
leak in around the neck.
B. The infant has too large a minute ventilation.
C. She is measuring the FIO2 near the top of the oxy-
hood.
D. The gas flow is insufficient.

IIB1h(4)
148. How can the CRT prevent thermal injury to a patient’s
skin when using a transcutaneous oxygen electrode?
A. Change the sensor site regularly.
B. Periodically lower the electrode temperature.
C. Remove the electrode from the skin occasionally.
D. Change sensors about every four hours. Inspiratory
Line
IIB2h(2) Figure 4-2a
149. A CRT enters the home of a patient who is receiving
oxygen from a nasal cannula attached to an H-cylinder.
The oxygen concentrator is not operating despite being B.
plugged into a 120-volt outlet. When the power switch
on the machine is turned to the ON position, an audi-
ble alarm sounds. What corrective measure needs to be
taken by the CRT at this time?
I. Test the outlet with a household appliance known
to work.
II. Determine why the pressure of oxygen in the HME
product tank is less than 10 psig.
III. Check the humidifier for an obstruction.
IV. Press the reset button to determine whether the
circuit breaker has tripped.
A. II, III only Inspiratory
B. I, II only Line
C. I, IV only Figure 4-2b
D. I, II, IV only

220 Chapter 4: Equipment

 C. C. Add a water-soluble lubricant to the catheter tip.
D. Check the connections at the catheter and collec-
tion container.

IIB2h(2)
154. While checking a portable liquid oxygen reservoir in
the home of a patient who is receiving oxygen via a
nasal cannula at 2 liters/min., the CRT notices that the
HME reservoir is not delivering oxygen. What action(s)
should the CRT take to evaluate this problem?
I. Test the electrical outlet by plugging in an appli-
ance known to work.
II. Verify the status of the weight scale.
Inspiratory
III. Check all connections and feel and listen for es-
Line
caping gas.
Figure 4-2c IV. Examine the filters in the system.
A. III only
D. B. I, II only
C. II, III only
D. I, II, III, IV

IIB2i(2)
155. A continuous flow CPAP system using a threshold resis-
tor is in operation on an adult ICU patient. During rounds,
the CRT notices that the needle on the manometer swings
from the prescribed 15 cm H2O to 10 cm H2O during in-
Inspiratory spiration. What can the CRT do to correct this problem?
Line
A. Replace the manometer.
B. Change the threshold resistor to a flow resistor.
HME C. Discontinue the CPAP.
D. Increase the flow rate.
Figure 4-2d
IIB2f(3)
IIB1d 156. An adult patient has a Shiley cuffed tracheostomy tube
152. What technique can be used to prevent the incidence of inserted and is receiving aerosol therapy from a
gastric insufflation during mouth-to-mask ventilation? T-piece. The patient complains of difficulty breathing.
The CRT is unable to pass a 14-Fr suction catheter into
A. inserting an oropharyngeal airway the patient’s trachea. Which of the following courses
B. adding an oxygen flow of approximately 15 of action would be appropriate to take at this time?
liters/minute
C. applying upward pressure to the mandible with A. Instill 3 cc of normal saline and try to suction again.
the index, middle, and ring fingers of both hands B. Inspect the inner cannula.
D. having a trained assistant apply pressure to the C. Replace the tracheostomy tube.
cricoid cartilage D. Increase the FIO2.

IIB1f IIB2e(1)
153. A CRT is about to nasotracheally suction a patient and 157. A Bear-2 ventilator is being used to mechanically
notes that the suction manometer reads –100 mm Hg. ventilate a patient. Suddenly, a continuous alarm
When the CRT covers the thumb port, no suction oc- sounds. When the CRT responds, he observes that the
curs at the catheter tip. At this point, the CRT should patient is showing no signs of distress and that the pa-
perform which of the following tasks? tient’s chest rises and falls in synchrony with the
cycling of the ventilator. Furthermore, the pressure
A. Increase the wall suction to –120 mm Hg. manometer needle rotates to the appropriate level with
B. Replace the suction catheter. each mechanical breath. The low exhaled volume

Chapter 4: Equipment 221

 alarm light is illuminated, and the digital display for IIB1h(2)
the tidal volume equals zero. What should the CRT do 161. While evaluating an oxygen concentrator at the home
to correct this situation? of a patient who is receiving supplemental oxygen via
A. He should disconnect the patient from the ventila- a nasal cannula, the CRT notices the oxygen concen-
tor, institute manual ventilation, and call for help. tration indicated on an oxygen analyzer, which is at-
B. He should call the biomedical department for as- tached to the concentrator, decreases from 96% to 86%
sistance. when the flow meter on the device is increased from 2
C. He should note the situation in the chart after liters/min. to 5 liters/min. What should the CRT do to
pressing the alarm silence button. correct this situation?
D. He should blot dry the ultrasonic transducer and A. Recalibrate the oxygen analyzer.
receiver surfaces of the pneumotach with a paper B. Clean the filters on the concentrator.
towel. C. Ensure that the air intake or exhaust is not blocked.
D. Nothing needs to be done, because this situation is
IIB1a(2) normal.
158. The CRT is summoned to the ICU because the low-
temperature alarm on a servo-controlled humidifier
connected to the circuitry of a ventilated patient has
IIB2i(1)
been activated. The patient is receiving CPAP and is 162. What will happen in conjunction with an IPPB device
breathing only six times per minute with a tidal vol- if the nebulizer line becomes disconnected during a
ume of 450 ml. The water-feed system and the humid- treatment?
ifier are functioning properly. What is the most likely A. The FIO2 will fluctuate.
cause for the alarm activation? B. The system flow rate will decrease.
A. An alarm malfunction has occurred. C. The system pressure will increase.
B. The low flow rate through the system prevents the D. The inspiratory phase will not terminate.
sensor from warming.
C. The room is too cool. IIB2h(1)
D. Condensate in the tubing is cooling the sensor.
163. An air-oxygen blender is set up to deliver 35% oxygen
to a patient. An oxygen analyzer indicates that a 75%
IIB2h(1)
oxygen concentration is being delivered. What should
159. As the CRT enters the room of a patient who is receiv- be the first action that the CRT takes?
ing supplemental oxygen through an air-oxygen
blender, he hears the high-pitched alarm sounding A. Use a different nebulizer.
from the blender. What is causing the alarm to sound? B. Look for leaks in the system.
C. Calibrate the oxygen analyzer.
A. A discrepancy between the delivered FIO2 and the D. Obtain another air-oxygen blender.
set FIO2 has developed.
B. The oxygen pressure might be 10 psig greater
than that of the compressed air. IIB3a
C. A leak has occurred somewhere in the system. 164. The diagram in Figure 4-3 illustrates the graph gener-
D. The humidifier water level is low. ated when a nitrogen analyzer was exposed to high and
low nitrogen calibration gases.
IIB1f(1)
Which of the following statements accurately de-
160. While an oropharyngeal airway is being inserted into scribe(s) the outcome of the calibration process?
an apparently unconscious patient, the patient sud-
denly beings coughing violently. What should the CRT I. A one-point calibration has been successfully per-
do to ensure a patent airway in this patient? formed.
II. The slope of the analyzer has been established.
A. Spray the back of the throat with lidocaine and III. The linearity of the analyzer has been estab-
reinsert the oropharyngeal airway. lished.
B. Perform an emergency cricothyroidotomy. IV. The balance of the analyzer has been established.
C. Withdraw the oropharyngeal airway and insert a
nasopharyngeal airway. A. I only
D. Continue the insertion of the oropharyngeal air- B. II, IV only
way, because this response is normal. C. I, III only
D. II, III, IV only

222 Chapter 4: Equipment

 IIB2h(4)
168. A CRT is performing a series of arterial blood-gas

Measured Value
analyses on three patients and notes that the last three
80 samples have consistently provided elevated PaO2 lev-
els of 120 torr, 132 torr, and 138 torr, respectively. Pre-
vious sampling had demonstrated that all three of these
patients had PaO2 values between 70 torr and 80 torr.
Which of the following factors might account for this
phenomenon?
A. Too long a delay between sampling and analysis
might have taken place.
B. Air bubbles are being introduced into the samples.
C. Excessive amounts of blood are being analyzed.
0 D. The specimen is not being iced after procurement.
80
Test Signal Value IIB3b
169. Which of the following techniques can be used to per-
Figure 4-3: Graph illustrating data points of high and low
calibration gases from a nitrogen gas analyzer. form quality control of a body plethysmograph?
I. biologic controls
IIB1f(3) II. isothermal lung analog
165. What should be done with the outer cannula of a III. comparison with gas dilution
tracheostomy tube when the inner cannula is being IV. comparison with radiologic lung volumes
cleaned? A. I only
A. removed for cleaning first B. I, III only
B. replaced with a tracheal button C. II, III, IV only
C. left in place D. I, II, III, IV
D. replaced with a sterile cannula
IIB2b
IIB1h(2)
170. The CRT enters the room of a patient who is receiv-
166. A Bird high-flow oxygen blender set at 40% is deliver- ing oxygen therapy from an appliance that is attached
ing 80 liters/minute to a CPAP system. Oxygen-line to a wick humidifier and notices little humidity out-
pressure is considerably higher than the air-line pres- put at the patient end. What should the CRT do at this
sure. What will be the result of this pressure difference? time?
A. The delivered FIO2 will decrease below 0.40. I. Check to see whether the unit is plugged into a
B. The delivered FIO2 will increase above 0.40. 120 volt outlet.
C. The delivered FIO2 will remain unchanged at the II. Check the status of the float in the reservoir
current flow rate. system.
D. The delivered FIO2 will decrease if the flow rate III. Determine whether the temperature probe wire is
drops below 40 liters/minute. loose or broken.
IV. Examine the reservoir feed system.
IIB2e(1)
A. II, IV only
167. A patient is being mechanically ventilated with a Ben-
B. I, III only
nett 7200ae in the SIMV mode. Her mechanical rate is
C. II, III, IV only
set at 6 breaths/minute, while her spontaneous rate is
D. I, II, III, IV
10 breaths/minute. As the CRT administers an in-line
aerosol treatment powered by a flow meter, he notices
IIB1h(4)
that the ventilator repeatedly converts to apnea venti-
lation. The best solution to this problem is 171. How is the transcutaneous partial pressure of oxygen
(PtcO2) influenced by hypotension?
A. Discontinuing the treatment.
B. Powering the nebulizer with the ventilator nebu- A. The PtcO2 decreases.
lizer source. B. The PtcO2 increases.
C. Readjusting the apnea settings. C. The PtcO2 fluctuates.
D. Reducing the flow rate to the nebulizer. D. The PtcO2 correlates well with the PaO2.

Chapter 4: Equipment 223

IIB2h(4) A. Use biologic controls when calibrating the instru-
172. While obtaining an SpO2 reading from a pulse oxime- ment.
ter with a finger probe attached to a patient, the CRT B. Use a calibration syringe.
cannot obtain an SpO2 reading or a heart rate. Which C. Fill the bellows with air, seal the openings, and
of the following corrective measures would be appro- place a weight on the bellows.
priate at this time? D. Fill the bellows with air, maintain the opening, and
observe the movement of the pen on the chart paper.
I. stopping the patient from moving excessively
II. shielding the probe from ambient light IIB1f(4)
III. massaging the site for about 30 seconds
176. The CRT is unable to visualize the larynx of a neonate
IV. repositioning and correctly applying the sensor
that she is attempting to intubate with a No. 1 Macintosh
A. I, II only blade in the delivery room. What should she do next?
B. II, III, IV only
A. Use a No. 1 Miller blade instead.
C. I, III, IV only
B. Ask someone to provide laryngeal pressure.
D. I, II, III, IV
C. Try a larger Macintosh blade.
D. Ventilate with a Mapleson and mask until some-
IIB3a one else can try the intubation.
173. The blood-gas laboratory at a hospital is concerned
about the accuracy of arterial PO2 values in a patho- IIB1i(1)
logic range. Which of the following methods of PO2
177. A Siemens Servo 900C has just been cleaned, and a
electrode calibration would help reduce the labora-
new circuit has been attached. While evaluating venti-
tory’s concern?
lator performance, the CRT notices that the airway
A. one-point calibration using a gas containing 20% pressure reading is zero. What could be the reasons for
oxygen this situation?
B. one-point calibration using a gas containing 12%
A. a loose tube between the inspiratory channel and
oxygen
the pressure transducer
C. two-point calibration using two gases containing
B. too high a set working pressure
0% and 20% oxygen
C. insufficient gas supply
D. two-point calibration using two gases containing
D. an out-of-position safety valve
0% and 12% oxygen
IIB2f(2)
IIB2a(2)
178. An adult male has just been intubated with an 8.0 mm
174. A patient is receiving oxygen-enriched aerosol ther-
I.D. oral ET tube. After inflating the cuff to 30 cm
apy. The setting on the jet nebulizer is 40%; however,
H2O, a significant leak is noted with inflating pres-
when the CRT analyzed the patient’s FIO2, it was
sures as low as 25 cm H2O. The X-ray reveals that the
found to be 0.5. Which of the following reasons could
tube is in the proper position, but the inflated cuff is
have accounted for this discrepancy?
barely making contact with the tracheal wall. What
I. The oxygen flow rate must have been reduced. should be done at this time?
II. Extra lengths of large bore tubing might have
A. Extubate the patient and reintubate with a larger-
been added to the system.
sized tube.
III. Condensate might be collecting in the delivery
B. Increase the cuff pressure in order to ensure a
circuit.
minimal seal.
IV. The air-entrainment port might have been opened
C. Ventilate the patient with a larger volume in order
more widely.
to compensate for the leak.
A. I, II only D. Use high-frequency jet ventilation to avoid high
B. II, IV only inflating pressures.
C. III, IV only
D. II, III only IIB1h(2)
179. A diaphragm type, portable air compressor is being
IIB1n used to power a ventilator. The compressor is not pow-
175. The CRT suspects that a bellows-type spirometer has erful enough to meet the ventilator’s flow demand.
developed a leak. How can the CRT determine the sta- What is the most serious problem that might result
tus of the bellows? from this action?

224 Chapter 4: Equipment

 A. The peak flow on the ventilator will be inaccurate
because of a decrease in flow from the compres-
sor.
B. “Wet air” might be delivered to the ventilator.
C. The compressor motor might be damaged.
D. The patient could contract a nosocomial infection
secondary to contaminated air.

IIB3a
180. The CRT is preparing to calibrate a helium gas ana-
lyzer before performing a closed circuit, helium dilu-
tion, FRC determination. Which of the following
conditions must be present during the calibration of Figure 4-4: Probe of a pulse oximeter that is attached to a
the helium analyzer? patient’s finger.

I. The water vapor absorber must be removed dur-

ing calibration.
IIB1i(1)
II. The carbon dioxide scrubber must be connected 183. A CRT is summoned to the bedside of a patient who is
during calibration. receiving an IPPB treatment with a Bird Mark VII pow-
III. A sample of room air can be used in the calibra- ered with a diaphragm-type air compressor. The system
tion process. pressure gauge is not achieving the desired 20 cm H2O;
IV. A sample of gas containing 10% helium can be thus, the patient is not receiving an effective treatment.
used in the collection process. Upon further investigation, the CRT finds that the source
pressure generated from the compressor is 32 psig.
A. I, III only Based on the information provided, which of the fol-
B. II, IV only lowing causes could be responsible for this condition?
C. II, III, IV only
D. I, II, III, IV A. The Bird Mark VII has been inadvertently set on
100% oxygen.
IIB2h(1) B. The compressor inlet filter is severely obstructed.
C. The compressor is not properly grounded.
181. The CRT enters the room of a patient who is wearing a
D. The Bird Mark VII is out of calibration and needs
simple mask attached to a pulse-dose oxygen-delivery
preventive maintenance.
device set in the pulse mode to deliver a flow rate of
4 liters/min. What should the CRT do at this time?
IIB1h(4)
A. Remove the simple mask and place a cannula on 184. When applying the finger probe of a pulse oximeter to
the patient. a grossly obese patient, the CRT cannot align the tip of
B. Increase the flow rate to 5 liters/min. any of the patient’s fingers between the light-emitting
C. Increase the flow rate to 5 liters/min. and set the diodes and the photodetector of the probe. What
device in the continuous flow mode. should the CRT do at this time?
D. Nothing needs to be done, because the system is
set up appropriately. A. Use the finger that provides the best fit.
B. Apply adhesive tape around the probe to secure it
IIB2h(4) to one of the fingers.
C. Use a different style probe.
182. The CRT has applied the finger probe of a pulse
D. Obtain an arterial blood-gas sample.
oximeter to a patient, as pictured in Figure 4-4. What
action needs to be taken?
IIB2h(1)
A. Reverse the probe, because it is positioned upside 185. While checking an H cylinder used as a backup by a
down. home-care patient who is receiving oxygen therapy via
B. Switch the finger probe to a different finger. an oxygen concentrator, the CRT turns on the cylinder
C. Switch the finger probe to the left hand. valve and hears a constant hissing sound while the
D. Align the tip of the finger with the LED and pho- Bourdon gauge flow meter continuously registers 0
todiode. liter/min. What action should the CRT take at this time?

Chapter 4: Equipment 225

 A. Replace the H cylinder. A. Nothing needs to be done, because everything is
B. Replace the regulator. functioning properly.
C. Apply a soap solution to the connections to iden- B. The resistor is too close to the patient and needs to
tify the leak. be moved.
D. Turn on the flow meter to determine whether the C. A water column threshold resistor should be in-
hissing sound stops. stalled in place of the weighted ball.
D. The weighted-ball device needs to be placed in a
IIB3a vertical position.
186. The graph illustrated in Figure 4-5 was obtained dur-
ing the calibration of a helium analyzer. IIB2f(2)
188. While checking a mechanically ventilated male pa-
He Analyzer tient, the CRT notices a leak around the cuff of the oral
10% endotracheal tube. The CRT adds several cubic cen-
timeters of air 1 cc at a time, observing no change in
the size of the leak. She notes that the tube is taped at
Measured Value

8% 20 cm at the corner of the mouth and that the pilot bal-

loon has air in it. What should she do?

6% A. Deflate the cuff, advance the tube 2 to 3 cm, and

reinflate the cuff.
B. Try adding a little more air to effect a seal.
4% C. Increase the volume delivered by the ventilator to
compensate for the leak.
D. Replace the endotracheal tube, because the cuff
probably leaks.
2%

IIB2h(1)
189. A major problem encountered with the use of air-
2% 4% 6% 8% 10% oxygen blenders is
Test Signal Value
A. the loss of oxygen and air-line pressures.
Theoretical Equal Value Point B. the provision of inadequate humidification at high
Connected Points of Actual Measured Values flow rates.
C. the lack of an alarm system.
Figure 4-5: Graph illustrating data points that are obtained
during calibration of a helium gas analyzer. D. the fluctuation in the oxygen percentage as back
pressure increases.
Which of the following statements accurately describe as-
pects of the calibration process? IIB1h(1)
I. The helium analyzer is linear. 190. The CRT is transporting a patient who is receiving
II. The helium analyzer is not balanced. oxygen via a simple mask at 6 liters/min., operating
III. The slope of the helium analyzer has been estab- off of an E cylinder with a regulator that uses a Bour-
lished. don gauge flow meter. If the humidifier imposes a
IV. Random errors are taking place during calibration. greater-than-normal resistance to the oxygen flow,
what will be the consequence?
A. II, IV only
B. I, III only A. The gas will have a higher relative humidity.
C. I, IV only B. The oxygen flow meter will indicate a flow rate
D. I, II, IV only greater than 6 liters/min.
C. The FIO2 will decrease.
IIB1i(2) D. The E cylinder will empty faster.
187. The CRT is visiting the home of a mechanically venti-
lated patient when he notices that the patient has a 5-cm IIB3a
H2O, weighted-ball threshold resistor lying horizontally 191. The CRT is calibrating a nitrogen analyzer, and the
on the bed (while attached to the exhalation port). The calibration data are depicted on the graph in Figure
pressure manometer falls to 5 cm H2O when the patient 4-6.
exhales. What should the CRT do at this time?

226 Chapter 4: Equipment

 6.0 Fr. chest tube connected to a Heimlich valve. The
CRT cannot determine whether the patient has an on-
going leak or not. How can the presence of an ongoing
Measured Value leak be ascertained?
A. The sound of air continuously moving through
the valve indicates an ongoing leak.
B. Equal bilateral chest-wall movement can be ob-
60 served.
C. Observe the chest wall on the same side rise after
clamping the chest tube with a hemostat.
D. Watch for bubbling after immersing the valve un-
der water.

IIB2h(1)
0 194. While riding in an ambulance with a patient who is re-
80 ceiving oxygen from an E cylinder, the CRT notices
Test Signal Value the liter flow on a Thorpe tube flow meter indicates 0
liter/min. The Bourdon pressure gauge indicates 2,000
Figure 4-6: Graph illustrating data points that are obtained psig as the E-cylinder is positioned upright and is se-
during calibration of a nitrogen gas analyzer. cured to the wall of the ambulance. What should the
Which of the following statements accurately describe CRT do at this time?
the events occurring during calibration? A. Turn on the cylinder valve.
I. The linearity of the nitrogen analyzer has not been B. Position the cylinder horizontally.
established. C. Check the oxygen equipment for a leak.
II. The instrument’s balance has not been achieved. D. Check the oxygen equipment for an obstruction.
III. The slope of the nitrogen analyzer has been es-
tablished. IIB1a(2)
IV. A one-point calibration has been performed. 195. The CRT is working with a patient who is receiving
A. I, II only 35% oxygen from a Venturi mask and notices that the
B. III, IV only patient has thickening secretions and increased, pro-
C. I, II, III only ductive coughing. Which of the following actions
D. I, II, III, IV would be appropriate at this time?
A. switching to a jet nebulizer operating an aerosol
IIB2a(1) mask at 60%
192. A patient is receiving oxygen therapy via a partial re- B. performing endotracheal suctioning
breathing mask operating at 10 liters/min. The CRT C. increasing the oxygen concentration
notices that the reservoir bag does not completely refill D. adding aerosol through the aerosol collar, which is
during exhalation. Which of the following actions is attached to the air-entrainment port
appropriate to take at this time?
I. Increase the liter flow of oxygen. IIB3b
II. Check the bag for a leak. 196. How should the CRT check the speed of a recorder
III. Examine the oxygen tubing for a kink or an ob- time sweep of a volume-displacement spirometer?
struction. A. with an X-Y plotter
IV. Ensure that the mask fits snugly on the patient’s face. B. with the chart (recording) paper
A. I, IV only C. with a stopwatch
B. II, III only D. with a large-volume syringe
C. III, IV only
D. II, III, IV only IIB2o
197. The CRT notices the level of the water seal in a two-
IIB1p bottle pleural drainage system fluctuate when the suc-
193. The CRT enters the emergency department and sees a tion is momentarily turned off. What action needs to
patient who has a pneumothorax being drained with a be taken at this time?

Chapter 4: Equipment 227

 A. No action is necessary, because this response is IIB1a(1)
normal. 200. The CRT is about to place a disposable nonrebreathing
B. The level of the water seal is low, and water needs mask on a patient who has had carbon monoxide ex-
to be added to the bottle. posure. How should the oxygen flow rate be set in re-
C. The chest tube leading to the system is obstructed lation to the reservoir bag deflation during inspiration?
and needs replacing.
D. The CRT needs to clamp the chest tube with a he- A. The reservoir bag should be allowed to com-
mostat and suture the point of insertion of the pletely deflate.
chest tube at the chest wall. B. The reservoir bag should remain completely filled.
C. The reservoir bag should deflate by only one-third.
IIB3a D. The reservoir bag should not completely deflate.
198. The CRT is performing quality control on a blood-gas
analyzer. The data from the three electrodes (O2, CO2,
IIB2c
and pH) are displayed as follows: 201. The CRT is analyzing the FIO2 of a jet nebulizer set at
40% oxygen used to deliver aerosol therapy to a patient
O2 Electrode CO2 Electrode pH Electrode via an aerosol mask. The jet nebulizer is set to deliver
40% oxygen. The patient is capable of ambulating and
MEAN: 100 torr MEAN: 40 torr MEAN: 7.40 torr
prefers to move around; consequently, she has about 18
+2 S.D.: 104 torr +2 S.D.: 43 torr +2 S.D.: 7.415 torr
–2 S.D.: 96 torr –2 S.D.: 37 torr –2 S.D.: 7.385 torr feet of aerosol tubing extending from the nebulizer out-
let to the aerosol mask. The CRT analyzes the FIO2 to
Run Run Run be 0.50. What should the CRT do in this situation?
Number Recording Number Recording Number Recording
A. Increase the oxygen liter flow.
1 103 1 42 1 7.419 B. Replace the jet nebulizer with two jet nebulizers
2 95 2 41 2 7.420 in tandem.
3 104 3 39 3 7.423 C. Replace the aerosol setup with an air entrainment
4 100 4 42 4 7.418 mask.
5 101 5 38 5 7.421 D. Check the system for leaks.
6 96 6 40 6 7.417
7 98 7 39 7 7.416
8 97 8 38 8 7.415
IIB2a(1)
9 101 9 40 9 7.419 202. Upon entering the room of a patient who is receiving
10 100 10 42 10 7.414 oxygen at 6 liters/min. by way of a partial rebreathing
11 102 11 38 11 7.418 mask, the CRT notices that the reservoir bag does not
12 98 12 39 12 7.420 completely fill when the patient exhales. Which of the
14 99 14 41 14 7.420 following actions is appropriate to correct this situation?
15 103 15 37 15 7.421
A. switching to a nonrebreathing mask
B. checking to see whether the one-way valve be-
Which of the following interpretations can be made tween the mask and the bag is stuck
based on these quality-control data? C. ensuring that the humidifier jar is full
A. All three electrodes are in control. D. increasing the oxygen flow rate
B. Only the pH electrode is out of control.
C. The O2 and CO2 electrodes are out of control, but IIB3b
the pH electrode is in control. 203. The CRT is asked to check the frequency response of
D. The CO2 electrode is the only electrode in control. a spirometer, because the device is suspected to be in-
accurate. What should the CRT use to determine the
IIB1m spirometer’s frequency of response?
199. The CRT is using an aneroid manometer to measure A. stopwatch
rapidly changing ventilatory pressures during patient B. sinusoidal pump
breathing. Which of the following statements best de- C. rotameter
scribes the reliability of this device under these conditions? D. calibrated syringe
A. The PIP will be overestimated, and the baseline
pressure will be underestimated. IIB1p
B. The PIP will be underestimated, and the baseline 204. Which of the following pleural drainage systems can
pressure will be overestimated. operate directly from wall suction?
C. Both pressures will be overestimated.
D. Both pressures will be underestimated. I. one-bottle system
II. two-bottle system
228 Chapter 4: Equipment
 III. three-bottle system C. This spirometer is not reliable.
IV. four-bottle system D. The spirometer needs to be recalibrated.
A. II only
B. III only IIB2a(1)
C. I, II only 208. The CRT sees an unconscious, spontaneously breath-
D. III, IV only ing patient wearing a simple oxygen mask, strapped in
place and operating at 7 liters/min. What action should
IIB2a(1) be taken at this time?
205. The CRT enters the room of a patient who is receiving A. No action is necessary, because the patient and
oxygen via a nasal cannula at 4 liters/min. with hu- oxygen appliance are fine.
midification. The pop-off valve on the bubble humidi- B. The mask should be unstrapped and allowed to
fier is sounding. What actions would be appropriate rest on the patient’s face.
for the CRT to take at this time? C. The oxygen flow rate should be increased to 10
liters/min.
A. adding water to the humidifier
D. A nasal cannula operating at 2 liters/min. should
B. reducing the liter flow
be used.
C. checking for kinked oxygen tubing
D. checking the system for loose connections
IIB1a(1)
IIB2o 209. The CRT is setting up a partial rebreathing mask on a
patient. How should the flow rate of oxygen be set in re-
206. The CRT notices the water level in the water-seal bot-
lation to the reservoir bag deflation during inspiration?
tle of a three-bottle pleural drainage system remain
constant as the patient continues breathing while the A. The reservoir bag should remain half filled during
suction to the drainage system is momentarily turned inspiration.
off. What action needs to be taken at this time? B. The reservoir bag should remain one-third filled
during inspiration.
A. Water needs to be added to the water-seal bottle.
C. The reservoir bag should be allowed to com-
B. The water-seal bottle needs to vent to the atmosphere.
pletely empty during inspiration.
C. The chest tube needs to be replaced.
D. The reservoir bag should remain completely filled
D. No action is necessary, because this response is
during inspiration.
normal.
IIB3b
IIB3b
210. The CRT suspects that a pressure transducer is providing
207. A CRT has been performing quality control on
erroneous measurements, because it might be out of cali-
a spirometer by using biologic controls. The data
bration. How should he calibrate the pressure transducer?
obtained from one biologic control subject is listed as
follows: A. zeroing the transducer
B. obtaining measurements from a normal subject
Biologic Control: WWW
C. connecting the pressure transducer to a mercury
Date Actual FEV1 (L) Actual FVC (L) manometer
D. sending a known electric current through the
1-20-00 3.66 4.16 Wheatstone bridge
2-20-00 3.79 4.26
3-20-00 3.67 4.14 IIB3b
4-20-00 3.54 4.05
5-20-00 3.76 4.22 211. The CRT is asked to perform quality control on a body
6-20-00 3.65 4.15 plethysmograph. Which of the following forms of
7-20-00 3.70 4.20 quality control can be performed on this device?
MEAN: 3.68 4.17
S.D.: 0.08 0.07
I. using a U-shaped water manometer
PREDICTED FEV1: 3.38 L II. performing an isothermal lung analog
PREDICTED FVC: 3.98 L III. comparing with gas dilution volumes
IV. using a flow transducer

Which of the following interpretations can be made A. II only

based on the data obtained from this biologic control? B. I, IV only
C. II, III only
A. These biologic control data are poor. D. I, III, IV only
B. These biologic control data are acceptable.

Chapter 4: Equipment 229

 STOP
You should have completed 100 questions referring to the matrix sections IIB1 to IIB3. Use the Entry-Level Exam-
ination Matrix Scoring Form (Table 4-5) referring to equipment sections IIB1, IIB2, and IIB3. Be sure to review the
matrix items, study the rationales, and read the references. Again, refer to the Equipment portion of the Entry-Level
Examination Matrix found in Table 4-6 on pages 231–232.
Table 4-5: Equipment—Entry-Level Examination Matrix Scoring Form for Content Areas IIB1, IIB2, and IIB3

Entry-Level Equipment Equipment Items Equipment Content

Examination Content Area Item Number Answered Correctly Area Score

IIB1. Assemble, check for proper 114, 117, 118, 119, 120, 123, 124, 127,
equipment function, and 128, 129, 130, 131, 132, 133, 134, 136,
identify malfunction of 137, 138, 141, 142, 145, 147, 148, 150, __  100 = ____%
equipment. 151, 152, 153, 158, 160, 161, 165, 166, 47
171, 175, 176, 177, 179, 183, 184, 187,
190, 193, 195, 199, 200, 204, 209

IIB2. Take action to correct 112, 113, 115, 116, 121, 122, 125, 126,
malfunctions of equipment. 135, 139, 140, 143, 144, 146, 149, 154, __  100 = ____%
___
155, 156, 157, 159, 162, 163, 167, 168, __  100 = ____% 111
170, 172, 174, 178, 181, 182, 185, 188, 41
189, 192, 194, 197, 201, 202, 205, 206,
208

IIB3. Perform quality-control 164, 169, 173, 180, 186, 191, 196, 198, __  100 = ____%
procedures. 203, 207, 210, 211 12

230 Chapter 4: Equipment

 Table 4-6: NBRC Certification Examination for Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
N

N
(1) pneumatic, electric, microprocessor,
II. Select, Assemble, and fluidic x
(2) non-invasive positive pressure x
Check Equipment for Proper f. artificial airways x
Function, Operation and (1) oro- and nasopharyngeal airways x
Cleanliness (2) oral, nasal and double-lumen
endotracheal tubes x
SETTING: In any patient care (3) tracheostomy tubes and buttons x
setting, the respiratory therapist (4) intubation equipment [e.g.,
selects, assembles, and assures laryngoscope and blades, exhaled
cleanliness of all equipment used CO2 detection devices] x
in providing respiratory care. The g. suctioning devices [e.g., suction
therapist checks all equipment catheters, specimen collectors,
and corrects malfunctions. oropharyngeal suction devices] x
h. gas delivery, metering and clinical
analyzing devices x
B. Assemble and check for proper equipment (1) regulators, reducing valves,
function, identify and take action to connectors and flow meters, air/
correct equipment malfunctions, and oxygen blenders, pulse-dose systems x
perform quality control. 9 14 0 (2) oxygen concentrators, air
1. Assemble, check for proper function, and compressors, liquid-oxygen systems x
identify malfunctions of equipment: (3) gas cylinders, bulk systems and
a. oxygen administration devices manifolds x
(1) nasal cannula, mask, reservoir (4) capnograph, blood gas analyzer
mask (partial rebreathing, non- and sampling devices, co-oximeter,
rebreathing), face tents, transcutaneous O2/CO2 monitor,
transtracheal oxygen catheter,
pulse oximeter x
oxygen conserving cannulas x
(5) CO, HE, O2, and specialty gas
(2) air-entrainment devices,
analyzers x
tracheostomy collar and T-piece,
i. patient breathing circuits
oxygen hoods and tents x
(1) IPPB, continuous mechanical
(3) CPAP devices x
ventilation x
b. humidifiers [e.g., bubble, passover,
(2) CPAP, PEEP valve assembly x
cascade, wick, heat moisture exchanger] x
j. aerosol (mist) tents x
c. aerosol generators [e.g., pneumatic
k. incentive breathing devices x
nebulizer, ultrasonic nebulizer] x
l. percussors and vibrators x
d. resuscitation devices [e.g., manual
m. manometers—water, mercury and
resuscitator (bag-valve), pneumatic
aneroid, inspiratory/expiratory pressure
(demand-valve), mouth-to-valve mask
meters, cuff pressure manometers x
resuscitator] x
n. respirometers [e.g., flow-sensing
e. ventilators x
devices (pneumotachometer), volume
displacement] x

*The number in each column is the number of item in that content area and the cognitive level contained in each
examination. For example, in category I.A., two items will be asked at the recall level, three items at the application level,
and no items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the
respective column (Recall, Application, and Analysis).

Chapter 4: Equipment 231

Table 4-6: (Cont.)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
IS

IS
N

N
N

N
o. electrocardiography devices [e.g., ECG h. gas delivery, metering and clinical
oscilloscope monitors, ECG machines analyzing devices x
(12-lead), Holter monitors] x (1) regulators, reducing valves,
p. vacuum systems [e.g., pumps, connectors and flow meters, air/
regulators, collection bottles, pleural oxygen blenders, pulse-dose
drainage devices] x systems x
q. metered dose inhalers (MDIs), (2) oxygen concentrators, air
MDI spacers x compressors, liquid-oxygen systems x
r. Small Particle Aerosol Generators (3) gas cylinders, bulk systems and
(SPAGs) x manifolds x
2. Take action to correct malfunctions of (4) capnograph, blood gas analyzer
equipment: and sampling devices, co-oximeter,
a. oxygen administration devices transcutaneous O2 /CO2 monitor,
(1) nasal cannula, mask, reservoir mask pulse oximeter x
(partial rebreathing, non-rebreathing), i. patient breathing circuits x
face tents, transtracheal oxygen (1) IPPB, continuous mechanical
catheter, oxygen conserving cannulas x ventilation x
(2) air-entrainment devices, (2) CPAP, PEEP valve assembly x
tracheostomy collar and T-piece, j. aerosol (mist) tents x
oxygen hoods and tents x k. incentive breathing devices x
(3) CPAP devices x l. percussors and vibrators x
b. humidifiers [e.g., bubble, passover, m. manometers—water, mercury and
cascade, wick, heat moisture exchanger] x aneroid, inspiratory/expiratory pressure
c. aerosol generators [e.g., pneumatic meters, cuff pressure manometers x
nebulizer, ultrasonic nebulizer] x n. respirometers [e.g., flow-sensing
d. resuscitation devices [e.g., manual devices (pneumotachometer), volume
resuscitator (bag-valve), pneumatic displacement] x
(demand-valve), mouth-to-valve mask o. vacuum systems [e.g., pumps,
resuscitator] x regulators, collection bottles, pleural
e. ventilators x drainage devices] x
(1) pneumatic, electric, microprocessor, p. metered dose inhalers (MDIs),
fluidic x MDI spacers x
(2) non-invasive positive pressure x 3. Perform quality control procedures for: x
f. artificial airways a. blood gas analyzers and sampling
(1) oro- and nasopharyngeal airways x devices, co-oximeters x
(2) oral, nasal and double-lumen b. pulmonary function equipment, ventilator
endotracheal tubes x volume/flow/pressure calibration x
(3) tracheostomy tubes and buttons x c. gas metering devices x
(4) intubation equipment [e.g.,
laryngoscope and blades, exhaled
CO2 detection devices] x
g. suctioning devices [e.g., suction
catheters, specimen collectors,
oropharyngeal suction devices] x

232 Chapter 4: Equipment

 Matrix Categories
1. IIA1a(2) 48. IIA1i(1) 95. IIA1f(2) 142. IIB1a(2)
2. IIA1h(3) 49. IIA1a(3) 96. IIA2 143. IIB2g
3. IIA2 50. IIA1a(2) 97. IIA1h(4) 144. IIB2h(1)
4. IIA1b 51. IIA1n 98. IIA1f(1) 145. IIB1q
5. IIA1a(1) 52. IIA1f(4) 99. IIA1f(2) 146. IIB2f(3)
6. IIA1r 53. IIA2 100. IIA1f(4) 147. IIB1a(2)
7. IIA1f(4) 54. IIA1m(1) 101. IIA1g 148. IIB1h(4)
8. IIA1h(5) 55. IIA1a(1) 102. IIA1h(4) 149. IIB2h(2)
9. IIA1a(1) 56. IIA1l 103. IIA1h(1) 150. IIB1c
10. IIA1c 57. IIA1k 104. IIA1h(3) 151. IIB1a(2)
11. IIA1e(1) 58. IIA1a(2) 105. IIA1h(1) 152. IIB1d
12. IIA1g 59. IIA1b 106. IIA1g 153. IIB1f
13. IIA1i(1) 60. IIA1d 107. IIA1i(2) 154. IIB2h(2)
14. IIA2 61. IIA1i(2) 108. IIA1g 155. IIB2i(2)
15. IIA1h(5) 62. IIA1h(4) 109. IIA1h(1) 156. IIB2f(3)
16. IIA1d 63. IIA1c 110. IIA1h(2) 157. IIB2e(1)
17. IIA1b 64. IIA1a(1) 111. IIA1g 158. IIB1a(2)
18. IIA1f(3) 65. IIA1k 112. IIB2e(2) 159. IIB2h(1)
19. IIA1e(2) 66. IIA1h(2) 113. IIB2j 160. IIB1f(1)
20. IIA1h(4) 67. IIA1b 114. IIB1a 161. IIB1h(2)
21. IIA1a(1) 68. IIA1n 115. IIB2m 162. IIB2i(1)
22. IIA1b 69. IIA2 116. IIB2h(3) 163. IIB2h(1)
23. IIA1e(1) 70. IIA1a(1) 117. IIB1a(1) 164. IIB3a
24. IIA1f(2) 71. IIA1i(2) 118. IIB1b 165. IIB1f(3)
25. IIA1q 72. IIA1h(3) 119. IIB1e(1) 166. IIB1h(2)
26. IIA1m(1) 73. IIA1g 120. IIB1h(3) 167. IIB2e(1)
27. IIA1h(4) 74. IIA1f(4) 121. IIB2a(2) 168. IIB2h(4)
28. IIA1j 75. IIA1e(1) 122. IIB2h(4) 169. IIB3b
29. IIA1e(2) 76. IIA1a(1) 123. IIB1h(4) 170. IIB2b
30. IIA1a(1) 77. IIA1h(4) 124. IIB1e(1) 171. IIB1h(4)
31. IIA2 78. IIA1h(1) 125. IIB2e(2) 172. IIB2h(4)
32. IIA1s 79. IIA1f(3) 126. IIB2h(2) 173. IIB3a
33. IIA1a(2) 80. IIA1g 127. IIB1a(2) 174. IIB2a(2)
34. IIA1b 81. IIA1a(2) 128. IIB1i(2) 175. IIB1n
35. IIA1f(1) 82. IIA1m(1) 129. IIB1c 176. IIB1f(4)
36. IIA1m(1) 83. IIA1i(2) 130. IIB1f(2) 177. IIB1i(1)
37. IIA1l 84. IIA1h(2) 131. IIB1h(5) 178. IIB2f(2)
38. IIA1a(3) 85. IIA1a(2) 132. IIB1k 179. IIB1h(2)
39. IIA1b 86. IIA1d 133. IIB1a(2) 180. IIB3a
40. IIA1a(2) 87. IIA2 134. IIB1e(2) 181. IIB2h(1)
41. IIA1k 88. IIA1h(4) 135. IIB2h(4) 182. IIB2h(4)
42. IIA1h(2) 89. IIA1h(1) 136. IIB1h(4) 183. IIB1i(1)
43. IIA1f(4) 90. IIA1a(2) 137. IIB1c 184. IIB1h(4)
44. IIA1d 91. IIA2 138. IIB1a(2) 185. IIB2h(1)
45. IIA1h(5) 92. IIA1h(4) 139. IIB2a(2) 186. IIB3a
46. IIA1a(2) 93. IIA1d 140. IIB2f(2) 187. IIB1i(2)
47. IIA1g 94. IIA1f(1) 141. IIB1e(1) 188. IIB2f(2)

Chapter 4: Equipment 233

189. IIB2h(1) 195. IIB1a(2) 201. IIB2c 207. IIB3b
190. IIB1h(1) 196. IIB3b 202. IIB2a(1) 208. IIB2a(1)
191. IIB3a 197. IIB2o 203. IIB3b 209. IIB1a(1)
192. IIB2a(1) 198. IIB3a 204. IIB1p 210. IIB3b
193. IIB1p 199. IIB1m 205. IIB2a(1) 211. IIB3b
194. IIB2h(1) 200. IIB1a(1) 206. IIB2o

234 Chapter 4: Equipment

 Equipment Answers, Analyses, and References
NOTE: The references listed after each analysis are numbered and keyed to the reference list located at the end of this sec-
tion. The first number indicates the test. The second number indicates the page where information about the question
can be found. For example, (1:219, 384) means that on pages 219 and 394 of reference number 1, information about
the question will be found. Frequently, you must read beyond the page number indicated to obtain complete infor-
mation. Therefore, reference to the question will be found either on the page indicated or on subsequent pages.

IIA1a(2) tachment of flow meters to wall outlets. Each gas has

1. A. Any low-flow oxygen-delivery device is inappro- specifically shaped connectors that dovetail with a spe-
priate for a COPD patient who is in an acute exacerba- cific wall outlet.
tion. A number of COPD patients tend to hypoventilate (1:724–727), (16:352–355).
when exposed to a moderate or high FIO2. Low-flow
oxygen-delivery devices deliver imprecise FIO2s when IIA2
the patient has an irregular breathing pattern and a
3. A. Iodophors are compounds that use iodine as their
respiratory rate greater than 20 breaths/min. These
active agent. Betadine and other iodophors have an-
variable-performance devices are also inadequate
timicrobial activity by causing alterations within the
when patients have a minute ventilation less than
microbial protein. Iodophors are effective in cold or
around 8 liters/min. and a tidal volume less than 800
lukewarm water, are nonstaining, and are relatively
cc. All of these ventilatory changes make low-flow
nonirritating. Soap and water are not antimicrobial,
(variable-performance) oxygen-delivery systems inap-
while hexachlorophene and glutaraldehyde have toxic
propriate to use on any patient who is experiencing
effects.
these conditions, because the FIO2 delivered tends to
be higher and unstable. (1:44–45).
High-flow (fixed-performance) oxygen-delivery sys-
tems provide precise FIO2s despite changes in the pa- IIA1b
tient’s respiratory rate, tidal volume, and ventilatory 4. B. The Babington (hydronamic or hydrosphere) nebu-
pattern. Therefore, the oxygen-delivery device most lizer is a high-output aerosol-generating device that
appropriate for the patient (acute exacerbation of uses a water-covered, hollow glass sphere with a small
COPD) in this problem is an air entrainment mask. opening, or jet, to produce aerosol particles. The
aerosol particles produced are within the size range of
(1:746, 754–755), (7:417–422), (16:390–391). 1µ to 10µ, with the majority being approximately 3µ to
5µ. The device can be used for long-term aerosol ad-
IIA1h(3) ministration but should be monitored because of its
2. C. Three indexed safety systems are used in conjunc- high output. The medication nebulizer is a small vol-
tion with the delivery of medical gases from com- ume nebulizer and is not used for long-term adminis-
pressed gas cylinders. These safety systems are tration. A mainstream nebulizer is a jet nebulizer and
identified below. indicates that the path of the main flow of gas is
through the aerosol generator. Mainstream nebulizers,
• American Standard Safety System
however, are usually used for medication delivery, and
• Diameter-Indexed Safety System
the majority of particles produced are greater than 5µ.
• Pin-Index Safety System
(5:146–148), (13:120–121), (15:803–809),
The American Standard Safety System uses threaded,
(16:460–461).
high-pressure connections between sizes F through H
or K compressed gas cylinders and their attachments.
The Pin-Index Safety System is used for small, com- IIA1a(1)
pressed gas cylinder sizes AA to E. The pin-index 5. B. The pendant reservoir nasal cannula is designed to
system incorporates yoke-type connections for con- conserve the use of oxygen to patients who require
necting to the cylinder valve stem. The Diameter- long-term, continuous oxygen delivery. The pendant
Index Safety System employs an externally threaded functions as a reservoir, storing about 20 ml of oxygen
body that interfaces a nipple and hex nut for equip- during exhalation. The patient inhales oxygen stored in
ment connections to cylinder regulators or wall flow the pendant during the initial part of inspiration. The
meters. The Quick Connect System provides for the at- amount of oxygen used for each breath increases;

Chapter 4: Equipment 235

 however, the total oxygen flow rate needed to achieve 6. three sizes of endotracheal tubes
a given FIO2 decreases. 7. stylette
8. adhesive tape
Another type of oxygen-conserving device is the nasal
9. lubricant (KY Jelly)
cannula with a reservoir. The reservoir is located be-
10. Magill forceps
low the nose and above the upper lip and holds about
11. syringe
20 ml of oxygen.
12. stethoscope
The lanyard, or lariat, nasal cannula is the traditional 13. Topical anesthetic spray
type of cannula that drapes over the patient’s ears and
(1:594), (16:588)
tightens under the chin. The nasal mask is not designed
to conserve oxygen, although it improves the FIO2.
IIA1h(5)
(1:748–749), (7:409), (16:383–384). 8. A. The gases carbon monoxide (CO) and carbon dioxide
(CO2) absorb infrared radiation. Because CO is used for
IIA1r determining the DLCO, an infrared absorption analyzer
6. C. Children who are younger than two are susceptible is used to measure the difference between the inspired
to contracting bronchiolitis, which is usually caused and exhaled CO gas concentrations during the test.
by the Respiratory Syncytial Virus (RSV) or the
The emission spectroscopy analyzer is a nitrogen ana-
parainfluenza virus. These patients generally receive a
lyzer. The Giesler tube ionizer is a N2 analyzer based
trial regimen of bronchodilators, such as albuterol or
on the principle of emission spectroscopy. Thermal
metaproterenol. The antiviral drug ribavirin (Virazole)
conductivity analyzers incorporate a Wheatstone
is controversial in the treatment of bronchiolitis or in
bridge. Helium gas cools the wires exposed to the sam-
pneumonia that is caused by RSV. Ribavirin is usually
ple chamber to enable more current to flow through
recommended for patients who have
that circuit in the Wheatstone bridge. The amount of
1. an underlying cardiopulmonary condition helium in a gas sample is proportional to the amount of
2. patients who are younger than six weeks old current flowing through the sample side of the Wheat-
3. immunocompromised children stone bridge. A higher helium concentration is then in-
4. patients who require mechanical ventilation dicated on the readout. Thermal conductivity analyzers
5. patients who have severe pneumonitis caused by are used with gas chromatography.
RSV with a PaO2 less than 65 torr and an in-
Gas chromatography relies on gas separation; i.e., a
creasing PaCO2
gas sample is broken down into its constituents. Sepa-
6. patients who have complicating lung disease
rated gases emerge from a separator column at varying
When ribavirin (Virazole) is administered, a pneu- rates. These component gases are then detected by a
matic nebulizer called a small particle aerosol genera- thermal conductivity analyzer.
tor (SPAG) is used. The SPAG unit aerosolizes a 2%
(6:263–268), (11:44–49).
solution continuously for 12 to 18 hours over a course
of three to seven days. A SPAG unit contains a nebu-
lizer and a drying chamber. Each chamber has its own IIA1a(1)
flow meter. The flow meter setting for the nebulizer 9. D. A simple oxygen mask, nasal cannula, and partial
ranges from 6 to 10 liters/min. The drying chamber rebreather mask are classified as low-flow oxygen-
flow meter ranges from 3 to 6 liters/min. Operating delivery devices that only partially meet a patient’s to-
pressure for this system is 25 psig. The delivery de- tal inspiratory gas-flow demand. Room air provides
vices include a mask, an oxyhood, a mist tent, or a me- the remainder of the inspired gas-flow demand. Be-
chanical ventilator. cause the amount of room air inspired can vary with
each tidal volume, a decreased tidal volume will have
(1:697–698), (5:151–153), (13:108–111), (18:188, less room air in proportion to oxygen delivered from
372, 390). the device. Therefore, the FIO2 delivered will increase.
The converse of this statement is also true.
IIIA1f(4)
Similarly, the FIO2 delivered by a low-flow oxygen-
7. D. To perform endotracheal intubation, the following
delivery system will increase when the patient’s venti-
equipment is necessary:
latory rate decreases (and vice-versa). Overall, the
1. oxygen flow meter FIO2 provided by these oxygen devices is inversely re-
2. oxygen tubing lated to the patient’s minute ventilation (V̇E).
3. suction catheters
A Venturi mask (air-entrainment mask) is a high-flow
4. manual resuscitator and mask
oxygen-delivery device. This mask delivers a precise
5. two laryngoscopes with various sizes of blades

236 Chapter 4: Equipment

 FIO2 and flow to the patient, despite changes in the pa- = 10 liters/minute
tient’s ventilatory pattern, tidal volume, and respira-
50 liters/minute  10 liters/minute
tory rate.
= 60 liters/minute
(1:743–751), (5:58–61), (13:66–69), (15:879–885),
Air (liters/minute)  Oxygen (liters/minute)
(16:381–383).
= Total Flow (liters/minute)
IIA1c 60 liters/minute  6 liters/minute
10. B. Titration systems can be set up by driving the neb- = 66 liters/minute
ulizer from either air or oxygen. If the FIO2 desired To check the system, use the following formula:
falls below the capability of the nebulizer in use, the
nebulizer can be operated on air, and oxygen can be ax + by
=c
titrated in to achieve a lower FIO2. If the FIO2 system a+b
desired is greater than 0.40, the nebulizer can be on
oxygen, and additional oxygen can be titrated. This where,
system will enable the desired FIO2 to be achieved, as a = oxygen flow rate (liters/minute)
well as maintaining relatively high flow rates.
x = 1.0 (FIO2 )
Statement I is incorrect, because the system is deliver-
ing approximately 66 liters/minute—far exceeding a b = air flow rate (liters/minute)
normal peak inspiratory flow rate of about 25 to 30 y = 0.21 (room-air FIO2 )
liters/minute. This flow rate can be calculated by first
determining the air-oxygen ratio for 35% using the (6)(1.0) + (60)(0.21) 18.6
= = 0.28
magic box. 6 + 60 66

100% 21% Although statement II would provide 28% oxygen, the

total flow would only be 11 liters/minute. A flow rate
of 11 liters/minute would create a low flow system by
not meeting the patient’s inspiratory demand.
35%
(1:753), (17:20–22).

IIA1e(1)
14 65 11. A. A rotary-driven piston ventilator moves air in an
65 lpm accelerating, then decelerating manner. Although the
= 4.6:1 or  5:1 rotary wheel moves at a constant speed, the piston is
14 lpm connected eccentrically to the wheel by a piston rod,
creating movement that is not constant. Flow gener-
The magic box is used to determine the air-oxygen ra- ated by this device produces a sine wave flow pattern.
tio. Once you know the value of delivered oxygen per- This type of ventilator is also referred to as a noncon-
centage, place this value in the center of the box. By stant flow generator.
subtracting 35% from 100%, the entrained air flow
rate is obtained (100%  35% = 65 liters/minute). A double circuit, rotary-driven piston would produce
Then, the flow rate of the delivered oxygen is calcu- an accelerating flow pattern, because the flow is ap-
lated by subtracting 21% from 35% (35%  21% = 14 plied to a bag or bellows. An example of a mechanism
liters/minute). The air-oxygen ratio becomes approxi- producing a decelerating flow pattern would be a low-
mately 65:14, or 5:1. pressure drive bellows system. A single circuit, linear-
driven piston ventilator and a bellows-driven ventilator
Because the nebulizer is driven from an air source, for (high-pressure drive) are examples of ventilators that
every liter of air delivered by the flow meter, the system produce a square wave (constant flow) flow pattern.
will entrain 5 liters of air per minute. Therefore, a nebu-
lizer operating at 10 liters/minute will entrain 50 liters of (1:857), (13:360).
air per minute for a total output of 60 liters/minute.
IIA1g
5  1 = 6  10 liters/minute = 60 liters/minute
12. A. Suctioning of the mouth and pharynx is best per-
or formed by using a rigid plastic tube called a Yankauer
catheter. This device has a large diameter, enabling the
5  10 = 50 liters/minute  (1  10)
quick removal of secretions or particulate matter. The

Chapter 4: Equipment 237

 Trach Care closed suction system is designed for use closed, the oxygen from the flow meter will merely
on an endotracheal or tracheostomy tube, enabling the flow through the bag and out the tail.
catheter to be used multiple times in a closed system.
The CRT in this situation probably cannot generate ad-
The Coudé catheter is a curved or angled catheter that
equate gas-delivery pressure and tidal volume, because
is used to facilitate suctioning of the left mainstem
the tail is open (allowing gas to escape) and is pre-
bronchus. A modified whistle-tip catheter is a straight
venting the bag from filling adequately. The oxygen
catheter used for tracheal suctioning.
flow rate for these devices should be set between 8 to
(1:616), (13:182), (16:604). 12 liters/min.
(5:252–253), (13:155–156).
IIA1i(1)
13. B. A tube connecting the IPPB device to the exhalation IIA1b
valve is required to supply a gas flow during inspira- 17. B. When gas flows through the inspiratory limb of the
tion. This tubing enables the delivery of inspiratory ventilator tubing into a cascade humidifier (Figure 4-7)
flow to the patient and inhibits patient exhalation dur- and down through the tower, a one-way valve at the
ing inspiration by closing the exhalation valve. bottom of the tower opens to enable the source gas to
(5:202). mix with the water. The gas forces the water to be dis-
placed, raising the water level inside the humidifier
IIA2 and causing some water to enter the diffusion grid. The
diffusion grid increases the air-water interface, thereby
14. B. Ethylene Oxide (ETO) sterilization causes contact
enhancing humidification.
irritation. Any residual gas must be removed after ster-
ilization is complete. Trace gases are removed through
aeration, which might require up to seven days without
the use of an aeration chamber. The other methods do
not require such additional aeration time.
(1:46–47), (16:1064–1065).

IIA1h(5)
15. C. A polarographic electrode and a zirconium cell are
used for rapid oxygen analysis. They are both well
suited for use in exercise testing, which demands
breath-by-breath analysis. These two analyzers mea-
sure the partial pressure of oxygen. Both analyzers are
sensitive to changes in system pressure. If gas flow
through these analyzers is high, pressure inside the an-
alyzers increases, and the reading is adversely af-
fected. Similarly, if either is used in-line with a
positive pressure ventilator, the PO2 reading will be er-
roneous.
Galvanic and paramagnetic oxygen analyzers are not Figure 4-7: A functional diagram of a cascade humidifier.
rapid-response-type analyzers. The paramagnetic type Water should not move up into the cascade tower. A
is used for discrete sampling, and the galvanic variety properly functioning one-way valve at the bottom of
can be employed for continuous sampling. the tower prevents back flow of water into the tower
(5:281–284), (6:262–263), (11:71–73), (13:186–188). toward the gas source. If the one-way valve is defec-
IIA1d tive or missing, water will rise in the tower.

16. C. A flow-inflating manual resuscitator (commonly (5:107–110), (13:95).

used in anesthesia and neonatal respiratory care) re-
quires oxygen flow from the flow meter to inflate the IIA1f(3)
reservoir bag. The reservoir bag has a tail at its back 18. A. A fenestrated tracheostomy tube is often used to
end. The tail is an open communication between the wean a patient from breathing through the stoma. A
bag and the room air (atmosphere). For the bag to fill, fenestrated tube contains an opening (fenestration) on
the tail must be pinched. When the bag has inflated the cephalad aspect of the tube. Air is permitted to
sufficiently, the CRT should compress the bag while flow through this opening into and out of the patient’s
pinching the tail closed. If the tail is not pinched lungs. The cuff should also be deflated while the pa-

238 Chapter 4: Equipment

 tient breathes through the fenestration. More air is al- The arterial oxygen saturation (SaO2) obtained with an
lowed to move through the upper airway as airway re- arterial blood-gas analysis is a calculated value and not
sistance is reduced. a measured value. This method usually renders a
falsely high SaO2 in the case of smoke inhalation.
A fenestrated tracheostomy tube has numerous com-
ponents: an obsturator to facilitate insertion, a de- A pulse oximeter uses only two different wavelengths
cannulation cannula to prevent air from flowing of light and measures only HbO2 and HHb. Any HbCO
through the 15 mm opening, and an inner cannula to in the blood measured via pulse oximetry will be mea-
prevent upper-airway breathing. The inner cannula sured as HbO2. Consequently, pulse oximetry renders
must be inserted if the patient requires mechanical a falsely high HbO2 (SpO2) in situations related to
ventilatory support. Inserting the inner cannula when smoke inhalation.
suctioning the patient through the tracheostomy tube is
Transcutaneous oxygen monitoring senses the partial
also necessary to ensure the suction catheter’s entry
pressure of oxygen dissolved in the blood that is per-
into the patient’s airway.
fusing the skin. This method has no value as a form of
(1:614–615), (5:247), (13:130–131), (16:634). oxygen monitoring in conditions with elevated HbCO.
(5:297–298), (13:175–177), (16:274–275).
IIA1e(2)
19. A. Patients who tend to benefit from NPPV include asth- IIA1a(1)
matics, COPD patients who are experiencing an acute ex-
21. B. A nasal cannula is commonly used to deliver oxygen
acerbation, patients who have pulmonary edema, patients
because it is tolerated well by the patient, easy for the
who have idiopathic hypoventilation syndrome, and
CRT to set up, and inexpensive to purchase for clinical
quadriplegics. These patients either require short-term or
use. A low-flow system, however, should only be used if
long-term ventilatory assistance. Other types of patients
it will provide a consistent and predictable FIO2. The pa-
who usually respond well to NPPV are those who have
tient’s tidal volume should be between 300 ml to 700 ml;
chest wall disease (e.g., kyphoscoliosis) or chronic neu-
the ventilatory frequency should be below 25 per
romuscular disease (e.g., muscular dystrophy).
minute; and the ventilatory pattern should be regular and
NPPV can be used in either an acute care or long-term consistent. The FIO2 with a low-flow system will vary
setting. Patients are not intubated or have a tra- inversely with the patient’s minute ventilation. As a
cheostomy tube in place. Ventilation is provided by guideline, the FIO2 will increase by approximately 4%
way of a nasal mask or face mask. The following types for each liter increase in flow rate. Therefore, 1
of patients tend to not benefit from NPPV: liter/minute will provide approximately 24%, 2
liters/minute will provide approximately 28%, and so
• patients who have copious airway secretions
forth.
• patients who have poor airway control
• patients who have upper-airway obstruction (an ex- Based on this scenario, an air entrainment mask at
ception is obstructive sleep apnea) 28% would be the best device for this patient. An air
entrainment mask at 35% would be approximately
(1:1122–1125), (10:192), (16:616).
equivalent to 4 liters/minute. No indication exists in
the information provided that an aerosol mask deliver-
IIA1h(4) ing particulate water is warranted.
20. C. Because a co-oximeter can measure multiple he-
moglobin variants, including carboxyhemoglobin (1:743–751), (5:54–68), (13:66–69), (15:879–885),
(HbCO), co-oximetry is the oxygenation monitoring (16:381–383).
method of choice for patients who have been exposed
to smoke inhalation and for those who are suspected of IIA1b
having inhaled smoke. A co-oximeter generally uses 22. C. Both the cascade and wick are heated humidifiers
four different wavelengths of light to measure the fol- that are designed to provide a large surface area for
lowing hemoglobin variants: gas-water interface. This design greatly increases the
rate of evaporation and humidification efficiency.
• oxyhemoglobin (HbO2)
These units can be used with adult mechanical ventila-
• deoxyhemoglobin (HHb)
tors or high flows of gas to provide 100% relative hu-
• methemoglobin (MetHb)
midity at Body Temperature (BTPS), while the other
• carboxyhemoglobin (HbCO)
(bubble, bubble jet, and pass-over) provide insufficient
None of the other forms of oxygen monitoring mea- humidification to prevent body humidity deficits.
sure HbCO. Therefore, those forms of oxygen analysis
(1:665), (5:107–12), (13:111, 112), (16:434–435).
have limited value in this clinical situation.

Chapter 4: Equipment 239

IIA1e(1) used for newborns, to 9.0 mm for adults. The Outside
23. A. To change the flow pattern from constant flow Diameter (O.D.) is generally 1 mm larger than the inter-
(square) to decelerating flow or from square to sine nal diameter. The usual size of an endotracheal tube rec-
wave requires either an increase in time to deliver the ommended for adult males is 8.5 to 9.0 mm I.D., and for
volume or an increase in the peak flow. With Ameri- adult females, the recommended size is 8.0 to 8.5 mm
can-made ventilators, it is typical for the peak flow to I.D. Therefore, an 8.5 mm I.D. endotracheal tube is the
be set; therefore, inspiratory time will automatically correct size for the patient considered in this question.
increase—causing an increase in the I:E ratio with no (1:594).
change in the ventilatory rate.
As a general rule, switching from a square flow to a IIA1q
decelerating flow pattern will double the inspiratory 25. B. A spacer, reservoir chamber, or extension tube can
time. Changing from decelerating flow to square flow be added to an MDI to facilitate the delivery and de-
will decrease the inspiratory time by approximately position of aerosolized medication in the lungs. This
one-half. When a change from a square waveform pat- attachment to the MDI requires less coordination on
tern to a sine wave pattern is made, the inspiratory time the part of the patient, because the spacer acts as a
will increase by a factor of approximately 1.5. Con- reservoir for aerosol particles from which the patient
versely, changing from sine wave to square wave will can inhale. The patient does not need to concern him-
decrease the inspiratory time by a factor of approxi- self with synchronizing his inspiratory effort with ac-
mately 0.67. Refer to Figure 4-8. tuation of the MDI.
(5:124–125), (13:147–148), (15:810–814).
A.
FLOW IIA1m(1)
26. D. A linear pressure gauge is required, but it must be
capable of recording negative pressures from 0 to
–100 cm H2O. If the gauge is also to be used for mea-
suring the MEP, an ideal gauge should be calibrated in
the positive range from 0 to 300 cm H2O. In general,
TIME the MIP in a normal subject is approximately –80 cm
H2O, and the MEP is in the range of 120 to 135 cm
H2O. A decreased MIP indicates weak muscles of
B. ventilation and might be indicative of a patient’s in-
FLOW ability to be successfully weaned from mechanical
ventilation. An MIP more negative than –20 cm H2O
in 20 seconds is compatible with weaning. A one-way
valve enables the patient to exhale but prevents in-
halation. In this way, the patient’s lung volume will
TI
decrease with each effort, helping to increase the like-
TIME lihood of obtaining a maximal effort. The maximal ef-
fort will be achieved with the patient attempting
Figure 4-8: (A) Illustrates square waveform time tracing. inhalation from residual volume. The test should be
(B) Demonstrates overlapped square-wave and sine-wave
flow time tracings. Note that switching from square pattern continued for 20 seconds or until the patient demon-
to sine-wave pattern causes inspiratory time to increase strates signs of significant respiratory distress,
(TI). whichever comes first.
With many European-made ventilators where minute (1:825, 971), (6:52–53), (11:141–142), (16:234).
ventilation is set, inspiratory time is typically preset;
therefore, peak flow would increase in order to deliver
IIA1h(4)
the desired volume with no change in the ventilatory
rate. 27. A. According to the AARC Clinical Practice Guidelines
for Pulse Oximetry, pulse oximetry is indicated to mon-
(1:853), (5:346–349), (13:369–370). itor the adequacy of arterial oxyhemoglobin saturation
to therapeutic intervention or to perform a diagnostic
IIA1f(2) procedure, such as bronchoscopy. A pulse oximeter
24. C. Endotracheal tubes are sized according to their Inter- helps titrate supplemental oxygen to relieve hypoxemia
nal Diameter (I.D.). Sizes range from 2.5 mm, which is associated with the bronchoscopy procedure.

240 Chapter 4: Equipment

 (AARC Clinical Practice Guidelines for Pulse The simple oxygen mask and the nonrebreathing mask
Oximetry), (1:359–361), (10:96–98), (13:191–195), can be used in many of the same situations. Often, the
(16:310–312). difference among these three masks comes down to the
FIO2 needs of the patient. A simple mask provides a
IIA1j moderate FIO2 (0.3 to 0.45), and the nonrebreathing
28. B. Mist tents are plastic enclosures that provide a rea- mask delivers moderate to high FIO2s (0.5 to greater
sonably high aerosol output along with supplemental than 0.9).
oxygen. They are not suitable for delivering a precise (1:745–746, 750–751), (7:414–417), (16:387–389).
and constant FIO2, because many sources of leaks are
present. For example, sides of the canopy often be- IIA2
come loose after being tucked under the mattress, and
31. C. The mask, valve assembly, and resuscitation bag must
the enclosure is often invaded by health-care personnel
be mechanically cleaned to remove all of the debris from
who are attending to the patient and by parents who
external surfaces. The equipment can then be processed
are playing with or touching the child. The capacity of
either by sterilization or by high-level disinfection.
a mist tent is large, which also makes a precise and
constant FIO2 difficult to achieve. These devices are Glutaraldehyde immersion for three hours constitutes
useful for children who have croup (laryngotracheo- sterilization, because by that time this process be-
bronchitis) and cystic fibrosis because of the high comes sporicidal. In 10 minutes, glutaraldehyde kills
aerosol output that they generate. vegetative bacteria, M. tuberculosis, fungi, and viruses.
Ethylene oxide sterilization requires prolonged aera-
An 18-month-old child is too large for an incubator or
tion time for the mask and resuscitation bag, because
an oxyhood. An aerosol mask would be difficult for
the ethylene oxide gas permeates these materials. If
the 18-month-old to tolerate. The child would likely
aeration of such equipment is inadequate, residual eth-
continually remove the mask.
ylene oxide can cause tissue inflammation and hemol-
(5:78–79), (1:759–760), (13:68), (16:395). ysis. When ethylene oxide combines with water,
ethylene glycol forms. Ethylene glycol is also toxic to
IIA1e(2) tissues. Pasteurization is less effective than glutaralde-
29. B. NPPV is suitable for patients who are experiencing hyde and is not broad-spectrum enough.
an acute exacerbation of COPD, ventilatory failure (1:44–51), (7:713), (13:493–497).
from obstructive sleep apnea, and ventilation failure
from congestive heart failure. NPPV has proved suc- IIA1s
cessful in treating these types of patients, thus avoid-
32. A. The treatment of acute atelectasis depends on the
ing the need to intubate and mechanically ventilate
degree of physiologic compromise that is experienced
them. NPPV is also useful in treating patients who
by the patient. If the degree of physiologic compro-
have been weaned from mechanical ventilation and ex-
mise is minimal, e.g., no respiratory distress and a lack
tubated but who have begun experiencing ventilatory
of significant hypoxemia, the patient might require no
difficulty. Re-intubation has been avoided in many
treatment (especially if the patient is ambulating or is
cases. If in such cases NPPV fails, intubation and me-
anticipated to do so soon). If the patient has no physi-
chanical ventilation can be reinstituted.
ologic compromise but is not expected to be ambula-
NPPV must be administered by either nasal mask or tory soon, therapy directed toward lung re-expansion
full face mask and must never be given to patients who is indicated. Such modalities are indicated for about 48
are intubated. NPPV must also be avoided if patients hours. The goal of the lung-expansion therapy is to re-
have poor control of their upper airway and if patients verse or to prevent the progression of the atelectasis by
have excessive tracheobronchial secretions. Similarly, removing the retained secretions. Therapeutic modali-
patients who are hemodynamically unstable or who ties used to accomplish these ends include encourag-
are uncooperative should avoid being given NPPV. ing the patient to cough, providing aerosol therapy,
providing chest physiotherapy, and providing incentive
(1:895, 982), (10:192, 399), (16:616, 1137).
spirometry.
IIA1a(1) This therapeutic regimen was unsuccessful with the
30. D. A partial rebreathing mask is best suited for emer- patient in this question. According to the AARC Clin-
gency situations and for short-term oxygen therapy de- ical Practice Guidelines for Fiberoptic Bronchoscopy
manding moderate to high FIO2s. A partial rebreathing Assisting, fiberoptic bronchoscopy is indicated when
mask operates at a flow rate ranging from 7 to 10 there is suspicion that secretions or mucous plugs are
liters/min. The FIO2 range provided by this device is causing atelectasis. In this case, bronchoscopy will en-
0.35 to 0.5. able the direct instillation of mucolytics and lavage of

Chapter 4: Equipment 241

 the right middle lobe. The absence of air bron- (1:665–667), (5:117–118, (13:127–129), (15:798–799),
chograms indicates that the airways are also filled with (16:429–432).
secretions. This condition enhances the likelihood of
success for the bronchoscopy procedure. IIA1f(1)
Air bronchograms are present when the alveoli are 35. A. A properly inserted nasopharyngeal airway or nasal
fluid-filled and when the surrounding airways are air- trumpet will provide a passageway from the external
filled. This condition creates a contrast of densities, nares to the base of the tongue. This device is a soft,
and the airways become visible radiographically. When flexible, rubber or plastic tube used to facilitate naso-
the airways and surrounding alveoli are both either air- tracheal suctioning, insertion of a bronchoscope, or
filled or fluid-filled, no density contrast exists. There- when the placement of an oropharyngeal airway is not
fore, air bronchograms will be absent. possible. Sizes from 26 to 32 French are common in an
adult. The length of the airway is more critical than the
A thoracentesis is a surgical puncture and drainage of diameter, however.
the thoracic cavity. A thoracoscopy is an examination of
the intrapleural space (pleural cavity) via a thorascope. The approximate length needed is determined by mea-
A mediastinoscopy is an examination of the medi- suring the distance from the tip of the nose to the
astinum by means of an endoscope inserted through an tragus of the ear and adding one inch. Figure 4-9 illus-
anterior midline incision just above the thoracic inlet. trates the positioning of a nasopharyngeal airway of
appropriate length.
(AARC Clinical Practice Guidelines for Fiberoptic
Bronchoscopy Assisting, Respiratory Care, (1:647–648), (5:239–240), (13:159), (16:567–568).
38:1173–1178, 1993), (1:622–626), (9:159–160),
(15:853–856), (19:687).
Flange
IIA1a(2)
33. D. An open-top tent is primarily used to provide hu-
midity in the form of an aerosol to a patient. Addition-
ally, the open top enables heat to escape from the
canopy. If the patient requires an oxygen concentration
Trachea
greater than room air, this system is contraindicated.
Esophagus
(1:759–760), (5:78–79), (13:79–80). Nasopharyngeal
Epiglottis Airway
IIA1b Tragus
34. C. Heat-Moisture Exchangers (HMEs) are placed be-
tween the patient’s breathing circuit and the patient.
During the expiratory phase, gas passes through the
HME, heating the hygroscopic medium and causing Figure 4-9: Nasopharyngeal airway extending from exter-
nal nares to the base of the tongue, immediately above the
condensation within the device to occur. Gas is then epiglottis.
heated and humidified during the subsequent inhala-
tion. Most commercially available HMEs are only ca-
pable of providing between 22 and 28 mg/liter of water IIA1m(1)
vapor, which is equivalent to a relative humidity of be- 36. A. A pressure of 700 kilopascals (kPa) is approxi-
tween 50% to 65% at body temperature. When prop- mately equal to 101 psig. Each of the other manome-
erly used, these devices appear to minimize many of ters would be damaged immediately upon attachment.
the problems associated with large reservoir-heated hu- The following table listing pressure equivalents can be
midifiers. This advantage leads to their popularity. The used to determine each conversion factor.
following criteria for their use, however, should be fol-
Equivalents of 1 ATM
lowed: (1) use only on ventilatory circuits or anesthesia
circuits where the flow is intermittent; (2) use for a 760 mm Hg
short term (24 to 48 hours); (3) the patient should have 29.9 in. Hg
a normal temperature; (4) the patient should be ade- 1,034 cm H2O
quately hydrated; (5) the patient should not require hu- 101.3 kPa
midity for retained secretions; (6) the patient should not 14.7 psig
be receiving low tidal volumes; and (7) patients should
not be experiencing large leaks from the airway.

242 Chapter 4: Equipment

 Statement I: manometer calibrated in kPa from 0 IIA1a(3)
to 700 kPa 38. A. Mask CPAP was developed by Sullivan in the early
101.3 kPa 1980s and has since become the treatment of choice
= 6.89 kPa/psig  50 psig = 345 kPa for many patients who are suffering from obstructive
14.7 psig sleep apnea. Mask CPAP has replaced tracheostomy as
700 kPa the preferred mode of treatment in moderate to severe
= 101.6 psig cases. A soft, pliable mask that is attached to a CPAP
6.89 kPa/psig device is worn by the patient over the nose during
This manometer would be the one to use. sleep. Nasal CPAP eliminates the obstructive apnea
and the snoring that accompanies this condition when
Statement II: manometer calibrated in cm H2O the appropriate CPAP pressure is reached. Neither
from 0 to 3,000 cm H2O IPPB therapy, insertion of an oropharyngeal airway,
nor bronchodilator therapy is indicated or is helpful in
1,034 cm H2O
= 70.34 cm H2O/psig  50 psig the treatment of obstructive sleep apnea.
14.7 psig
Mask CPAP is also beneficial in the treatment of pa-
= 3,517 cm H2O
tients who have acute hypoxemic respiratory failure,
A manometer calibrated in cm H2O would have to ex- preventing endotracheal intubation. This mode of ther-
ceed 3,517 cm H2O. apy is also seen in the treatment and prevention of
postoperative atelectasis.
3,000 cm H2O = 42.6 psig
(1:561), (5:358–360), (13:637), (15:393, 733),
Statement III: manometer calibrated in mm Hg (16:565, 1115).
from 0 to 2,000 mm Hg
760 mm Hg IIA1b
= 51.7 mm Hg/psig  50 psig
14.7 psig 39. D. HMEs are most appropriately used for short-term
= 2, 585 mm Hg mechanical ventilation or support because of their lim-
itations in regard to added dead space volume resis-
A manometer calibrated in mm Hg would have to ex- tance to gas flow, decreased efficiency with high tidal
ceed 2,585 mm Hg. volumes and flows, and the possibility of humidity
2,000 mm Hg = 38.7 psig deficits over time. Also, spontaneously breathing
adults might display ventilatory patterns that decrease
Statement IV: manometer calibrated in in. Hg from HME efficiency. Caution must also be exercised in the
0 to 50 in Hg event secretions thicken or become more copious.
Such situations can cause airway obstruction. The
29.921 in. Hg HME can attach directly to the artificial airway, but
= 2.04 in. Hg/psig  50 psig
14.7 psig usually it is interfaced with the airway with the addi-
= 102 in. Hg tion of an angled patient connector.
A manometer calibrated in inches Hg would have to (1:665–667), (5:117–118), (13:127–129),
exceed 102 inches Hg. (15:798–799), (16:429–432).
50 in. Hg = 24.5 psig
IIA1a(2)
(1:93), (17:241–245). 40. C. A tracheostomy collar or a T-piece (Briggs adaptor)
can provide the needed oxygen, as well as humidifica-
IIA1l tion and heat. For these devices, only the air-entrainment
37. A. Available evidence does not support any increased port on the nebulizer can be varied to adjust the oxygen-
therapeutic effectiveness of mechanical percussors in delivery setting. The tracheostomy collar rests loosely
the administration of chest physiotherapy. Mechanical over the opening of the tracheostomy tube at the stoma
percussors help to ensure that patients receive consis- site. Therefore, the actual delivered FIO2 is virtually un-
tent therapy, however, and their use reduces practi- predictable, because depending on the patient’s inspira-
tioner fatigue. Percussion frequency can be controlled tory flow rate and respiratory frequency, various
by mechanical percussors, but the lack of tactile appli- amounts of room air can be entrained.
cations of percussions can result in trauma to a pa- If a tracheostomy patient requires a high and/or precise
tient’s soft tissues or chest wall. FIO2, a T-piece (Briggs adaptor) is the appliance of
(1:802–803). choice. A T-piece fits snugly on the 15 mm adaptor of

Chapter 4: Equipment 243

 the tracheostomy tube. The only room air that can en- IIA1h(2)
ter the system at the point of the patient’s airway is the 42. A. An oxygen concentrator provides convenient and
distal end of the T-piece. As long as the patient’s in- virtually maintenance-free oxygen for a patient who is
spiratory flow rate does not exceed that of the output receiving oxygen at home. Oxygen concentrators sep-
of the nebulizer, the set FIO2 should be achieved. If the arate the nitrogen and oxygen from room air by using
patient’s inspiratory flow rate exceeds the output of the a molecular sieve and an air compressor. All the pa-
nebulizer, the patient’s FIO2 will be less than that set at tient needs to do is clean the filters once a week. The
the room-air entrainment port of the nebulizer. home-care company should provide periodic service
(1:755–756), (7:422–424), (16:391–394). (every one or two months) to check the oxygen con-
centration delivered by the device and to check the
IIA1k alarms and connections.
41. B. Having the ability to identify the presence of at- A compressed gas cylinder system is labor intensive
electasis in a patient is essential for the CRT. The pa- for most home-care patients, as well as being ex-
tient’s chart often holds the first clue, because certain tremely costly. A liquid oxygen (LOX) system affords
clinical situations are more likely to cause atelectasis the patient a great deal of mobility. A smaller, portable
than others. For example, patients who are undergoing liquid oxygen tank is filled by the larger LOX system.
upper-abdominal or thoracic surgery should be con- Many patients experience difficulty filling the portable
sidered possible risks for atelectasis. Furthermore, if unit each week. Transfilling is a noisy, tedious process.
such patients have pre-existing lung disease (COPD) If the portable unit is overfilled, connections are prone
and/or smoke cigarettes, their risk for the development to freezing. An LOX system is also an expensive form
of atelectasis increases. of home-care oxygen delivery.
Clinical signs of atelectasis vary according to the de- A down side to an oxygen concentrator is the heat gen-
gree to which atelectasis is present. If a patient has erated by the device during operation. This heat might
minimal atelectasis, the patient might not display any contribute to a higher utility bill in the summer. This
signs. As the extent of atelectasis increases, the patient system remains the most cost-effective home oxygen-
might exhibit fine, late inspiratory crackles over the in- delivery system, however.
volved area of the lung. Bronchial breath sounds will
(5:17–23), (13:43–44), (16:894–897).
develop as the degree of alveolar collapse increases as
the airways leading to them remain patent. If alveoli
collapse and the airways leading to them become ob-
IIA1f(4)
structed, breath sounds are either absent or diminished. 43. A. The following equipment is necessary to perform
orotracheal intubation on a neonate:
The percussion note will be dull over the affected re-
gion of the lung, and the tactile fremitus will be de- • Miller (straight) laryngoscope blade and handle
creased. Mediastinal shift will occur if the atelectasis • suction equipment
is unilateral. The shift will be in the direction of the af- • manual resuscitation bag
fected side, because the intrapelural pressure is greater • mask
on the affected side as a result of the atelectasis. • oxygen
• stethoscope
From a physiological standpoint, if the atelectasis is • tape
significant enough, it can produce hypoxemia—which • Benzoin
in turn leads to tachycardia and increased WOB. At- • lubricating jelly (KY Jelly)
electasis also causes pulmonary (lung) compliance to • endotracheal tubes
decrease. The hypoxemia is caused by ventilation- • pulse oximeter
perfusion inequalities. The hypoxemia caused by at- • CO2 detector
electasis is not amenable to oxygen therapy, because it
results from increased shunting (Q̇ S/Q̇ T). A straight (Miller) laryngoscope blade is used with
neonatal intubation, because neonates have a large
Both IPPB and incentive spirometry (IS) are intended tongue and a high epiglottis. The tip of the straight
to prevent reverse atelectasis. IPPB is used when a pa- blade is used to directly displace the epiglottis. A Mac-
tient cannot follow instructions well enough to per- Intosh (curved) laryngoscope blade is not well suited
form IS. To perform IS, a patient must be oriented and for neonatal intubation because of these anatomic con-
coherent; otherwise, the therapy cannot be performed. siderations. The curved blade, which is used with
The patient in this question is alert and is capable of larger children and adults, is inserted into the vallecula
performing IS. (base of the tongue). As the laryngoscope is moved up-
(1:773–775), (7:234–235), (16:527–530). ward and forward, the glottis becomes exposed.

244 Chapter 4: Equipment

 Magill forceps are also unnecessary for intubation of gle. During endotracheal suctioning, the suction
newborns, because the endotracheal tube can be easily catheter is likely to enter the right mainstem bronchus
advanced over the short distance of the neonate’s upper more easily than the left, because of the angles at
airway. The endotracheal tubes are usually cuffless. which these primary bronchi branch. The Coudé
catheter is an angled catheter that might facilitate en-
(1:594–601, 1014), (16:589), (18:407–411).
trance into the left mainstem bronchus. In addition, the
type of tracheal tube used and the position of the pa-
IIA1d tient’s head might also facilitate left mainstem
44. B. What appears to be happening here is an inability of bronchus insertion. The whistle-tip and ring-tip
the CRT to create an adequate seal between the resus- catheters are straight catheters and are more likely to
citation mask and the patient’s face. This situation can enter the right mainstem bronchus. The Yankauer de-
result from improper hand placement on the part of the vice is a rigid suction tip used to remove oropharyn-
CRT, the mask being too small for the patient’s face, or geal secretions.
the mask being defective (containing a leak).
(1:616, 618), (13:182), (16:604).
In this situation, squeezing the bag more forcefully
would not correct for air escaping around the mask,
IIA1i(1)
nor would it increase the number of compressions per
minute. The flow rate set on the flow meter is ade- 48. D. The breathing circuit provides the connection be-
quate. Most self-inflating manual resuscitators operate tween a ventilator and the patient’s lungs. Flexible,
at an oxygen liter flow of 8 to 12 liters/min. large-bore tubing that is resistant to leaking or kinking
is required for inspiratory gas delivery and expiratory
(5:254–259), (13:148–153). gas removal. A wye piece is used to connect the cir-
cuit’s inspiratory limb, expiratory limb, and patient
IIA1h(5) adaptor. An exhalation valve (manifold), which is
45. B. The single-breath carbon monoxide lung-diffusing needed in the circuit to control the main flow of gas, is
capacity (DLCO) study uses a gas mixture containing connected to a ventilator by small-bore tubing.
0.3% CO, 10% He, 21% O2, and approximately 69% (1:842), (5:354–355).
N2. The two gases that are analyzed during the study
are carbon monoxide and helium. The CO analyzer is
used for determining the final fractional alveolar CO IIA1a(3)
value (FACOfinal), and the helium analyzer is essential 49. D. Because the patient is alert and cooperative but se-
for measuring the fraction of exhaled helium concen- verely hypoxemic (PaO2 of 40 torr on an FIO2 of 0.60),
tration value (FEHe). Neither the oxygen nor the nitro- refractory hypoxemia must be present. Therefore, a
gen require analysis during the single-breath DLCO. higher FIO2 might have little or no effect other than in-
creasing the chance of oxygen toxicity. In such cir-
(6:113), (11:176–177), (16:240–241).
cumstances, mask CPAP is selected to provide the
most appropriate treatment without having to intubate,
IIA1a(2) mechanically ventilate, and add PEEP. The patient
46. B. A T-piece or Briggs adaptor is designed to be used would have to be monitored closely for signs of intol-
with an artificial airway (ET tube or tracheostomy erance, however.
tube) to provide aerosol (humidity) with a precise
FIO2, while the others have one or more limitations The CPAP increases the patient’s functional residual
that preclude their use. The T-piece, therefore, is se- capacity and improves gas distribution to poorly ven-
lected to help prevent a humidity deficit from develop- tilated regions. Therefore, CPAP is generally effective
ing—while at the same time, delivering the required in correcting V̇A/Q̇ C abnormalities characterized by
FIO2 to the patient. A piece of aerosol tubing (approx- perfusion in excess of ventilation (shunt effect or ve-
imately six inches long) should be added to the outlet nous admixture). When these lung regions experience
(distal end) of the T-piece as a reservoir, and the flow more ventilation, the hypoxemia can be alleviated or
rate should be adjusted to assure a consistent FIO2. lessened, depending on the extent to which this prob-
lem is contributing to intrapulmonary shunting (capil-
(1:755–756), (13:77–79). lary shunting plus a shunt effect).

IIA1g (1:561), (5:363), (13:673), (15:733), (16:565, 1115).

47. B. The trachea bifurcates into the right and left main-
stem bronchi. The right mainstem bronchus branches IIA1a(2)
off at an angle of 20 to 30 degrees, whereas the left 50. B. An oxyhood can deliver a range of FIO2s from just
mainstem bronchus comes off a 40- to 60-degree an- more than 0.21 to 1.0. Because of adequate flow rates

Chapter 4: Equipment 245

 with precise FIO2s and because the oxyhood can be 7. lubrication jelly (KY Jelly)
well sealed, the FIO2s are rather fixed. The oxyhood is 8. suction equipment
ideal for infants who maintain a neutral, thermal envi-
(1:594, 599–601), (16:592–594).
ronment; however, the gas flow into the oxyhood must
be directed away from the infant’s face to avoid heat
loss, cold stress, increased oxygen consumption, and IIA2
possibly apnea. 53. D. Processing indicators are used to demonstrate
whether a sterilization or disinfection process has oc-
Oxygen tents are essentially used for children who curred. Two types of indicators are used: chemical and
have croup and cystic fibrosis. Placing infants in these biological.
enclosures creates difficulties with overall treatment.
The enclosure has to frequently be invaded, disturbing Chemical indicators (at best) signal that equipment has
the oxygen-enriched environment. been exposed to a sterilizing agent. They cannot reveal
whether sterilization or disinfection has actually oc-
(1:746, 759–760), (7:424–425), (16:394–395). curred. For example, when preparing and packaging
equipment for autoclaving, a chemical indicator tape is
IIA1n placed on the outside of the package. All this type indi-
51. A. Flow-sensing spirometers, or pneumotachometers, cator does is confirm that the package was exposed to
are lightweight and portable volume and flow-measuring certain conditions for a specified temperature and time.
devices. They measure flow rates directly and provide
Only biologic indicators can verify the attainment of
volume measurements by electronic integration (based
sterilization. Biologic indicators contain bacterial
on time) of the flow-rate data. Furthermore, flow-sensing
spores. These bacterial spores are located inside a
spirometers have an excellent frequency response,
glass capsule on an outer plastic vial. The glass cap-
making them more accurate than volume displacement
sule, which is crushable, contains a growth medium
devices (especially for tests such as the maximum vol-
(tryptic soy broth). The top or cap of the biologic indi-
untary ventilation test, or MVV).
cator vial has a gas-permeable bacterial filter.
Volume-displacement spirometers (water sealed, dry,
The biologic indicator is wrapped with the packaged
rolling-sealed, and bellows or wedge) are much larger
equipment and is placed in a somewhat inaccessible
than their flow-sensing counterparts. They are often
area within the sterilizer. Following the sterilization
cumbersome, especially when interfaced with com-
cycle, the glass ampule is crushed, and the bacterial
puter hardware; consequently, their portability is lim-
spores fall into the growth medium. The biologic indi-
ited.
cator is incubated according to the manufacturer’s
(1:373), (5:272–280), (6:245–258), (11:3–17). specifications. When the incubation period ends, the
absence of turbidity or the absence of a color change
IIA1f(4) demonstrates that sterilization has occurred. The
52. B. When intubating an awake adult patient, the CRT spores have been killed by the sterilization process.
must anesthetize the patient’s pharyngeal and laryn- (1:58–59).
geal reflexes. Usually, 2% lidocaine spray is used for
both orotracheal and nasotracheal intubation per- IIA1m(1)
formed on a conscious patient. For nasotracheal intu-
54. D. A pressure (aneroid) manometer is used to obtain an
bation, a 0.25% phenylephrine spray is used on the
MIP measurement. A pressure, or aneroid, manometer
mucous membranes of the nasal cavity to induce local
indicates pressure changes that are directly proportional
vasoconstriction to reduce the risk of nasal bleeding.
to the expansion and contraction of a hollow diaphragm
Magill forceps are used to guide the nasotracheal tube
housed inside the pressure manometer. A pointer is
through the oropharynx and into the trachea.
linked to the diaphragm via a set of small gears. These
Other equipment used during nasotracheal intubation gears help transform the linear motion of the diaphragm
is listed as follows: to rotary motion, which is displayed by the pointer on the
calibrated face of the aneroid manometer.
1. oxygen equipment
2. manual resuscitator and mask An aneroid manometer is also used to obtain an MEP
3. Yankauer suction tip measurement, an endotracheal tube cuff pressure read-
4. curved (MacIntosh) or straight (Miller) laryngo- ing, and pressures developed during positive pressure
scope blades mechanical ventilation.
5. tape
(10:179–180), (11:64–67).
6. 3- to 5-cc syringe

246 Chapter 4: Equipment

IIA1a(1) IIA1a(2)
55. B. A transtracheal oxygen (TTO) delivery device in- 58. C. The oxyhood provides an enclosure for the infant’s
stills oxygen directly into a person’s trachea via a head, to which a heated and humidified gas flow at a
percutaneous catheter. TTO delivery devices are rec- predetermined FIO2 can be delivered. The other de-
ommended for patients who are aware of the cosmetic vices, i.e., incubator, mist tent, and croupette, are un-
appearance of the oxygen-delivery device, who expe- able to provide a consistent FIO2 because of their
rience nasal irritation from a nasal cannula, and who limited operational characteristics and their inability to
are are cost conscious about their oxygen usage. provide heated humidification. An oxyhood can also
be used inside either an incubator or an isolette to bet-
The flow rate of oxygen to the TTO devices is gener-
ter control the thermal environment.
ally reduced by 40% to 50% of that used with nasal
cannulas. (1:760), (5:75–77), (13:79–80), (16:394–395).
(1:745), (7:408–409), (16:384–385).
IIA1b
IIA1l 59. B. For patients who have artificial airways, the
primary goal is to provide gases near 100% body
56. C. Chest physiotherapy can be delivered by using any
humidity. Heated aerosol (heated humidification)
of the three types of percussors available—manual,
would best accomplish this goal. The particulate wa-
electrically powered, or pneumatically powered. Each
ter tends to keep secretions liquified, reducing the
variety has a neonatal (infant) adaptor or model. If an
risk of airway obstruction. Some clinicians, how-
adult’s hand cannot be used effectively to apply chest
ever, would argue that heated aerosols increase the
physiotherapy, a mechanical percussor with the appro-
risk of infection and bronchospasm when compared
priate adaptor for the patient’s size must be used.
with heated humidity from a cascade humidifier or
Neonates and infants are too young to understand how
other heated humidifier supplying high-output mole-
to use a flutter valve.
cular water.
(18:377–379).
(1:667–672), (13:117–119), (15:794–795).
IIA1k
IIA1d
57. B. According to the AARC Clinical Practice Guide-
60. D. The mouth-to-valve mask is a transparent mask
lines for Incentive Spirometry, incentive spirometry is
with a mouthpiece, to which is attached a one-way
indicated for the presence of conditions predisposing
valve. The clear mask permits the practitioner to see
to the development of pulmonary atelectasis (upper-
vomitus if it occurs. The one-way valve provides di-
abdominal surgery, thoracic surgery, and surgery on
version of the victim’s exhaled gas away from the res-
patients who have COPD), the presence of pulmonary
cuer. The presence of an oxygen inlet enables the
atelectasis, and the presence of a restrictive defect as-
administration of supplemental oxygen during CPR at
sociated with quadriplegia or a dysfunctional di-
5 to 30 liters/minute.
aphragm. A cholecystectomy is an upper-abdominal
surgical procedure. (American Heart Association: Healthcare Provider’s
Manual, p. 73).
For IS to be effective, patient education is paramount.
Patient education regarding the procedure needs to oc-
cur in the preoperative period, while the patient is with- IIA1i(2)
out pain and is coherent. The expectation is that the 61. D. A PEEP device that is a true threshold resistor does
patient will be alert and cooperative post-operatively. If not restrict flow; consequently, it produces a lower
the patient is not alert, is uncooperative, or has some mean airway pressure. A PEEP device that restricts
other condition limiting his involvement, IPPB should flow by channeling the exhaled gas through a small en-
be initiated. trance and/or exit port will act as a flow resistor, creat-
ing expiratory resistance or expiratory retard. A
For the patient in this question, the expectation is that spring-loaded diaphragm or disk might create expira-
he will be capable of listening, following instructions, tory resistance, depending on the elasticity of the
and performing the IS technique. The goal of IS in this spring as well as the orifice of the disk seat. In addi-
case is the prevention or reversal of atelectasis related tion, a pressured balloon valve might also create expi-
to upper-abdominal surgery. ratory resistance if emptying of the balloon is impeded
(AARC Clinical Practice Guidelines for Incentive or if the area under the valve is small.
Spirometry, Respiratory Care, 41:629–636, 1996), (5:355–357), (13:353–354).
(1:774–776), (7:234–237), (16:528–532).

Chapter 4: Equipment 247

IIA1h(4) spirometers often have multiple chambers with some
62. A. The plunger of a vented arterial sampler should be type of indicator (balls or floats) that rise to various
preset to the desired volume of blood. A vented arter- levels within the chamber, based on the inspiratory
ial sampler is designed to have a temporary air-blood flow rate that the patient generates. Chest percussors
interface. As the arterial blood rises in the sampler, the and flutter valves are used to improve bronchial hy-
air escapes through the vent. When the blood reaches giene and to prevent or reverse atelectasis. Neither pro-
the vent, the vent seals. The sampler is full; it will not motes deep breathing, however.
accept any additional blood volume. The sampler (5:186–189), (13:247–251).
should be immersed in ice water after the arterial
blood is in the sampler. The crystalline anticoagulant IIA1h(2)
will dissolve in the plasma. Reconstitution with nor-
66. D. A liquid oxygen (LOX) system affords a home-care
mal saline would dilute the anticoagulant and would
oxygen patient the opportunity to move about and
close the vent on the sampler.
travel more freely. Portable, compressed oxygen cylin-
(Gauer, P., Friedman, J., and Inery, P., “Effects of sy- ders are functional but bulky, cumbersome, and non-
ringe and filling volume on analysis of blood pH, oxy- aesthetic. The fact that one liter of liquid produces 860
gen tension, and carbon dioxide tension,” Respiratory liters of gaseous oxygen makes the LOX system suit-
Care, 1980; 25:558–563). able for portability. Home LOX systems generally
range in capacity between 20 and 43 liquid liters,
IIA1c which is approximately equivalent to 16,400 and
63. A. An ultrasonic nebulizer converts electrical energy to 35,200 liters of oxygen gas.
mechanical energy via the piezoelectric transducer and A smaller, portable reservoir is used by the patient
uses a motor blower to deliver air, rather than oxygen, when he leaves the home. These units have a capacity
with up to 6 ml/minute of aerosol output. Particle size ranging from 0.6 liter to 1.23 liters, translating to an
is determined by the frequency (1.35 MHz), while out- estimated gaseous capacity of 500 to 1,058 liters. The
put is determined by the amplitude. An oxygen blender portable units are also relatively lightweight, ranging
or other device can be incorporated into the delivery from about 5.3 to 9.0 pounds. The LOX system is the
system to provide an appropriate FIO2. most expensive source for home oxygen delivery.
(1:675–676), (5:154–161), (13:121–122), (5:22–28), (13:41–43).
(15:803–804), (16:462–465).
IIA1a(1) IIA1b
64. D. A simple mask is generally used on trauma victims
67. A. An HME is comprised of material that enables con-
and on patients who require short-term oxygen at a
densate and heat to accumulate within the device dur-
moderate FIO2 (e.g., patients in the recovery room).
ing exhalation. During the ensuing inspiration, the air
This mask operates at flow rates of 5 to 12 liters/min.
passes through the HME and reclaims heat and mois-
A minimum of 5 liters/min. is required to prevent the
ture. The inspired air now contains heat and moisture
patient from rebreathing CO2. The 5 liters/min. oxygen
for delivery to the patient’s respiratory tract. No mois-
flow rate flushes the exhaled CO2 from the mask dur-
ture accumulates in the ventilator circuit when an
ing exhalation. The approximate FIO2 range provided
HME is used.
by a simple mask is 0.3 to 0.5 liters/min.
On the other hand, a heated cascade, a heated wick hu-
(1:745, 749–750), (7:410–414), (16:386–387).
midifier, and a heated pass-over humidifier would all
contribute to the presence and accumulation of con-
IIA1k densate (water) in the ventilator circuit. The degree to
65. D. Incentive spirometers are devices intended to en- which each of these humidifiers contributes to the
courage patients to breathe deeply, especially post- amount of water building up in the circuit can be re-
operative patients. The purpose of breathing deeply is duced by the incorporation of a heated wire circuit.
to prevent post-operative atelectasis. Two types of The heated wire circuit would elevate the temperature
incentive spirometers are commonly used: volume- of the ventilator tubing along its entire length, thereby
oriented spirometers and flow-oriented spirometers. reducing the amount of water that condenses as the hu-
Volume-oriented devices encourage the patient to midified gas flows from the humidifier to the airway
breathe deeply in order to achieve a target volume. opening.
Several volume-oriented incentive spirometers are
commercially available. Flow-oriented incentive (1:664–667, 671–673), (5:96–97, 107–116),
(13:94–100).

248 Chapter 4: Equipment

IIA1n Table 4-7
68. D. Two types of instruments are used to measure Degree of Hypoxemia PaO2 RANGE
volumes and flow rates: flow-sensing spirometers
and volume-displacement spirometers. Flow-sensing mild 60–79 torr
spirometers directly measure airflow rates. The flow- moderate 40–59 torr
rate measurements are electronically integrated into severe less than 40 torr
volume measurements. Types of flow sensing spirom-
eters, also called pneumotachometers, include (1)
A stable COPD patient who has hypoxemia and nor-
pressure-differential, (2) heated wire, (3) Pitot tube,
mocapnia is not in respiratory distress. As long as the
(4) ultrasonic, and (5) rotating vane (turbine). These
patient is breathing at a normal ventilatory rate and
flow-sensing spirometers employ different principles
pattern and has a relatively normal tidal volume, a
of operation and incorporate few to no moving parts.
nasal cannula at 1 to 2 liters/min. should be sufficient.
Thus, they respond quickly to rapid changes in a pa-
Under these breathing conditions, a nasal cannula will
tient’s airflow patterns during inspiration and exhala-
deliver a relatively stable FIO2.
tion. Flow-sensing spirometers have a better frequency
response than volume-displacement devices. There- A nasal cannula is described as a low-flow or variable-
fore, they are more accurate at measuring flow rates. performance oxygen-delivery device. Table 4-8 lists
the oxygen liter flow rate and its corresponding antic-
Types of volume-displacement spirometers include (1)
ipated FIO2 when a patient has a minute ventilation of
water-sealed, (2) bellows (wedge), and (3) dry rolling-
8–10 liters/min., a ventilatory rate of fewer than 20
sealed. Volume-displacement spirometers are fine for
breaths/min., a tidal volume of less than 800 cc, and an
measuring exhaled volume. Measurements of volumes
inspiratory flow rate of 10 to 30 liters/min.
and flow rates are often obtained from the kymograph
tracings used with the water-sealed spirometers. Flow (1:743–744, 745), (7:405–407), (16:381–383).
rates from the dry, rolling-sealed spirometers are pro-
portional to the velocity of the piston. Flow rates from Table 4-8
the bellows (wedge) spirometer are determined from
Nasal Cannula
chart paper that moves at a fixed speed under a pen.
Oxygen Flow Rate Approximate FIO2
Volume-displacement devices encounter the inertia re-
sulting from numerous moveable internal components; 1 liter/min. 0.24
therefore, they have a limited frequency response. 2 liters/min. 0.28
3 liters/min. 0.32
(1:373), (5:272–280), (6:245–258), (11:3–17). 4 liters/min. 0.36
5 liters/min. 0.40
IIA2 6 liters/min. 0.44
69. D. Ethylene-oxide sterilization would not be a suitable
method to use in this situation because of the lengthy
aeration time. The tubing would not be ready by the IIA1i(2)
time it was needed. Steam autoclaving would not be
71. C. A Rudolph valve is a one-way valve mechanism
useful under these conditions either, because the high
that can serve as pop-off for high pressure but is not
temperature (121ºC to 121ºC) can damage the ventilator
used for application of PEEP by itself.
circuit. Pasteurization kills Mycobacterium tuberculosis
microorganisms at a temperatures of about 70ºC in 30 (5:355–357), (13:353–354).
minutes. Glutaraldehyde can kill M. tuberculosis mi-
croorganisms in 20 minutes at room temperature. IIA1h(3)
Other suitable methods for processing the ventilator 72. D. A small compressed gas cylinder (“E” size) is gen-
tubing in this situation include a stabilized hydrogen erally the most practical oxygen-supply system to use
peroxide-based solution and a 1:50 dilution of sodium for a patient transport. The manifold (two or more
hypochlorite. Both are tuberculocidal in about 10 minutes. large cylinders attached together) and liquid reservoir
(1:43–47), (9:708–712), (13:494–498), (16:1066). systems are large supply systems generally used for
supplying oxygen to hospital piping systems. A con-
IIA1a(1) centrator is bulky, requires an electrical supply, and
has flow-rate limitations. The compressor delivers
70. C. Hypoxemia is graded as mild, moderate, or severe pressurized air and not oxygen.
based on the patient’s PaO2 value. Table 4-7 lists the de-
gree of hypoxemia and its corresponding PaO2 range. (1:719), (5:31), (13:42–43), (16:351–352).

Chapter 4: Equipment 249

IIA1g Once CO exposure has been confirmed and the degree
73. B. The ring tip and multiple side ports of the straight of carboxyhemoglobin has been measured, the best ap-
ring-tip suction catheter provide the best protection proach to oxygen therapy can then be determined. A
against mucosal trauma from physical or suction damage nonrebreathing mask operating within a range of 6 to
(Figure 4-10). The ring tip of the catheter helps prevent 10 liters/min. can deliver an FIO2 ranging from 0.5 to
suction attachment to the mucosal wall, while the side greater than 0.9.
ports relieve vacuum if the tip becomes occluded. Whis- (1:746, 750), (7:414–417), (16:387–389).
tle-tip suction catheters have the tip cut at an angle and
usually have one or more side ports to minimize mucosal IIA1h(4)
trauma, but they might cause more damage than the
77. D. According to the AARC Clinical Practice Guide-
straight ring tip with multiple side ports.
lines for Capnography/Capnometry During Mechani-
cal Ventilation, capnography can be used to determine
Angled end
Open end ring tip that endotracheal intubation, as opposed to esophageal
intubation, has occurred. When endotracheal intuba-
tion has been successful, the CO2 level on the capno-
graph rises to about 4.5% to 5.5%. On the other hand,
Staggered Opposing if the endotracheal tube is inserted in the esophagus,
side openings side openings the capnogram plateaus to zero in a few breaths.
(AARC Clinical Practice Guidelines for Capnogra-
phy/Capnometry During Mechanical Ventilation, Res-
piratory Care, 40:1321–1324, 1995), (1:363–367,
Whistle Tip Ring Tip 598), (5:315–316), (10:101), (13:198), (16:314).
Suction Suction
Catheter Catheter
IIA1h(1)
Figure 4-10
78. D. Because the patient is being transported, using a
(13:182), (16:605).
Bourdon gauge flow meter is more appropriate than a
compensated Thorpe flow meter. In the event that the
IIA1f(4) E cylinder needs to be placed in any position other
74. D. Blades are generally classified as either straight than a vertical position, the flow meter will indicate
(Miller, Wis-Hipple, Jackson-Wisconsin, and Flag) or the correct flow rate. A Thorpe flow meter float or ball
curved (MacIntosh). Care must be taken by the opera- will be affected by the position; hence, the flow-rate
tor during intubation to ensure that pressure is not reading will be inaccurate.
placed on the upper teeth, using them as a lever. The
design of the curved blade can minimize this hazard if Furthermore, a pin index safety system (PISS) must be
used appropriately. A left-handed CRT must learn to the connection, because an E cylinder will not accept a
intubate in the same manner as a right-handed person. diameter index safety system (DISS) connection. The
PISS connection uses the yoke adaptor, which contains
(1:595–597, 601). pins that match holes on the face of the valve stem—
while the DISS connection fastens with an internally
IIA1e(1) threaded hex nut.
75. B. Powering mechanism refers to the energy source (1:725–727, 731–733), (5:43–49), (13:50–54),
that provides power to make the ventilator operational. (16:353–360).
(1:857), (13:360).
IIA1f(3)
IIA1a(1) 79. B. Tracheal buttons can be used to maintain a tracheal
76. B. This patient has likely been in a fire or a smoke- stoma while a patient is being weaned from a tra-
filled environment. The concern with this patient is she cheostomy tube. A tracheal button provides access for
might have incurred carbon monoxide (CO) poison- secretion removal as well as for emergency mechani-
ing. Until an arterial blood sample is analyzed via a co- cal ventilation. This device extends from the external
oximeter, the presence and extent of CO poisoning stomal opening to just inside the anterior tracheal wall.
cannot be ascertained. Therefore, providing the patient The absence of an intratracheal cannula appreciably
with the oxygen-delivery device that renders the high- reduces the airway resistance through the lumen. A
est FIO2 is appropriate for the time until the presence one-way valve can be attached to the external portion
and degree of CO exposure is determined. of the tracheal button. This device enables air to enter

250 Chapter 4: Equipment

 at the stoma but forces it to exit through the upper air- ment of room air, therefore helping to maintain a high,
way, enabling the patient to speak. stable inspired oxygen concentration. A canopy device
or tent is not indicated when a simpler and more effec-
A Lanz tracheostomy tube is a conventional tra-
tive system is available. An air entrainment mask is not
cheostomy tube with an external pressure-regulating
an option for a patient who has had a tracheostomy.
valve and control balloon to regulate intracuff pres-
sure. A Kamen-Wilkinson Fome-Cuff tracheostomy (1:755–757), (13:77–79).
tube has a self-inflating cuff. When the pilot balloon is
open to the atmosphere, the foam cuff self-inflates. Air IIA1m(1)
is not injected from a syringe into the cuff-inflating 82. D. This adult male patient is intubated with a tube that
line. A speaking tracheostomy tube is a also conven- is best suited for a 16-year-old patient or for a small fe-
tional tracheostomy tube with a separate pilot tube that male. A more appropriate tube size would be an 8.5 to
directs a flow of gas (compressed air or O2) to an open- 9.5 mm I.D. To maintain a seal, the cuff of a 7.0 mm
ing above the inflated cuff. This gas flow moves past I.D. endotracheal tube (even with a compliant cuff)
the larynx and out the upper airway, permitting the pa- placed in an 80-kg adult male would will require over-
tient to speak. A seal against the trachea is maintained, inflation, causing the cuff to act as a low-compliant
enabling gas to enter the lungs for ventilation. cuff. To compound the problem, a low-compliant
(1:610–616), (16:577, 582–583). (high-pressure/low-volume) cuff was used. These two
situations in combination will easily cause cuff pres-
IIA1g sures to exceed the maximum capability of the cuff
manometer. The CRT should recognize that this pa-
80. C. The Yankauer tonsil tip is a suction device having a
tient’s cuff pressure will be excessively high. Damage to
large internal lumen designed for removing food parti-
the manometer is also possible. The operating instruc-
cles, vomitus, viscous secretions, or other substances
tion for the Posey Cufflator (0 to 120 cm H2O) indicates
from the oropharynx. Normal suction catheters would
that it should only be used with tracheal tubes that have
be ineffective for removing large particulate or thick
high-volume, low-pressure cuffs. Reintubation with a
substances, because these catheters would become oc-
larger endotracheal tube having a high-volume, low-
cluded. The Coudé is designed to facilitate suctioning
pressure cuff would be the best recommendation.
of the left mainstem bronchus.
(The Posey Cufflator: Tracheal Cuff Inflator and
(1:616), (13:182), (16:604).
Manometer, product information, J. T. Posey Co.),
(1:609–610), (5:240–241).
IIA1a(2)
81. B. A T-piece, also known as a Briggs adaptor, is the IIA1i(2)
best choice when the FIO2 needed is 0.60. A tra-
83. C. An ideal CPAP system should maintain a near-
cheostomy mask is best used to provide low oxygen
constant baseline pressure with minimum pressure
concentrations and/or humidity. A high-flow system is
fluctuations. A near-constant baseline pressure is ac-
appropriate in this situation.
complished with a high flow rate, i.e., 60 to 90 liters/
The air:oxygen ratio for 60% is 1:1 (Table 4-9). minute. In addition, the use of a reservoir bag will en-
able periodic inspiratory flow rates to exceed the sys-
Table 4-9: Relationship among source flow, entrained flow,
and total flow
tem flow without the loss of system pressure. Flow
rates of 20 to 30 liters/minute are acceptable as long as
Flow Meter Setting Air/O2 Ratio Total Flow the system is closed, and a large reservoir system (12
(liters/minute) (liters/minute) (liters/minute) to 18 liters/minute) is available to maintain a near-
constant baseline pressure. The CPAP device should
10 liters/minute = 1:1 not impede flow during exhalation; therefore, it must
10 10 + 10 = 20
10 liters/minute
behave as a true threshold resistor (providing no expi-
11 liters/minute = 1:1
11 11 + 11 = 22 ratory resistance). Humidification should be provided
11 liters/minute
12 liters/minute = 1:1 by a device offering low flow resistance and capable of
12 12 + 12 = 24 maintaining a closed system.
12 liters/minute
13 liters/minute = 1:1 (1:865), (5:363–366), (13:637–639).
13 13 + 13 = 26
13 liters/minute

IIA1h(2)
A normal peak inspiratory flow rate is about 25 to 30 84. D. Three types of medical gas compressors are available:
liters/minute. An extension or reservoir tubing is placed piston, diaphragm, and centrifugal or rotary. The piston
on the distal end of the T-piece to help prevent entrain- air compressor employs a piston driven by an electric

Chapter 4: Equipment 251

 motor. The compressed air is stored in a reservoir to meet significantly. Therefore, the methods of analysis suit-
high flow demands. The pressure is reduced to 50 psig able for monitoring the degree of hyperoxia in a
before being used. This compressor can be used to neonate would include transcutaneous PO2 monitoring
supply the demands of a hospital system. The di- and arterial blood-gas analysis. Both of these tech-
aphragm compressor has no reservoir and is not capa- niques provide the PO2 measurements.
ble of providing large amounts of compressed air;
A pulse oximeter and a co-oximeter would be of no
rather, it is mostly used to power small-volume nebu-
use, because they measure the oxyhemoglobin satura-
lizers. The centrifugal or rotary compressor is used in
tion. Monitoring for hyperoxia in neonates is critical,
some adult ventilators and is also capable of supplying
because if the PaO2 increases too much, Retinopathy of
the demands of a hospital system.
Prematurity (ROP) can develop. This condition can
(1:835–836), (5:13–17), (13:381), (16:647). lead to blindness in the neonate.
(1:354–355), (5:292), (10:102–103), (13:188–189).
IIA1a(2)
85. B. Mist tents, croupettes, and aerosol tents are envi- IIA1h(1)
ronmental devices that are capable of delivering cool 89. A. An adjustable reducing valve can control the output
mist (aerosol) through the use of ice or refrigeration pressure from 0 to 100 psig. Figure 4-11 illustrates the
units. These devices can also be used to supply sup- functional components of an adjustable reducing valve.
plemental oxygen (FIO2 might vary) with the cool
mist. They are particularly suited for young children
who have an upper-airway obstruction caused by
laryngotracheal swelling or edema (as seen with
croup). Care should be exercised in their assembly to
ensure proper operation and therapeutic application.
(1:677, 759–760), (5:78–79, 169–173).

IIA1d
86. A. The pressure relief (pop-off) valve on a self-
inflating resuscitation bag is factory-set between 30
and 35 cm H2O.
(13:198). Figure 4-11: Functional components of an adjustable re-
ducing valve.
IIA2 The handle at the tip of the diagram can adjust the ten-
87. B. Ethylene oxide gas sterilization effectively sion on the spring below it, which in turn changes the
processes mechanical ventilator tubing, as long as the pressure at the high-pressure inlet. When the pressure
aeration time for the material is sufficient. High-level inside the pressure chamber exceeds that in the ambient
disinfectants (glutaraldehyde, a stabilized hydrogen pressure chamber, the diaphragm rises—and the pop-up
peroxide-based solution, and sodium hypochlorite) are valve closes the nozzle. When gas leaves the pressure
useful for the processing of ventilator tubing. Pasteur- chamber through the outlet, the pressure in the pressure
ization is useful for this purpose, as well. Heat at be- chamber falls. The tension on the spring in the ambient
low 70ºC does not damage tubing material. Seventy pressure chamber exceeds the force of the diaphragm.
percent ethyl alcohol is classified as an intermediate- The diaphragm is pushed down, removing the seal cre-
level disinfectant, along with 90% isopropyl alcohol. ated by the pop-up valve against the nozzle. Gas from
Both agents can damage rubber and plastics. Low- the tank enters the pressure chamber. This sequence of
level disinfectants include quaternary ammonium events continues as long as gas flows from the cylinder.
compounds (quats) and acetic acid.
A preset reducing valve maintains a fixed preset ad-
(1:44–47), (7:708–714), (13:493–497), (16:1066). justment on the spring between the ambient and pres-
sure chambers. The tension on the spring is factory
IIA1h(4) preset to deliver 50 psig. A multiple-stage reducing
88. C. When assessing the degree of hyperoxia, the partial valve lowers the source pressure to between 200 to 700
pressure of dissolved oxygen in the arterial blood psig in the first stage and to 50 psig in the second
(PaO2) must be measured. Because of the shape of the stage. Multiple-stage reducing valves are not routinely
oxyhemoglobin dissociation curve, the arterial oxygen used in clinical practice.
saturation (SaO2) changes little as the PaO2 increases (1:728–729), (5:39–40), (13:49–50), (16:354–356).

252 Chapter 4: Equipment

IIA1a(2) deoxyhemoglobin (HHb) absorb the red and infrared
90. D. The order calls for a specific FIO2. This prescription light, respectively. The ratio of the amount of light ab-
is best carried out via a high-flow system. A nasal can- sorbance between these two types of hemoglobin is
nula, partial rebreathing mask, and simple mask are all converted to oxygen saturation.
low-flow oxygen-delivery systems. Although a nasal Some pulse oximeters display the plethysmographic
cannula at 1 liter/minute can deliver approximately waveform. The purpose of the plethysmographic
24%, this delivery is dependent on the patient’s venti- waveform along with the SpO2 readout is to give a vi-
latory pattern. A well-fitted partial rebreathing mask sual indication of the adequacy of perfusion.
will deliver oxygen concentrations between 35% to
60% at flow rates of 6 to 10 liters/minute. A simple The following factors adversely affect the SpO2 value:
mask will deliver oxygen concentrations between 35% • HbCO
to 55% at flow rates of 6 to 10 liters/minute. Flow rates • metHb
of less than 5 liters/minute should not be administered • anemia ([Hb] less than 12 g/dl)
via a simple mask, because low flow rates will not • vascular dyes
completely flush the patient’s exhaled volume from the • dark skin pigmentation
mask. Low flow rates to the mask will enable a build- • nail polish
up of carbon dioxide, because the mask will function as • ambient light
an extension of the patient’s anatomic dead space. • poor perfusion
(1:752–754), (5:49–53), (13:76–77), (15:879–885), • motion
(16:390–391). • MRI
(1:359–363), (5:298–300), (10:95–99), (13:191–195),
IIA2 (16:310–312).
91. A. Following each bronchoscopy procedure, the
fiberoptic bronchoscope must first be cleaned with IIA1d
soap and water to help remove surface material from 93. A. The Hope II has a spring-ball, patent valve that does
the device to enable the disinfectant to come in contact not open in response to spontaneous breathing. The
with all surfaces of the instrument. All endoscope AMBU E-2 has a diaphragm valve; Laerdal has a di-
channels must be included in this process. Glutarade- aphragm and duck-bill valve; and the PMR II has a di-
hyde (alkaline or acidic) is suitable for use on fiberop- aphragm and leaf valve. Resuscitators that enable the
tic bronchoscopes. patient to spontaneously breathe and receive 100%
As with all endoscopes, fiberoptic bronchoscopes must oxygen by opening the patient valve might be prefer-
be thoroughly rinsed through all channels. Sterile wa- able, because the patient can remain attached to the
ter is preferred; however, an alcohol rinse solution is manual resuscitator if spontaneous ventilation is pre-
acceptable. Following the rinsing process, the endo- sent. This arrangement will ensure the administration
scope must be thoroughly dried (channels included) of 100% oxygen.
with forced air. (1:649), (13:198).
Processes such as ethylene oxide, steam autoclaving,
pasteurization, and alcohol can cause damaging effects IIA1f(1)
to the bronchoscope. Acetic acid does not have the 94. C. An oropharyngeal airway is used to prevent or re-
range of effectiveness possessed by the aldehydes (i.e., lieve airway obstruction primarily caused by the
glutaraldehyde). tongue lying against the posterior pharyngeal wall.
This device helps provide a patent airway for ventila-
(1:51–52), (7:713).
tion before endotracheal intubation is performed and
can also serve as a bite block after endotracheal intu-
IIA1h(4) bation. An oropharyngeal airway is indicated only for
92. B. A pulse oximeter uses spectrophotometry and patients whose gag reflex is suppressed, however, be-
plethysmography to provide continuous, noninvasive cause this device might stimulate vomiting.
monitoring of the blood’s arterial oxygen saturation.
The oxygen saturation reading obtained from a pulse (1:647–648), (5:237–239), (13:158), (15:826),
oximeter is given as the SpO2. A light-emitting diode (16:656–567).
(LED) sends red and infrared wavelengths of light
through the patient’s finger. Some of the light is ab- IIA1f(2)
sorbed, and some light passes through the finger’s tis- 95. A. The intra-arterial pressure in the trachea is approx-
sues to a photodetector. Oxyhemoglobin (HbO2) and imately 30 mm Hg. Lateral tracheal pressure greater

Chapter 4: Equipment 253

 than 30 mm Hg, or about 40 cm H2O, will cause arter- flexibility because of variations among patients. Table
ial blood flow to cease. The ideal cuff pressure should 4-10 lists recommended endotracheal tube sizes for
be less than 20 to 25 mm Hg to maintain tracheal per- pediatric and adult patients.
fusion. To minimize pressures, endotracheal tubes that
Table 4-10: Recommended endotracheal tube sizes for pe-
have a high residual volume and a low pressure should diatric and adult patients
be used. These tubes have a broad tracheal wall contact
area, which will exert low pressures on the tracheal mu- Tube Size Suction Catheter
cosa. Increases in the cuff volume of these tubes will Age (mm I.D.) (French)
cause only small increases in the intracuff pressure.
Newborns 3.0 6
(1:609), (5:248–249), (13:174–176), (16:575–577). 6 months 3.5 6
18 months 4.0 8
IIA2 3 years 4.5 8
5 years 5.0 10
96. A. Initially, a fiberoptic bronchoscope must be cleaned 6 years 5.5 10
with soap and water. External surfaces, as well as all 8 years 6.0 10
channels, must be mechanically cleaned at this time. 12 years 6.5 12
The endoscope itself (after being separated from the 16 years 7.0 14
biopsy forceps and brushes) can be placed in glu- Adult (female) 8.0–8.5 14
taraldehyde. The biopsy forceps and brushes can be Adult (male) 8.5–9.0 14
sterilized via either ethylene oxide or steam autoclav-
ing. Pasteurization is not suitable for processing endo- (1:594).
scopes, because it does not sterilize.
(1:51–52), (7:713). IIA1f(4)
100. D. Nasotracheal intubation can be accomplished by
IIA1h(4) blind intubation with a nasoendotracheal tube, which
97. C. Pulse oximeters are accurate for oxygen saturations does not require a laryngoscope and a blade. Nasotra-
greater than 80%. Because of the relationship between cheal intubation can also be performed by inserting the
the PO2 and the SO2, along with the steep portion of tube into the pharynx blindly and then guiding the tube
the oxyhemoglobin dissociation curve, pulse oximeter through the larynx with Magill forceps. The design of
saturations less than 80% need to be cross-referenced Magill forceps makes this instrument particularly
with an arterial blood-gas analysis. According to the suited for this purpose.
Health Care Financing Administration (HCFA) guide- (13:166–167), (15:831–832), (16:580, 829–830).
lines, to qualify for oxygen therapy at home, a patient
must have a PaO2 that is less than or equal to 55 torr or IIA1g
an SaO2 that is less than or equal to 85%. To ensure ac-
101. A. The following list represents suction catheter crite-
curate assessment of the patient, an arterial blood-gas
ria. A suction catheter must
analysis needs to be performed. The need for arterial
blood-gas analysis when attempting to establish the 1. offer little resistance to insertion through an ar-
need for oxygen therapy at home is especially impor- tificial airway.
tant for patients who are chronically ill. 2. have a smooth, rounded tip to prevent mucosal
damage.
(1:360–363, 928), (10:96–99), (13:191–195),
3. be of adequate length to extend below an artifi-
(16:310–312).
cial airway.
4. have side holes at the distal end to prevent mu-
IIA1f(1) cosal damage.
98. C. Oropharyngeal airways are indicated only for co- 5. not occlude the airway when inserted (less than
matose patients. Otherwise, the laryngeal reflexes will be 1/2 the internal diameter of the airway).
activated (e.g., gagging, vomiting, and laryngospasm).
The last requirement does not apply to some pediatric
(1:647–648), (5:239), (13:158), (15:826), and neonatal patients, because in some cases, the I.D.
(16:565–567). of the ET tube is so small that a suction catheter less
than 1/2 the I.D. of the ET tube would be ineffective
IIA1f(2) for the removal of secretions.
99. A. Endotracheal tube sizes are based on I.D. to facili- (1:618), (13:182).
tate the selection of a suction catheter. Selection of a
tube one size larger or one size smaller will enable

254 Chapter 4: Equipment

IIA1h(4) If the cylinder volume is known, the pressure-volume
102. B. One of the many factors that adversely influences conversion factor can be determined by dividing the
SpO2 readings is anemia. Because less hemoglobin is cylinder volume in liters by the pressure (psig) in a full
present in circulation, fewer wavelengths of light are cylinder. The time in minutes can then be determined
absorbed by oxyhemoglobin. Hence, anemia causes a by multiplying the cylinder pressure by the cylinder
falsely high SpO2. To obtain a more accurate oxygen factor and then dividing by the flow in liters per minute.
saturation, an arterial blood-gas analysis needs to be cylinder pressure  conversion factor
performed. time in minutes =
flow rate
(AARC Clinical Practice Guidelines, Sampling for
Arterial Blood Gas Analysis), (1:343, 361), (10:97), 900 psi  3.14 liters/psig
=
(13:168–169, 194), (16:311). 6 liters/minute
= 471 minutes
IIA1h(1) 471 minutes = 7.85 hours, or 7 hours and 51 minutes
103. B. A Bourdon gauge is the flow meter to use when a From a clinical standpoint, the pressure gauge on the H
small, compressed gas cylinder is being transported in cylinder must not be allowed to fall below 200 psig.
a horizontal position. The Bourdon gauge has an inter- When the pressure gauge approaches that reading, the
nal curved, hollow tube that uncoils (expands) in re- cylinder must be replaced with a full one. Otherwise,
sponse to the pressure in the compressed gas cylinder. the pressure (less than 200 psig) that is operating the
This tube, in turn, is connected to the needle on the face oxygen-delivery device would be too low to effectively
of the gauge. The uncoiling or expansion of the tube provide an adequate flow rate and FIO2.
and the movement of the needle on the face of the
gauge are not affected by gravity. Therefore, the Bour- (1:722), (5:35–37), (13:45–46), (16:352).
don gauge, although it is not compensated for back
pressure (i.e., indicates a flow rate higher than what is IIA1h(1)
actually being delivered), it can be used in a horizontal 105. A. Air-oxygen blenders require a 50-psig source of
position. both oxygen and air while utilizing an internal pres-
Thorpe tubes, on the other hand, are gravity-dependent sure balancing system to maintain equal air and
and will not register an accurate flow rate reading oxygen pressures at a proportioning valve. The pro-
while in a horizontal position. A flow restrictor is not portioning valve adjusts the amount of air and oxygen
adjustable. A pressure regulator is used to reduce pres- passing through a dual orifice and controls and main-
sure to a working level but does not regulate flow. tains the concentration of oxygen used to supply ven-
tilators, CPAP systems, etc.
(1:731), (5:46), (13:61), (16:359–361).
(1:758–759), (5:43–45), (13:81–84), (16:363–364).

IIA1h(3) IIA1g
104. B. Cylinder conversion factors are based on Boyle’s 106. D. When collecting a sputum sample for carcinoma
law, which describes the relationship between pressure detection, a preservative such as Carbowax is included
(P) and volume (V). According to Boyle’s law, pres- to maintain the integrity of the epithelial cells during
sure and volume are inversely proportional when the transport. Isotonic saline, hypertonic saline, and bacte-
temperature and mass of the gas are constant. Note the riostatic saline will not perform this function.
following relationship:
In addition, you should remember that bacteriostatic
P1V1 = P2V2 saline should not be used in the transport of specimens
Cylinder Size Conversion Factor for microbiologic evaluation. Normal saline (without a
preservative) is used.
622 liters
E = 0.28 liter/psig (15:622–626).
2,200 psig
IIA1i(2)
5,269 liters
G = 2.39 liters/psig 107. C. A CPAP system requires a gas-flow source, a reser-
2,200 psig voir bag, a one-way valve or pop-off, a humidifier, a
pressure manometer, a patient attachment device, and
6,900 liters either a threshold or flow resistor.
H or K = 3.14 liters/psig
2,200 psig (1:865), (5:355–357), (13:353–354), (15:915–917).

Chapter 4: Equipment 255

IIA1g pensive, and a patient is typically attached to a Bourdon-
108. B. Assembly of a sputum specimen-collector system type regulator for only a short time while under super-
for obtaining a sputum specimen from a patient via en- vision.
dotracheal suctioning would have the specimen col- (1:731), (5:46), (13:61), (16:359–361).
lector (trap) placed between the suction catheter and
the suction tubing, which is connected to the vacuum IIA1h(2)
regulator. This setup enables the practitioner to control
110. C. Air compressors provide oil-free air at pressures
the vacuum pressure used to collect the specimen and
high enough to power mechanical ventilators, aerosol-
provides a means for easy removal of the specimen
generating devices, and other respiratory-care equip-
collected from the system.
ment. The other options are not associated with the
(13:184), (16:603–604). function or operation of air compressors. Three types
of air compressors are used in hospitals: piston, cen-
IIA1h(1) trifugal, and diaphragm. Piston and centrifugal com-
109. C. A Bourdon gauge is a pressure gauge consisting of pressors can be used to supply hospital piping systems
a coiled, hollow metal tube that tends to straighten or large equipment, while diaphragm compressors are
when an internal pressure is applied. The coiled tube is primarily used for small appliances.
attached to an indicator needle through a gear mecha- (1:835–836), (5:13–17), (13:381), (16:647).
nism (refer to Figure 4-12). When the cannula tubing
becomes occluded, back pressure causes the coiled IIA1g
tube to straighten farther—indicating a flow greater
than what the patient is receiving. 111. B. Suctioning should be performed only when neces-
sary. Establishing a specific time schedule for suction-
5
6 7 8
9
ing might be detrimental to the patient. Tracheo-
4 10 bronchial suctioning generally should not exceed 15
3 11

2 12 seconds. The risk of removing too much tidal volume

LPM
1
0 14
13
Needle indicating and oxygen increases beyond this time interval. Pre-
flow rate oxygenation helps build a reserve of oxygen in the pa-
Gas outlet tient, while oxygenation after suctioning restores the
blood’s oxygen level.
Source gas
When the suction catheter impinges on the carina, the
Figure 4-12: A Bourdon gauge functioning as a flow meter
can be placed in virtually any position and still function regularly. vagal-vagal reflex can be stimulated, causing brady-
cardia and hypotension. The external diameter of the
Although a Bourdon gauge-type regulator is not as ac- suction catheter should not exceed 1/2 to 2/3 of the en-
curate as a Thorpe tube-type regulator, Bourdon gauge dotracheal tube’s internal diameter. In neonates, how-
regulators are commonly used for several reasons. The ever, this guideline does not apply because of the small
Bourdon gauge regulator will continue indicating the diameter of neonatal endotracheal tubes. For neonates,
flow rate in any orientation; therefore, the cylinder can the largest external diameter catheter fitting easily
be placed on its side. Also, it is typically more durable through the endotracheal tube should be used.
than a Thorpe tube regulator when used in emergency
rescue situations or transport. The gauge is also less ex- (1:154, 286).

STOP
You should stop here to evaluate your performance on the 111 questions relating to matrix sections IIA1 and IIA2.
Use the Entry-Level Examination Matrix Scoring Form referring to equipment. After you evaluate your performance
on matrix sections IIA1 and IIA2, you should continue with the Equipment assessment.

256 Chapter 4: Equipment

IIB2e(2) The major drawbacks to a nasal cannula include the
112. D. NPPV is an excellent alternative for certain pa- following:
tients, as opposed to immediately intubating them and • inability to measure FIO2 that is received by the
establishing conventional mechanical ventilation. Pa- patient
tients who have been successfully treated with NPPV • inappropriate for patients who have chronic hy-
include those who have chronic ventilatory failure percapnia
caused by (1) chest wall deformities, (2) neuromuscu- • inability to deliver high oxygen concentrations
lar disease, (3) COPD, (4) cystic fibrosis, or (5) (upper limit is approximately 45% oxygen)
bronchiectasis. Patients who have acute ventilatory
failure and who respond favorably to NPPV include Table 4-11 provides an approximation of the FIO2 de-
those who have ARDS, pneumonia, cardiogenic pul- livered by a nasal cannula at various liter flows.
monary edema, heart failure, obstructive sleep apnea, Table 4-11: Cannula flow rates and corresponding
asthma, or COPD (acute exacerbation). FIO2s
(1:895, 982, 1122, 1128), (10:192, 399), (16:616, 1137). Oxygen Flow Rate
(liters/minute) Approximate FIO2
IIB2j
1 0.22 to 0.24
113. C. If mist is not entering the enclosure, the problem is
2 0.23 to 0.28
likely the nebulizer. Ensuring that the canopy sides are 3 0.27 to 0.34
tucked under the mattress and that the zipper is closed 4 0.31 to 0.38
has nothing to do with the aerosol output. These mea- 5 to 6 0.32 to 0.44
sures need to be taken to ensure that the FIO2 remains
reasonably stable and that the mist remains within the
enclosure. They do not, however, influence the output Because the patient was on an FIO2 of 0.28, the CRT
of mist from the device. Considerations regarding the should establish a liter flow of approximately 2 to 3
output of mist include keeping the reservoir appropri- liters/minute.
ately filled and cleaning the nebulizer’s jet. At flow rates higher than 6 liters/minute, the nasal can-
(1:759–760), (13:68), (16:395), (23:83–86). nula will dry nasal secretions and cause patient dis-
comfort. In addition, convention dictates that a patient
IIB1a can still mouth breathe while wearing a cannula and
continue to receive benefit, because the oxygen filling
114. B. Some confusion exists concerning the classification the nasal cavity, nasopharynx, and oropharynx will be
of oxygen-administration devices. Scanlan categorizes entrained by air entering the patient’s mouth. Some
oxygen-administration equipment into three main cat- clinical studies have demonstrated that the FIO2 re-
egories: low-flow devices, devices using reservoirs, ceived by the patient can decrease during mouth
and high-flow devices. Burton has two divisions: low- breathing.
flow devices and high-flow devices. Low-flow systems
only supply a portion of the patient’s tidal volume, and (1:473–474), (5:54–59), (13:66–67), (16:381–383).
as a result, the oxygen percentage the patient receives
is determined by his inspiratory flow rate, inspiratory IIB2m
tidal volume, nasal and oral pharyngeal volume, and 115. D. When having a tracheotomized patient perform an
the flow rate set on the flow meter. As a patient’s tidal MIP maneuver, the CRT should be aware that occlud-
volume increases, the effective FIO2 decreases— ing the breathing port (preventing contact with the at-
because the patient must now inhale more room air in mosphere) is essential. The internal mechanism of the
order to meet his inspiratory demands. Similarly, a re- apparatus is similar to an aneroid barometer. Both a di-
duction in the patient’s tidal volume (following seda- aphragm and an evacuated container move in response
tion, for example) will result in an increased FIO2 to negative pressure, causing the needle on the face of
being delivered to the patient. the manometer to change position. Rupture of the di-
A nasal cannula is a low-flow system and provides a aphragm or of the evacuated container will render the
number of advantages over oxygen-administration de- device unusable.
vices incorporating a mask as part of their design. (1:825, 971), (16:234–235).
Some advantages are as follows:
• provides more comfort than masks IIB2h(3)
• affords the opportunity to eat while in use 116. B. Area alarms are situated in CCUs, operating rooms,
• enables long-term use in the home and recovery rooms. These alarms are audible and
visual. The visual alarm cannot be canceled. An area

Chapter 4: Equipment 257

 alarm is triggered when the operating line pressure in- the high pressures. Changing the FIO2 on the blender
creases or decreases by 20% or more from the normal has no effect on airway pressures.
operating pressure.
(5:503–507), (13:431–436).
(1:722–724), (5:28–30), (13:29), (16:346).
IIB1h(3)
IIB1a(1) 120. D. The most appropriate response at this time is to en-
117. D. The nasal cannula is usually a reliable piece of sure patient safety. Thus, the CRT should shut off the
equipment. Occasionally, however, problems arise. oxygen zone valve to the west wing and provide emer-
These problems are generally easy to detect and cor- gency oxygen to all of the oxygen patients who have
rect, however. To begin, the tubing of the cannula can been relocated from the west wing.
twist or kink, causing a reduction of gas flow. The can-
(1:724–725), (13:32–35).
nula might have become disconnected from the flow
meter (no humidifier while operating at less than 4
liters/min.) or from the humidifier (humidification IIB2a(2)
while operating at 4 to 6 liters/min.). The humidifier 121. D. The CRT should note whether or not mist disap-
jar itself might not be sealed or tightened completely, pears from the outflowing gas during patient inspira-
causing gas to leak from the system. The flow meter it- tion. If this situation occurs, the patient’s inspiratory
self also might be inaccurate. demands are exceeding the flow provided by the de-
vice, and the patient will inspire room air through the
(1:748), (7:406), (13:57), (16:382–383). distal end of the T-piece. As a result, the patient’s FIO2
will fall. The incorporation of an additional piece of
IIB1b aerosol tubing at the distal end of the T-piece will pro-
118. A. A hygroscopic condensing humidifier (HCH) is one vide a reservoir for oxygen and will provide a more ac-
of three types of HMEs. The other two types of HMEs curate FIO2. Refer to Figure 4-13.
are simple condenser humidifiers and hydrophobic
condenser humidifiers. The HCH incorporates a con- Briggs adaptor
densing element of low thermal conductivity. The con- Aerosol tubing Reservoir tubing
densing element is made of paper, wool, or foam and
contains a hygroscopic salt for holding more moisture
from the patient’s exhaled gas. The HCH is specifi-
cally contraindicated in patients who have copious se- From aerosol generator
cretions. Any humidifier in the circuit with an HCH
in-line should be unheated. Addition of a second or
third HCH in tandem has been tried to increase the ef-
fectiveness of these units. In the situation presented
To patient
here, tandem HCHs could still be occluded by this pa-
tient’s copious secretions. Thus, replacing the HCH Figure 4-13: An aerosol T-piece is attached to an ET tube
with a segment of reservoir tubing connected to the distal
with a heated humidifier is the best course of action in end of the T-piece, to help stabilize the FIO2 by eliminating
this circumstance. room-air entrainment when the patient inspires.
(1:665–666), (5:117–118), (13:123), (15:798–799), If the aerosol tubing serving as the reservoir is too
(16:429–431). long, the patient might rebreathe carbon dioxide. Fig-
ure 4-14 illustrates that the gas exhaled from the respi-
IIB1e(1) ratory tract has a low level of carbon dioxide, because
119. C. Occlusion of the expiratory limb of the breathing the gas comes from the anatomic dead space.
circuit or kinking of the exhalation valve charging line
Once this gas is exhaled, mixed gas from the airways
will disable the inspiratory-relief valve, which will en-
and alveoli exit, followed by pure alveolar gas. An in-
able dangerously high airway pressure to build up in
crease in the patient’s ventilatory rate or tidal volume
the circuit and in the patient. A PIP relief valve exists
should alert the CRT that the patient might be re-
that is adjustable and set at the factory at 88 cm H2O.
breathing CO2.
This pressure-relief valve should be adjusted to fit the
needs of a particular patient in order to decrease the The aerosol T-piece or Briggs adaptor is used to de-
achievable pressures from this kind of incident. Oc- liver aerosols to patients who have endotracheal or tra-
clusion of the inspiratory limb would block ventilation cheostomy tubes. Although this practice is cited as
to the patient, but the patient would not be exposed to relatively safe, any device that employs an aerosol in-

258 Chapter 4: Equipment

 creases the risk of causing microbial contamination, IIB1e(1)
overhydration, and bronchospasm. The risk of 124. B. To calculate the volume compressed in the ventila-
bronchospasm is especially great if the patient has an tor circuit after each breath is delivered by a preset vol-
underlying history of asthma. Although more expen- ume ventilator, the following three factors must also be
sive, a humidifier (a device that does not produce an known:
aerosol but adds water vapor to the air the patient in-
spires) is more prudent for patients who cannot toler- 1. tubing compliance (Ctubing)
ate bland aerosol. 2. PIP
3. PEEP
(13:78), (16:391–394).
The ventilator tubing is analogous to the lung’s anatomic
Aveolar and Anatomic dead space. Each time we inspire, a certain volume of air
Deadspace Gas remains in the anatomic dead space (mouth and nose to
Anatomic Mixture
Aveolar terminal bronchioles). This air does not reach the alveoli.
Deadspace Gas When a ventilator delivers a preset volume with each
tidal-volume delivery, the entire volume does not enter
the patient’s lungs. A portion of the preset volume re-
Exhaled CO2%

mains in the ventilator tubing at end-inspiration. The

formula for determining the volume lost (Vlost) in the
ventilator tubing is shown as follows.
Vlost = (PIP  PEEP)Ctubing
For example, assume a hypothetical tidal volume of
800 cc is delivered to the patient. The PIP achieved
during inspiration is 40 cm H2O. The patient is receiv-
ing 10 cm H2O PEEP. The tubing compliance is 3
Start of exhalation cc/cm H2O.

Figure 4-14: Normal exhaled CO2 curve illustrating Inserting the known values into the formula, we obtain
changes in the % exhaled CO2 throughout the expiratory the following:
phase.
Vlost = (40 cm H2O  10 cm H2O)3 cc/cm H2O
IIB2h(4) = (30 cm H2O)(3 cc/cm H2O)
122. C. A number of problems can cause the exhaled CO2 = 90 cc
level to fall and be continuously maintained at zero.
These problems include a low or absent cardiac output, The volume compressed in the ventilator tubing at the
a disconnect in the system, and esophageal intubation. end of inspiration is 90 cc. The patient’s delivered tidal
Based on the patient’s arterial blood-gas data, a system volume (VT) is, therefore,
disconnect is likely. The arterial blood-gas data are too delivered VT = exhaled VT  Vlost
good for the patient to have a cardiac arrest or
esophageal intubation. = 800 cc  90 cc
(1:363–367), (5:315–317), (13:197–198), = 710 cc
(10:99–102), (16:313–314). (1:937), (2:519–521), (7:695–696), (10:247,
257–258), (16:1127).
IIB1h(4)
123. C. To calibrate a transcutaneous CO2 electrode, a high IIB2e(2)
and a low CO2 gas concentration are needed—along 125. A. NPPV can often be used to avoid (or at least stall)
with knowing the barometric pressure. Typical CO2 the need to intubate certain patients who require me-
gas concentrations are 5% and 10%. These gas con- chanical ventilatory assistance in both acute care or
centrations are introduced into the electrode. long-term settings. NPPV can be delivered by using a
To calibrate a transcutaneous PO2 electrode, two cali- nasal mask or a face mask. The IPAP and the EPAP are
bration points are also used. The low calibration point independently preset.
is a solution, usually sodium sulfite, containing 0% O2. If the IPAP and EPAP preset pressures fail to be
The second point is room air, i.e., 21%. Sometimes the achieved, the following conditions need to be consid-
high O2 gas contains 12% oxygen instead of 21%. ered:
(1:354–356), (5:292), (13:189–190).

Chapter 4: Equipment 259

 • Are there leaks in the system? more room air will be entrained through the ports on
— Check the nasal/face mask. the mask. The amount of room air breathed in through
— Check the tubing connections. the mask’s ports will likely not equal the amount of
room air that would have been entrained if the bed
• Is the filter dirty?
sheet was not obstructing the air-entrainment ports.
— Clean the filter.
Consequently, the FIO2 will ultimately increase.
— Replace the filter.
• Is the delay or ramp on? Entrainment window
— Allow time for the pressure or flow to increase.
Each of these components needs to be checked when
either the flow rate or the IPAP and/or EPAP pressures
is incorrect compared to the preset values.
(1:1122–1125), (5:569–574), (13:449–452), (16:61). Outflow jet

IIB2h(2) Detail of jet tip

(Low FlO2)
126. B. Air compressors are relatively easy to troubleshoot.
Generally, if the air compressor malfunctions, the de- Detail of jet tip
vice needs to be sent to the biomedical equipment de- (High FlO2)
partment for repair. If the air compressor has a low
Figure 4-15: Room-air entrainment port of a Venturi mask
output, however, certain areas can be examined to lo- with insets detailing a high and low FIO2 jet tip. The opened
cate the source of the problem. To begin, the air inlet (white) area within the blackened region of jet tips shown
filter should be viewed, because it might need cleaning represents the lumen through which O2 flows
or replacing. The tubing or hoses connecting the air Although the Venturi mask provides an accurate FIO2,
compressor to the attached equipment might be loose, this mask is a high-flow device and uses a large
obstructed, or leaking. All of the fittings need to be amount of oxygen. Consequently, it would not be cost
tightened and checked for leaks. effective for use in the home.
Air compressors do not operate off a 50-psig air Table 4-12 summarizes the air-to-oxygen entrainment
source. They are electrically operated and produce ratios for air entrainment masks at their recommended
pressures of 45 to 55 psig themselves. They commonly liter flows. The total flow is included.
deliver flow rates ranging between 60 and 80 liters/
min. Table 4-12: Correlation among FIO2, AIR/O2, source flow,
and total flow for a venturi mask
(5:13–17), (13:43).
Air:Oxygen O2 Flow Meter Total Flow
FIO2 Ratio (liters/minute) (liters/minute)
IIB1a(2)
127. A. Air entrainment masks determine the FIO2 that the 0.24 25:1 4 104.0
patient receives by varying two aspects of the entrain- 0.28 10:1 4 44.0
ment port’s construction: (1) the diameter of the out- 0.35 5:1 8 48.0
flow jet, and (2) the size of the entrainment window. If 0.40 3:1 10 40.0
0.50 1.7:1 12 32.4
the liter flow from the flow meter is kept constant, de-
creasing the air entrainment mask’s outflow port’s di-
ameter will increase the velocity of the gas. Recall The total flow rate received by the patient is obtained
from basic gas therapy that the higher the forward ve- by adding the parts comprising the air:oxygen ratio
locity of a gas, the lower the gas lateral wall pressure. and multiplying the sum by the oxygen flow meter set-
This pressure drop causes room air to be drawn ting. For example, calculate the total flow delivered by
through the entrainment windows. The greater the ve- an air entrainment mask set at 24% oxygen, operating
locity of the 100% oxygen, the more room air that is at a flow rate of 4 liters/minute.
entrained. Conversely, the smaller the entrainment
window, the less room air entrained—and the higher STEP 1: Add the parts of the air:oxygen ratio.
the resulting FIO2. Refer to Figure 4-15. 25 parts air + 1 part oxygen = 26 total parts
Therefore, with the bed sheet (or the patient’s gown, in STEP 2: Calculate the total flow.
some cases) covering the air-entrainment ports, the to-
tal liter flow delivered to the patient will decrease. The (4 liters/minute)(26) = 104 liters/minute
FIO2 then received by the patient will increase, and (1:754–755), (5:49–53), (13:76–77), (16:390–391).

260 Chapter 4: Equipment

IIB1i(2) stricting flow through the mouthpiece might increase
128. D. The major problem associated with ventilators that the patient’s WOB. Decreasing the patient’s goal is
are not PEEP compensated when in the assist/control counter-productive to therapeutic objectives.
mode is potential ventilator self-cycling because of a (5:186–187).
circuit leak. The leak causes a loss of system pressure.
When the PEEP pressure is reached, the ventilator IIB1a(2)
self-cycles—increasing the patient’s ventilatory rate.
133. B. An oxyhood provides a number of advantages over
Additionally, a defective PEEP valve can also cause
an oxygen tent and an oxygen mask in the delivery of
self-cycling through loss of pressure. The tidal volume
oxygen to infants. The oxyhood provides an accurate
setting has nothing to do with the problem. The assist
and stable FIO2 while still providing access to the in-
sensitivity setting of –2 cm H2O below the PEEP level
fant for various procedures. Masks are poorly tolerated
is appropriate.
by infants; however, the CRT should observe a number
(5:475–480). of precautions when applying the oxyhood:
1. The gas should be humidified and warmed to pre-
IIB1c vent the following adverse conditions:
129. C. Because heat energy is added to the gas stream a. damage to the infant’s respiratory mucosa
when the water is nebulized, the temperature of the gas b. hypothermia
that is delivered to a patient by an ultrasonic nebulizer c. increased oxygen consumption
ranges between 3ºC to 10ºC greater than room tem- d. increased insensible water loss
perature. This situation is normal; therefore, no prob-
lem exists. Ideally, the CRT should use an oxygen blender to
maintain a constant FIO2.
(1:675–676), (5:154–163), (13:121–122),
(15:803–804), (16:462–465). 2. The incoming gas flow must not be pointed directly
at the infant’s head.
IIB1f(2) 3. Flows should be no less than 5 to 7 liters/minute to
130. A. Nasal ET tubes are said to be better suited for long- prevent carbon-dioxide buildup within the hood.
term airway management, better tolerated by the pa- 4. Noise inside the hood can damage an infant’s hear-
tient, and less prone to kinking because they are more ing. Water within the tubing will increase the noise
stable within the nasal cavity. Subsequently, respiratory- levels, and if a large-volume nebulizer with open en-
care equipment can be attached more comfortably and trainment ports is used to deliver a specified FIO2,
securely. the resulting FIO2 will increase. Many CRTs will re-
(1:590, 599–601), (5:240–241), (13:163–165), move the bubble-diffuser tower from Cascade® hu-
(16:570, 830). midifiers to decrease the noise within the oxyhood.
(1:394–395), (5:75–77), (13:79–81).
IIB1h(5)
131. A. The most appropriate initial intervention is to check IIB1e(2)
the calibration of the analyzer against known controls. 134. B. The Puritan-Bennett Companion 320 I/E bipap sys-
This procedure can be done by exposing the analyzer tem has an IPAP range of 3 to 30 cm H2O. Its EPAP
to atmospheric conditions and assuring a reading of level can be adjusted between 3 and 20 cm H2O. The
21%, then subjecting the analyzer to 100% oxygen and Respironics BIPAP® S/T Ventilatory Support System
adjusting it if necessary to 100%. Only after these ini- has an IPAP and EPAP range between –4 and 20 cm
tial steps are taken would one suspect inaccuracy or H2O. For both of these noninvasive positive-pressure
take the unit out of service or perform maintenance. ventilators, the IPAP must be set higher than the EPAP.
(5:281–282), (11:395–398), (13:248). (5:569–574), (13:449–452).

IIB1k IIB2h(4)
132. A. The purpose of the flow indicator is to encourage 135. A. Considerable disparity exists between the PaO2 and
the patient to maintain a lower flow rate to promote the PtcO2. In fact, the only factor that can account for
more uniform distribution of air throughout the lungs. such a high PtcO2 is an air bubble at the electrode. The
Encouraging the patient to take a slower inspiration PO2 of room air is 159 torr. Consequently, the elec-
will lower the flow indicator. Increasing the length of trode is sensing the PO2 in the room air and is display-
the tubing, decreasing the diameter of the tubing, or re- ing that value on the monitor. None of the other factors

Chapter 4: Equipment 261

 listed in the question would cause the PtcO2 to rise to • The flow rate of the gas might be insufficient.
159 torr. • Water (condensate) might have accumulated in the
delivery tubing (higher delivered FIO2).
(1:356), (5:292–293), (13:188–190), (10:102–105).
• A leak can occur anywhere in the system (lower
delivered FIO2).
IIB1h(4) • The length of the delivery tubing might be extraor-
136. A. The following situations can cause a low PETCO2 to dinarily long (higher delivered FIO2).
be displayed on a capnogram: • The air-entrainment port might be restricted
• an improperly placed endotracheal tube (higher delivered FIO2).
(esophageal intubation) • The delivery tubing might be obstructed or kinked
• an uncalibrated monitor (higher delivered FIO2).
• an obstructed sidestream tube (applies only to side- A low water level in the reservoir, an obstruction in the
stream capnographs) capillary tube in the reservoir, and a defective baffle
• a malfunctioning sensor would all cause a decreased aerosol output but would
• cardiac arrest not affect the FIO2 of the device.
• hyperventilation
• disconnection from the ventilator (1:755–758), (5:132), (13:67–68).
• a loose connection or leak in the circuit
• obstruction of the endotracheal tube IIB2a(2)
139. D. Mist tents contain numerous sources of leaks. The
Patient movement and the sensor position do not cause
leak sources can cause room air to lower the FIO2 of
a low PETCO2 value. Patient movement might increase
the enclosure. All of the tubing needs to be securely
carbon dioxide production. Sensor position affects re-
connected, as well as having the bottom of the plastic
sponse time. The closer the sensor is to the patient’s
canopy firmly tucked under the mattress. The zipper
mouth, the faster the response time, and vice-versa. An
on the canopy must be completely closed. Another fac-
increased cardiac output produces a higher PETCO2.
tor that disturbs the FIO2 of the enclosure is frequent
Conversely, a low cardiac output causes a low PETCO2.
intrusions caused by health-care personnel. Parents
(1:363–367), (5:315–317), (13:197–198), sometimes will open the canopy to interact with their
(10:99–102), (16:313–314). child. If the child is active, this movement might cause
the plastic canopy to dislodge from under the mattress
IIB1c and produce a leak.
137. C. Aerosol output from a jet nebulizer can be de- Controlling the FIO2 of a mist tent is a challenge to the
creased by the following factors: CRT, because numerous factors influence the security
• a loose DISS connection between the nebulizer and of the enclosure. If the opening and closing of the
the flow meter canopy is kept to a minimum, however, and if all of the
• a low flow-rate setting on the flow meter sources of leaks are secured, the FIO2 should fluctuate
• an obstruction of the jet less.
• an empty nebulizer reservoir or low water level in (5:78–79), (7:479–481), (13:68), (16:461).
the nebulizer reservoir
• kinked or obstructed tubing IIB2f(2)
• a loose nebulizer jar lid
140. B. If the cuff inflation line (i.e., tubing between the
• accumulation of water (condensate) in the tubing
cuff and the one-way valve/pilot balloon) of an endo-
• a high FIO2 setting on the nebulizer (0.70 or greater)
tracheal or tracheostomy tube is severed, the cuff will
Not having a water-collection bag attached to the tub- deflate. The elastic recoil of the cuff will force air to
ing at the most gravity-dependent area can cause water leave the cuff and vent to the atmosphere through the
(condensate) to accumulate in the tubing. If the situa- open-cuff inflation line.
tion is corrected soon enough, however, water accu-
Obviously, the tube needs to ultimately be replaced. The
mulation in the tubing will not be a factor.
tube can be temporarily maintained in position, how-
(5:128–132), (13:104–107). ever, to allow time for gathering the necessary equip-
ment for reintubation. By inserting a needle attached to
IIB1a(2) a stopcock and a small-volume syringe, the CRT can in-
138. A. The delivered FIO2 from an air-entrainment device ject air into the cuff and keep it inflated until the tube is
will differ from the FIO2 that is dialed in or set at the removed. The setup is illustrated in Figure 4-16.
air-entrainment port for the following reasons: (Respiratory Care, Vol. 31, pp. 199–201, 1986), (13:133).

262 Chapter 4: Equipment

 Severed one-way valve and inflating tube IIB2g
143. C. In this situation, the CRT has likely overlooked clos-
ing the irrigation port of the closed-suction catheter sys-
stopcock tem after irrigating the patient’s tracheobronchial tree
with 5 cc of normal saline. This omission could likely

10
1
2
3
4
5
6
7
8
9
account for the sudden decrease in the PIP from 35 cm
needle H2O to 15 cm H2O. The diameter of the irrigation port is
10-mL syringe
not large enough to cause the PIP to drop to 0 cm H2O.
On the other hand, disconnection of the patient wye from
deflated cuff the endotracheal tube adaptor of the closed-suction
catheter system would cause the PIP to drop to 0 cm H2O.
If the patient developed bronchospasm, the PIP would be
greater than 35 cm H2O and not less than 20 cm H2O.

Figure 4-16: Technique for temporarily maintaining cuff in- The patient has not yet been suctioned. Therefore, the
flation when the line between the pilot balloon and the ET effect of the removal of secretions from the PIP would
tube cuff is severed. (Respiratory Care, 1986; 31: 199–201). not have yet occurred. Furthermore, that the removal
IIB1e(1) of secretions would account for a fall in PIP from 35
141. D. The terminal flow control, when activated, provides a cm H2O to 15 cm H2O is highly unlikely. A PIP of 15
flow of gas below the Bennett valve. This additional gas cm H2O would likely be insufficient to maintain ade-
flow helps close the valve. The terminal flow control quate ventilation. A leak in the system is most likely
should be activated when minor leaks occur in the system. causing the problem.
For example, if a patient has a difficult time creating a seal (1:618–619), (15:836), (16:605).
around the mouthpiece, the terminal flow control can
compensate for the gas escaping through the patient’s lips. IIB2h(1)
Essentially, the terminal flow control is used to assist
144. D. The principle of operation of a Bourdon gauge lies
in cycling off the machine and helps terminate inspiration.
in the fact that as pressure increases, flow from the re-
(5:209–210), (13:256–257). ducing valve and the fixed orifice causes the hollow
coiled tube to straighten. The gauge, however, is recal-
IIB1a(2) ibrated to indicate flow (volume/time), rather than
142. C. The total flow rate of gas to the patient is an impor- pressure, as the coiled tube straightens. The Bourdon
tant consideration in maintaining a known FIO2. Be- gauge employs Poiseuille’s law of laminar flow.
cause of the size of the jet in the nebulizer, the (1:731–733), (5:46), (16:360–361).
maximum inlet flow of pneumatic nebulizers is some-
where between 12 liters/minute and 15 liters/minute. IIB1q
Assuming the higher flow rate, i.e., 15 liters/minute at
145. A. Because of the size of the material coming from the
40% oxygen (air:oxygen ratio of 3:1), the total flow to
stomach, a –80 mm Hg vacuum is probably inade-
the patient is 60 liters/minute. At 60% oxygen
quate. Increasing the level of suction will aid in the re-
(air:oxygen ratio of 1:1), the total flow is only 30
moval of secretions. A size 12 French suction catheter
liters/minute. Because the peak inspiratory flow rate
would be too narrow to remove the vomitus. The con-
for a normal person is about 25 to 30 liters/minute, one
necting tube leading to the suction collection bottle is
should strive for at least 40 liters/minute from the gas
inappropriate and cannot be placed easily into the back
source. Because this flow rate is not possible from a
of the throat to clear any secretions. Finally, looking
single nebulizer, the flow rate must be augmented.
for a new Yankauer suction device will waste valuable
This augmentation can be accomplished either by
time and will delay the intubation procedure.
adding the flow rate from a second nebulizer or by
keeping the nebulizer diluter control set at 40% (thus A Yankauer suction device is essentially a curved piece
maintaining the total flow at an acceptable level) and of plastic with a rounded tip and a suction-control
bleeding in oxygen to achieve 60%. A few newer neb- thumb port. After setting the appropriate level of suc-
ulizers, such as the MistyOx, have the capability of de- tion (–100 to –120 mm Hg), insert the device into the
livering higher flow rates at higher FIO2 s. patient’s mouth and cover the thumb port to apply suc-
tion. The CRT should not suction far into the orophar-
(1:756–757), (5:131–138), (13:77–78), (15:882–885),
ynx for fear of stimulating the patient’s gag reflex and
(16:392).
eliciting another vomiting episode.
(1:616), (16:604).

Chapter 4: Equipment 263

IIB2f(3) nebulizer cause less room air to be entrained through
146. A. Neither overinflating the cuff, a pneumothorax, nor the air-entrainment port. The consequence of less
the presence of tracheobronchial secretions is a cause room-air entrainment is a lower aerosol output.
for the low-pressure alarm to sound. If the CRT over- A full water trap itself will not reduce the aerosol out-
looked reinflating the cuff, volume from the ventilator put if the condition is discovered and rectified before
would escape around the tracheostomy tube, causing water begins to accumulate in the tubing.
the low pressure alarm to sound with each inspiration.
A pneumothorax and the presence of airway secretions (5:128–130), (13:104–107).
would likely activate the high-pressure alarm.
IIB1a(2)
(1:614–615), (5:248), (13:130–131), (16:634).
151. A. For an HME to work effectively, the patient must
IIB1a(2) exhale through the HME and receive his next breath
through the HME, as well. The following physical
147. B. If the gas flow is less than 6 to 7 liters/minute, fluc-
variables will affect an HME’s performance:
tuations in the FIO2 can occur—although some clini-
cians believe that 10 to 15 liters/minute of gas flow are • the temperature and humidity level in the
needed. Gas layering can occur inside an oxyhood, inspired air
causing the lower areas to have a higher FIO2 than the • inspiratory and expiratory flow rates (the higher the
layers near the top. If the oxyhood is too large for an flow rate, the lower the exchanger’s efficiency)
infant, room air can leak into the enclosure and dilute • the larger the internal interface, the greater the effi-
the oxygen concentration entering the oxyhood. ciency (unfortunately, the larger the internal interface,
the greater the mechanical dead space that the device
(1:394–395), (5:75–77), (13:79–81), (15:1046).
imposes on the patient. For small children, this might
be unacceptable and dramatically increase their WOB)
IIB1h(4) • good thermal conductivity of material within the
148. A. To prevent thermal injury from a transcutaneous exchanger and poor conductivity of the exchanger’s
oxygen electrode, the sensor site must be regularly housing
changed. The recommendation for changing sensor
sites is every two hours for neonates and every two to HMEs are simple to use, low in cost, and electrically
four hours for adults. safe. Patients who are dehydrated, hypothermic, or
who are experiencing retained secretions, however, are
(1:356), (5:293), (13:190), (10:104). not candidates for HME units. As mentioned earlier,
the HME might have a considerable amount of me-
IIB2h(2) chanical dead space that would preclude its use in mar-
149. C. Whenever the ON/OFF switch on an oxygen concen- ginally weanable patients. Signs of retained or
trator is in the ON position and the power light remains increased viscosity of secretions should alert the CRT
unlit, three possibilities need to be explored. First, deter- that he should use a different type of humidifier.
mine that the concentrator is plugged into a 120-volt out- (1:665–667), (5:117–118), (13:123–124), (16:429–431).
put. Next, determine the status of the outlet. Use a lamp
or a radio known to work, and test the outlet. Then, press
the reset button on the concentrator to ascertain whether IIB1d
a circuit breaker on the device has tripped. These actions 152. D. Mouth-to-mask ventilation (Figure 4-17) offers many
are suggested when troubleshooting this problem. advantages over mouth-to-mouth ventilation, especially if
the mask incorporates a one-way valve to direct exhaled
In addition to the power light not lighting, an audible gas away from the person who is providing mouth-to-
alarm will sound, alerting the CRT to this condition. mask ventilation. An oropharyngeal airway will help
(5:20, 23), (13:43–44). maintain a patent airway. Also, the airway is maintained
by elevating the victim’s mandible with upward pressure
IIB1c applied by the index, middle, and ring fingers to elevate
the mandible and to deliver downward pressure on the
150. A. The aerosol output of a jet nebulizer can be re-
mask from the opposing thumbs.
duced by a loose DISS connection between the neb-
ulizer and the flow meter, a low flow rate setting on Inspired oxygen concentrations can be enhanced by di-
the flow meter, an obstruction of the jet, an empty or recting oxygen flow into the mask via oxygen tubing
low water level in the nebulizer reservoir, a loose attached to an inlet connector. Gastric insufflation can
nebulizer jar lid, and the accumulation of water in be avoided by having a trained assistant apply pressure
the aerosol tubing. Also, high FIO2 settings on the to the cricoid cartilage.

264 Chapter 4: Equipment

 When selecting a catheter, the catheter should never
be more than one-half the internal diameter of the
endotracheal tube. This guideline does not apply to
neonates, however. The largest suction catheter possi-
ble should be used; otherwise, the diameter of the suc-
tion catheter would be extremely small. The maximum
diameter of the catheter in French measurement is cal-
culated by multiplying the internal diameter of the en-
dotracheal tube by three and dividing by two.
Recommended vacuum pressures for adults, children,
and infants are as follows:
• adults: –100 mm Hg to –120 mm Hg
• children: –80 mm Hg to –100 mm Hg
• infants: –60 mm Hg to –80 mm hg

Figure 4-17: Mouth-to-mask ventilation of the patient. The suctioning protocol includes the following tasks:
(American Heart Association, Textbook of Advanced • selection of the appropriate catheter and vacuum
Cardiac Life Support, 2nd ed., 1990, p. 36). pressure
• washing hands
• preoxygenating and hyperventilating the patient
• double gloving
IIB1f
• use of eye shields, gowns, and masks
153. D. Checking the connections at the catheter and col- • monitoring the patient’s SpO2 and ECG if possible
lection container are appropriate actions to take. Nei- • lubrication of the catheter with water-soluble lubri-
ther increasing the negative pressure of the wall cant (only during nasotracheal suctioning). Never
suction to –120 mm Hg, replacing the suction catheter, use water-soluble lubricants when suctioning an
nor adding a water-soluble lubricant to the catheter tip endotracheal tube or tracheostomy tube. If lubrica-
has anything to do with the inability of the CRT to tion is necessary, use sterile water or sterile saline.
achieve suction at the catheter tip. • advancing the catheter until an obstruction is met,
Hypoxemia and hypercarbia are associated with suc- withdrawing slightly, and then applying suction
tioning. The magnitude of hypoxemia that can occur while removing the catheter
during suctioning is affected by the following factors: • providing post-suctioning hyperventilation and
oxygenation
• suction duration
• time intervals between suctioning (1:616–619), (16:600–604).
• suction flow/pressure (vacuum) level
• the suction catheter’s outside diameter
• duration of pre- and post-oxygenation
IIB2h(2)
• number of hyperinflations and the size of the 154. C. When troubleshooting a portable liquid-oxygen
inflation volumes system for a reservoir not delivering oxygen, you
• the concentration of oxygen supplied with pre- and should take the following steps:
post-oxygenations 1. Ensure that the reservoir is full by checking the
In addition, there are numerous additional complications weight scale (or other gauge incorporated into
associated with suctioning, including the following: the device by the manufacturer).
2. Check all the system connections for leaks by
• hemodynamic changes, including hypotension
feeling and listening for escaping gas.
resulting from vagal stimulation or hypertension
3. Examine the humidifier for leaks, loose connec-
caused by hypoxemia
tions, and obstructions.
• atelectasis
4. Check the oxygen tubing for leaks, loose con-
• cardiac dysrhythmias
nections, and obstructions.
• bronchoconstriction
• increased intracranial pressures Portable liquid-oxygen systems are not electrically op-
• cardiac arrest and death erated, nor are there filters to check.
• contamination of the airway
(5:23–28), (13:28–29), (16:896–897).
• tracheal tissue damage

Chapter 4: Equipment 265

IIB2i(2) First of all, a problem with heat loss along the tubing
155. D. When using a continuous-flow system, a high flow occurs when heated gas leaves a heated humidifier and
(usually higher than 60 liters/minute) is necessary to passes through tubing exposed to room temperature.
ensure that airway pressure is maintained. If the pa- This problem is exaggerated if the tubing is especially
tient’s inspiratory flow exceeds the flow through the long or if the transit time through the tubing is espe-
system, the manometer will swing toward the nega- cially slow (which is the situation described here).
tive—increasing the patient’s WOB. A continuous- These situations extend the time of exposure of the
flow CPAP system can use either a threshold resistor heated gas to room temperature and therefore result in
or a flow resistor. Replacing the manometer or discon- greater heat loss.
tinuing the system are not viable options, because they Second, a servo-controlled humidifier has the sensor at
would not correct this problem. Flow is thought to be or near the patient wye on the inspiratory limb of the
inadequate for a CPAP patient when the pressure circuit. As such, it will add whatever heat is necessary
manometer decreases by more than 2 cm H2O during to the humidifier in an attempt to compensate for heat
inspiration. loss along the tubing. Limits are imposed as to how
(1:786), (15:1053), (16:534). much heat the humidifier can safely accept, however.
Usually, if dangerous heat levels are required, the hu-
IIB2f(3) midifier will generate an alarm and the temperature at
the sensor will not reach the set temperature.
156. B. In this scenario, the most likely cause for both the
patient’s dyspnea and the CRT’s inability to pass a suc- Regarding the patient who is receiving CPAP in this
tion catheter is the crusting or accumulation of secre- question, the patient’s ventilatory rate (6 breaths/
tions inside the tube. Shiley tracheostomy tubes have minute) and tidal volume (450 ml) are rather low. The
removable inner cannulas (either permanent or dispos- patient’s minute ventilation is only 2.7 liters/minute,
able). Therefore, the inner cannula needs to be re- i.e., 0.45 liter  6 breaths/minute = 2.7 liters/minute.
moved and inspected. A replacement should be ready The overall gas flow rate through the system is likely
for use at the bedside for this purpose. insufficient to adequately warm the sensor, although
the gas flowing through the circuit might be at the
(1:615), (16:580–581). proper temperature.

IIB2e(1) (1:667–668, 865), (5:107–109).

157. D. A usual response to a ventilatory alarm is to discon-
nect the patient and immediately begin manual ventila- IIB2h(1)
tion while calling for assistance. In this way, the patient 159. B. Figure 4-18 illustrates the alarm module of a
is minimally compromised during a search for me- Sechrist air-oxygen blender. Both source gases enter
chanical malfunction. The situation described here, the alarm module first. If either gas’s pressure exceeds
however, is a common occurrence with the Bear Venti- that of the other by more than 10 pounds per square
lators (models 1, 2, and 3). The cause is almost always inch-gauge (psig), gas flows through a central channel
water that has condensed on the ultrasonic transducer and activates the alarm reed.
and/or receiver of the vortex shedding flow sensing de-
vice (pneumotach) that measures exhaled tidal volume. Spring
The appearance of the patient and the manometer Check valve
swings in pressure should have assured the CRT that
the patient was receiving adequate ventilation. Movable
piston
(5:406), (13:407).
Air O2
IIB1a(2) inlet
Inlet
158. B. Servo-controlled humidifiers incorporate a temper- Bypass outlet
to proportioning Alarm reed
ature-sensing probe to monitor the temperature in the module outlet
tubing. The sensing probe then signals the heater sys-
tem in terms of the amount of heat that needs to be Figure 4-18: Functional components of an alarm module of
a Sechrist air-oxygen blender.
added to the therapeutic gas to achieve the desired
temperature. When the gas flow through the system is As gas flows through the small hole covered with the
extremely low, the temperature sensing probe might reed, a high-pitched sound develops—alerting person-
remain cool. Changing to continuous-flow CPAP or nel to this situation.
shortening the tubing might correct this situation. Us-
(5:45), (13:69–70).
ing a heated wire circuit should also help.

266 Chapter 4: Equipment

IIB1f(1) trogen analyzer is established when the analyzer is ex-
160. C. Oropharyngeal airways are contraindicated in con- posed to low gas (0% N2). The slope of the nitrogen
scious or semiconscious patients, because these air- analyzer is determined when the analyzer comes in
ways can provoke the gag reflex, vomiting, or contact with the high gas (80% N2). Both the balance
laryngospasm. When it is apparent that the oropharyn- and slope are achieved when adjustments are made to
geal airway will not be tolerated, then the nasopharyn- the analyzer as the analyzer’s sensor is sampling the
geal airway needs to be inserted. test gases. The balance and slope determinations are
performed separately.
(1:647–648), (5:239–240), (13:158), (16:565–567).
To establish linearity for any instrument, multiple
(three or more), different test signals need to be used.
IIB1h(2)
The instrument must be challenged by multiple test
161. D. The delivered oxygen concentration from an oxy- signals for linearity to be established. Therefore,
gen concentrator normally decreases as the oxygen merely correctly balancing and sloping (two-point cal-
flow rate from the concentrator is increased. For ex- ibration) an instrument does not ensure linearity.
ample, oxygen flow rates of 1 to 2 liters/min. deliver
an FIO2 range of 0.94 to 0.97. When the flow-meter (1:373), (6:304–305), (11:386–389).
setting increases to between 3 and 5 liters/min., the
FIO2 falls to between 0.83 and 0.93. IIB1f(3)
(1:1115), (5:17–18, 22), (13:44), (16:896). 165. C. Some tracheostomy tubes are designed with a re-
movable inner cannula, which enables cleaning while
the outer cannula maintains airway patency. Therefore,
IIB2i(1) the outer cannula should be left in place as the inner
162. D. IPPB machines are pressure-cycled ventilators. The cannula is cleaned. The other choices that were avail-
inspiratory phase will end when the pressure-sensing able would not maintain airway patency.
mechanism of the ventilator achieves a preset value. A
closed circuit is needed to achieve this preset pressure. (1:594), (5:246–247), (13:172–173), (16:580–582).
When a circuit disconnection occurs, the circuit is no
longer a closed system. Therefore, the preset pressure IIB1h(1)
will not be achieved if the nebulizer line becomes dis- 166. B. High-flow oxygen blenders are precision metering
connected during an IPPB treatment, and the device devices that blend air and oxygen to provide a specific
will not cycle off. FIO2 at flows between 80 and 100 liters/minute. Be-
cause line pressures within a hospital are usually not
(1:782), (16:533).
equal, blenders have an internal pressure regulator that
compensates for slight differences in line pressure. To
IIB2h(1) increase the FIO2, the CRT should merely turn the
163. C. Air-oxygen blenders, or proportioners, are gener- blender knob to increase the oxygen supply, which si-
ally reliable and trouble-free oxygen-delivery appli- multaneously decreases the air supply. The converse of
ances. Occasionally, however, they break down. this statement is also true.
Whenever air-oxygen blenders malfunction, the prob-
lem is usually a leak at some connection. The sources Unfortunately, the blender can be “fooled” if large
of potential leaks are (1) between the gas source (air or variations in line pressure exist. If oxygen pressure
oxygen) and the high-pressure hose, (2) between the greatly exceeds air pressure, the FIO2 will increase. If
high-pressure hoses and the blender, and (3) between air pressure greatly exceeds oxygen pressure, the FIO2
the blender and the oxygen appliance. will decrease. Most manufacturers have incorporated
an alarm into their blenders to sense variations in line
If a difference of 0.02 (2% oxygen concentration) pressure. These variations in line pressure will typi-
or greater exists between the FIO2 set on the blender cally divert gas across a reed, causing an audible whis-
and the readout of the oxygen analyzer, the oxygen an- tle.
alyzer must be calibrated, and the FIO2 of the blender
must be re-analyzed. (1:758–759), (5:43–45), (13:81–84), (16:361,
363–365).
(5:43–45), (13:69–71).
IIB2e(1)
IIB3a 167. B. When an external gas flow is provided, as is the
164. B. The following diagram demonstrates the response case here with a small-volume nebulizer, the patient
of a nitrogen analyzer to calibration (test) gases con- might not be able to trigger the ventilator because she
taining 0% and 80% nitrogen. The balance of the ni- cannot generate enough negative pressure with this

Chapter 4: Equipment 267

 constant flow (from the flow meter operating the neb- the lung analog is calculated. To determine the volume
ulizer) in the circuit. Switching the nebulizer to the of the metal wool, multiply the weight of the metal
ventilator’s integral nebulizer power will eliminate this wool by its density. A person is seated in the body box,
problem. Also, by powering the nebulizer with the and the isothermal lung analog is connected to the
same gas source that is used for the ventilator, the CRT mouthpiece. The shutter closes. The person who is in
avoids any alterations in the FIO2. the body box is instructed to hold his breath and
squeeze the bulb. The Pmouth/Pbox tangent is recorded.
(5:459), (13:635–636), (15:1015–1017).
The thoracic gas volume (VTG) is calculated without
subtracting the PH2O. The VTG determined must be
IIB2h(4) ± 5% of the isothermal lung analog volume.
168. B. In the situation presented here, an error in technique
or sampling is occurring. Based on the consistently high Ten body box measurements of the VTG and Raw by
PaO2 values, the samples are being exposed to oxygen using normal, non-smoking subjects (biologic con-
tensions greater than those for normal arterial PO2 val- trols) must be performed. A daily variation of < 10%
ues. Air bubbles from the atmosphere contain a partial among subjects is common.
pressure of oxygen of approximately 150 mm Hg. Thus, Body box data can be compared with results from the
when exposed to any sample with a PaO2 of less than at- gas-dilution techniques, i.e., seven-minute N2 washout
mospheric PO2, the air will consistently and falsely ele- and He dilution. The VTG can be compared with the
vate the dissolved oxygen tension of the blood sample. FRC from these tests.
The likelihood is that air bubbles are being introduced
into the samples described in this question. (6:307–309), (11:385–387).

(4:27–28), (16:269). IIB2b

170. A. Under normal operation, a wick humidifier is capa-
IIB3b ble of delivering 100% relative humidity at 37ºC at
169. D. An isothermal lung analog (Figure 4-19) is com- flow rates as high as 60 liters/min. If the humidity out-
posed of a 4- to 5-liter glass container holding copper, put is low, a number of factors can be at fault. The
or steel, wool. A two-hole rubber stopper with a fitting float, which helps maintain a constant water level in-
connects with the mouth shutter, and tubing is attached side the humidifier, might be defective. A problem
to a 100-ml rubber bulb. might exist in the reservoir feed system. The reservoir
By subtracting the volume of the copper or steel wool bag or bottle might be empty. Because the humidity
from the volume of the glass container, the volume of output of a wick system depends heavily on a heating
system, the electrical components must also be in-
spected—especially the system’s power source. The
probe wire must also be evaluated, although it senses
the gas temperature at the proximal airway. The unit’s
temperature is regulated by the temperature feedback
from the probe.

Mouthpiece / Shutter (5:110–112), (13:119, 121).

Rubber Squeeze Bulb
Connection Adaptor
IIB1h(4)
Metal Wool 171. A. A transcutaneous oxygen electrode incorporates a
Material heating element (42ºC to 45ºC) to raise the tempera-
ture of the skin and the layers below the surface to in-
Glass crease local perfusion. The heating is also believed to
Erlenmeyer- improve oxygen diffusion across the skin.
Type Flask
The transcutaneous PO2 electrode depends heavily on
the state of perfusion for its accuracy and reliability.
Therefore, in conditions where the perfusion status is
compromised, the utility of the transcutaneous PO2
electrode diminishes. Hypoperfusion of the skin,
caused by hemorrhage, congestive heart failure, septic
shock, hypothermia, or certain medications can cause
Figure 4-19: Glass flask filled with steel or copper wool,
the PtcO2 to be low (usually lower than the actual
used for performing quality control of a body plethysmograph. PaO2).

268 Chapter 4: Equipment

 Transcutaneous PaO2 monitoring is more widely used HIGH PO2
clinically with neonates and infants than with adults
PO2 = 0.2 (760 torr  47 torr)
because of the difference in skin thickness.
= 0.2 (713 torr)
(1:353–355), (5:293), (10:102–105), (13:188–189).
= 142 torr
IIB2h(4) When performing two-point calibration, CRTs often
172. D. The following actions should be taken to address assume that measurements between these two points
the problem of no SpO2 and no pulse-rate readout from are accurate. Each point (high point and low point) it-
a pulse oximeter: self might be accurate; however, the accuracy of the
• Examine to determine whether the probe is too tight points in between might be questionable, especially if
or misaligned. a large difference exists between the high and low val-
—If so, reposition and correctly apply the probe. ues. In other words, linearity does not always exist be-
tween the high and low calibration points.
• Determine whether the ambient light is too strong.
—If so, cover the probe with opaque material Therefore, a two-point calibration using a more narrow
(e.g., a towel or bed sheet). range can be performed. A calibration range that en-
compasses frequently encountered hypoxemic states is
• Assess the perfusion state of the site. gases that have a concentration of 0% to 12% oxygen.
—If so, massage the site for about 30 seconds if These concentrations represent PO2s of the following:
necessary.
LOW CALIBRATION POINT
• Notice whether the patient is moving excessively.
—If so, attempt to calm the patient or select an- PO2 = 0.00 (760 torr  47 torr)
other site. = 0 torr
(1:360–362), (5:298–300, 306), (10:95–98), HIGH CALIBRATION POINT
(13:191–195), (16:275, 310–312).
PO2 = 0.12 (760 torr  47 torr)
IIB3a
= 85 torr
173. D. Electrochemical electrodes, used in blood-gas
analyzers, generally do not provide accurate measure- Calibration gases that have 0% and 12% oxygen rep-
ments over a wide range of values. Therefore, two- resent a more narrow PO2 range and increase the like-
point calibration, which involves calibrating a high lihood of linearity between the PO2 values of 0 torr and
(slope) and a low (balance) value, is performed to try 85 torr. Because most pathologic PO2 values are below
to establish linearity within the range of the two val- 80 torr, the likelihood of accuracy within the patho-
ues. Recall that linearity demands multiple calibration logic range is increased.
points between a high and low range.
(6:309–310), (11:400–401).
Quite often, the PO2 electrode of a blood-gas analyzer is
calibrated within the two points of 0% and 20% oxygen. IIB2a(2)
The calibration gases are bubbled through water at 37ºC. 174. D. Jet nebulizers often deliver FIO2s that are slightly
This process is followed to saturate each gas with water higher than the FIO2 set at the air entrainment port.
vapor (PH2O) at body temperature. The partial pressure When the device is placed on a patient, resistance de-
of each calibration gas depends on the barometric pres- velops through the system and reduces the amount of
sure (PB). The following formula is used to calculate the room air entrained at the nebulizer. Back pressure re-
PO2 of the gas (i.e., the fractional concentration of the sulting from resistance through the delivery circuit re-
gas is multiplied by the corrected barometric pressure), duces the efficiency of the air-entrainment port.
which is PB minus PH2O. The PH2O is the water vapor
capacity at 37ºC, which is 47 torr. Hence, Another factor that increases the resistance to gas flow
through the delivery system includes adding more
PO2 = Fgas  (PB  47 torr) lengths of aerosol tubing to the delivery system. Tub-
So, a two-point calibration using gases of 0% and 20% ing length and resistance to flow are directly related.
oxygen are equivalent to 0 torr and 142 torr PO2, re- As the tubing length increases, the airflow resistance
spectively. increases (and vice-versa). Also, if condensate builds
up in the aerosol tubing, resistance to airflow in-
LOW PO2 creases, thereby reducing the efficiency of the air-
PO2 = 0.00 (760 torr  47 torr) entrainment port and increasing the delivered FIO2.
= 0 torr (1:752–757), (7:422–424), (16:391–394).

Chapter 4: Equipment 269

IIB1n IIB1h(2)
175. C. To ascertain whether the bellows of a bellows-type 179. B. A diaphragm compressor is specifically designed
spirometer are leaking or not, the CRT can inflate the for powering equipment that does not require unre-
bellows with air, close the openings (inspiration/expi- stricted flows at 50 psig. Examples include the Air
ration port), and secure a weight to the bellows. The Shields Diapump, DeVilbiss small nebulizer compres-
weight attached to the bellows pressurizes the air in- sor, and the unit used by Bird to power the Portabird.
side the bellows. If a leak exists, the bellows will lose This type of compressor is ideal for powering small
volume under the weight. If the bellows do not leak, nebulizers. An ideal compressor system used in a hos-
the volume in the bellows will remain constant. pital should have the capacity to maintain a pressure of
50 psig at flow rates as high as 100 liters/minute for all
Using biologic controls or a calibration syringe will
equipment being used.
merely indicate low volumes (depending on the size of
the leak and the rate at which the gas leaves the bel- A typical, portable compressor is used to power a
lows). Low volumes can arise from a leak in the tubing ventilator and dries the air before the air reaches the
system, a poor seal around the mouthpiece, etc. ventilator. If the flow demand from the attached equip-
Lower-than-expected volumes do not necessarily im- ment exceeds the capability of the compressor, “wet
plicate the bellows. air” might be delivered to the equipment causing dam-
age. Some compressors have a low-pressure audible
(6:250–252, 303), (11:7–8).
alarm, as well as a gauge alerting the CRT to this situ-
ation. Water traps should be used on all equipment
IIB1f(4) powered by a compressor.
176. A. The larynx of a neonate is anterior in location com- (5:13–17).
pared to the larynx of an adult. The MacIntosh blade,
by lifting the vallecula, moves the larynx more anteri- IIB3a
orly. The Miller blade facilitates visualization by di-
180. C. A helium analyzer is a thermal conductivity ana-
rectly lifting the epiglottis and causing minimal
lyzer and incorporates a Wheatstone bridge. The
movement of the larynx.
Wheatstone bridge measures the potential difference
(Guidelines for Cardiopulmonary Resuscitation and between current flowing through a sample chamber
Emergency Cardiac Care, Journal of the American and through a reference chamber. The higher the he-
Medical Association (JAMA), October 1992, Vol. 268, lium concentration in the sample chamber, the lower
No. 16, pp. 2277–2278), (15:1126–1127). the electrical resistance through that circuit; hence, a
greater current flowing through that circuit. Figure
IIB1i(1) 4-20 depicts a Wheatstone bridge.
177. A. In the Siemens Servo 900C ventilator, a pressure
Atmospheric
transducer is located in the inspiratory channel after
gas
the inspiratory valve. The transducer constantly mea-
sures pressure variations (airway pressure) in the in- B Atmospheric
spiratory system. Therefore, a disconnection or a gas
loosely fitted connection between the inspiratory R1 R2
channel and the pressure transducer will result in no
airway pressure reading.
A C
(Siemens Servo 900C operating manual).

IIB2f(2) R4 R3
178. A. The maximum recommended cuff pressure is 20 to I
D
25 mm Hg, or 27 to 33 cm H2O. In a recently intubated Gas Gas
patient, cuff pressures this high (30 cm H2O) are usu- sample sample
ally not needed unless the endotracheal tube is too
small. If the tube is too small, the cuff will not make Figure 4-20: Schematic representation of a Wheatstone
contact with the trachea until the cuff pressures are at bridge incorporated with a helium-gas analyzer.
or in excess of the recommended maximum pressures. Gas analyzers must be calibrated under the same condi-
The X-ray also verifies that the tube is too small. A tions encountered during use. Therefore, when calibrat-
larger-size endotracheal tube is indicated. ing a helium analyzer, the water vapor absorber and the
(15:836). CO2 absorber must be connected to enable the passage

270 Chapter 4: Equipment

 of the sample gases. A two-point calibration must be
performed. Because room air contains essentially zero
percent (0%) helium, it can be used for the low calibra-
tion gas to “zero” the analyzer. Because the closed cir-
cuit, helium-dilution FRC determination tests use 10%
helium, 10% helium can be used as the high-calibration
gases. Therefore, a narrow range for helium concentra-
tion is used when calibrating a helium analyzer.
(6:266–267), (11:73–74, 387–390).

IIB2h(1)
181. A. The pulse-dose oxygen-delivery device substitutes
for a flow meter during oxygen therapy and is intended
to conserve the use of oxygen. The device can operate
in two modes: pulse or continuous. During the pulse
mode, a flow sensor detects patient effort. A solenoid
valve then opens, enabling a pulsed dose of oxygen to
be delivered at a preset flow rate. The device does not
provide oxygen flow during exhalation when operat-
ing in the pulse mode. The continuous flow mode de-
livers oxygen at a selected flow rate throughout the
entire ventilatory cycle.
The pulse-dose oxygen-delivery device is designed to be
Figure 4-21: (A) Proper placement of the pulse oximeter
used with only a nasal cannula, a reservoir cannula, or a probe to the patient’s finger. (B) Incorrect application of the
transtracheal oxygen catheter. A simple mask requires pulse oximeter to the patient’s finger.
humidification and a liter flow of at least 5 liters/min. A
pulse-dose oxygen-delivery device cannot accommodate must be examined for malfunctions. For the compressor
a humidifier, which must be used with a simple mask. to function properly, it must be connected to a 115-volt
AC electrical outlet, all connections must be secured,
The CRT needs to place a cannula on this patient so
and the inlet filter must be free of obstructions. There-
that the oxygen delivery can occur. Then, he should
fore, the compressor inlet filter is severely obstructed.
check the patient’s chart to verify the nature of the or-
(5:13–17).
der and who initiated the order. The physician should
then be consulted to clarify and specify the order.
IIB1h(4)
(5:58–70), (13:61–62). 184. C. When measuring the arterial oxygen saturation with
a pulse oximeter, the two LEDs and the photodetector
IIB2h(4) (photodiode) must align. The capillary bed must be sit-
182. D. Figure 4-21 compares the proper application of the uated between these two components of the finger
finger probe of a pulse oximeter to the improper posi- probe. Otherwise, either a poor-quality signal will re-
tion. sult or no signal at all will be produced.
Note that the tip of the finger in the lower half of the If the situation described in this question ever occurs
diagram has been inserted too far into the probe. The (which is rather unlikely), a different style probe needs
tip of any finger that is inserted into a finger probe to be obtained, and/or an alternate monitoring site
must have the patient’s nail aligned with the LEDs and should be used. Figure 4-22 illustrates various styles of
the photodetector to obtain an SpO2 reading. Mis- pulse-oximeter sensors available.
alignment of the LEDs and the photodetector can
Pulse-oximeter sensors can be positioned on sites
cause a weakened signal or no signal at all.
other than the fingers (i.e., the toes, nose, or ears).
(1:360–361), (5:298–300), (10:96–98), (13:191–195)
Applying the probe or sensor too tightly to the moni-
toring site can interfere with local blood flow. Low
IIB1i(1)
perfusion through the site can produce an inadequate
183. B. Based on the information provided, insufficient signal and unpredictable results.
source-gas pressure is being generated from the air com-
pressor. The Bird Mark VII requires 50 psig of source- (1:360–362), (5:298–300), (13:191–195), (16:275,
gas pressure to power the unit. Thus, the compressor r 310–312).

Chapter 4: Equipment 271

 Both a high (10% He) and a low (0% He) helium test
gas were used during the calibration process. A low-
calibration gas establishes the “zero point” for the in-
strument. Achieving a zero point means the device is
in balance. The zero point does not necessarily have
to equal zero; rather, it merely represents the low-
calibration value.
The instrument has a correctly established slope,
because the high gas value (test signal) equals the mea-
sured value. Linearity has been achieved by perform-
ing multiple-point (three or more) calibration checks
within the high and low gas range. A two-point cali-
Figure 4-22 bration does not establish linearity. Linearity can only
be assumed following two-point calibration. The like-
IIB2h(1) lihood of linearity increases as the difference between
185. C. When a cylinder valve is turned on, gas flows form the high and the low gas narrows (decreases) in two-
the cylinder into the regulator (reducing valve and flow point calibration. Only multiple-point test signals es-
meter). The cylinder pressure should register, and the tablish linearity. The dotted line in the figure connects
Bourdon gauge flow meter should register zero flow. the multiple test signals used within the calibration
At the same time, there should be no sound coming range (0% to 10% He). The heavy line signifies the ex-
from the cylinder-regulator connection or from the pected value for each point between the high and low
regulator oxygen-delivery device connection. If a hiss- gas points.
ing sound becomes audible, there is a leak in the sys- A random error represents an isolated measurement
tem. A soap solution needs to be applied to all of the falling beyond the control limits. A random error falls
connections for the CRT note the presence of bub- beyond 2 standard deviations (SDs) from the mean.
bling, hence the site of the leak. When the leak is lo- A single random is generally ignored, because it usu-
cated, the connection there must be tightened. ally is of no consequence.
(5:73–74, 387–390), (13:52–56). (4:48), (6:304–305, 311), (11:393–395).

IIB3a IIB1i(2)
186. B. The graph in Figure 4-23 represents calibration data 187. D. Although the pressure manometer corresponds with
for a helium-gas analyzer. the amount of PEEP indicated on the weighted-ball as-
sembly, the weighted-ball threshold resistor is gravity-
He Analyzer dependent and must be placed in a vertical orientation.
10%
A PEEP of 5 cm H2O is registering on the pressure
manometer, because the weighted ball is still seated in
its proper position. Any movement of the patient or of
Measured Value

8%
the ventilator tubing, however, might cause the ball in
the PEEP assembly to roll away from the exhaled flow,
6% thereby either eliminating or reducing the PEEP.
As long as the flow resistor can be maintained verti-
cally, using a water-column device (gravity dependent)
4% instead of the weighted ball is unnecessary. If the situ-
ation prohibits placing the gravity-dependent flow re-
sistor in an upright position, a nongravity-dependent
2%
(spring-loaded) device can be used.
(5:356), (15:911–914), (16:537).

2% 4% 6% 8% 10%
IIB2f(2)
Test Signal Value
188. A. Because the pilot balloon has air in it, the cuff is
Theoretical Equal Value Point
still functioning properly. The ET tube has not been
Connected Points of Actual Measured Values
advanced far enough, however, because the 20-cm
Figure 4-23: Graph illustrating data points between the mark on the tube is visible. For adult males, the ET
high (10%) and low (0%) helium test gases on a helium-gas
analyzer. tube should be advanced until the 21- or 23-cm mark

272 Chapter 4: Equipment

 on the tube is at the level of the patient’s incisors. For As more gas enters the regulator, the flow rate through
females, the distance is a little less, i.e., 19 to 21 cm. the outlet increases. At the same time, pressure within
the regulator increases. The fixed orifice leading to
The likelihood is that the cuff is at the vocal cords and
the Bourdon gauge experiences that increased pres-
cannot maintain a proper seal. Deflating the cuff and
sure. The hollow, coiled tube of the Bourdon gauge
advancing the tube will return it to its proper position.
stretches (attempts to straighten). This extending or
A chest X-ray or fiberoptic bronchoscopy should then
expanding of the hollow, coiled tube moves a pointer
be ordered by a physician to confirm proper tube posi-
attached to the hollow, coiled tube by way of a gear
tioning after the CRT has retaped the tube.
mechanism. If the pressure continues to increase in
(1:597), (16:575). the regulator, the hollow, coiled tube stretches farther.
Essentially, back pressure or resistance to outflow
IIB2h(1) from the opening of the regulator imposes greater
189. B. Air-oxygen blenders consist of (1) pressure regulat- pressure to the inside of the regulator and to the Bour-
ing valves to equalize air and oxygen inlet pressures, don gauge mechanism. Consequently, the Bourdon
(2) a proportioning valve to mix the gases, and (3) an gauge flow meter will indicate a flow rate greater than
audible alarm. The proportioning valve, or precision what is actually being delivered.
metering device, mixes the air and oxygen. By varying (1:731), (5:46), (13:52–53, 55), (16:357, 359).
the size of the air and oxygen inlets, oxygen concen-
trations of 21% to 100% can be achieved with flow IIB3a
rates ranging from 2 to 100 liters/minute. With the use
191. A. When a gas analyzer undergoes a two-point cali-
of a nebulizer, the flow capabilities are limited by the
bration, the balance and slope of the instrumentation
restricted orifice of the nebulizer and the need to set
are qualities being sought. A two-point calibration uses
the nebulizer on the 100% source-gas setting. Simple
a high test gas and a low-calibration gas. When the low
bubble or diffusion humidifiers also restrict the flow
test signal becomes the measured value, the balance of
and lose efficiency at higher flow rates. Using a
the device is established. When the high test signal be-
blender with nebulizers or humidifiers will result in in-
comes the measured value, the slope of the instrument
adequate humidification for the patient.
is established. In the graph depicting the calibration of
Air-oxygen blenders deliver precise oxygen concen- a nitrogen analyzer (Figure 4-25), the slope has not
trations suitable for a variety of devices, including been correctly determined, because the high test signal
oxyhoods. was 80 and the measured value was 60.
(1:835–836), (16:363–364).
Measured Value

IIB1h(1)
190. B. A Bourdon gauge flow meter is found along with a
Bourdon pressure gauge on an adjustable regulator. A
Bourdon gauge incorporates a fixed orifice. The inter-
nal mechanism of a Bourdon gauge flow meter con- 60
nected to an adjustable pressure regulator is shown in
Figure 4-24.

0
80
Test Signal Value
Figure 4-25: Graph illustrating high (80%) and low (0%) ni-
trogen gas calibration points.

The balance has not been achieved here, because the

low test signal value of 0 is being read (measured
value) as 30. Linearity has not been determined, be-
cause multiple (three or more) calibration points have
not been used. A two-point calibration was performed
Figure 4-24: Internal representation of a Bourdon gauge
that is incorporated into an adjustable regulator.

Chapter 4: Equipment 273

(high and low test-gas signal). Two-point calibrations do not aerosol collar to the air-entrainment port, enabling
assure linearity. aerosol to enter the gas flow that the patients breathe.
Note the setup in Figure 4-26.
(6:304–305), (11:393–395).

IIB2a(1)
192. D. During patient exhalation, the reservoir bag on a
partial rebreathing mask should completely fill. If the
bag does not do so, the following causes might apply:
(1) the bag could have a leak, (2) the oxygen flow rate
might be insufficient (6–10 liters/min. operating Aerosol
range), or (3) the tubing could be kinked or obstructed. Entrainment
Collar
In this situation, the oxygen flow rate (10 liters/min.) is
adequate. The fit of the mask against the patient’s face
influences the filling of the reservoir bag. The partial
rebreathing mask does not contain one-way valves.
(1:749–751), (7:414–417), (16:387–389). To
Nebulizer
IIB1p Figure 4-26: Air-entrainment mask with humidification
adaptor attached around the air-entrainment port.
193. D. To determine whether a Heimlich valve (a one-way
valve apparatus) has an ongoing leak, place the valve This patient might benefit from the aerosol therapy.
connected to the chest (thoracostomy) tube under wa- The desired effect is thinning of the patient’s secre-
ter. If air bubbles emerge during lung expansion, an air tions, facilitating their removal.
leak is present. The Heimlich valve prevents the back-
flow of air into the thorax (intrapleural space). Either a Switching to an aerosol mask at 60% would not likely
Heimlich valve or an underwater seal can be used to be helpful, because aerosol output decreases as the
prevent the back-flow of atmospheric air into the in- FIO2 of a jet nebulizer increases. Also, switching to an
trapleural space. aerosol mask set at 35% oxygen might not provide the
patient with a precise FIO2, because an aerosol mask is
(1:486–487), (15:1092–1094). not a fixed-performance oxygen-delivery device. En-
dotracheal suctioning would not be a benefit in the
IIB2h(1) long term. Also, the patient appears to be able to clear
194. D. An uncompensated Thorpe tube flow meter will his own secretions. Increasing the oxygen concentra-
register a zero flow rate if the flow meter is not turned tion does not improve secretion removal.
on or if an obstruction to the gas flow has developed in (1:754–755), (7:417–422), (16:390–391).
the outflow system. In an uncompensated Thorpe tube
flow meter, back pressure created in the gas outflow IIB3b
system causes the flow indicator (metal ball) to fall. If
the obstruction is severe enough and if the back pres- 196. C. A recorder time sweep of a volume-displacement
sure becomes substantial, the flow indicator might fall spirometer can be checked by using a stop watch. For
to zero liters/min. example, some water-sealed spirometers have a kymo-
graph speed that can vary, i.e., 32 mm/min., 150
The CRT needs to check the system for kinked tubing mm/min., and 1,920 mm/min. These distances in mil-
or for gas outflow blockage in the system. The cylinder limeters can be measured with a stopwatch as the ky-
valve in this situation is open, because the Bourdon mograph rotates for one minute. The accuracy of the
gauge registers a pressure of 2,000 psig. recorder time sweep should be checked at least every
(5:47, 49), (13:53–55). three months.
(6:303–304), (11:379–380).
IIB1a(2)
195. D. If needed, humidification can be added to an air en- IIB2o
trainment mask (Venturi mask) set up. Ordinarily, this 197. A. The momentary cessation of suction to any pleural
device operates without supplemental humidification, drainage system causes the water level to fluctuate in
because large flow rates of room air are entrained— the water-seal bottle in synchrony with the respiratory
providing the airway with sufficient water content. At cycle. This response indicates that the chest tube is
times, however, certain patients will require additional patent and is operating normally. If, on the other hand,
humidification. This need can be met by attaching the

274 Chapter 4: Equipment

 the water level in the water-seal bottle does not fluctu- IIB1a(1)
ate with the patient’s respiratory cycle when suction is 200. D. A disposable nonrebreathing mask is a variable per-
momentarily stopped, the chest tube is obstructed and formance, or low-flow, oxygen-delivery device. This
needs to be replaced. oxygen-delivery system differs from a partial rebreath-
(1:486–487), (15:1092–1094). ing device in that the nonrebreathing mask contains a
one-way valve in the face mask itself and a one-way
valve between the mask and the reservoir bag. The pur-
IIB3a pose of the one-way valve in the mask is to decrease the
198. B. When applying commercially prepared quality con- amount of room air entrained by the patient’s inspira-
trols to a blood-gas analyzer, an out-of-control condi- tory effort. The one-way valve between the mask and
tion is referred to as data falling outside of 2 SDs. the reservoir bag prevents any of the patient’s expirate
Regarding the electrodes presented here, the O2 and from entering the reservoir bag and from being re-
CO2 electrodes (despite variability within the 2 S.D. breathed during the ensuing inspiration. Both of these
range as in control. The pH electrode has been consis- valves work to increase the FIO2 of the device.
tently falling outside the 2 S.D. limit. The pH elec-
This device is suitable for patients who require high
trode is out-of-control, although the runs display little
FIO2s, while maintaining a stable ventilatory pattern.
variability.
If the patient’s inspiratory flow demands increase, the
Out-of-control is also defined as 10 consecutive mea- source-gas liter flow must likewise increase.
surements having values either greater than or less
(1:749–750), (5:71–72), (7:414–416), (13:63–64),
than the mean, despite all the values falling within 2
(16:387–388).
S.D. from the mean.
(1:350–352), (6:311–314), (11:402–408). IIB2c
201. B. The FIO2 of an aerosol device will increase when-
IIB1m ever the amount of room air entrained in proportion to
the source-gas flow decreases. Increasing the length of
199. B. Aneroid manometers, many of which are modified
the aerosol-delivery tubing increases the resistance to
Bourdon gauges, have many applications in clinical
gas flow through the circuit. Consequently, less room
practice. Aneroid manometers are used, for example,
air is entrained at the air-entrainment port, and the
to measure endotracheal tube cuff pressures, maxi-
FIO2 increases.
mum inspiratory and expiratory pressures (MIP and
MEP), and pressures associated with mechanical ven- The same effect occurs when water condenses in the
tilation (i.e., PIP and PEEP). aerosol tubing. The condensate increases the resistance
to gas flow in the system, causing back pressure to
Aneroid manometers contain coiled, expandable
build toward the air-entrainment port. The result is
material—usually copper or plastic. The expandable
less-entrained room air and an increased FIO2.
material is also hollow. When the hollow, coiled, ex-
pandable material is connected to a pressure source, To circumvent the problem posed by the lengthy
gas under pressure fills the hollow copper or plastic aerosol tubing, two jet nebulizers can be attached in
tube. Under pressure, the expandable tube stretches. tandem.
As it stretches, the gear mechanism to which it is at-
(1:751–757), (13:13–14, 65–69), (16:391–394).
tached causes a pointer to rotate on a calibrated dial.
Frequently, a restrictor (narrowed orifice) is incorpo- IIB2a(1)
rated into these manometers to avoid damage to the 202. D. During normal operation of a partial rebreathing
device when it is exposed to high and/or rapidly mask, the reservoir bag should not collapse during in-
changing pressures. When exposed to rapidly chang- spiration. During inspiration the patient draws 100%
ing pressure conditions, aneroid manometers often oxygen from the reservoir bag and 100% oxygen from
yield peak pressures that are underestimated and base- the source gas flowing through the system. Depending
line pressures that are overestimated. The cause of on the patient’s inspiratory flow rate, a varying amount
these measurements is the damping effect produced by of room air will be inhaled from around where the
the restrictive orifice contained in many of these mask rests against the patient’s face and through the
manometers. When measuring pressures that do not small port holes on the mask itself. As the patient ex-
rapidly fluctuate, these devices are reliable. hales, the first third of the patient’s expirate (anatomic
(1:94), (5:4–5, 234–235), (13:238). dead-space gas containing 100% O2) enters the bag,
and the source gas fills the remainder of the bag.

Chapter 4: Equipment 275

 If the bag does not completely refill during exhalation, These pressures are not equivalent. Note the conver-
the reason could be (1) the bag has a leak, (2) the sions that follow.
source-gas liter flow does not meet the patient’s inspi-
1 atm = 14.7 psig
ratory demands, or (3) a leak exists elsewhere in the
system. 1 atm = 760 torr
Although the oxygen flow rate in this question is 6 Converting 40 torr to psig,
liters/min., which is within the normal operating range
40 torr X psig
for this device, the flow rate might not be meeting the =
patient’s inspiratory flow demands and might need to 760 torr 14.7 psig
be increased. This oxygen appliance usually operates
588 ton-psig = 760 torr (X)
between 6 and 10 liters/min. Partial rebreathing masks
do not contain one-way valves, but nonrebreathing 588 ton-psig
masks do. =X
760 torr
(1:749–751), (7:414–417), (16:387–389).
0.8 psig = X
IIB3b Therefore, 40 torr equals 0.8 psig conversely, and 2
203. B. A spirometer’s frequency of response is the ability psig equals 103.4 torr.
of the spirometer to measure volumes and flow rates Also, depending on the patient’s condition, a humidi-
accurately over a wide range of frequencies, e.g., dur- fier with a nasal cannula operating at 4 liters/min.
ing a maximum voluntary ventilation (MVV) maneu- might not be necessary.
ver. A spirometer’s frequency of response is not
routinely checked. This response is only checked when (1:664), (7:406), (16:382), (17:241–245).
the accuracy of the instrument’s recordings are under
suspicion. IIB2o
206. C. The momentary cessation of suction to any pleural
To evaluate the response frequency of a device, a sinu-
drainage system causes the water level to fluctuate in
soidal pump is used—because it produces a biphasic
the water-seal bottle in synchrony with the respiratory
(sine-wave) signal. This biphasic signal is excellent for
cycle. This response indicates that the chest tube is
checking the response frequency experienced during
patent and is operating normally. If, on the other hand,
inspiration and exhalation. A sinusoidal pump is also
the water level in the water-seal bottle does not fluctu-
used for calibrating body plethysmographs.
ate with the patient’s respiratory cycle when suction is
(6:301, 303), (11:382). momentarily stopped, the chest tube is obstructed and
needs to be replaced.
IIB1p (1:486–487), (15:1092–1094).
204. D. Three- and four-bottle pleural drainage systems can
operate directly from wall suction. The three-bottle IIB3b
system has only one water seal, whereas the four-bot-
207. B. The data shown in this question are acceptable bio-
tle system contains two. One- and two-bottle pleural
logic control data. Biologic control data must be
drainage systems require a regulated suction system to
within 2.0 standard deviations from the mean. The
operate.
two variables evaluated here (FEV1 and FVC) are well
(1:486–487), (15:1092–1094). within this requirement. The SD for the FEV1 is 0.08,
and the SD for the FVC is 0.07. Using biologic con-
IIB2a(1) trols does not preempt the need for other quality-
205. C. Most humidifiers incorporate a pop-off valve that control measures, however. Spirometers, for example,
sounds as it releases pressure that builds up in the sys- can still have their volume and flow rates evaluated via
tem. If, for example, the oxygen tubing becomes a 3-liter syringe.
kinked or obstructed, pressure increases between the (6:301, 302).
gas source and the obstruction. The pop-off valve re-
leases the excess pressure, and in the process produces IIB2a(1)
a whistling sound. Most pop-off valves activate when
208. B. The danger of aspiration exists when a CRT straps
the pressure in the system becomes excessive.
any mask over the nose and mouth of an unconscious
One textbook states that the pressure pop-off activates patient. If the patient vomits, the likelihood of aspirat-
at 2 psig, whereas two other textbooks state 40 torr. ing stomach contents is high. To correct this situation,

276 Chapter 4: Equipment

 the CRT merely needs to unstrap the oxygen mask and C
rest it on the patient’s face. B
100
A simple mask is generally used for patients in emer-
gency situations and for short-term oxygen delivery. A
100 tons
This mask is not to be used for patients who are se-
verely hypoxemic and obtunded, nor is the simple
mask to be used for patients who are in severe respira-
tory distress with a rapid respiratory rate and irregular
breathing pattern.
Switching to a nasal cannula operating at 2 liters/min.
would be inappropriate, as the oxygen concentration Figure 4-27: A pressure transducer (A) can be calibrated
would differ significantly from that provided by the against a mercury manometer (B). If the monitor (C) indi-
cates the pressure (3 torr) that registers on the manome-
simple mask at 7 liters/min. ter, the measurement is acceptable.
(1:745, 749–750), (7:410–414), (16:387–388). A syringe introduces air into the dome while the vent
port is attached to the mercury manometer. Different
IIB1a(1) pressures within the calibration range can be exerted on
the transducer with the syringe. For example, pressures
209. A. The partial rebreathing mask is a variable perfor-
of 200 torr, 150 torr, 100 torr, and 50 torr can be exerted
mance, or low-flow, oxygen-delivery device. There-
to verify that the transducer is calibrated throughout its
fore, when the patient’s inspiratory demands change
operating range of pressure measurements. If the pres-
(e.g., respiratory rate greater than 25 bpm, VT greater
sure readout on the monitor compares well (3 torr)
than 700 ml, and an irregular ventilatory pattern), the
with the pressure indicated on the mercury manometer,
FIO2 delivered by the device also changes. Most low-
the measurement is acceptable. Otherwise, a different
flow oxygen-delivery systems provide a source-gas
pressure transducer must be used.
flow of 15 liters per minute or less. Therefore, because
a normal adult patient’s inspiratory flow is greater than Zeroing the transducer is only one part of the calibra-
15 liters per minute, substantial amounts of room air tion process. Using a normal subject would not verify
will dilute the source gas when the patient inspires. reliability throughout the entire operating range of
The performance of this oxygen-delivery device will pressures to which the transducer is usually exposed.
change as the patient’s ventilatory status changes. The An electric current would not verify the pressure-
partial rebreathing mask contains a reservoir bag con- sensing mechanism.
nected to the mask. Oxygen tubing provides a flow of
(9:324–325), (13:239).
oxygen from a bubble humidifier. The flow rate of the
source gas must be sufficient enough to maintain the
IIB3b
reservoir bag at least half full during inspiration. An
oxygen flow-rate range of 8 to 15 liters/min. can usu- 211. C. Quality control of a body plethysmograph can be
ally maintain the reservoir bag in this state. performed by using any of the following techniques:

(1:749–750), (5:71–72), (7:414–416), (13:63–64), • isothermal lung analog

(16:387–388). • comparisons with gas-dilution volumes
• comparisons with radiologic (ellipsoid-volume
method or planimetry method) volumes
IIB3b • biologic controls
210. C. Pressure transducers can be calibrated by compar- • known resistors
ing their measurements with known pressure values.
An isothermal lung analogy is a 3- to 5-liter glass flask
Known pressure values can be obtained from a mer-
containing metal wool used as a heat sink to prevent tem-
cury column (manometer).
perature variations of gas inside the flask. The flask con-
First, the transducer must be exposed to the atmos- tains a stopper through which two connectors pass. One
phere and must be zeroed. Atmospheric pressure actu- connector is for a rubber squeeze bulb (60 to 100 ml of
ally becomes zero pressure. The transducer can then be volume), and the second connector is for an adaptor—
calibrated, as shown in Figure 4-27, by using a mer- enabling the flask to be attached to the mouthpiece shut-
cury column. ter/transducer assembly of the plethysmograph.

Chapter 4: Equipment 277

 The accuracy of the isothermal lung analog must be measured via chest X-rays to the TLC, which is mea-
2.0%. Its volume is subtracted from the lung analog. sured by the body box) can be used.
While breathholding, a subject sitting inside the body
Using a U-shaped water manometer calibrates the
box squeezes the rubber bulb to simulate panting. The
mouth-pressure transducer on the body plethysmo-
volume-pressure changes produced by the isothermal
graph. A flow transducer is a component of a body
lung analog constitute the test signals.
box. A flow transducer is a pneumotachometer and can
Radiographic estimation of the TLC can also be com- be calibrated by exposing it to a known flow rate or to
pared with the TLC determined via body plethysmog- a volume signal created by a rotameter or by a cali-
raphy. Either the ellipsoid volume method (PA and brated flow meter.
lateral chest X-rays at maximum inspiration) or the
(6:306–309), (11:99–100, 385–387).
planimetry method (correlating lung-surface areas

STOP
You should stop here to evaluate your performance on the 100 questions relating to matrix sections IIB1, IIB2, and
IIB3. Use the Entry-Level Examination Matrix Scoring Form referring to equipment. Be sure to study the matrix
designations, rationales, and information located in the references.

278 Chapter 4: Equipment

 References
1. Scanlan, C., Spearman, C., and Sheldon, R., Egan’s 12. Koff, P., Eitzman, D., and New, J., Neonatal and Pedi-
Fundamentals of Respiratory Care, 7th ed., Mosby- atric Respiratory Care, 2nd ed., Mosby-Year Book,
Year Book, Inc., St. Louis, MO, 1999. Inc., St. Louis, MO, 1993.
2. Kaemarek, R., Mack, C., and Dimas, S., The Essen- 13. Branson, R., Hess, D., and Chatburn, R., Respiratory
tials of Respiratory Care, 3rd ed., Mosby-Year Book, Care Equipment, J. B. Lippincott, Co., Philadelphia,
Inc., St. Louis, MO, 1990. PA, 1995.
3. Shapiro, B., Peruzzi, W., and Kozlowska-Templin, R., 14. Darovic, G., Hemodynamic Monitoring: Invasive and
Clinical Applications of Blood Gases, 5th ed., Mosby- Noninvasive Clinical Application, 2nd ed., W. B. Saun-
Year Book, Inc., St. Louis, MO, 1994. ders Company, Philadelphia, PA, 1995.
4. Malley, W., Clinical Blood Gases: Application and 15. Pierson, D., and Kacmarek, R., Foundations of Respi-
Noninvasive Alternatives, W. B. Saunders Co., ratory Care, Churchill Livingston, Inc., New York, NY,
Philadelphia, PA, 1990. 1992.
5. White, G., Equipment Theory for Respiratory Care, 16. Burton et. al, Respiratory Care: A Guide to Clinical
3rd ed., Delmar Publishers, Inc., Albany, NY, 1999. Practice, 4th ed., Lippincott-Raven Publishers,
6. Ruppel, G., Manual of Pulmonary Function Testing, Philadelphia, PA, 1997.
7th ed., Mosby-Year Book, Inc., St. Louis, MO, 1998. 17. Wojciechowski, W., Respiratory Care Sciences: An In-
7. Barnes, T., Core Textbook of Respiratory Care Prac- tegrated Approach, 3rd ed., Delmar Publishers, Inc.,
tice, 2nd ed., Mosby-Year Book, Inc., St. Louis, MO, Albany, NY, 1999.
1994. 18. Aloan, C., Respiratory Care of the Newborn and
8. Rau, J., Respiratory Care Pharmacology, 5th ed., Child, 2nd ed., Lippincott-Raven Publishers, Philadel-
Mosby-Year Book, Inc., St. Louis, MO, 1998. phia, PA, 1997.
9. Wilkins, R., Sheldon, R., and Krider, S., Clinical As- 19. Dantzker, D., MacIntyre, N., and Bakow, E., Compre-
sessment in Respiratory Care, 3rd ed., Mosby-Year hensive Respiratory Care, W. B. Saunders Company,
Book, Inc., St. Louis, MO, 1995. Philadelphia, PA, 1998.
10. Pilbeam, S., Mechanical Ventilation: Physiological and 20. Farzan, S., and Farzan, D., A Concise Handbook of
Clinical Applications, 3rd ed., Mosby-Year Book, Inc., Respiratory Diseases, 4th ed., Appleton & Lange,
St. Louis, MO, 1998. Stamford, CT, 1997.
11. Madama, V., Pulmonary Function Testing and Car-
diopulmonary Stress Testing, 2nd ed., Delmar Publish-
ers, Inc., Albany, NY, 1998.

Chapter 4: Equipment 279

 CHAPTER 5 THERAPEUTIC PROCEDURES

PURPOSE: This chapter consists of 235 items intended to assess your understanding and comprehension of sub-
ject matter contained in the Therapeutic Procedures portion of the Entry-Level Examination for Certified Respira-
tory Therapists. In this chapter, you will be required to answer questions regarding the following activities:

A. Educating patients; maintaining records and communication; and performing infection control
B. Maintaining an airway and mobilizing and removing secretions
C. Assuring ventilation
D. Assuring oxygenation
E. Assessing patient response
F. Modifying therapy/making recommendations based on the patient’s response
G. Performing emergency resuscitation

Recall from the introduction that the NBRC Entry-Level Examination is divided into three content areas:
I. Clinical Data
II. Equipment
III. Therapeutic Procedures
Table 5-1 indicates the number of questions in the Therapeutic Procedures section and the number of questions ac-
cording to the level of complexity.

Table 5-1

Number of Questions Level of Complexity

Content Area in Content Area Recall Application Analysis

III. Therapeutic
Procedures 79 15 36 28

This chapter is designed to help you work through the 90 NBRC matrix entries pertaining to therapeutic procedures
on the Entry-Level Examination. Keep in mind, however, that many of the 90 matrix entries in this content area en-
compass multiple competencies. For example, Entry-Level Exam Matrix item IIIE1i(1) pertains to modifying me-
chanical ventilation. This matrix item encompasses adjusting ventilation settings, e.g., (1) ventilatory mode, (2) tidal
volume, (3) FIO2, (4) inspiratory plateau, (5) PEEP and CPAP levels, (6) pressure support and pressure-control lev-
els, (7) non-invasive positive pressure, and (8) alarm settings. Notice that matrix item IIIE1i(1) pertains to eight dif-
ferent aspects of modifying mechanical ventilation. Therefore, at least eight different questions can come from this
matrix item. Again, most other matrix items in this section and in the other two sections entail multiple components.
Chapter Five is organized according to the order of the matrix items listed in the NBRC Entry-Level Examination Ma-
trix. First, you will encounter 40 questions relating to the matrix heading IIIA. Matrix heading IIIA expects you to:
IIIA—Explain planned therapy and goals to a patient, maintain records and communication, and pro-
tect a patient from nosocomial infection

280
 Second, you will be challenged with 22 questions concerning matrix heading IIIB. Matrix heading IIIB reads as
follows:
IIIB—Conduct therapeutic procedures to maintain a patent airway and remove bronchopulmonary se-
cretions

In the following section, you will be faced with 25 questions pertaining to matrix heading IIIC. Matrix heading
IIC asks you to:
IIIC—Conduct therapeutic procedures to achieve adequate ventilation and oxygenation

Afterwards, you will be asked to answer 23 questions about matrix heading IIID. Matrix heading IIID expects
you to:
IIID—Evaluate and monitor a patient’s response to respiratory care

Then, you will be confronted with 93 questions having to do with matrix heading IIIE. Matrix heading IIIE ex-
pects you to:
IIIE—Modify and recommend modifications in therapeutics and recommend pharmacologic agents

Next, you will deal with 19 questions relating to matrix heading IIIF. Matrix heading IIIF asks you to:
IIIF—Treat cardiopulmonary collapse according to BLS, ACLS, PALS, and NRP protocols

Finally, you will be expected to answer 13 questions concerning matrix heading IIIG. Matrix heading IIIG
reads as follows:
IIIG—Assist the physician and initiate and conduct pulmonary rehabilitation and home care

Adhering to this sequence will assist you in organizing your personal study plan. Without a plan, your approach
will be haphazard and chaotic. Furthermore, you will waste precious time and effort studying unnecessary and
irrelevant material. Proceeding as outlined here, you will find your strengths and weaknesses in the Therapeutic
Procedures content area.

The following matrix sections within Therapeutic Procedures will be grouped together in this chapter as follows:

1. IIIA, IIIB, IIIC, and IIID

2. IIIE, IIIF, and IIIG

After finishing sections IIIA, IIIB, IIIC, and IIID, stop to evaluate your work by (1) studying the analyses (located
further in this chapter), (2) reading references, and (3) reviewing the relevant NBRC Entry-Level Matrix items. Fol-
lowing this group of matrix sections, you will find the pertinent portion of the Entry-Level Examination Matrix. Be
sure to thoroughly review these matrix items, because they are the basis of the Entry-Level Examination.
When you finish evaluating and studying sections IIIA, IIIB, IIIC, and IIID, proceed to the other group of matrix
sections within Therapeutic Procedures (i.e., IIIE, IIIF, and IIIG). After completing the questions in this section, per-
form the same evaluation process as previously described.
Attempt to complete each group of matrix sections uninterruptedly. Be sure you have sufficient time (1) to answer
the questions, (2) to review the analyses, (3) to use the references as needed, and (4) to thoroughly study the Entry-
Level matrix items.
Table 5-2 indicates each content area within the Therapeutic Procedures section and the number of matrix items
in each section.

Chapter 5: Therapeutic Procedures 281

Table 5-2

Therapeutic Number of Matrix

Procedures Sections Items per Section

IIIA 12
IIIB 9
IIIC 11
IIID 10
IIIE 35
IIIF 4
IIIG 9
TOTAL 90

Table 5-3 outlines each content area within the Therapeutic Procedures section and the number of questions from
each content area on the Entry-Level Examination.

Table 5-3

Number of Questions
Therapeutic from Each Section on
Procedures Sections the Entry-Level Exam

IIIA 5
IIIB 5
IIIC 16
IIID 10
IIIE 32
IIIF 6
IIIG 5
TOTAL 79

Remember, many matrix items have multiple components. Therefore, certain matrix designations will be repeated
but will pertain to different concepts. Make sure you read and study the matrix designations, because the NBRC
Entry-Level Examination is based on the Entry-Level Examination Matrix.
NOTE: Please refer to the examination matrix, located at the end of section IIID (pages 305 and 306). This exami-
nation matrix key will enable you to identify the specific areas on the Entry-Level Examination matrix that require
remediation, based on your performance on the test items in sections IIIA, IIIB, IIIC, and IIID.

Use the answer sheet to record your answers as you work through questions relating to therapeutic procedures.
Remember to study the analyses that follow the questions in this chapter. The purpose of each analysis is to pre-
sent you with the rationale for the correct answer, and in many instances, reasons are given for why the distractors
are incorrect. The references at the end of each analysis provide you with resources to seek more information re-
garding each question and its associated Entry-Level Examination matrix item. The following 110 questions refer
to the Entry-Level Matrix sections IIIA, IIIB, IIIC, and IIID.

282 Chapter 5: Therapeutic Procedures

 Therapeutic Procedures Answer Sheet
DIRECTIONS: Darken the space under the selected answer.

A B C D A B C D
1. ❏ ❏ ❏ ❏ 25. ❏ ❏ ❏ ❏
2. ❏ ❏ ❏ ❏ 26. ❏ ❏ ❏ ❏
3. ❏ ❏ ❏ ❏ 27. ❏ ❏ ❏ ❏
4. ❏ ❏ ❏ ❏ 28. ❏ ❏ ❏ ❏
5. ❏ ❏ ❏ ❏ 29. ❏ ❏ ❏ ❏
6. ❏ ❏ ❏ ❏ 30. ❏ ❏ ❏ ❏
7. ❏ ❏ ❏ ❏ 31. ❏ ❏ ❏ ❏
8. ❏ ❏ ❏ ❏ 32. ❏ ❏ ❏ ❏
9. ❏ ❏ ❏ ❏ 33. ❏ ❏ ❏ ❏
10. ❏ ❏ ❏ ❏ 34. ❏ ❏ ❏ ❏
11. ❏ ❏ ❏ ❏ 35. ❏ ❏ ❏ ❏
12. ❏ ❏ ❏ ❏ 36. ❏ ❏ ❏ ❏
13. ❏ ❏ ❏ ❏ 37. ❏ ❏ ❏ ❏
14. ❏ ❏ ❏ ❏ 38. ❏ ❏ ❏ ❏
15. ❏ ❏ ❏ ❏ 39. ❏ ❏ ❏ ❏
16. ❏ ❏ ❏ ❏ 40. ❏ ❏ ❏ ❏
17. ❏ ❏ ❏ ❏ 41. ❏ ❏ ❏ ❏
18. ❏ ❏ ❏ ❏ 42. ❏ ❏ ❏ ❏
19. ❏ ❏ ❏ ❏ 43. ❏ ❏ ❏ ❏
20. ❏ ❏ ❏ ❏ 44. ❏ ❏ ❏ ❏
21. ❏ ❏ ❏ ❏ 45. ❏ ❏ ❏ ❏
22. ❏ ❏ ❏ ❏ 46. ❏ ❏ ❏ ❏
23. ❏ ❏ ❏ ❏ 47. ❏ ❏ ❏ ❏
24. ❏ ❏ ❏ ❏ 48. ❏ ❏ ❏ ❏

Chapter 5: Therapeutic Procedures 283

 A B C D A B C D
49. ❏ ❏ ❏ ❏ 77. ❏ ❏ ❏ ❏
50. ❏ ❏ ❏ ❏ 78. ❏ ❏ ❏ ❏
51. ❏ ❏ ❏ ❏ 79. ❏ ❏ ❏ ❏
52. ❏ ❏ ❏ ❏ 80. ❏ ❏ ❏ ❏
53. ❏ ❏ ❏ ❏ 81. ❏ ❏ ❏ ❏
54. ❏ ❏ ❏ ❏ 82. ❏ ❏ ❏ ❏
55. ❏ ❏ ❏ ❏ 83. ❏ ❏ ❏ ❏
56. ❏ ❏ ❏ ❏ 84. ❏ ❏ ❏ ❏
57. ❏ ❏ ❏ ❏ 85. ❏ ❏ ❏ ❏
58. ❏ ❏ ❏ ❏ 86. ❏ ❏ ❏ ❏
59. ❏ ❏ ❏ ❏ 87. ❏ ❏ ❏ ❏
60. ❏ ❏ ❏ ❏ 88. ❏ ❏ ❏ ❏
61. ❏ ❏ ❏ ❏ 89. ❏ ❏ ❏ ❏
62. ❏ ❏ ❏ ❏ 90. ❏ ❏ ❏ ❏
63. ❏ ❏ ❏ ❏ 91. ❏ ❏ ❏ ❏
64. ❏ ❏ ❏ ❏ 92. ❏ ❏ ❏ ❏
65. ❏ ❏ ❏ ❏ 93. ❏ ❏ ❏ ❏
66. ❏ ❏ ❏ ❏ 94. ❏ ❏ ❏ ❏
67. ❏ ❏ ❏ ❏ 95. ❏ ❏ ❏ ❏
68. ❏ ❏ ❏ ❏ 96. ❏ ❏ ❏ ❏
69. ❏ ❏ ❏ ❏ 97. ❏ ❏ ❏ ❏
70. ❏ ❏ ❏ ❏ 98. ❏ ❏ ❏ ❏
71. ❏ ❏ ❏ ❏ 99. ❏ ❏ ❏ ❏
72. ❏ ❏ ❏ ❏ 100. ❏ ❏ ❏ ❏
73. ❏ ❏ ❏ ❏ 101. ❏ ❏ ❏ ❏
74. ❏ ❏ ❏ ❏ 102. ❏ ❏ ❏ ❏
75. ❏ ❏ ❏ ❏ 103. ❏ ❏ ❏ ❏
76. ❏ ❏ ❏ ❏ 104. ❏ ❏ ❏ ❏

284 Chapter 5: Therapeutic Procedures

105. ❏ ❏ ❏ ❏ 134. ❏ ❏ ❏ ❏
106. ❏ ❏ ❏ ❏ 135. ❏ ❏ ❏ ❏
107. ❏ ❏ ❏ ❏ 136. ❏ ❏ ❏ ❏
108. ❏ ❏ ❏ ❏ 137. ❏ ❏ ❏ ❏
109. ❏ ❏ ❏ ❏ 138. ❏ ❏ ❏ ❏
110. ❏ ❏ ❏ ❏ 139. ❏ ❏ ❏ ❏
111. ❏ ❏ ❏ ❏ 140. ❏ ❏ ❏ ❏
112. ❏ ❏ ❏ ❏ 141. ❏ ❏ ❏ ❏
113. ❏ ❏ ❏ ❏ 142. ❏ ❏ ❏ ❏
114. ❏ ❏ ❏ ❏ 143. ❏ ❏ ❏ ❏
115. ❏ ❏ ❏ ❏ 144. ❏ ❏ ❏ ❏
116. ❏ ❏ ❏ ❏ 145. ❏ ❏ ❏ ❏
117. ❏ ❏ ❏ ❏ 146. ❏ ❏ ❏ ❏
118. ❏ ❏ ❏ ❏ 147. ❏ ❏ ❏ ❏
119. ❏ ❏ ❏ ❏ 148. ❏ ❏ ❏ ❏
120. ❏ ❏ ❏ ❏ 149. ❏ ❏ ❏ ❏
121. ❏ ❏ ❏ ❏ 150. ❏ ❏ ❏ ❏
122. ❏ ❏ ❏ ❏ 151. ❏ ❏ ❏ ❏
123. ❏ ❏ ❏ ❏ 152. ❏ ❏ ❏ ❏
124. ❏ ❏ ❏ ❏ 153. ❏ ❏ ❏ ❏
125. ❏ ❏ ❏ ❏ 154. ❏ ❏ ❏ ❏
126. ❏ ❏ ❏ ❏ 155. ❏ ❏ ❏ ❏
127. ❏ ❏ ❏ ❏ 156. ❏ ❏ ❏ ❏
128. ❏ ❏ ❏ ❏ 157. ❏ ❏ ❏ ❏
129. ❏ ❏ ❏ ❏ 158. ❏ ❏ ❏ ❏
130. ❏ ❏ ❏ ❏ 159. ❏ ❏ ❏ ❏
131. ❏ ❏ ❏ ❏ 160. ❏ ❏ ❏ ❏
132. ❏ ❏ ❏ ❏ 161. ❏ ❏ ❏ ❏
133. ❏ ❏ ❏ ❏ 162. ❏ ❏ ❏ ❏

Chapter 5: Therapeutic Procedures 285

 A B C D A B C D
163. ❏ ❏ ❏ ❏ 191. ❏ ❏ ❏ ❏
164. ❏ ❏ ❏ ❏ 192. ❏ ❏ ❏ ❏
165. ❏ ❏ ❏ ❏ 193. ❏ ❏ ❏ ❏
166. ❏ ❏ ❏ ❏ 194. ❏ ❏ ❏ ❏
167. ❏ ❏ ❏ ❏ 195. ❏ ❏ ❏ ❏
168. ❏ ❏ ❏ ❏ 196. ❏ ❏ ❏ ❏
169. ❏ ❏ ❏ ❏ 197. ❏ ❏ ❏ ❏
170. ❏ ❏ ❏ ❏ 198. ❏ ❏ ❏ ❏
171. ❏ ❏ ❏ ❏ 199. ❏ ❏ ❏ ❏
172. ❏ ❏ ❏ ❏ 200. ❏ ❏ ❏ ❏
173. ❏ ❏ ❏ ❏ 201. ❏ ❏ ❏ ❏
174. ❏ ❏ ❏ ❏ 202. ❏ ❏ ❏ ❏
175. ❏ ❏ ❏ ❏ 203. ❏ ❏ ❏ ❏
176. ❏ ❏ ❏ ❏ 204. ❏ ❏ ❏ ❏
177. ❏ ❏ ❏ ❏ 205. ❏ ❏ ❏ ❏
178. ❏ ❏ ❏ ❏ 206. ❏ ❏ ❏ ❏
179. ❏ ❏ ❏ ❏ 207. ❏ ❏ ❏ ❏
180. ❏ ❏ ❏ ❏ 208. ❏ ❏ ❏ ❏
181. ❏ ❏ ❏ ❏ 209. ❏ ❏ ❏ ❏
182. ❏ ❏ ❏ ❏ 210. ❏ ❏ ❏ ❏
183. ❏ ❏ ❏ ❏ 211. ❏ ❏ ❏ ❏
184. ❏ ❏ ❏ ❏ 212. ❏ ❏ ❏ ❏
185. ❏ ❏ ❏ ❏ 213. ❏ ❏ ❏ ❏
186. ❏ ❏ ❏ ❏ 214. ❏ ❏ ❏ ❏
187. ❏ ❏ ❏ ❏ 215. ❏ ❏ ❏ ❏
188. ❏ ❏ ❏ ❏ 216. ❏ ❏ ❏ ❏
189. ❏ ❏ ❏ ❏ 217. ❏ ❏ ❏ ❏
190. ❏ ❏ ❏ ❏ 218. ❏ ❏ ❏ ❏

286 Chapter 5: Therapeutic Procedures

219. ❏ ❏ ❏ ❏ 228. ❏ ❏ ❏ ❏
220. ❏ ❏ ❏ ❏ 229. ❏ ❏ ❏ ❏
221. ❏ ❏ ❏ ❏ 230. ❏ ❏ ❏ ❏
222. ❏ ❏ ❏ ❏ 231. ❏ ❏ ❏ ❏
223. ❏ ❏ ❏ ❏ 232. ❏ ❏ ❏ ❏
224. ❏ ❏ ❏ ❏ 233. ❏ ❏ ❏ ❏
225. ❏ ❏ ❏ ❏ 234. ❏ ❏ ❏ ❏
226. ❏ ❏ ❏ ❏ 235. ❏ ❏ ❏ ❏
227. ❏ ❏ ❏ ❏

Chapter 5: Therapeutic Procedures 287

 Therapeutic Procedures Assessment
DIRECTIONS: Each of the questions or incomplete statements below is followed by four suggested answers or
completions. Select the one that is best in each case, then blacken the corresponding space on
the answer sheet found in the front of this chapter. Good luck.

IIIA1 I. Avoid smoking-related activities.

1. How should a CRT instruct a patient who has severe II. Smoke low-nicotine cigarettes when the patient is
pulmonary emphysema to cough? present.
III. Create a calm, low-stress environment at home.
A. The patient should be instructed to take as deep a IV. Help remind the patient to avoid using nicotine gum
breath as possible, and then cough as forcefully as in stressful situations.
possible.
B. The patient should be instructed to place his A. I, III only
hands across his abdomen and compress them in- B. II, IV only
ward as he coughs, following a full inspiration. C. I, III, IV only
C. The patient should be instructed to inhale slightly D. I, II, III, IV
more than a tidal breath and exhale with short,
rapid bursts of air. IIIA1
D. The patient should be instructed to place a pillow 5. An asthmatic patient is about to be discharged from
against his chest as he exhales moderately through the hospital. What information must the CRT give the
pursed lips. patient before the patient leaves the hospital?
I. how to avoid asthma triggers
IIIA1 II. how to use metered-dose inhalers (MDIs)
2. Which of the following factors should be included in III. how to determine which spirometric test is best
documentation of a respiratory-therapy procedure? IV. how to taper oral corticosteroids
I. type of therapy A. I, II only
II. date and time of administration B. III, IV only
III. effects of therapy C. I, II, IV only
IV. adverse effects noted D. I, II, III, IV
A. I, II only
IIIA1
B. I, III only
C. I, II, III only 6. Which of the following information should be dis-
D. I, II, III, IV cussed with patients in a smoking-cessation program?
I. how to help others quit smoking
IIIA1 II. what type of withdrawal symptoms to expect
3. How should a patient who is receiving helium-oxygen III. how the body’s metabolism is affected
therapy be instructed to cough during this procedure? IV. how to modify their own behavior

A. The patient should be instructed to cough from to- A. I, IV only

tal lung capacity. B. II, III only
B. The patient should be instructed to cough from a C. II, III, IV only
volume slightly larger than a tidal volume. D. I, II, III, IV
C. The patient should exhale rapidly through pursed
lips from total lung capacity. IIIA1
D. The patient should breathe a few breaths of room 7. Which of the following responses or levels of conscious-
air before attempting to cough. ness reflect a patient’s ability to follow instructions?
A. orientation to person
IIIA1 B. performance of tasks when asked
4. What are some actions that family members who smoke C. orientation to place
can take to assist a COPD patient to quit smoking? D. orientation to time

288 Chapter 5: Therapeutic Procedures

IIIA1 C. He should chart his actions and defer an interpre-
8. A 60-year-old COPD patient is experiencing dyspnea tation.
at rest. The physician orders a bronchodilator delivered D. He should leave a blank area in the patient’s chart
from an MDI for the patient. As the CRT enters the pa- to be filled in later after consulting a supervisor.
tient’s room to discuss and administer the initial treat-
ment, the patient belligerently demands the CRT to IIIA2a
leave the room and leave behind the MDI. What 12. The CRT has just completed performing postural
should the CRT do at this time? drainage on a patient who has retained secretions.
A. Talk calmly and try to be convincing to the patient. Which of the following aspects of the therapeutic pro-
B. Be assertive and demand that the patient listen cedure need to be included in the patient’s chart?
and comply with the orders. I. the position(s) used
C. Do as the patient requests. II. how long the patient was maintained in each
D. Request the nurse to perform the treatment. position
III. the patient’s fluid-volume intake
IIIA1b(4) IV. discomfort expressed by the patient
9. A COPD patient is receiving a beta-two agonist via a
A. I, II only
small-volume nebulizer. The CRT notes that the pa-
B. III, IV only
tient’s heart rate has increased from 75 beats/minute
C. I, II, IV only
before the treatment to 105 beats/minute during the
D. I, II, III, IV
treatment. What should the CRT do at this time?
A. Switch to a different beta-two agonist. IIIA2b(1)
B. Continue the treatment and monitor the patient. 13. A CRT has been asked to assess the effectiveness of
C. Terminate the treatment and notify the physician. chest physiotherapy being performed TID for the past
D. Have the patient use an MDI instead of the small- two days on a 67-year-old asthmatic patient who is be-
volume nebulizer. ing treated for pneumonia. Auscultation of the lower
lobes reveals diminished breath sounds and rhonchi
IIIA2a over the posterior thorax. What recommendation
10. While recording the results of an aerosolized -2 ago- should the CRT make based on these findings?
nist treatment, the CRT erroneously wrote the trade
A. The therapy has been effective and should now be
name of the wrong -2 agonist. What should she do in
discontinued.
this situation?
B. An aerosolized beta-2 agonist should be added to
A. Leave the trade name written, because it is also the therapy.
classified as a -2 agonist. C. The patient has had an adverse reaction to the
B. Erase the wrong trade name and write in the name therapeutic regimen.
of the correct drug. D. The therapy is ineffective and should be discon-
C. Use correction fluid on the wrong trade name and tinued.
write in the name of the correct medication.
D. Draw a horizontal line through the incorrect trade IIIA2b(1)
name, print the word “error” above it, and con- 14. An asthmatic patient is receiving an aerosolized, beta-
tinue charting. adrenergic bronchodilator. While monitoring the pa-
tient during the treatment, the CRT obtains the
IIIA2a following data:
11. After recently changing a dyspneic COPD patient’s
• heart rate: 125 beats/minute
oxygen-delivery device from a nasal cannula at 5
• blood pressure: 185/115 torr
liters/min to an air entrainment mask delivering an
• ventilatory rate: 30 breaths/minute
FIO2 of 0.40, the CRT is unable to determine the pa-
tient’s response to the change in therapy. What action The patient complains of dizziness and displays
should the CRT take when documenting his actions in tremors. Which of the following action(s) is (are) ap-
the patient’s chart pertaining to this situation? propriate at this time?
A. He should exercise his judgment and make some I. performing an arterial puncture
interpretation. II. terminating the treatment
B. He should address in the chart his inability to eval- III. initiating suctioning
uate the situation and seek input from a supervisor. IV. instructing the patient to take slow, deep breaths

Chapter 5: Therapeutic Procedures 289

 A. II only The following arterial blood-gas data were obtained at
B. I, II only these settings.
C. I, IV only
PO2 55 torr
D. I, II, III only
PCO2 46 torr
pH 7.34
IIIA2b(1)
15. During the administration of an anticholinergic bron- The PEEP study being reviewed by the CRT is as follows:
chodilator treatment, the patient’s blood pressure be-
comes 80/50 torr. His radial pulse is rapid and thready, Table 5-4: PEEP trial performed at FIO2 0.60
and he exhibits respiratory distress. What type of adverse blood heart rate
reaction to the medication does this situation exemplify? PEEP CL C.O. pressure (beats/ PaO2
A. tachyphylaxis (cm H2O) (ml/cm H2O) (L/min.) (torr) minute) (torr)
B. anaphylaxis 0 25 4.20 130/60 115 55
C. idiosyncrasy 5 29 4.90 135/70 111 59
D. toxicity 8 35 5.30 135/75 106 69
10 28 4.80 120/65 112 60
IIIA2b(1)
16. A patient complains of dizziness, sweating, and tin- Based on these findings, what should the CRT recom-
gling of the fingers and toes after every IPPB. Which mend?
of the following causes might be responsible for this
patient’s symptoms? A. Reduce the FIO2 to 0.60.
B. Institute PEEP.
A. The patient was inhaling too deeply or too rapidly. C. Institute pressure-support ventilation.
B. The patient was rebreathing a portion of her ex- D. Institute inverse-ratio ventilation.
haled volume.
C. The sensitivity was set too high. IIIA2b(3)
D. The patient is receiving too high of an FIO2.
19. The CRT is attempting to obtain a sputum sample from
a patient. After coughing vigorously, the patient ex-
IIIA2b(2)
pectorates white, clear, frothy sputum into the speci-
17. The CRT measured a normal patient’s lung volumes men cup. What should the CRT do at this time?
and capacity with a spirometer under normal baromet-
ric conditions at a temperature of 24ºC. The patient’s A. Discard the sample and try again later.
vital capacity was measured to be 5.00 liters and was B. Cap the specimen cup and send it to the lab.
recorded as 5.00 liters. A coworker questioned the C. Keep the specimen cup uncovered until the frothy
value of the vital capacity. What was the basis for material evaporates.
questioning the recorded value? D. Add sterile water to the specimen cup to help
eliminate the froth.
A. The coworker is incorrect for questioning the
recorded value of the vital capacity. IIIA2b(3)
B. The CRT did not report the vital capacity in terms
of the body temperature, pressure, and saturation. 20. The CRT observes immediately after surgery the fol-
C. The CRT should have subtracted the PH2O at lowing clinical signs over the right lower lobe of a
37ºC from the barometric pressure. post-op thoracotomy patient.
D. The CRT should have subtracted the PH2O at 1. decreased tactile fremitus
37ºC from the measured volume. 2. right-sided, reduced chest wall expansion
3. dull percussion notes
IIIA2b(2) 4. decreased breath sounds
18. While reviewing the chart of a mechanically ventilated 5. radiopacity
patient, the CRT notices that a PEEP trial was con-
ducted when the patient was receiving an FIO2 of 0.60 After a day and a half of hyperinflation therapy, the patient
(refer to Table 5-4). The current ventilator settings in- now exhibits the following signs over the same lung area:
clude the following: 1. feeling of vibrations on the chest wall as the patient
• mode: control speaks
• tidal volume: 900 ml 2. bilateral movement of the thumbs from the pa-
• ventilatory rate: 12 breaths/minute tient’s midline by 4 cm
• FIO2: 0.70 3. moderately low-pitched percussion note

290 Chapter 5: Therapeutic Procedures

 4. no adventitious breath sounds gressively decreased while the patient’s SpO2 gradually
5. radiolucency declined from 90% to 75%. The patient was switched
to an air entrainment mask at 24%. Shortly, the pa-
What interpretation should the CRT make based on
tient’s ventilatory rate normalized, and the SpO2 rose to
these findings?
92%. How should the CRT interpret this situation?
A. The patient has developed pulmonary edema.
A. The patient experienced oxygen-induced hypo-
B. The patient’s pneumothorax has been absorbed.
ventilation.
C. The patient’s atelectasis has reversed.
B. The patient had reversal of microatelectasis.
D. The patient’s pneumonia has resolved.
C. The nasal cannula was defective.
D. The nasal cannula was not providing the patient
IIIA2b(4) with enough oxygen.
21. A patient who is receiving mechanical ventilatory sup-
port is being weaned via Briggs adaptor trials. The IIIA2b(5)
physician’s order calls for the initial trials to be 15 24. A COPD patient has been receiving oxygen at home via
minutes each hour. The following data were obtained an oxygen concentrator. The patient’s oxygen-delivery
before the first trial: system was switched to a liquid-oxygen system. The pa-
• heart rate: 80 beats/minute tient was using a nasal cannula at 2 liters/min., with the
• ventilatory rate: 18 breaths/minute concentrator and remains on the same flow rate with a
• FIO2: 0.40 pendant reservoir cannula attached to the liquid-oxygen
• maximum inspiratory pressure: –25 cm H2O system. The patient’s SpO2 on the nasal cannula was
• vital capacity: 10 ml/kg 92%. The SpO2 is now 99% with the pendant nasal can-
• SpO2: 94% nula. What action should the CRT take at this time?
After breathing 10 minutes via the Briggs adaptor, the A. Switch back to the nasal cannula for the liquid-
measurements shown below were obtained. oxygen system.
B. Reduce the flow rate to the pendant nasal cannula
• heart rate: 100 beats/minute to 1 liter/min.
• ventilatory rate: 28 breaths/minute C. Switch from the pendant nasal cannula to a reser-
• FIO2: 0.40 voir cannula.
• maximum inspiratory pressure: –13 cm H2O D. This effect is transitory and will self-correct when
• vital capacity: 7 ml/kg the temperature of the liquid oxygen reaches
• SpO2: 86% room temperature.
What should the CRT do at this time?
IIIA2c
A. Continue with the weaning procedure and monitor
the patient. 25. The CRT is asked to evaluate a patient for possible
B. Reconnect the patient to the mechanical ventilator. therapeutic intervention. Upon performing inspection,
C. Nebulize a bronchodilator in-line with the Briggs the CRT observes a thin patient whose transverse
adaptor. chest-wall diameter appears equal to his anteroposte-
D. Add 50 cc more of reservoir tubing to the distal rior diameter. The CRT also notices paradoxical ab-
end of the Briggs adaptor. dominal movement, intercostal space retractions, and
accessory ventilatory-muscle usage as the patient
breathes. Chest auscultation reveals bilaterally dimin-
IIIA2b(4)
ished and distant breath sounds. The patient appears to
22. A patient is receiving metaproterenol via a small- have labored breathing but is not complaining of dys-
volume nebulizer. The CRT notes that the patient’s pnea. Which of the following recommendations would
pulse increases from 80 beats/minute to 95 beats/ be appropriate to include in the patient’s chart?
minute. What should the CRT do at this time?
A. The patient appears to have asthma and should
A. Dilute the medication with normal saline. be evaluated via pre- and post-bronchodilator
B. Continue the treatment and monitor the patient. spirometry.
C. Stop the treatment and notify the physician. B. A sputum sample should be obtained for culture
D. Stop the treatment and perform chest physiotherapy. and sensitivity.
C. The patient apparently has pulmonary emphy-
IIIA2b(5) sema and should be instructed on diaphragmatic
23. A patient who has severe COPD and is in respiratory and pursed-lip breathing.
distress was given oxygen via a nasal cannula at 2 D. The patient might have a pneumothorax and
liters/min. Over time, the patient’s ventilatory rate pro- should be evaluated via chest radiography.

Chapter 5: Therapeutic Procedures 291

IIIA2c IIIA2e
26. During an IPPB treatment, the patient experiences an 29. The CRT enters the ICU and approaches the ventilator
episode of vomiting. What member of the health-care of a patient receiving pressure-limited IMV at a me-
team should be informed of the event? chanical rate of 10 breaths/minute. Based on assessing
the flow, volume, and pressure waveforms in Figure
A. the nurse
5-1, what problem can the CRT detect?
B. the physician
C. the dietician A. The patient is experiencing auto-PEEP.
D. the respiratory care supervisor B. A gas leak is occurring during inspiration.
C. The patient’s lung compliance has decreased.
IIIA2d D. Secretions have accumulated in the patient’s lungs.
27. Which of the following considerations are important to
take into account when scheduling patient therapy? IIIA2f
30. A patient who requires bronchodilator therapy cannot
I. patient visiting hours
breath-hold longer than five seconds. This fact was ob-
II. meal times
served when the patient attempted to inhale a bron-
III. other therapeutic procedures schedules
chodilator from an MDI. How should the CRT alter the
IV. patient attitude
bronchodilator therapy protocol?
A. II, III only
A. Have the patient activate the MDI more fre-
B. I, II, III only
quently during each treatment.
C. I, IV only
B. Deliver the bronchodilator using a small-volume
D. I, II, III, IV
nebulizer.
C. Incorporate a spacer along with the MDI.
IIIA2e D. Change the dose of the bronchodilator.
28. Which of the following types of clinical information
are available from waveform analysis during mechan- IIIA2f
ical ventilation?
31. The CRT is evaluating a 33-year-old non-smoking pa-
I. auto-PEEP tient in the emergency department and finds that the
II. compliance changes patient is short of breath, tachycardic, diaphoretic, and
III. airway resistance changes confused. The patient’s SpO2 on room air is 97%.
IV. WOB What should the CRT recommend at this time?
A. II, III only A. Continue monitoring the patient for any change in
B. I, IV only status.
C. II, III, IV only B. Initiate oxygen therapy with a nasal cannula at 2
D. I, II, III, IV liters/min.

L/s U

2
2.0

L UT

–0.5
60 PAW
cm
H2O
–20
40
PES
cm
H2O
–40
Figure 5-1: Flow, volume, and pressure waveforms reflecting pressure-limited IMV at a
mechanical rate of 10 breaths/min. Bear Medical Systems, Thermo Respiratory Group.

292 Chapter 5: Therapeutic Procedures

 C. Start oxygen therapy with a simple mask at 5 partment. Which of the following infection-control
liters/min. procedures should be used?
D. Administer oxygen therapy via an air entrainment
A. standard precautions
mask at 40%.
B. airborne precautions
C. droplet precautions
IIIA2f
D. contact precautions
32. Chest assessment indicates that retained secretions
have caused atelectasis of the right middle lobe in a IIIA3
45-year-old non-smoking patient. The patient has re-
36. The CRT is about to enter the room of a patient who is
ceived postural drainage therapy and has used the di-
infected with Mycoplasma pneumoniae and is cough-
rected cough technique. Both therapeutic measures
ing up copious amounts of mucus. Which of the fol-
have been ineffective. What should the CRT recom-
lowing precautions need to be observed?
mend to help remove the secretions and to facilitate the
reversal of the atelectasis? I. standard precautions
II. droplet precautions
A. Encourage the patient to cough more vigorously.
III. airborne precautions
B. Initiate incentive spirometry.
IV. contact precautions
C. Increase the patient’s FIO2.
D. Hydrate the patient and use positive expiratory A. II only
pressure. B. IV only
C. I, II only
IIIA3 D. I, III only
33. A patient who is known to be positive for the human
immunodeficiency virus (HIV) enters the emergency IIIA3
department. The CRT is summoned to perform an ar- 37. What type of isolation procedure, other than standard
terial puncture procedure on this patient. What type of precautions, is warranted for a patient who has the
precautions must the CRT take to protect herself? chicken pox?
I. Place a mask on the patient. A. droplet precautions
II. Don gloves. B. airborne precautions
III. Wear protective glasses. C. enteric precautions
IV. Wear a gown. D. contact precautions
A. II, III only
B. I, IV only IIIA3
C. II, III, IV only 38. Which of the following isolation procedures, other
D. I, II, III, IV than standard precautions, is appropriate for a pediatric
patient who has Hemophilus influenzae, type B infec-
IIIA3 tion?
34. What actions should be taken to reduce the incidence A. droplet precautions
of nosocomial infections for patients who are receiv- B. contact precautions
ing mechanical ventilation? C. vector precautions
I. Frequently drain the breathing circuit condensate D. airborne precautions
into the humidifier reservoir.
II. Replace the breathing circuit every eight hours. IIIA3
III. Wash hands before and after handling the patient 39. A fiberoptic bronchoscope was used on a patient who
and/or equipment. tested positive for pulmonary tuberculosis. Which of
IV. Before refilling the humidifier reservoir, discard the following methods of disinfection is appropriate
the unused water. for this instrument?
A. I, III, IV only A. 70% ethyl alcohol
B. II, III only B. glutaraldehyde
C. I, II only C. autoclaving
D. III, IV only D. ethylene oxide

IIIA3 IIIA3
35. The CRT is preparing to perform an arterial puncture 40. A reusable manual resuscitator and mask were used
procedure on a comatose patient in the emergency de- during CPR on a patient who had active pulmonary

Chapter 5: Therapeutic Procedures 293

 tuberculosis. How should the CRT handle these arti- D. The cuff is inflated until a 15 mm Hg cuff-to-
cles after the resuscitation procedure? tracheal wall pressure exists.
A. They should be bagged and labeled before being IIIB1a
44. Which statements refer to the procedure of inserting an
sent for decontamination and reprocessing.
oropharyngeal airway?
B. They should be rinsed with water, then wiped with
ethyl alcohol and bagged in the patient’s room be- I. The patient is placed in a supine position.
fore being decontaminated and reprocessed. II. The patient is placed in the Trendelenburg position.
C. They should be discarded in the patient’s room III. The buccal end of the airway is inserted and posi-
and not reused. tioned between the base of the tongue and the
D. Because of the nature of the contaminant, these posterior pharyngeal wall.
articles can be brought directly to the decontami- IV. The patient’s mouth might need to be forced open
nation and reprocessing area as is. with the thumb and index fingers crossed.
A. I, III, IV only
IIIB1a B. II, III, IV only
41. Which statement(s) represents the proper procedure(s) C. I, IV only
concerning endotracheal tube cuff care? D. II, III only
I. Before the cuff is to be deflated, the trachea
should be suctioned. IIIB1b
II. The oropharynx should be thoroughly suctioned 45. A 46-year-old male is receiving heated aerosol therapy
before cuff deflation. via a tracheostomy collar operated by a large-volume
III. Once the minimal leak has been established, the nebulizer. The CRT notices the heated nebulizer is set
cuff requires no further attention. at 50ºC, and the temperature at the patient connection
IV. A minimal leak established with the ventilator is 35ºC. What should she do at this time?
delivering low airway pressures would inade-
A. Do nothing, because these temperatures are fine.
quately seal the trachea if system pressure sud-
B. Raise the temperature at the humidifier to 55ºC.
denly increased.
C. Raise the temperature at the humidifier to 60ºC.
A. I, III only D. Lower the temperature at the humidifier to 40ºC.
B. II, IV only
C. I, II, IV only IIIB1a
D. III only 46. After tracheal intubation, proper tube placement
should be assessed by which procedures?
IIIB1a
I. auscultation of the chest
42. After attaching a cuff pressure manometer to the pilot II. observation for equal, bilateral chest expansion
balloon of an endotracheal tube inserted in a mechan- III. observation for an adequate cough mechanism
ically ventilated patient, the CRT observes an intracuff IV. portable chest X-ray
pressure reading of 40 cm H2O. He also notices that
only 500 ml of the set 900-ml tidal volume is being ex- A. I, II, III, IV
haled. What should the CRT do at this time? B. I, II, IV only
C. II, III only
A. Increase the tidal volume setting. D. I, IV only
B. Inject air into the cuff until a slight leak is per-
ceived around the cuff at end-inspiration. Questions #47 and #48 refer to the same patient.
C. Add more air into the cuff until the airway is com- (SITUATIONAL SET)
pletely sealed. A 5 ft. 10 in., 210-lb, 63-year-old male factory worker
D. Change the endotracheal tube. is admitted to the general medicine ward. He displays
the following physical signs and symptoms:
IIIB1a
• stocky body build and dusky skin color
43. Which statement refers to the minimal-leak technique?
• accessory ventilatory muscle usage
A. The cuff is inflated just to the point where no leak • audible wheezing via auscultation
occurs. • intercostal retractions
B. A minimal leak is allowed to occur around the • distended neck veins
cuff during exhalation. • peripheral edema
C. A minimal leak is allowed to occur around the • PaO2 59 mm Hg; PaCO2 68 mm Hg; pH 7.31
cuff during inhalation. • copious mucopurulent secretions

294 Chapter 5: Therapeutic Procedures

IIIB1b IIIB2a
47. Which disease process is this patient most likely ex- 51. While in the position for postural drainage of the pos-
hibiting? terior basal segments of both lungs, a patient com-
plains of a headache and dizziness when coughing.
A. bronchial asthma
The patient has a history of cerebral vascular acci-
B. pulmonary emphysema
dents. Which of the following actions is the most ap-
C. chronic bronchitis
propriate to take at this time?
D. bronchiectasis
A. Continue therapy while explaining to the patient
IIIE3 that these responses are normal.
B. Change the patient’s position to the semi-Fowler
48. What therapeutic interventions should be instituted on
position and reassess her before continuing in an-
this patient?
other area of the thorax.
I. venturi air-entrainment mask delivering 28% oxygen C. Continue therapy, but instruct the patient to clear
II. rotating tourniquets to reduce the strain on the heart her throat rather than cough deeply.
III. ultrasonic nebulization as necessary to facilitate D. Terminate the treatment.
the removal of secretions
IV. bronchodilator therapy IIIB2a
A. I, III, IV only 52. A COPD patient has a minimally productive cough
B. I, IV only and coarse rhonchi. Which of the following therapeu-
C. I, II, III only tic interventions can be indicated?
D. I, III only A. IPPB
B. chest physiotherapy
IIIB1d C. incentive spirometry
49. A patient is experiencing difficulty coughing up secre- D. aerosolized bronchodilator
tions while lying in his bed. What recommendations
could the CRT offer to this patient to improve his IIIB2a
cough mechanism? 53. Chest X-rays reveal an infiltrative process in the right
A. Instruct the patient to lower the bed to the supine middle lobe of a patient. How should this patient be
position. positioned to have chest physiotherapy applied to that
B. Instruct the patient to position the bed in an up- lung region?
right position. A. right side down, Trendelenburg position, with a
C. Have the patient put the head of the bed down and three-quarter turn toward the supine side
lie on his right side. B. supine Trendelenburg position
D. Have the patient put the head of the bed up and lie C. left side down, Trendelenburg position, with a
on his left side. three-quarter turn toward the supine side
D. left side down, flat
IIIB1e
50. The CRT has just inserted a orotracheal tube into a pa- IIIB2a
tient’s airway. Which of the following statements are 54. The CRT is summoned to evaluate an alert, oriented,
true concerning endotracheal tube placement and cuff post-operative patient who had lower abdominal
inflation pressure? surgery four hours ago. The patient has no history of
I. Normal insertion depth of the tube for an adult is lung disease but is experiencing retained secretions.
23 cm from the teeth. The patient is breathing 40% oxygen via an aerosol
II. The tube should not be secured until the place- mask. What should the CRT recommend for this pa-
ment of the tube is confirmed by auscultation. tient?
III. Intracuff pressure should be maintained less than A. postural drainage and directed coughing Q2h
20 mm Hg. B. CPAP Q4h
IV. Capnography might be helpful to determine tube C. expiratory positive airway pressure Q4h
placement. D. positive expiratory pressure Q3h
A. I, II, IV only
B. II, IV only IIIB2b
C. I, III only 55. Which of the following actions are important to take
D. I, II, III, IV while suctioning an intubated adult patient?

Chapter 5: Therapeutic Procedures 295

 I. Pre- and post-oxygenate the patient. IIIB2d
II. Limit the suctioning process to fewer than 10 to 60. A patient who has severe COPD is about to be dis-
15 seconds. charged from the hospital. The CRT has been asked to
III. Use a suction pressure of –80 mm Hg. instruct this patient on proper coughing techniques.
IV. Monitor the heart rate. Which of the following coughing instructions would
A. I, II only be appropriate for this patient?
B. II, III only A. The patient should place a pillow against her epi-
C. I, IV only gastrium and push in with her arms as she coughs.
D. I, II, IV only B. The patient should take a breath greater than her
FRC and exhale as forcefully as possible.
IIIB2b C. The patient should inhale moderately and exhale
56. When performing nasotracheal suctioning, what signs in short, staccato-like fashion.
are used to indicate that the catheter tip has been ad- D. The patient should stand or sit upright, inhale a
vanced into the trachea? tidal breath, then exhale and squeeze the thorax at
the costophrenic angle.
I. gagging
II. hoarse vocalization
III. coughing
IIIB2d
IV. dyspnea 61. A COPD patient using a flutter valve to facilitate se-
cretion removal is in need of generating a high pres-
A. I, III only sure from the device. What should the CRT instruct the
B. II, III only patient to do to accomplish this objective?
C. III, IV only
D. I, II, III, IV A. Hold the flutter device at smaller angle to the mouth.
B. Exhale at a higher flow rate.
IIIB2b C. Inspire a larger tidal volume.
D. Inspire more rapidly.
57. During endotracheal suctioning, a patient’s blood pres-
sure changed from 140/80 torr before the procedure to
100/50 torr. What should the CRT do at this time?
IIIB2d
62. The CRT is explaining to a patient how to use the flut-
A. Manually ventilate the patient. ter valve. How should the patient be instructed to con-
B. Instruct the patient to take a few deep, slow breaths. trol the pressure transmitted to the airways by this
C. Terminate the procedure immediately. advice?
D. Have the patient take a deep breath and cough.
A. Change the angle of the device.
IIIB2c B. Inspire a larger tidal volume.
C. Exhale at various flow rates.
58. A physician has ordered a bronchodilator to be adminis-
D. Use balls of different weights.
tered via IPPB to a post-thoracotomy, asthmatic patient
who has a vital capacity of 10 ml/kg. What recommen-
dation should the CRT make regarding this order?
IIIC1a
63. If a patient using the incentive spirometry device
A. Suggest chest physiotherapy to follow the IPPB shown in Figure 5-2 is able to maintain full displace-
treatments. ment of the balls in the first two chambers for two sec-
B. Recommend substituting incentive spirometry for onds, what would be the estimated inspired volume?
the IPPB.
C. Administer the bronchodilator via a small-volume
nebulizer. Decreased pressure zone (3) Mouthpiece (4)
D. Make no recommendation, and administer the
treatment as ordered.
IIIB2c
59. A patient whose cholinergic activity in the lungs was Plastic tube (2)
1200
blocked would be expected to experience which re- cc/sec 600
cc/sec
sponse? 900
cc/sec
Ball (1)
A. bronchoconstriction
B. hypersecretion of the goblet cells
C. decreased pulmonary blood flow
D. bronchodilatation Figure 5-2: TriFlow II incentive spirometer.

296 Chapter 5: Therapeutic Procedures

 A. 0.9 liter A. Increase the pressure being delivered to the patient.
B. 1.8 liters B. Encourage the patient to take deeper breaths.
C. 2.7 liters C. Instruct the patient to breathe slowly.
D. 4.0 liters D. Have the patient sit upright in the bed while tak-
ing the treatment.
IIIC1a
64. During the administration of aerosol therapy, the CRT IIIC1b
observes the patient breathing tidally. What should she 68. A patient is receiving IPPB by mask because of an inabil-
do at this time? ity to maintain a tight seal around a mouthpiece; however,
gastric distension is apparent with the treatment. What ac-
A. Nothing, because tidal breathing is appropriate
tion should be taken by the CRT to alleviate the problem?
during this therapeutic intervention.
B. Encourage the patient to breathe more quickly to A. Decrease the peak flow.
receive more airflow and aerosol into the lungs B. Splint over the abdomen during the treatment.
over time. C. Introduce a flanged mouthpiece.
C. Instruct the patient to breathe slowly and deeply D. Discontinue therapy.
and breath-hold at end-inspiration.
D. Have the patient arrive at his own ventilatory pat- IIIC1d
tern. 69. A patient who is receiving intermittent mandatory ven-
tilation at an FIO2 of 0.30 has an arterial PO2 of 50 torr.
IIIC1b What FIO2 would be needed to achieve an arterial PO2
65. If the preset pressure is being prematurely achieved of 70 torr? (Assume that this patient’s cardiopul-
when an IPPB treatment is being administered to a pa- monary status and respiratory quotient are constant.)
tient, what action(s) should be taken?
A. 0.35
I. Increase the machine sensitivity. B. 0.38
II. Reduce the flow rate. C. 0.42
III. Increase the pressure limit. D. 0.45
IV. Institute negative pressure during exhalation.
A. I, II, III only IIIC1d
B. II, III only 70. The CRT is called to the recovery room to assist with
C. II, IV only mechanically ventilating a 58-year-old obese, post-
D. III only operative patient who weighs 125 kg and is 5 ft. 3 in.
tall. Which of the following tidal volumes will be most
IIIC1b appropriate to ventilate this patient?
66. While receiving an IPPB treatment, an emphysema A. 350 ml
patient experiences air trapping from generating a B. 800 ml
forceful cough that terminates at mid-expiration. This C. 1,000 ml
patient can neither create an adequate intrathoracic D. 1,250 ml
pressure to overcome this air trapping and produce an
inspiration, nor can he complete his previous exhala- IIIC1d
tion. What action should the CRT take? 71. A patient is receiving mechanical ventilation with the
A. Get a mask and deliver positive pressure to the pa- following settings:
tient’s airways. • mode: SIMV
B. Attempt to coach the patient into relaxing and • mechanical ventilatory rate: 10 breaths/minute
spontaneously breathing slowly and deeply. • tidal volume: 800 ml
C. Have the patient breathe a bronchodilator admin- • FIO2: 0.60
istered via a hand-held nebulizer. • PEEP: 3 cm H2O
D. Perform the Heimlich maneuver on this patient.
Arterial blood-gas data are shown below.
IIIC1b PO2 44 torr
67. The CRT is administering an IPPB treatment to a pa- PCO2 39 torr; pH 7.39
tient who is in a Fowler position. During the treatment, HCO 3̄ 23 mEq/L
the patient complains of paresthesia. What can the
Which of the following ventilator-setting adjustments
CRT do to correct this problem?
is the most appropriate to make at this time?

Chapter 5: Therapeutic Procedures 297

 A. increasing the PEEP • mode: IMV
B. decreasing the tidal volume • mechanical ventilatory rate: 14 breaths/minute
C. increasing the FIO2 • mechanical tidal volume: 900 cc
D. increasing the mechanical ventilatory rate • FIO2: 0.60
• PEEP: 5 cm H2O
IIIC1d
His arterial blood gas and acid-base status at this time
72. The CRT has been called to the recovery room to set
indicate:
up a mechanical ventilator for a post-operative pa-
tient. The physician requests that standard operating PO2 58 torr
procedures for initiating mechanical ventilation be PCO2 33 torr
followed. Which of the following methods is the most pH 7.34
acceptable for establishing an initial tidal volume set-
Which of the following changes should the CRT sug-
ting?
gest to the physician?
A. 12 ml/kg of the patient’s ideal body weight
A. Increase the IMV rate to 18 breaths/minute.
B. multiplying the patient’s weight in pounds by 2.5
B. Decrease the IMV rate to 12 breaths/minute.
C. 10 ml/lb of the patient’s ideal body weight
C. Increase the FIO2 to 0.70.
D. 10 ml/kg of ideal body weight plus the patient’s
D. Increase the PEEP to 10 cm H2O.
anatomical dead space
IIIC1d
IIIC1d 76. An 85-kg male entered the emergency department
73. Which of the following calculations is generally used complaining of weakness of the extremities and dys-
to establish an initial ventilator tidal volume for an phagia for the past two days. The following ventilatory
adult patient? data were obtained over the last five hours:
I. multiplying the patient’s ideal body weight in
kilograms by 1 ml/kg VENTILATORY MEASUREMENTS
II. dividing the patient’s ideal body-surface area by
the PaCO2 1 p.m. RR: 12 bpm
III. using the Fick equation MIP: –40 cm H2O
VC: 3,000 ml
IV. multiplying the patient’s ideal body weight in
2 p.m. RR: 14 bpm
kilograms by approximately 10 ml/kg MIP: –36 cm H2O
A. I only VC: 2,550 ml
B. IV only 3 p.m. RR: 18 bpm
C. I, II only MIP: –30 cm H2O
VC: 2,200 ml
D. II, IV only
4 p.m. RR: 20 bpm
MIP: –22 cm H2O
IIIC1d VC: 1,750 ml
74. A pressure-cycled ventilator is functioning in the con- 5 p.m. RR: 32 bpm
trol mode as a short-term mechanical ventilator in the MIP: –15 cm H2O
VC: 750 ml
recovery room. The CRT increases the preset pressure
limit from 25 cm H2O to 30 cm H2O. What will be the
effect on the ventilatory rate and inspiratory time? Nei- The latest chest radiograph demonstrates reduced lung
ther the peak flow nor the sensitivity was changed. volumes, and the patient appears to be having more
difficulty swallowing. Which of the following recom-
A. Inspiratory time increases; ventilatory rate decreases. mendations should the CRT make at this time?
B. Inspiratory time decreases; ventilatory rate increases.
C. Inspiratory time decreases; ventilatory rate decreases. A. Intubate and mechanically ventilate the patient.
D. Inspiratory time increases; ventilatory rate increases. B. Have the patient perform incentive spirometry.
C. Obtain an arterial blood-gas sample.
D. Administer a -2 agonist via a small-volume nebu-
IIIC1d
lizer.
75. A motor vehicle accident victim has been receiving
volume-cycled mechanical ventilation for three days. IIIC1d
The patient has suffered bilateral lung contusions, a 77. A 63-year-old post-cardiac surgery patient weighing
minor head injury, and a broken femur. His current 90 kg (IBW) is being mechanically ventilated in the
mechanical ventilator settings follow. SIMV mode. Some of the ventilator settings include:

298 Chapter 5: Therapeutic Procedures

 • FIO2: 0.40 following actions should the CRT recommend at this
• ventilatory rate: 12 bpm time?
• VT: 950 cc
A. Inform the patient that this response is normal,
The patient’s overall minute ventilation is 15.2 liters/ and continue administering the treatment.
min., and the spontaneous ventilatory rate is 15 breaths/ B. Stop the treatment immediately, and notify the nurse.
min. Arterial blood gases at this time follow. C. Terminate the treatment, and call the physician to
suggest that the drug dosage is too weak.
PO2: –88 torr
D. Stop the treatment, and call the physician to sug-
PCO2: –33 torr
gest a different medication.
pH: –7.49
HCO 3̄ : –23 mEq/L IIIC1g
B.E.: –1 mEq/L
81. Which of the following medications is the most appro-
Which of the following recommendations should the priate to administer via aerosolization in order to
CRT make regarding the ventilation status of this patient? achieve bronchodilatation in a patient who is experi-
A. Increase the FIO2 to 0.50. encing an acute asthmatic episode?
B. Increase the tidal volume to 1 liter. A. ipratropium bromide
C. Decrease the ventilatory rate to 10 bpm. B. zafirlukast
D. Institute 10 cm H2O PEEP. C. albuterol
D. nedocromil
IIIC1f
78. The CRT is about to wean a 65-kg adult male from IIIC1h
mechanical ventilation. Which ventilatory rate and 82. The CRT is working with a 90-kg, 188-cm patient who
tidal volume most closely constitute a point at which has been receiving mechanical ventilation at an FIO2
to begin weaning with IMV? of 0.40 and is being evaluated for weaning. Which of
the following physiologic measurements meet the cri-
A. a ventilator rate of 12 breaths/minute; a VT of
teria for weaning?
12 cc/kg
B. a ventilator rate of 8 breaths/minute, with the pa- I. maximum inspiratory pressure of –30 cm H2O
tient triggering the machine an additional 6 times/ II. vital capacity of 1,500 cc
minute—delivering a VT of 10 cc/kg on each cycle III. PaO2 of 95 torr
C. a ventilator rate of 4 breaths/minute, accompanied IV. spontaneous tidal volume of 650 cc
by a spontaneous ventilatory rate of 12 breaths/
A. II, IV only
minute; 10 cc/kg VT delivered by the machine;
B. I, III only
and 8 cc/kg VT spontaneously breathed
C. I, II, III only
D. a ventilator rate of 5 breaths/minute, interspersed
D. I, II, III, IV
among a patient’s spontaneous rate of 12 breaths/
minute; both machine and patient VT at 10 cc/kg
IIIC2a
IIIC1g 83. A patient is receiving 10 cm H2O of CPAP by mask for
treatment of hypoxemia. Arterial blood gas data ob-
79. Which inhalational medications would be useful for
tained one hour later at an FIO2 of 0.90 follow.
treating an acute asthmatic episode?
PO2 50 torr
I. cromolyn sodium
PCO2 35 torr
II. Proventil
pH 7.35
III. terbutaline
IV. Mucomyst Which of the following actions should the CRT rec-
V. atropine ommend?
A. II, III, V only A. increasing the FIO2 to 1.0
B. I, II, III only B. increasing the CPAP level to 15 cm H2O
C. II, IV only C. increasing the flow in the CPAP system
D. II, III only D. intubating the patient and initiating mechanical
ventilation
IIIC1g
80. During a treatment with a -2 agonist via a small- IIIC2b
volume nebulizer, the patient complains of nervous- 84. A patient is being mechanically ventilated with the fol-
ness, trembling hands, and anxiousness. Which of the lowing settings:

Chapter 5: Therapeutic Procedures 299

 • mode: assist-control PO2 68 torr
• ventilatory rate: 10 breaths per minute PCO2 35 torr
• VT: 800 ml pH 7.42
• FIO2: 0.80
Which setting change would be most appropriate?
The patient is cycling on the ventilator with sponta-
A. increasing the FIO2
neous efforts at a rate of 14 breaths/min.
B. adding an end-inspiratory plateau
Arterial blood gases at this time reveal: C. changing to SIMV mode with a low rate
D. increasing the CPAP level
PO2 50 torr
PCO2 30 torr
pH 7.50 IIIC2c
87. A patient has returned to his room following a chole-
The CRT’s most appropriate action would be to: cystectomy. While the CRT is explaining incentive
A. Decrease the ventilatory rate. spirometry to the patient, the patient complains of
B. Increase the FIO2. breathing discomfort. Which of the following posi-
C. Recommend sedation of the patient. tions would optimize the patient’s breathing efforts?
D. Recommend addition of PEEP. A. reverse Trendelenburg position
B. supine position
IIIC2b C. on either side (lateral position)
85. A patient is being weaned from a mechanical ventila- D. semi-Fowler position
tor with the following settings:
• mode: SIMV IIID1
• FIO2: 0.30 88. Which radiographic technique provides the best method
• mechanical ventilatory rate: 4 breaths/minute for evaluating diaphragmatic activity?
• mechanical tidal volume: 800 ml A. the standard chest roentgenogram
• PEEP 10 cm H2O B. bronchography
The patient has a spontaneous ventilatory rate of 12 C. fluoroscopy
breaths/min and a spontaneous tidal volume of 800 ml. D. MRI

Arterial blood gas data indicate: IIID2

PO2 90 torr 89. A 53-year-old female who was sleeping when her
PCO2 38 torr house caught fire has been brought to the emergency
pH 7.42 department after her house was completely overcome
SO2 96% by the fire before she was awakened. She has been
Which of the following actions should the CRT rec- given 100% oxygen, and a STAT arterial blood gas is
ommend? obtained. The results are shown as follows:

A. Discontinue the ventilator and extubate the patient. PO2 300 torr
B. Decrease the FIO2 to 0.25 before discontinuing PCO2 23 torr
the ventilator. pH 7.58
C. Decrease the ventilatory rate to 2 breaths/minute HCO 3̄ 21 mEq/liter
before discontinuing the ventilator. B.E. + 1 mEq/liter
D. Decrease the PEEP to 5 cm H2O before discontin- Which of the following interpretations correspond
uing the ventilator. with the blood-gas and acid-base data obtained?
A. acute respiratory alkalosis
IIIC2b
B. acute respiratory acidosis
86. A 29-year-old heart-transplant patient is in the final C. chronic respiratory acidosis
stages of post-operative weaning from mechanical D. uncompensated metabolic alkalosis
ventilation. She is hemodynamically stable and non-
septic on a volume ventilator in the CPAP mode of 5 IIID2
cm H2O and an FIO2 of 0.50 with a spontaneous ven-
tilatory rate of 12 breaths/minute. The following blood 90. The driver of a motor vehicle was not wearing a seat
gas and acid-base data were received: belt and was thrown against the steering wheel when

300 Chapter 5: Therapeutic Procedures

 the car struck a utility pole. The patient is demonstrat- IIID3
ing paradoxical breathing of the right hemithorax and 93. For which of the following patients would the use of a
appears to be in respiratory distress. What immediate pulse oximeter be LEAST appropriate for monitoring
action needs to be taken by the CRT at this time? the patient’s oxygenation status?
A. Perform an arterial puncture procedure. A. a patient receiving mechanical ventilation at home
B. Call for a chest radiograph. B. an asthmatic patient in the emergency department
C. Intubate and mechanically ventilate the patient. C. a COPD patient participating in a pulmonary re-
D. Deliver 100% O2 to the patient. habilitation program
D. a smoke-inhalation victim
IIID2
91. A 30-year-old, 80-kg (IBW) patient who has status IIID4
asthmaticus is receiving controlled mechanical venti- 94. Sputum induction has been ordered for a pneumonia
lation with the following ventilator settings: patient. At the 6 A.M. shift report, the CRT is informed
that three previous attempts with a small-volume neb-
FIO2 : 0.40
ulizer have been unsuccessful. The CRT finds a 37-
ventilatory rate: 8 breaths/min.
year-old male, well nourished, with no previous
VT: 900 cc
history of pulmonary disease. What should the CRT
PEEP: 5 cm H2O
recommend to aid in obtaining the sputum induction?
Arterial blood-gas data at this time reveal:
A. bronchodilator
PO2 95 torr B. ultrasonic nebulizer
PCO2 52 torr C. mucomyst
pH 7.33 D. oxygen therapy
HCO 3̄ 27 mEq/L
B.E. 1 mEq/L IIID4
How should the CRT interpret this situation, based on 95. A CRT in a pulmonary rehabilitation center has been
the information presented? working with a chronic bronchitis patient for three
weeks. The patient is steadily recovering from a strep-
A. hyperoxemia tococcal pneumonia. A regimen of antibiotics and
B. refractory hypoxemia bronchial hygiene have effectively decreased sputum
C. hypoventilation production. What type of sputum production would the
D. hyperventilation CRT expect to see as the patient recovers from this
pneumonia?
IIID2
I. frothy
92. A 65-year-old patient is being transported to the radi- II. bloody
ology department. En route, the patient claims to be III. mucoid
experiencing shortness of breath and difficulty breath- IV. purulent
ing. His verbal expressions are choppy as he gasps for
air while wearing an air-entrainment mask delivering A. I, II only
40% oxygen. A point-of-care blood-gas analyzer indi- B. II, III, IV only
cates the following values: C. II, IV only
D. IV only
PaO2 52 torr
PaCO2 30 torr IIID5
pH 7.48
96. The CRT has been called to perform a STAT respiratory-
HCO 3̄ 24 mEq/L
protocol assessment on a trauma victim who suffered a
B.E. 0
closed head injury in a bicycling accident. During vi-
Based on these arterial blood-gas data, which of the tal sign assessment, the patient demonstrates a gradual
following evaluations reflects this patient’s situation? increase in the rate and depth of ventilation, followed
by a tapering of rate and depth. This ventilatory pattern
A. acute respiratory alkalemia with refractory hy-
is described as
poxemia
B. acute metabolic acidosis with hypoxemia respon- A. Biot’s breathing.
sive to oxygen therapy B. Cheyne-Stokes breathing.
C. acute ventilatory failure, together with lactic acidosis C. apneustic breathing.
D. chronic hypercapnia with severe shunting D. ataxic breathing.

Chapter 5: Therapeutic Procedures 301

IIID5 IIID7
97. A patient who has a history of Gullain-Barré syndrome 99. The CRT is about to change the inspiratory time on a
has been admitted to the hospital. The patient has the time-cycled, pressure-limited ventilator that provides a
following bedside pulmonary function results: ventilatory rate setting. How does lengthening the inspi-
ratory time affect the ventilatory rate and the I:E ratio?
VT: 450 ml
VC: 1,220 ml A. Neither the ventilatory rate nor the I:E ratio will
MIP: –42 cm H2O change.
B. The ventilatory rate will not change, but the I:E
Two hours later, the CRT re-evaluates the patient and
ratio will increase.
obtains the following bedside pulmonary function data:
C. The ventilatory rate will decrease, and the I:E ra-
VT: 300 ml tio will increase.
VC: 800 ml D. The ventilatory rate will decrease while the I:E ra-
MIP: –25 cm H2O tio remains constant.
Which of the following recommendations would be
appropriate for the CRT to make at this time? IIID7
100. Which statement(s) correctly describe(s) the I:E ratio
A. Obtain more bedside pulmonary function data in as it applies to a patient who is receiving controlled
two hours. mechanical ventilation?
B. Intubate and ventilate the patient.
C. Administer incentive spirometry Q2h. I. The mean airway pressure will increase as expi-
D. Deliver an aerosolized bronchodilator Q4h. ratory time is lengthened, while the inspiratory
time, V̇, and VT will remain constant.
IIID6 II. Keeping all other settings constant while length-
ening the inspiratory time lowers the mean in-
98. After adjusting the sensitivity control on a mechanical
trathoracic pressure.
ventilator, the CRT views the pressure-volume curve
III. A large I:E ratio tends to decrease venous return.
shown in Figure 5-3 obtained from a patient receiving
assist/control ventilation. How should the CRT inter- A. I only
pret this curve? B. II, III only
C. II only
1,000 D. III only
900
800 IIID7
Volume (ml)

700 101. Which of the following factors affect the PaO2 in me-
600 chanically ventilated patients?
500
400 I. tidal volume
300 II. mean airway pressure
200 III. I:E ratio
100 IV. FIO2
-10 0 10 20 30 40 A. I, II, III only
Pressure (cm H2O) B. I, IV only
C. III, IV only
Figure 5-3: Pressure-volume waveform from a patient who D. I, II, III, IV
is receiving assist/control ventilation.
IIID7
A. The sensitivity level has been adequately adjusted.
102. Which of the following mechanical ventilator alarms
B. The ventilator needs to be made more sensitive to
are considered to be disconnect alarms?
the patient’s spontaneous inspiratory efforts.
C. The ventilator needs to be made less sensitive to I. peak pressure
the patient’s spontaneous inspiratory efforts. II. low pressure
D. The patient is physically incapable of initiating a III. low-exhaled volume
spontaneously generated breath. IV. minimum minute ventilation

302 Chapter 5: Therapeutic Procedures

 A. I, III, IV only A. 0.50 liter
B. I, II, IV only B. 0.72 liter
C. II, III only C. 1.20 liters
D. II, III, IV only D. 1.34 liters

IIID7 IIID8
103. A patient receiving mechanical ventilation has a PIP of Questions #107 and #108 refer to the same information.
46 cm H2O and a plateau pressure of 38 cm H2O. What (SITUATIONAL SET)
pressure is required to overcome the resistance of the
107. A Puritan-Bennett all-purpose nebulizer operating at
airways?
10 liters/minute, delivering an FIO2 of 0.70, produces
A. 0.83 cm H2O what total liter flow?
B. 1.20 cm H2O
A. 3 liters/minute
C. 8.00 cm H2O
B. 4 liters/minute
D. 84.00 cm H2O
C. 6 liters/minute
D. 16 liters/minute
IIID7
104. What is the tidal volume of a patient who has had the IIID8
following ventilatory measurements continuously for
the last six hours? 108. Determine the air/O2 ratio in the preceding problem.

Cstatic 25 ml/cm H2O A. 0.3:1.0

PIP 35 cm H2O B. 0.4:1.0
Pplateau 25 cm H2O C. 0.6:1.0
PEEP 5 cm H2O D. 1.6:1.0

A. 750 ml IIID9
B. 625 ml
C. 500 ml 109. Over a four-day period, the CRT notes a steadily in-
D. 375 ml creasing cuff volume necessary to maintain an in-
tracuff pressure of less than 20 mm Hg. Which of the
following conditions could be responsible for this sit-
IIID7
uation?
105. Upon entering the adult ICU to conduct ventilator
rounds, the CRT notices the visual display for the I:E ra- I. a low-compliant cuff
tio alarm lighting. The patient is being ventilated in the II. tracheomalacia
control mode with a square waveflow pattern. Which of III. tissue swelling around the cuff
the following actions might correct this situation? IV. a small leak in the cuff

I. initiating an inflation hold A. II only

II. increasing the peak flow rate B. II, III only
III. decreasing the tidal volume C. I, III, IV only
IV. decreasing the respiratory rate D. IV only

A. I, III only
B. III, IV only IIID10
C. II, III, IV only 110. While auscultating a mechanically ventilated patient,
D. I, II, IV only the CRT perceives sounds described as “creaking
leather.” This sound is most likely caused by which
IIID7 clinical condition?
106. Calculate the volume delivered by a time-cycled, A. pneumothorax
volume-limited, constant-flow generator when the in- B. bronchopleural fistula
spiratory time is 1.2 seconds and the inspiratory flow C. pleural friction rub
rate is 60 liters/minute. D. pleural effusion

Chapter 5: Therapeutic Procedures 303

 STOP
You should stop here to evaluate your performance on the 110 questions relating to matrix sections IIIA, IIIB, IIIC,
and IIID. Use the Entry-Level Examination Matrix Scoring Form pertaining to Therapeutic Procedures (sections
IIIA through IIID) in Table 5-5. Then refer to the Therapeutic Procedures portion of the NBRC Entry-Level Exam-
ination Matrix in Table 5-6 to continue your assessment.
Table 5-5: Therapeutic Proceures: Entry-Level Examination Matrix Scoring Form

Entry-Level Examination Therapeutic Therapeutic Therapeutic

Procedures Procedures Procedures
Content Area Item Number Answered Correctly Area Score

IIIA1. Explain planned therapy and 1, 2, 3, 4, 5, 6, 7, 8, 9 _  100 = ____%

goals to patient. 9

IIIA2. Maintain records and 10, 11, 12, 13, 14, 15, 16, 17,
communication. 18, 19, 20, 21, 22, 23, 24, 25, __  100 = ____%
26, 27, 28, 29, 30, 31, 32 23

IIIA3. Protect patient from 33, 34, 35, 36, 37, 38, 39, 40 _  100 = ____%
nosocomial infection. 8

IIIB1. Maintain a patent airway. 41, 42, 43, 44, 45, 46, 47, 48, __  100 = ____%
49, 50 10 __  100 = ____%
___
110
IIIB2. Remove bronchopulmonary 51, 52, 53, 54, 55, 56, 57, 58, __  100 = ____%
secretions. 59, 60, 61, 62 12

IIIC1. Achieve adequate spontan- 63, 64, 65, 66, 67, 68, 69, 70,
eous and artificial ventilation. 71, 72, 73, 74, 75, 76, 77, 78, __  100 = ____%
79, 80, 81 19

IIIC2. Achieve adequate arterial 82, 83, 84, 85, 86, 87 _  100 = ____%
and tissue oxygenation. 6

IIID1–10. Evaluate and monitor patient’s 88, 89, 90, 91, 92, 93, 94, 95,
response to respiratory care. 96, 97, 98, 99, 100, 101, 102, __  100 = ____%
103, 104, 105, 106, 107, 108, 23
109, 110

304 Chapter 5: Therapeutic Procedures

Table 5-6: NBRC Certification Examination for Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
N

N
(5) pulse oximetry, heart rhythm,
III. Initiate, Conduct, and capnography x
c. communicate information regarding
Modify Prescribed patient’s clinical status to appropriate
Therapeutic Procedures members of the health-care team x
SETTING: In any patient care d. communicate information relevant to
setting, the respiratory therapist coordinating patient care and discharge
communicates relevant informa- planning [e.g., scheduling, avoiding
tion to members of the health- conflicts, sequencing of therapies] x
care team, maintains patient e. apply computer technology to patient
records, initiates, conducts, and management [e.g., ventilator waveform
modifies prescribed therapeutic analysis, electronic charting, patient
procedures to achieve the de- care algorithms] x
sired objectives and assists the f. communicate results of therapy and
physician with rehabilitation and alter therapy per protocol(s) x
home care. 3. Protect patient from noscomial infection
15 36 28
by adherence to infection control policies
and procedures [e.g., universal/standard
precautions, blood and body fluid
A. Explain planned therapy and goals to
precautions] x
patient, maintain records and
communication, and protect patient B. Conduct therapeutic procedures to
from nosocomial infection. 2* 3 0 maintain a patent airway and remove
1. Explain planned therapy and goals to bronchopulmonary secretions. 2 3 0
patient in understandable terms to achieve 1. Maintain a patent airway, including the
optimal therapeutic outcome, counsel care of artificial airways:
patient and family concerning smoking a. insert oro- and nasopharyngeal airway,
cessation, disease management education x** select endotracheal or tracheostomy
2. Maintain records and communication: tube, perform endotracheal intubation,
a. record therapy and results using change tracheostomy tube, maintain
conventional terminology as required proper cuff inflation, position of
in the health-care setting and/or by endotracheal or tracheostomy tube x
regulatory agencies [e.g., date, time, b. maintain adequate humidification x
frequency of therapy, medication, and c. extubate the patient x
ventilatory data] x d. properly position patient x
b. note and interpret patient’s response e. identify endotracheal tube placement
to therapy by available means x
(1) effects of therapy, adverse reactions, 2. Remove bronchopulmonary secretions:
patient’s subjective and attitudinal a. perform postural drainage, perform
response to therapy x percussion and/or vibration x
(2) verify computations and note b. suction endotracheal or tracheostomy
erroneous data x tube, perform nasotracheal or
(3) auscultatory findings, cough and orotracheal suctioning, select closed-
sputum production and characteristics x system suction catheter x
(4) vital signs [e.g., heart rate, c. administer aerosol therapy and
respiratory rate, blood pressure, prescribed agents [e.g., bronchodilators,
body temperature] x corticosteroids, saline, mucolytics] x

*The number in each column is the number of item in that content area and the cognitive level contained in each
examination. For example, in category I.A., two items will be asked at the recall level, three items at the application level,
and no items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the
respective column (Recall, Application, and Analysis).

Chapter 5: Therapeutic Procedures 305

Table 5-6: (Cont.)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
IS

IS
N

N
N

N
d. instruct and encourage 3. Perform arterial puncture, capillary blood
bronchopulmonary hygiene techniques gas sampling, and venipuncture; obtain
[e.g., coughing techniques, autogenic blood from arterial or pulmonary artery
drainage, positive expiratory pressure lines; perform transcutaneous O2/CO2,
(PEP) device, intrapulmonary percussive pulse oximetry, co-oximetry, and
ventilation (IPV), Flutter®, High capnography monitoring x
Frequency Chest Wall Oscillation 4. Observe changes in sputum production
(HFCWO)] x and consistency, note patient’s subjective
response to therapy and mechanical
C. Conduct therapeutic procedures to achieve
ventilation x
adequate ventilation and oxygenation. 2 5 9
5. Measure and record vital signs, monitor
1. Achieve adequate spontaneous and
cardiac rhythm, evaluate fluid balance
artificial ventilation:
(intake and output) x
a. instruct in proper breathing techniques,
6. Perform spirometry/determine vital
instruct in inspiratory muscle training
capacity, measure lung compliance and
techniques, encourage deep breathing,
airway resistance, interpret ventilator flow,
instruct and monitor techniques of
volume and pressure waveforms,
incentive spirometry x
measure peak flow x
b. initiate and adjust IPPB therapy x
7. Monitor mean airway pressure, adjust
c. select appropriate ventilator
and check alarm systems, measure tidal
d. initiate and adjust continuous
volume, respiratory rate, airway pressures,
mechanical ventilation when no settings
I:E, and maximum inspiratory pressure
are specified and when settings are
(MIP) x
specified [e.g., select appropriate tidal
8. Measure FiO2 and/or liter flow x
volume, rate, and/or minute ventilation]
9. Monitor cuff pressures x
e. initiate nasal/mask ventilation, initiate
10. Auscultate chest and interpret changes
and adjust external negative pressure
in breath sounds x
ventilation [e.g., culrass]
f. initiate and adjust ventilator modes [e.g.,
A/C, SIMV, pressure-support ventilation
(PSV), pressure-control ventilation (PCV)] x
g. administer prescribed bronchoactive
agents [e.g., bronchodilators,
corticosteroids, mucolytics] x
h. institute and modify weaning procedures x
2. Achieve adequate arterial and tissue
oxygenation:
a. initiate and adjust CPAP, PEEP, and
non-invasive positive pressure x
b. initiate and adjust combinations of
ventilatory techniques [e.g., SIMV,
PEEP, PS, PCV] x
c. position patient to minimize hypoxemia,
administer oxygen (on or off ventilator),
prevent procedure-associated
hypoxemia [e.g., oxygenate before and
after suctioning and equipment changes] x
D. Evaluate and monitor patient’s response
to respiratory care. 2 6 2
1. Recommend and review chest X-ray x
2. Interpret results of arterial, capillary, and
mixed venous blood gas analysis

306 Chapter 5: Therapeutic Procedures

 Therapeutic Procedures Assessment (continued)
The following 125 questions refer to Entry-Level Examination Matrix sections IIIE, IIIF, and IIIG.
NOTE: You should stop to evaluate your performance on the 125 questions pertaining to the matrix sections IIIE, IIIF, and IIIG.
Please refer to the NBRC Entry-Level Examination Matrix designations located at the end of the content area IIIG on
page 327 and 328 of Therapeutic Procedures to assist you with evaluating your performance on the test items in this
section.
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the one that is best in each case, then blacken the corresponding space on the
answer sheet found in the front of this chapter. Good luck.
IIIE1c gen via a large-volume nebulizer. What should the
111. The CRT has been summoned to evaluate a 45-year- CRT do at this time?
old, two-day post-abdominal surgery patient who is
A. Analyze the FIO2 being delivered to the patient.
conscious, oriented, afebrile, and dyspneic. Her vital
B. Use a pulse oximeter to measure the patient’s SpO2.
signs are as follows:
C. Change the O2 delivery device to a nasal cannula
• Temperature: 37ºC operating at 4 liters/min.
• Respiratory rate: 30 breaths/min. D. Switch the patient to a heated humidifier deliver-
• Heart rate: 115 beats/min. ing a high flow of oxygen.
This patient has been receiving flow-oriented incentive
spirometry for the last two days at a frequency of 10 IIIE1f
sustained maximum inspirations TID. Auscultation of 114. For which of the following types of surgical patients
the patient’s thorax reveals diminished breath sounds would the Trendelenburg position during postural
in both lung bases, accompanied by a few late inspira- drainage be contraindicated?
tory crackles. The CRT is asked to make a recommen-
A. thoracic surgery
dation regarding this patient’s therapeutic regimen.
B. abdominal surgery
Which of the following modifications to therapy
C. orthopedic surgery
should the CRT recommend?
D. cranial surgery
A. Administer volume-oriented IPPB TID.
B. Implement flutter therapy TID. IIIE1i(1)
C. Increase the frequency of sustained maximum in-
spirations to Q1h. 115. The CRT is working with a mechanically ventilated
D. Have the patient perform active cycle breathing, patient who is receiving controlled-volume ventilation.
followed by aerosol therapy Q6h. If an inflation hold were activated, what effect would
this ventilation change have on the ventilator system?
IIIE1d(2) A. increased PIP
112. A patient is receiving an FIO2 of 0.40 at 10 liters/minute B. increased mean airway pressure
via a Briggs adaptor with 100 cc of reservoir tubing at- C. decreased static pressure
tached to its distal end. A fine aerosol mist continuously D. decreased tidal volume
emerges from the distal tip of the reservoir tubing
throughout the patient’s ventilatory cycle. What action IIIE1i(1)
needs to be taken by the CRT at this time? 116. A patient who has acute respiratory failure is being me-
A. Increase the FIO2 to 0.60. chanically ventilated in the volume control mode with a
B. No action needs to be taken. constant-flow ventilator. The PIP consistently reaches
C. Remove 50 cc of the reservoir tubing. 68 cm H2O with each breath. How can the CRT modify
D. Increase the source gas flow rate. this patient’s mechanical ventilatory support to reduce
the risk of barotrauma?
IIIE1d(2) A. Initiate inverse-ratio ventilation.
113. The CRT enters the room of a patient who is recover- B. Start pressure-support ventilation.
ing from an acute asthmatic episode. Immediately, the C. Begin assist/control ventilation.
CRT notices the patient receiving supplemental oxy- D. Institute pressure-control ventilation.

Chapter 5: Therapeutic Procedures 307

IIIE1i(1) fant who is receiving CPAP at 5 cm H2O with an FIO2 of
117. The CRT has inserted a suction catheter down an en- 0.70. Arterial blood-gas values at this time reveal:
dotracheal tube of a patient receiving mechanical ven- PO2 145 torr
tilation. Just before starting to withdraw the catheter, PCO2 44 torr
the CRT observes an ECG tracing shown in Figure pH 7.37
5-4 appear on the cardiac monitor. HCO 3̄ 25 mEq/L
What should the CRT do at this time? B.E. 1 mEq/L

A. Continue with the suction procedure, because this Which of the following changes should the CRT rec-
response is acceptable. ommend?
B. Immediately withdraw the suction catheter and A. Reduce the FIO2 and maintain the 5 cm H2O CPAP.
hyperoxygenate the patient. B. Reduce the CPAP and maintain the FIO2 of 0.70.
C. Immediately withdraw the suction catheter and C. Reduce both the CPAP and the FIO2.
initiate a code. D. Reduce the FIO2 and terminate the CPAP.
D. Withdraw the suction catheter immediately and
reconnect the patient to the ventilator. IIIE1a
120. During the administration of a nebulized beta-adrenergic
IIIE1i(1) bronchodilator, the patient complains of palpitations,
118. A 70-year-old, 80-kg patient with moderate pulmonary anxiousness, dyspnea, and lightheadedness. The CRT
emphysema is receiving mechanical ventilatory sup- immediately determines the patient’s blood pressure and
port in the assist/control mode via the following set- heart rate to be 190/115 torr and 125 beats/minute,
tings: respectively. Additionally, the patient’s ventilatory rate is
33 breaths/minute. What actions are appropriate for the
• respiratory rate: 12 breaths/min.
CRT to take at this time?
• tidal volume: 875 ml
• FIO2: 0.30 A. Initiate volume-oriented IPPB.
B. Continue the therapy and monitor the patient.
The patient is exhibiting no spontaneous ventilatory
C. Discontinue administering the beta agonist and
efforts. Arterial blood gases at this time reveal:
initiate a bland aerosol treatment.
PaO2 65 torr D. Discontinue the beta-agonist treatment, notify the
PaCO2 60 torr physician, and continue monitoring the patient.
pH 7.33
HCO 3̄ 33 mEq/L IIIE1a
B.E. 9 mEq/L 121. A patient who has vocal cord paresis with accompany-
ing tracheal stenosis is receiving mechanical ventila-
Which of the following ventilatory-setting changes tion. The patient is nasally intubated with a 6.0 mm
should the CRT recommend at this time? I.D. endotracheal tube. The physician is concerned
about the potentially high WOB imposed by the endo-
A. Increase the FIO2 to 0.40.
tracheal tube and asks the CRT for advice. Which rec-
B. Increase the ventilatory rate to 14 breaths/min.
ommendation is appropriate at this time?
C. Initiate pressure-support ventilation with 15 cm H2O.
D. No change in the patient’s ventilatory status is A. Institute pressure-support ventilation.
necessary. B. Administer Q2h aerosolized bronchodilator treat-
ments.
IIIE1i(1) C. Initiate pharmacologic paralysis and controlled
119. While working in the NICU, the physician asks the CRT mechanical ventilation.
to recommend a change in therapy on a 10-day-old in- D. Extubate and reintubate with an oral endotracheal
tube.

Figure 5-4: ECG tracing.

308 Chapter 5: Therapeutic Procedures

IIIE1a IIIE1b(1)
122. Which of the following cardiopulmonary measure- 125. A patient is receiving an IPPB treatment via a PR-2
ments meet the criteria for deciding to discontinue me- operating off a blender set at 35% oxygen. Upon
chanical ventilation? analysis of the delivered oxygen concentration, the
oxygen analyzer indicates 30%. What is the probable
I. an MIP of –25 cm H2O
cause of this situation?
II. a vital capacity greater than or equal to 10 ml/kg
of the patient’s ideal body weight A. The sensitivity of the machine is set too low.
III. VD/VT = 0.85 B. Back pressure in the system is reducing the air en-
IV. Q̇ S/Q̇ T = 0.40 trainment.
C. The peak pressure is set too high.
A. III, IV only
D. The terminal flow control is operational.
B. I, III, IV only
C. I, II only
IIIE1b(1)
D. I, III only
126. While administering an IPPB treatment to a patient,
the CRT notices that the machine pressure gauge de-
IIIE1a flects to –2 cm H2O before the machine cycles to in-
123. A patient receiving IPPB treatments suddenly com- spiration. What should the CRT do in this situation?
plains of dyspnea and severe, sharp pain during inspi- A. Do nothing, because this situation is normal.
ration. What should the CRT do in this situation? B. Stop the treatment to allow the patient to relax and
A. Allow the patient to rest before continuing the slow down her ventilations.
treatment. C. Adjust the sensitivity control to allow the patient
B. Discontinue the treatment and notify the patient’s to cycle on the ventilator more easily.
physician. D. Reduce the preset pressure, because it is probably
C. Change the therapy to incentive spirometry Q1h. too high for the patient to tolerate.
D. Reassure the patient before continuing the therapy.
IIIE1c
127. A patient who is receiving incentive spirometry is con-
IIIE1a
sistently not achieving the preset goal on the device.
124. A post-op thoracotomy patient displays the following What action is recommended to correct this situation?
clinical signs:
A. Re-evaluate the goal that has been set for the patient.
1. inspection B. Get a new device, because this one does not func-
— increased ventilatory rate tion properly.
— mediastinal shift to the right C. Encourage the patient until she reaches the goal.
2. palpation D. Change the therapy to IPPB.
— absent tactile fremitus in the left lower lung
region IIIE1c
— decreased thoracic movement on the left side 128. A 24-year-old female has sustained a broken arm and
fractured ribs in a windsurfing accident. She has been
3. percussion
instructed to use an incentive spirometer by taking
— dull over the left lower lung region
slow, deep, sustained breaths for approximately 10
4. auscultation breaths every hour. Two days later, the patient reports
—absent over the left lower lung region that she has been able to reach the incentive goal
pointer set at the 600 cc mark with every inspiratory
After two days of various forms of hyperinflation ther- effort, although it causes pain at the rib-fracture site.
apy, the CRT determines that these clinical findings What should the CRT recommend?
persist. What action should the CRT take at this time?
I. a rest period of 30 seconds to one minute between
A. Terminate the hyperinflation treatments and order inspirations
a chest radiograph. II. that pain medication be given to the patient every
B. Increase the frequency of the hyperinflation ther- hour incentive spirometry is performed
apy. III. that the patient perform a rapid inspiration but
C. Suggest bronchodilator therapy. continue to breath-hold at end-inspiration
D. Recommend the initiation of bronchial-hygiene IV. that the incentive goal pointer be advanced to a
therapy. higher inspiratory volume

Chapter 5: Therapeutic Procedures 309

 A. I, III only ing at 12 liters/minute. The following data are ob-
B. I, IV only tained:
C. II, IV only
heart rate: 76 beats/minure
D. I, II, III only
ventilatory rate: 14 breaths/minute
SpO2: 97%
IIIE1d(3)
129. A patient is receiving aerosol therapy with 5.0 cc of Which of the following actions should the CRT rec-
normal saline to induce sputum production. The pa- ommend at this time?
tient has been receiving the therapy Q4 hours for two A. Decrease the FIO2 to 0.50.
days with no results. What recommendations should B. Decrease the flow rate to 10 liters/minute.
the CRT make at this time? C. Add 5 cm H2O PEEP.
A. Do not change the therapy; a specimen will be D. Add 5 cm H2O PEEP and decrease the FIO2 to 0.28.
produced eventually.
B. Change the normal saline to a hypertonic saline IIIE1e(1)
solution. 133. A COPD patient is breathing 1 liter/min. of oxygen via
C. Discontinue the therapy, because it is not benefit- a reservoir cannula connected to an oxygen concentra-
ing the patient. tor at the patient’s home. Prior to this time, the patient
D. Discontinue the aerosol and initiate IPPB with the was using the same oxygen-delivery device supplied
same medication. by a liquid-oxygen system. The patient’s SpO2 with
the reservoir cannula connected to the liquid-oxygen
IIIE1e(1) system was 93%. The SpO2 reading is now 85%, and
130. A COPD patient is receiving IPPB therapy with 0.3 ml the patient is showing signs of respiratory distress.
of 2.25% racemic epinephrine at an FIO2 of 1.0. After What should the CRT do at this time?
five minutes of treatment, the patient becomes sleepy A. Administer 28% oxygen via an air-entrainment
and non-responsive. Measurement of his vital signs re- mask connected to an E cylinder.
veals a heart rate of 88 beats/minute and shallow B. Increase the oxygen flow rate to the reservoir can-
breathing at a ventilatory rate of 6 breaths/minute. nula to 2 liters/min.
What is the probable explanation for this response? C. Switch to a standard nasal cannula operating at 2
A. This response to the treatment is normal. liters/min.
B. The patient is responding to too large of a dose of D. Replace the reservoir nasal cannula with a pen-
medication. dant nasal cannula.
C. The patient is experiencing oxygen-induced hy-
poventilation. IIIE1e(3)
D. The patient needs to be motivated and encouraged 134. A socially active patient with low FIO2 needs is re-
during the treatment. ceiving home oxygen. The patient has been prescribed
a standard nasal cannula at 2 liters/min. to be used with
IIIE1e(1) an oxygen concentrator. The patient is often non-
131. The CRT is caring for a stable, post-operative patient re- compliant with the oxygen prescription when taking
ceiving oxygen at 3 liters/minute via a nasal cannula. A trips in the car, when walking around the neighbor-
sleeping pill has just been administered by the nurse, and hood, and when visiting friends. The patient complains
the patient has now developed a slow, shallow breathing about the limited length of time this system provides
pattern with a tidal volume of approximately 250 cc. To him when he is away from home and frequently avoids
ensure the delivery of a stable FIO2, which of the fol- using his cannula because of cosmetic reasons. Which
lowing interventions should the CRT recommend? of the following oxygen-delivery systems would pro-
vide this patient with the most mobility and the least
A. Increase the nasal cannula flow rate to 6 liters/ self-consciousness?
minute.
B. Change to a partial rebreathing mask. A. transtracheal oxygen catheter attached to a portable
C. Change to a simple mask at 6 liters/minute. liquid-oxygen unit
D. Change to a 30% air-entrainment mask. B. a pendant nasal cannula using a portable liquid-
oxygen unit as a source
C. a demand-flow oxygen-delivery device attached
IIIE1e(1)
to a portable liquid-oxygen unit
132. An intubated patient is administered a continuous, D. a reservoir nasal cannula connected to an E cylin-
heated aerosol via a T-piece at an FIO2 of 0.60, operat- der of oxygen

310 Chapter 5: Therapeutic Procedures

IIIE1e(3) IIIE1g(3)
135. The CRT enters the home of a post-acute care patient. 139. A patient receiving volume-control ventilation is having
The patient is wearing a nasal cannula with a flow rate his oropharynx routinely suctioned with a Yankauer suc-
of 5 liters/min. flowing through a bubble humidifier. tion tip. The CRT now observes a rise in the ventilator’s
The patient needs humidified oxygen at 40%. Which PIP with no change in the plateau pressure. Upon aus-
of the following oxygen-delivery systems is most suit- cultation of this patient’s chest, the CRT hears inspira-
able for this patient? tory crackles. What should the CRT do at this time?
A. A pendant nasal cannula operating at 2.5 liters/ A. Set the vacuum pressure to –140 mm Hg.
min. through a bubble humidifier. B. Perform tracheobronchial suctioning.
B. An oxygen mask connected to a compressor-driven C. Recommend an in-line, aerosolized bronchodilator.
humidifier with oxygen bled in at a low flow rate. D. Lower the high-pressure limit.
C. An oxygen powered air-entrainment nebulizer set
at 40%. IIIE1h(3)
D. The oxygen-delivery system presently in use is 140. A 10-year-old child who has cystic fibrosis requires
meeting the patient’s oxygen requirements. frequent nasotracheal suctioning to remove thick, tena-
cious, and difficult-to-suction secretions. The CRT
IIIE1f notes the suction pressure level at –80 mm Hg. Which
136. A 48-year-old male receiving 40% oxygen is in his of the following modifications is the most appropriate
second postoperative day recuperating from coronary recommendation to aid in the clearance of secretions?
artery bypass surgery. Auscultation of the chest reveals
A. Increase I.V. fluids.
bilaterally decreased breath sounds in the bases. The
B. Apply suction for a greater length of time.
chest radiograph shows right hemidiaphragm elevation
C. Adjust the suction pressure to –100 mm Hg.
and air bronchograms in both lung bases. The patient
D. Change the nasopharyngeal airway more frequently.
has been receiving IPPB therapy at 15 cm H2O since
the surgery. Which of the following modifications to
therapy would be appropriate at this time? IIIE1i(1)
141. A patient is receiving mechanical ventilation following
A. Increase the patient’s FIO2. surgery for intracranial bleeding. The ventilator set-
B. Institute bronchial hygiene therapy with humidifi- tings are as follows:
cation and lung-expansion therapy.
C. Increase the delivery pressure delivered by the • mode: control
IPPB machine and administer a bronchodilator. • tidal volume: 900 ml
D. Initiate incentive spirometry and chest physiotherapy. • ventilatory rate: 14 breaths/minure
• peak flow rate: 60 liters/minute
IIIE1g(1) • FIO2: 0.30
137. While auscultating the chest of an orally intubated pa-
As the CRT enters the room, the pressure-limit alarm
tient receiving mechanical ventilation, the CRT hears
sounds. A review of the ventilator flow sheet reveals
bilaterally decreased breath sounds. The CRT can also
the following data:
feel gas movement through the patient’s mouth. Which
of the following actions would be most appropriate to PIP: 40 cm H2O
correct this problem? plateau pressure: 35 cm H2O
compliance: 25 ml/cm H2O
A. Deflate the endotracheal tube cuff.
pressure limit: 45 cm H2O
B. Remove the oral endotracheal tube and nasally in-
low-pressure alarm: 30 cm H2O
tubate the patient.
C. Advance the endotracheal tube about 2 cm.
What should the CRT do at this time?
D. Decrease the PIP.
A. Decrease the tidal volume to 800 ml.
IIIE1g(2) B. Decrease the peak flow rate to 40 liters/minute.
138. Calculate the relative humidity of a volume of air con- C. Increase the pressure limit to 50 cm H2O.
taining 18 g/m3 (content) of water at 37ºC. D. Increase the low-pressure alarm to 35 cm H2O.

A. 18% IIIE1i(1)
B. 37%
142. A nine-year-old, 30-kg girl is being mechanically ven-
C. 41%
tilated with a microprocessor ventilator. The ventilator
D. 43%
settings are as follows:

Chapter 5: Therapeutic Procedures 311

 • mode: SIMV IIIE1i(1)
• SIMV rate: 4 breaths/minute 145. An accumulation of secretions in the airway of a pa-
• inspiratory flow: 12 liters/minute tient who is on a pressure-cycled ventilator operating
• mechanical tidal volume: 450 cc as a continuous mechanical ventilator will result in
• FIO2: 0.50 which situation?
Her spontaneous ventilatory measurements include: A. an increase in the peak system pressure
spontaneous tidal volume: 300 cc B. a decrease in the ventilatory rate
spontaneous rate: 6 breaths/minute C. an increase in tidal volume
D. a decrease in the I:E ratio
Arterial blood-gas data reveal the following:
PO2 90 torr
IIIE1i(1)
PCO2 65 torr
pH 7.22 146. During mechanical ventilation in SIMV and pressure-
HCO 3̄ 26 mEq/L support ventilation modes, a patient has a spontaneous
ventilatory rate of 32 breaths/minute. The ventilator
What ventilator-setting change should the CRT make rate is set at 4 breaths/minute, a tidal volume of 950 cc,
at this time? and a pressure-support level of 5 cm H2O. The pa-
A. Increase the inspiratory time percent. tient’s spontaneous tidal volumes range from 230 cc to
B. Change the mode to controlled ventilation. 290 cc, and he is using accessory ventilatory muscles.
C. Increase the SIMV rate. Arterial blood gases are within the normal range.
D. Decrease the inspiratory flow rate. Which of the following ventilator adjustments might
be appropriate?
IIIE1i(1) A. increasing pressure support to 10 cm H2O
143. An adult patient is receiving mechanical ventilation via B. increasing the preset tidal volume
a volume-cycled ventilator with the following settings: C. changing to pressure-control mode
D. increasing the FIO2
• mode: assist/control
• tidal volume: 800 ml
• ventilatory rate: 14 breaths/minute IIIE1i(1)
• peak flow rate: 20 liters/minute 147. Increasing which of the following ventilator settings
• high-pressure limit: 60 cm H2O would most likely increase oxygenation in a mechani-
• FIO2: 0.40 cally ventilated infant who has respiratory distress
The patient, assisting at a rate of 16 breaths/minute, syndrome?
appears anxious. The high-pressure limit and I:E ratio A. PIP
alarms are sounding. What action should the CRT take B. mean airway pressure
to correct this situation? C. inspiratory flow rate
A. Increase the high-pressure limit to 70 cm H2O. D. inspiratory-expiratory ratio
B. Increase the ventilatory rate to 16 breaths/minute.
C. Increase the peak flow rate to 50 liters/minute.
IIIE1i(1)
D. Increase the FIO2 to 0.50.
148. When 10 cm H2O PEEP is initiated, the patient’s car-
IIIE1i(1) diac output decreases from 7.2 to 4.8 liters/minute, and
his mixed venous PO2 decreases from 43 torr to 35
144. A patient receiving mechanical ventilation via a volume-
torr. Which of the following actions should the CRT
cycled ventilator is experiencing respiratory acidosis.
recommend?
Which action(s) could be instituted by the CRT to cor-
rect this situation? A. Perform an arterial blood-gas analysis to check
the patient’s PaO2.
I. Increase the ventilatory rate.
B. Increase the PEEP to 15 cm H2O to determine
II. Increase the tidal volume.
whether optimal PEEP can be reached.
III. Increase the peak flow rate.
C. Decrease the PEEP to 5 cm H2O, and recheck the
IV. Institute PEEP.
cardiac output and mixed venous PO2.
A. III only D. Decrease the inspiratory time to extend the car-
B. I, II only diac filling time.
C. II, IV only
D. I, II, III only

312 Chapter 5: Therapeutic Procedures

IIIE1i(1) lung transplant. He is hemodynamically stable while
149. A 10-year-old near-drowning victim has been resusci- being mechanically ventilated via a pressure controller
tated at an ocean beach after a 12-minute submersive in the SIMV mode with the following settings:
episode. Twenty-four hours after the incident, the chest • SIMV rate: 8 breaths/minute
radiograph revealed evidence of pulmonary edema. • PEEP: 5 cm H2O
Now, three days later, she remains on a mechanical • tidal volume: 800 cc
ventilator. She has shown signs of neurologic improve- • inspiratory time %: 40%
ment with response to verbal stimuli. Arterial blood • FIO2: 0.60
gases obtained with the patient breathing an FIO2 of
0.40 and receiving 15 cm H2O of PEEP are as follows:
IIIE1i(1)
PO2 165 torr
152. The CRT is called into the patient’s room to assess the
PCO2 35 torr
intermittent occurrence of a ventilator alarm. The
pH 7.44
nurse states that the patient has awakened and breathes
HCO 3̄ 23 mEq/liter
occasionally, but is receiving morphine for pain and
Which of the following modifications should the CRT anxiety every hour. The patient data panel and alarm
recommend? settings display the following information:
A. Decrease the PEEP to 10 cm H2O and maintain • frequency (total): 8 breaths/minute
the FIO2 at 0.40. • ventilator tidal volume: 800 cc
B. Increase the FIO2 to 0.45 and decrease PEEP to • exhaled tidal volume: 720 cc
10 cm H2O. • expired minute ventilation: 5.8 liters/minute
C. Decrease the FIO2 to 0.35 and initiate SIMV. • PIP: 34 cm H2O
D. Discontinue PEEP and increase the FIO2 to 0.50. • high-pressure limit: 40 cm H2O
• high-frequency alarm: 10 breaths/minute
IIIE2c • high minute-ventilation alarm: 7.0 liters/minute
Questions #150 and #151 refer to the same patient. • low minute-ventilation alarm: 5.0 liters/minute
• high/low oxygen alarm: 0.65/0.55
150. Calculate the inspiratory-expiratory ratio of a time-
cycled, pressure-limited infant ventilator delivering a On the basis of this information, the most appropriate
ventilatory rate of 60 breaths/minute with an inspira- action would be to:
tory time of 0.6 second to a neonate who has respira- A. Inspect the patient’s system for a leak.
tory distress syndrome. B. Readjust the alarm settings.
A. 2:1 C. Drain the water from the tubing.
B. 1.5:1 D. Increase the tidal volume setting.
C. 0.67:1
D. 1:1 IIIE1i(3)
153. The lung-transplant patient, still mechanically venti-
IIIE1i(1) lated, is now two days post-op and is beginning to show
151. If this patient’s lung compliance increased, what should signs of organ rejection. The patient is heavily sedated
the CRT do to prevent the development of auto-PEEP? but remains tachypneic and has been changed to the
I. Decrease the inspiratory time. assist/control mode. The VT, ventilatory rate, FIO2, and
II. Reduce the ventilatory rate. PEEP settings remain the same. His most recent arter-
III. Increase the PIP limit. ial blood gas and acid-base results are as follows:
IV. Decrease the inspiratory-expiratory ratio. PO2 105 torr
A. I, II, IV only PCO2 20 torr
B. II, III, IV only pH 7.58
C. I, II only HCO 3̄ 19 mEq/liter
D. II, IV only Based on this information, which of the following rec-
ommendations is the most appropriate?
IIIE1i(1)
A. Add mechanical dead space.
Questions #152 and #153 refer to the same patient. B. Institute an inflation hold.
A 53-year-old male with emphysema secondary to cig- C. Perform an auto-PEEP measurement.
arette smoking is four hours post-operative from a left- D. Decrease the assist/control rate.

Chapter 5: Therapeutic Procedures 313

IIIE1i(1) C. Change to a 28% Venturi mask.
154. Which of the following flow patterns would poten- D. Change to a 3 liters/minute nasal cannula.
tially be most beneficial in ventilating an adult respi-
ratory distress syndrome patient? IIIE2a
158. While caring for a patient receiving oxygen via a non-
A. sine wave flow pattern
rebreathing mask, the CRT observes the reservoir bag
B. accelerating flow pattern
collapsing during inspiration. What action should the
C. decelerating flow pattern
CRT take regarding this situation?
D. square wave flow pattern
A. Administer oxygen via a simple oxygen mask.
IIIE1i(2) B. Obtain a pulse oximeter and assess the patient’s
oxygenation status.
155. A CRT notices a pinhole leak in the disposable ventila-
C. Check the valves in the mask for proper function.
tor circuit after a tubing change on a microprocessor
D. Increase the flow rate to the mask.
ventilator. The exhaled tidal volume is within 5% of the
set tidal volume, and there is a 2 cm H2O difference in
the PIP after the tubing change. Which of the following IIIE2a
actions should the CRT take to correct the problem? 159. A severe COPD patient is receiving oxygen via an air-
entrainment mask at an FIO2 of 0.50. The CRT enters
A. Increase the set tidal volume by 5%. this patient’s room and finds the patient to be confused
B. Replace the ventilator circuit. and lethargic. What should the CRT do at this time?
C. Disconnect the patient and ventilate with 100%
oxygen via a manual resuscitator. A. Initiate a code.
D. Draw a circle around the hole, document the prob- B. Recommend a nasal cannula at 6 liters/min.
lem, and call the manufacturer. C. Recommend a simple mask at 12 liters/min.
D. Recommend lowering the delivered FIO2 to 0.28.
IIIE1i(3)
IIIE2c
156. An 83-kg (IBW) patient is receiving controlled me-
chanical ventilation from a volume ventilator with the 160. A 32-year-old female with myasthenia gravis has been
following settings: intubated and mechanically ventilated for seven days
because of a cholinergic crisis. Extubation appears im-
• VT: 900 cc probable within the next 10 days. The physician asks
• ventilatory rate: 16 breaths/minute for the CRT’s recommendation concerning this pa-
• peak flow rate: 50 liters/minute tient. The CRT should recommend which of the fol-
• FIO2: 0.40 lowing actions?
The PIP is 40 cm H2O, and the static pressure is 36 cm A. administrating of an in-line -2 agonist
H2O. Calculate this patient’s V̇D. B. implementing of more aggressive bronchial-
A. 1.44 liters/minute hygiene therapy
B. 1.66 liters/minute C. performing a tracheotomy
C. 2.93 liters/minute D. initiating permissive hypercapnia
D. 3.20 liters/minute
IIIE2d
IIIE2a 161. The physician asks the CRT to recommend a weaning
method for a 75-year-old, 50-kg female who is being
157. A 70-year-old chronically hypercapnic male with a
mechanically ventilated for pneumonia. She is being
100-pack-per-year history of smoking is admitted to
ventilated in the assist/control mode with the following
the emergency department with shortness of breath
settings:
and tachypnea. He appears mildly confused and is
given oxygen via a 35% Venturi mask. Within minutes, • FIO2: 0.40
his ventilations become increasingly shallow, and he • ventilatory rate: 10 bpm
appears drowsy. An arterial blood gas has been re- • VT : 650 cc
quested. Which of the following actions should the
She has an overall minute ventilation of 9.1 liters/min.
CRT recommend?
While observing the pressure waveform, the CRT
A. Continue to observe the patient until he is less records only four negative pressure deflections per
anxious. minute, each of which are sufficient to initiate a me-
B. Administer a bronchodilator treatment after ob- chanically delivered tidal volume. Her arterial blood-
taining a baseline peak flow. gas data at this time are as follows:

314 Chapter 5: Therapeutic Procedures

 PO2 70 torr PO2: 93 mm Hg
PCO2 42 torr PCO2: 50 mm Hg
pH 7.37 pH: 7.30
HCO 3̄ 22 mEq/L SO2: 94%
B.E. –2 mEq/L
What changes should the CRT recommend to normal-
Which of the following methods should the CRT rec- ize this patient’s PaCO2?
ommend to initiate the weaning process?
A. Increase the ventilatory rate to 12 breaths/minute.
A. pressure-support ventilation B. Increase the ventilatory rate to 15 breaths/minute.
B. T-piece trial C. Increase the tidal volume to 1,200 ml.
C. SIMV with pressure-support ventilation D. Discontinue the PEEP.
D. SIMV with pressure-control ventilation
IIIE2d
IIIE2d 165. Consider the ventilator management of a post-opera-
162. Which of the following ventilatory consideration(s) is tive patient who has undergone uneventful coronary
(are) appropriate when mechanically ventilating a bypass surgery and that of a patient who has acute pul-
COPD patient? monary edema. What differences and/or similarities
I. establishing an inspiratory time that is longer than might exist? Assume that all patient factors and vari-
the expiratory time ables (for example, age, weight, and sex) are equal—
II. setting a tidal volume equivalent to 15 cc/kg of except the clinical condition of these two patients.
ideal body weight I. Both patients would probably be maintained on a
III. maintaining a low PIP high FIO2; that is, greater than 0.60.
IV. instituting PEEP in the range of 10 to 12 cm H2O II. PIP for the pulmonary edema patient would be
A. III only greater than that for the post-operative thoraco-
B. I, IV only tomy patient.
C. I, II, IV only III. Both patients would probably be candidates for a
D. II only PEEP level of approximately 10 cm H2O.
IV. The postoperative thoracotomy patient might ben-
efit more from the sigh mechanism than the pul-
IIIE2d
monary edema patient would.
163. A patient is being weaned from mechanical ventilation
with SIMV at a ventilatory rate of 8 breaths/minute. A. II, IV only
The patient is alert with stable vital signs. Arterial B. II, III only
blood gases reveal: C. I, II, IV only
D. I, II only
PO2: 84 mm Hg
PCO2: 37 mm Hg
pH: 7.42 IIIE2d
166. A PEEP of 10 cm H2O has just been instituted on a pa-
What action should the CRT recommend at this time? tient receiving volume ventilation. What ventilator set-
A. Maintain the present settings. tings might require changing to accommodate the
B. Increase the ventilatory rate to 10 breaths/minute. PEEP?
C. Decrease the ventilatory rate to 6 breaths/minute. I. sensitivity
D. Decrease the ventilatory rate to 2 breaths/minute. II. pressure limit
III. tidal volume
IIIE2d IV. sigh controls
164. A 66-inch (168-cm) tall, adult female weighing 135 lbs
A. I, II, III, IV
is being mechanically ventilated with the following
B. I, II, IV only
settings:
C. II, III only
• mode: control D. I, III, IV only
• tidal volume: 900 ml
• ventilatory rate: 10 breaths/minute IIIE2d
• FIO2: 0.40
167. A patient who has Pneumocystis carinii pneumonia is
• PEEP: 5 cm H2O
receiving mechanical ventilation via the following
An arterial blood-gas analysis reveals: ventilator settings:

Chapter 5: Therapeutic Procedures 315

 • mode: SIMV control mode for 24 hours. An arterial blood-gas
• VT: 900 cc analysis reveals:
• FIO2: 1.0
PO2 62 torr
• SIMV rate: 22 breaths/minute
PCO2 40 torr
• peak inspiratory flow rate: 75 liters/minute
pH 7.50
• PEEP: 20 cm H2O
• inspiratory hold: 0.5 second Which of the following actions should the CRT rec-
• I:E ratio: 1:1 ommend?
His hemodynamic status has deteriorated over the past A. changing to the SIMV mode
several hours, despite positive inotropic agents and af- B. changing to the control mode
terload reduction. Which ventilatory adjustment would C. instituting PEEP
likely improve the patient’s cardiovascular status? D. maintaining the present settings
A. decreasing the inspiratory hold
B. increasing the PEEP IIIE2d
C. applying expiratory retard 171. During an IPPB treatment, the CRT notices the
D. decreasing the flow rate manometer needle swinging to –10 cm H2O with each
patient inspiration. What should the CRT do in this sit-
IIIE2d uation?
168. How would the CRT increase the ventilatory rate on a A. Check for leaks in the circuit.
time-cycled, pressure-limited ventilator that had inde- B. Coach the patient to inhale with greater effort.
pendent inspiratory and expiratory time controls? C. Increase the sensitivity setting on the machine.
I. Increase the inspiratory time. D. Place nose clips on the patient before continuing.
II. Increase the inspiratory-expiratory ratio.
III. Decrease the inspiratory time. IIIE2d
A. III only 172. CPAP by mask is indicated for treatment of all of the
B. II, III only following conditions EXCEPT
C. I, II only A. Post-operative atelectasis in the thoracic surgical
D. I only patient.
B. Refractory hypoxemia in patients who have Pneu-
IIIE2d mocystis carinii pneumonia.
169. A 72-inch tall, 30-year-old male who weighs 176 lbs is re- C. Nocturnal obstructive sleep apnea.
ceiving mechanical ventilation with the following settings: D. Acute hypercapnic respiratory failure.

• mode: SIMV
• FIO2: 0.40 IIIE2d
• tidal volume: 700 ml 173. Which of the following inspiratory flow waveforms
• ventilatory rate: 10 breaths/minute can improve distribution of gas in the lungs and im-
• PEEP: 5 cm H2O prove oxygenation in an ARDS patient who is being
volume-ventilated in the control mode?
Arterial blood gases reveal:
I. sine wave
PO2: 93 mm Hg II. square wave
PCO2: 55 mm Hg III. decelerating wave
pH: 7.25 IV. accelerating wave
SO2: 96%
A. I, II only
What changes should the CRT recommend at this time? B. I, III only
A. Increase the tidal volume to 900 ml. C. II, IV only
B. Increase the PEEP to 10 cm H2O. D. I, III, IV only
C. Decrease the ventilatory rate to 8 breaths/minute.
D. Decrease the FIO2 to 0.30. IIIE2d
174. A 75-kg man is receiving continuous mechanical ven-
IIIE2d tilation following a cardiac arrest. He is not sponta-
170. A COPD patient who has a history of chronic hyper- neously breathing. His current ventilator settings are as
capnia has been mechanically ventilated in the assist- follows:

316 Chapter 5: Therapeutic Procedures

 • mode: control IIIE2d
• tidal volume: 800 cc 177. A 32-week gestational-age infant has been on nasal
• ventilatory rate: 15 breaths/minute CPAP of 8 cm H2O for 36 hours because of moderate
• FIO2: 0.60 hypoxemia. Recent assessment reveals that the baby
The patient’s arterial blood-gas data reveal: now has a decreased WOB. His ventilatory rate is 45
breaths/minute. Arterial blood gases on an FIO2 of
PO2 75 torr 0.30 reveal:
PCO2 30 torr
pH 7.51 PO2 75 torr
HCO 3̄ 23 mEq/liter PCO2 42 torr
B.E. –1 mEq/L pH 7.38
HCO 3̄ 24 mEq/liter
The CRT is asked to recommend changes in mechani- B.E. 0 mEq/L
cal ventilation in response to the arterial blood-gas
data. What should the initial recommendation be? What recommendation should be made at this time?

A. initiating PEEP at 5 cm H2O A. Intubate and mechanically ventilate the patient.

B. decreasing the tidal volume to 650 ml B. Reduce the CPAP to 5 cm H2O.
C. increasing the FIO2 to 0.65 C. Reduce the FIO2 to 0.26.
D. decreasing the ventilatory rate to 12 breaths/minute D. Reduce the CPAP to 2 cm H2O.

IIIE2d IIIE2d
175. A patient who has moderate hypoxemia is receiving 8 178. A comatose 25-year-old, 65-kg drug-overdose victim
cm H2O of continuous flow CPAP at an FIO2 of 0.60. is receiving continuous mechanical ventilation for
The CPAP system has a 3-liter reservoir bag. The CRT acute respiratory failure.
observes the pressure fall to 4 cm H2O during inspira- Current ventilator settings include:
tion and notes that the patient’s WOB has increased.
What should the CRT do at this time? • mode: IMV
• tidal volume: 950 cc
A. Intubate and mechanically ventilate the patient. • ventilatory rate: 8 breaths/minute
B. Increase the CPAP pressure to 10 cm H2O. • FIO2: 0.60
C. Increase the flow rate to the reservoir bag. • PEEP: 5 cm H2O
D. Increase the FIO2 to 0.70.
The patient’s arterial blood-gas and acid-base data are
IIIE2d as follows:
176. A post-laporatomy, 65-year-old COPD patient is re- PO2 58 torr
ceiving volume ventilation in the assist/control mode, PCO2 52 torr
set at a rate of 15 breaths/minute. The patient is alert pH 7.33
but anxious. Her spontaneous ventilatory rate is 20 HCO 3̄ 27 mEq/liter
breaths/minute. Her breath sounds are diminished but B.E. 3 mEq/L
clear. Her arterial blood gas and acid-base status on an
Which of the following modifications should the CRT
FIO2 of 0.30 are as follows:
recommend to normalize the arterial blood-gas data?
PO2 80 torr
A. Change the mode of ventilation to assist/control at
PCO2 34 torr
8 breaths/minute.
pH 7.49
B. Increase the IMV rate to 10 breaths/minute.
HCO 3̄ 25 mEq/liter
C. Increase the FIO2 to 0.70.
B.E. 1 mEq/L
D. Increase the PEEP to 8 cm H2O.
Which of the following actions should the CRT rec-
ommend at this time? IIIE2d
A. instituting SIMV at a ventilatory rate of 12 breaths/ 179. An ARDS patient is receiving volume ventilation. The
minute high-pressure alarm is set at 50 cm H2O. The patient is
B. decreasing the assist/control rate to 12 breaths/ generating a PIP of 45 cm H2O. The patient is receiv-
minute ing an in-line nebulized sympathomimetic drug and is
C. sedating the patient to reduce her anxiety being suctioned PRN. The nurse is complaining that
D. changing to a T-piece operating at an FIO2 of 0.35 the ventilator alarm is buzzing all the time and asks the

Chapter 5: Therapeutic Procedures 317

 CRT “to do something about it.” What should the CRT ments, but to no avail. Which of the following might
do at this time? be appropriate at this time?
A. Increase the pressure limit to 60 cm H2O. A. nebulized metaproterenol
B. Decrease the inspiratory flow rate. B. I.V. midazolam
C. Decrease the tidal volume. C. inhaled beclomethasone
D. Inform her that no ventilator changes are indicated. D. nebulized racemic epinephrine

IIIE2d IIIE2f
180. Table 5-7 shows optimal PEEP trial data obtained from 183. A mechanically ventilated patient is being evaluated for
a patient who is receiving continuous mechanical ven- weaning. The following ventilatory data were obtained:
tilation for ventilatory failure.
• maximum inspiratory pressure: –25 cm H2O
• vital capacity: 15 ml/kg
Table 5-7: Optimum PEEP trial data
• spontaneous tidal volume: 3 ml/kg
Static Blood • spontaneous ventilatory rate: 20 breaths/minute
PEEP PaO2 Compliance Pressure
What should the CRT recommend at this time?
Trial (cm H2O) (torr) (ml/cm H2O) (torr)
A. Delay weaning until the spontaneous tidal volume
1 0 55 20 125/90 is at least 10 ml/kg.
2 4 65 24 123/90
B. Institute controlled mechanical ventilation.
3 8 75 28 120/80
C. Delay weaning until the spontaneous ventilatory
4 12 81 26 110/80
rate decreases to at least 14 breaths/minute.
D. Institute weaning procedures.
Which PEEP level represents the optimal PEEP level?
IIIE2f
A. 0 cm H2O
B. 4 cm H2O 184. The following data were obtained from a 65-kg patient
C. 8 cm H2O who is being weaned from IMV:
D. 12 cm H2O 9 A.M. DATA

IIIE2d • mode: IMV

• IMV rate: 5 breaths/minute
181. A 15-year-old, 60-kg male is admitted to the emer- • mechanical tidal volume: 500 cc
gency department following a severe head injury. • spontaneous ventilatory rate: 14 breaths/minute
While awaiting transport to another hospital, the pa- • spontaneous tidal volume: 500 cc
tient is receiving pressure-cycled ventilation on an • MIP: –28 cm H2O
FIO2 of 1.0. The ventilator is set at 18 cm H2O and is • heart rate: 90 beats/minute
delivering a VT of about 700 ml. Which of the follow-
ing factors would cause a decrease in the delivered 9:45 A.M. DATA
tidal volume if the PIP remained at 18 cm H2O?
• mode: T-piece spontaneous ventilation
I. increased airway secretions • FIO2: 0.40
II. parasympathetic stimulation of the tracheobronchial • spontaneous ventilatory rate: 26 breaths/minute
tree • spontaneous tidal volume: 350 cc
III. decreased inspiratory flow rate • MIP: –28 cm H2O
IV. intravenous fluid overload • heart rate: 118 beats/minute
A. I, II only Based on these two sets of data, what would be the ap-
B. I, II, IV only propriate recommendation?
C. II, III, IV only
D. I, II, III only A. Increase the FIO2 to 0.50.
B. Initiate 8 cm H2O of CPAP at an FIO2 of 0.40.
IIIE2e C. Initiate IPPB Q2h.
D. Return the patient to IMV at the previous settings.
182. A COPD patient is receiving assist/control mechanical
ventilation for an acute exacerbation of her lung dis-
ease. The patient’s breathing efforts and the mandatory IIIE2f
breaths delivered by the ventilator are asynchronous. 185. A patient who has been mechanically ventilated in the
The CRT has made a variety of mechanical adjust- assist/control mode for 72 hours following a blunt chest

318 Chapter 5: Therapeutic Procedures

 injury is prescribed to receive a heated aerosol Briggs A. Breathe rapidly and deeply.
adaptor for 10 minutes to initiate weaning. After five B. Breathe through the nose slowly.
minutes, the patient exhibits tachypnea, tachycardia, C. Breathe normally through the mouth.
and increased blood pressure. Which of the following D. Breathe slowly and deeply with an inspiratory hold.
recommendations are appropriate at this time?
A. Continue Briggs adaptor weaning as ordered for IIIE2h
an additional five minutes. 190. Continuous high-volume aerosol therapy via an ultra-
B. Reinstitute mechanical ventilation by using SIMV. sonic nebulizer is ordered to promote bronchial hygiene
C. Reinstitute mechanical ventilation by using CPAP. in a patient who has thick secretions. After several hours,
D. Increase the flow rate delivered by the heated neb- the patient complains about “wearing a mask all the time”
ulizer before continuing the weaning process. and states that he does not wish to continue with the treat-
ment. What should the CRT recommend in this situation?
IIIE2f A. changing the treatment to 30 minutes QID
186. A 176-lb adult male is receiving continuous mechani- B. discontinuing the treatment
cal ventilation in the assist-control mode. Which of the C. changing to a large-volume jet nebulizer
following data suggest that the patient might be ready D. asking the physician to discuss the purpose of the
to be weaned from the ventilator? treatment with the patient
A. a spontaneous ventilatory rate of 27 breaths/minute
B. a maximum inspiratory pressure of –25 cm H2O IIIE2i
C. Q̇ S/Q̇ T of 0.34 191. An adult male asthmatic is receiving 0.25 ml of a 0.5% so-
D. spontaneous tidal volume of 250 ml lution of Proventil (albuterol) with 2.5 ml of a 0.9% saline
via a hand-held nebulizer QID. His wheezing diminishes
IIIE2f but does not completely clear following the treatment.
What should the CRT recommend in this situation?
187. A post-operative thoracotomy patient who is receiving
assist/control ventilation in the recovery room begins A. changing to a 1% solution of Proventil
to emerge from anesthesia. As the patient progres- B. changing to Alupent via an MDI
sively becomes more alert, what intervention should C. increasing the frequency of the therapy to every
the CRT recommend at this time? two hours
D. increasing the dose of the Proventil to 0.5 ml
A. extubation
B. weaning from mechanical ventilation
C. an arterial blood-gas puncture IIIE2i
D. removal of the chest tubes 192. A patient who has asthma is receiving 0.3 ml of
metaproterenol diluted with 2 ml of normal saline via
IIIE2g a small-volume nebulizer. While assessing the patient
during the treatment, the CRT observes the patient
188. A 57-year-old patient enters the hospital complaining
trembling and experiencing tachycardia. What should
of a chronic cough that produces large amounts of
the CRT do at this time?
foul-smelling mucus. The patient is diagnosed as hav-
ing bronchiectasis, for which aerosolized metapro- A. Stop the nebulization treatment and administer
terenol has been ordered QID. In addition to this two puffs of metaproterenol via an MDI.
medication, what other treatment should the CRT rec- B. Encourage the patient to breathe less rapidly.
ommend for the care plan? C. Reduce the dosage of metaproterenol to 0.2 ml in
2 ml of normal saline.
A. bronchopulmonary drainage to follow the metapro-
D. Increase the oxygen flow rate used to operate the
terenol
small-volume nebulizer.
B. nebulized acetylcysteine to follow the metapro-
terenol
C. continuous administration of aerosolized saline IIIE2j
via an ultrasonic nebulizer 193. A chest-trauma patient is having a pneumothorax drained
D. nasal CPAP applied at night via a Heimlich valve. Upon physical examination of the
chest, however, a pleural effusion has been discovered.
IIIE2g What action should be taken by the CRT at this time?
189. While administering a small-volume nebulizer treat- A. Maintain intrapleural drainage with the Heimlich
ment, what breathing-pattern instructions are appro- valve.
priate to give to the patient? B. Replace the Heimlich valve with a thoracostomy tube.

Chapter 5: Therapeutic Procedures 319

 C. Maintain the Heimlich valve, and aspirate the A. I, III only
pleural effusion with a large syringe. B. II, IV only
D. Aspirate the intrapleural air with a syringe, and C. I, IV only
drain the pleural effusion with a thoracostomy tube. D. I, II, IV only

IIIE3 IIIE3
194. The physician has just determined airway responsive- 198. A 60-year-old patient who has moderate COPD com-
ness to bronchodilator therapy in a COPD patient. He plains to his physician about experiencing increased
asks the CRT to recommend a bronchodilator for long- dyspnea. The patient’s mucus production is minimal.
term use. Which of the following bronchodilators Auscultation of the patient’s chest indicates poly-
should the CRT recommend for this patient? phonic wheezing during exhalation. Which of the fol-
lowing medications would be most appropriate for the
A. ipratropium bromide CRT to recommend for the patient at this time?
B. metaproterenol sulfate
C. albuterol sulfate A. zarfirlukast
D. bitolteral sulfate B. beclomethasone
C. nedocromil
D. ipratropium bromide
IIIE3
195. The CRT notices that a mechanically ventilated patient IIIE3
in the assist-control mode is breathing asynchronously
199. The CRT receives an order to administer n-acetylcys-
with the ventilator. Assessment of the patient reveals
teine and isoproterenol concurrently via a small-
correct ET tube placement, no pneumothorax, and no
volume nebulizer to a cystic fibrosis patient. The phar-
secretions. Additionally, the sensitivity setting and the
macologic order reads as follows:
inspiratory flow control are appropriately set. What
should the CRT recommend at this time? Nebulize 5.0 cc of 10% n-acetylcysteine with
0.05% isoproterenol.
I. Decrease the pressure limit.
II. Administer Versed. What should the CRT do at this time?
III. Administer Pavulon.
A. Administer the treatment as ordered.
IV. Increase the respiratory rate.
B. Use an ultrasonic nebulizer instead of a small-
A. II, III only volume nebulizer.
B. I, IV only C. Withhold the treatment, because the dose of iso-
C. II, III, IV only proterenol is too large.
D. I, II, III only D. Withhold the treatment, because the dose of the
n-acetylcysteine is too small.
IIIE3
196. The CRT is attempting to perform a non-emergency IIIE3
endotracheal intubation on a patient. The patient is 200. If nebulized Mucomyst is ordered for an asthmatic pa-
restless and combative. What should the CRT recom- tient, what other medication(s) should be concomi-
mend at this time to make the procedure more tolera- tantly administered?
ble for the patient? I. Neo-Synephrine
A. Administer 100% oxygen via a manual resuscitator. II. cromolyn sodium
B. Have the patient sedated. III. an antihistamine
C. Recommend neuromuscular blocking agents. IV. metaproterenol sulfate
D. Intubate the patient in a semi-Fowler position. A. I, II only
B. II, IV only
IIIE3 C. III only
197. All isolation procedures, other than standard precau- D. IV only
tions, require the wearing of gloves and gowns by
health-care personnel EXCEPT IIIE3
201. Which of the following medications will most likely
I. contact precautions.
cause the highest level of tachycardia?
II. airborne precautions.
III. enteric precautions. A. albuterol
IV. droplet precautions. B. terbutaline

320 Chapter 5: Therapeutic Procedures

 C. metaproterenol A. carefully roll the patient on his side and adminis-
D. isoproterenol ter four sharp back blows.
B. turn the patient’s head to the side and finger-
IIIE3 sweep the mouth.
202. Which medication is indicated for the relief of nasal C. attempt to open the airway with the jaw-thrust
congestion? maneuver.
D. perform the Heimlich maneuver.
A. beta-one antagonist
B. cholinergic antagonist IIIF1
C. alpha-one antagonist
207. The CRT enters the room of a 54-year-old patient in
D. alpha-one agonist
the neurologic ICU. She observes that the patient,
whose neck is in traction resulting from an automobile
IIIE3 accident, is not breathing. Which of the following ac-
203. While receiving 3% saline via an ultrasonic nebulizer tions is most appropriate at this time?
to induce sputum, a patient becomes dyspneic and be-
gins to wheeze. Which of the following actions is ap- A. Perform endotracheal intubation.
propriate based on this patient’s response to the B. Establish an airway by hyperextending the pa-
therapy? tient’s head and neck and perform mouth-to-valve
mask ventilation.
A. Discontinue the treatment and induce the sputum C. Insert an oropharyngeal airway and apply bag-
via IPPB. mask ventilation with 100% oxygen.
B. Continue the treatment as ordered after reassuring D. Employ the jaw thrust maneuver to establish an
the patient. airway.
C. Suggest nebulized 0.45% saline in the ultrasonic
nebulizer. IIIF1
D. Suggest administering a sympathomimetic bron-
208. Which conditions can be considered complications of
chodilator before continuing the treatment.
closed-chest cardiac massage?
IIIF1 I. fat embolization
204. The CRT has entered a patient’s room and sees the pa- II. pneumoperitoneum
tient slumped down in a chair. After determining unre- III. fractured ribs
sponsiveness, what should the CRT do? IV. hepatic laceration
V. cardiac contusions
A. Call for help.
B. Feel for a pulse. A. I, IV only
C. Determine breathlesssness. B. III, V only
D. Establish an airway. C. II, III, V only
D. I, II, III, IV, V
IIIF1
IIIF1
205. Which statement describes the appropriate depth of
external cardiac compressions? 209. Following an emergency tracheostomy, the patient expe-
riences a cardiac arrest. The CRT is preparing to manu-
A. Initially, compress the sternum 1 1/2 to 2 inches ally ventilate this patient. Upon auscultation, the CRT
and maintain that pattern. notes significantly reduced breath sounds on the patient’s
B. Initially, compress the sternum 1 1/2 inches and right side, compared with those on the left. Which of the
gradually increase the depth to 2 inches. following conditions could be the cause of this situation?
C. The depth of compressions should be maintained
at 2 inches to achieve an effective cardiac output. I. A right-sided pneumothorax has developed.
D. Initially, compress to a depth of 2 to 2 1/2 inches; II. Inadequate volume is being delivered by the man-
then increase the depth by one-third during resus- ual resuscitator.
citation. III. The tube has slipped into the right mainstem
bronchus.
IV. A cuff leak around the tube has occurred.
IIIF1
206. While making two attempts to establish an airway by A. I only
using the chin-lift procedure, the CRT observes no B. I, III only
chest movement as ventilation is attempted. The CRT C. II, III, IV only
should then D. I, II, III only

Chapter 5: Therapeutic Procedures 321

IIIF1 A. Increase the FIO2 by using a partial rebreathing
210. Upon entering a patient’s room to perform chest mask.
physiotherapy, a CRT discovers that the patient is un- B. Cardiovert the patient.
conscious. What should be the correct sequence of ac- C. Administer 1 to 1.5 mg/kg I.V. of lidocaine.
tions conducted by the CRT? D. Administer 10 to 20 µg/kg/min of dopamine I.V.

A. Call for help, establish the airway, establish unre- IIIF2

sponsiveness, establish breathlessness, and begin
214. A patient who is displaying ventricular fibrillation has
ventilation.
been treated with defibrillation, epinephrine, and
B. Establish unresponsiveness, establish breathless-
lidocaine in an attempt to convert the ventricular fib-
ness, call for help, establish the airway, and begin
rillation to ventricular tachycardia. None of these in-
ventilation.
terventions has worked. What should the CRT attempt
C. Establish breathlessness, establish unresponsive-
to do next?
ness, call for help, establish the airway, and begin
ventilation. A. Administer 2.5 to 5.0 mg/kg of verapamil I.V.
D. Establish unresponsiveness, call for help, estab- B. Administer 0.25 mg/kg of diltiazem I.V.
lish the airway, establish breathlessness, and be- C. Administer 5 mg/kg of bretylium I.V.
gin ventilation. D. Cardiovert the patient.

IIIF1 IIIF2
211. The CRT has just given an apneic adult victim two 215. In which of the following situations is defibrillation in-
slow, mouth-to-mouth ventilations. He immediately dicated?
palpates the carotid artery and perceives a pulse. What
would be the most appropriate action taken by the I. asystole
CRT at this time? II. pulseless ventricular tachycardia
III. pulseless electrical activity
A. Perform 15 external cardiac compressions. IV. polymorphic ventricular tachycardia
B. Continue performing mouth-to-mouth ventila-
tions at a rate of 12 breaths/minute. A. II, IV only
C. Assess cerebral circulation by noting the pupil status. B. II, III only
D. Check the airway for the presence of a foreign object. C. I, III only
D. II, III, IV only
IIIF2
212. For which of the following dysrhythmias is cardiover- IIIF2
sion applied? 216. Which action(s) is (are) considered a vagal maneuver(s)?
I. ventricular fibrillation I. facial immersion in ice water
II. atrial fibrillation II. eyeball pressure
III. atrial flutter III. circumferential digital sweep of the anus
IV. ventricular tachycardia IV. carotid sinus massage
A. I, II only A. IV only
B. II, III only B. II, III only
C. I, IV only C. I, II, IV only
D. II, III, IV only D. I, II, III, IV

IIIF2 IIIF2
213. A hemodynamically unstable, cardiac-monitored patient 217. Which medication(s) increase(s) the force of myocar-
who is receiving an FIO2 of 0.40 via an air-entrainment dial contractility?
mask has the following signs and symptoms:
I. calcium chloride
• shortness of breath II. verapamil
• hypotension III. adenosine
• signs of congestive heart failure IV. bretylium
• decreased level of consciousness
A. I only
• persistent chest pain
B. II, III only
The patient’s heart rate is 160 beats/min. What action C. III, IV only
should the CRT take at this time? D. I, II only

322 Chapter 5: Therapeutic Procedures

IIIF2 C. I, III, IV only
218. While performing incentive spirometry in the presence D. I, II, IV only
of a CRT, a patient experiences an acute, piercing chest
pain on the right hemithorax. Rapid assessment of the IIIF4
patient suggests a pneumothorax. What action should 222. Immediately upon delivery, a newborn is dried and
be taken by the CRT? suctioned to stimulate respirations. The infant remains
apneic after these procedures, however. Which of the
A. Administer a -2 agonist via a small-volume nebu-
following actions are appropriate at this time?
lizer.
B. Administer an IPPB treatment to re-expand the lungs. I. administering free-flow oxygen
C. Perform endotracheal intubation. II. rubbing the infant’s back
D. Administer as high an FIO2 as possible. III. placing a cold compress on the infant’s back
IV. slapping the soles of the infant’s feet
IIIF3
A. II, IV only
219. The CRT is about to intubate a pediatric patient. How B. I, III, only
would the CRT determine the proper length of the C. I, II, IV only
laryngoscope blade to use? D. I, II, III, IV
A. holding the blade next to the patient’s face and seeing
it reach from the patient’s lips to the thyroid cartilage IIIG1b
B. placing the blade in the patient’s palm to determine 223. The CRT is preparing to assist a physician with perform-
whether it extends from the thumb to the little finger ing a thoracentesis. How should the patient be positioned?
C. holding the blade against the side of the infant’s
face to see whether the blade extends from the lips A. Trendelenburg position
to the tragus of the ear B. reverse Trendelenburg position
D. using the standard size laryngoscope blade C. sitting upright while leaning slightly forward
D. semi-Fowler position
IIIF3
QUESTIONS #224 AND #225 REFER TO THE SAME
220. What is the minimum tidal volume that is acceptable
SITUATION.
for a manual resuscitator used for pediatric bag-mask
ventilation? IIIG1d
A. 550 ml During a code situation, the CRT looks at the ECG
B. 500 ml monitor and sees the tracing shown in Figure 5-5.
C. 450 ml 224. Which of the following actions should the CRT rec-
D. 400 ml ommend to the physician at this time?
IIIF4 A. defibrillation
221. After ventilating a newborn for 30 seconds into a resus- B. cardioversion
citative procedure, the CRT prepares to check the infant’s C. a lidocaine drip
heart rate. How should the CRT evaluate the heart rate? D. intracardiac injection of epinephrine

I. Palpate the radial artery. IIIG1d

II. Listen to the apical beat with a stethoscope.
225. A patient enters the emergency department with a
III. Palpate the umbilical pulse.
blood pressure of 160/100 torr and a heart rate of 120
IV. Palpate the carotid artery.
bpm. The patient is diaphoretic and complains of chest
A. I, III only pains and crushing sensations in the chest. Which of the
B. II, III only following interventions are appropriate at this time?

Figure 5-5: ECG tracing.

Chapter 5: Therapeutic Procedures 323

 I. oxygen at 4 lpm C. 160 beats/min.
II. I.V. morphine D. 215 beats/min.
III. I.V. adenosine
IV. I.V. bretylium IIIG2a
A. I, II only 230. Which of the following factors are considered critical
B. III, IV only elements for achieving successful abstinence from cig-
C. I, II, III only arette smoking?
D. I, II, IV only I. identifying moments or times when smoking con-
tributes to a negative outcome
IIIG2a
II. maintaining an exercise program
226. Which of the following evaluations are useful for as- III. establishing a date for quitting
sessing patient outcome following a pulmonary reha- IV. receiving follow-up input from health-care per-
bilitation program? sonnel
I. frequency and duration of hospitalizations A. I, II only
II. weight gain or weight loss B. III, IV only
III. amount and quality of sputum production C. I, III, IV only
IV. flexibility and posture D. I, II, III, IV
A. I, IV only
B. II, III only IIIG2a
C. I, III, IV only 231. What is the purpose of a transdermal nicotine patch?
D. I, II, III, IV
A. A nicotine patch alone produces high rates of
IIIG2a smoking cessation.
B. The patch can reduce the early-morning nicotine
227. Why should a patient undergo exercise assessment be-
craving.
fore starting a pulmonary rehabilitation program?
C. A nicotine patch achieves a blood nicotine level
I. to determine whether supplemental oxygen will equivalent to the pleasure-inducing level.
be necessary during the program D. A nicotine patch eliminates the need for counseling.
II. to ascertain the appropriate exercise training program
III. to assess the patient’s cardiac function IIIG2c
IV. to evaluate the patient’s pulmonary status 232. The CRT is assigned to perform monthly service to a
A. I, II only patient who is receiving home oxygen from an oxygen
B. III, IV only concentrator. Which of the following services need to
C. I, III, IV only be provided each month as routine maintenance?
D. I, II, III, IV I. Clean or replace filters.
II. Swab the external components of the concentra-
IIIG2a
tion with a 70% ethyl alcohol solution.
228. What is the appropriate amount of time to devote to III. Analyze the concentrator’s FIO2.
upper-body endurance during the physical conditioning IV. Check the concentrator’s alarm systems.
component of a pulmonary rehabilitation program?
A. I, III only
A. 10 minutes B. II, IV only
B. 15 minutes C. I, III, IV only
C. 20 minutes D. I, II, III, IV
D. 45 minutes
IIIG2c
IIIG2a
233. The CRT notices that a calibrated oxygen analyzer
229. A COPD patient exercises at home by walking for 12 connected to an oxygen concentrator is set at 5
minutes. Calculate this patient’s target heart rate based liters/min. in a patient’s home and reads 80%. What
on the following data: action does the CRT need to take at this time?
peak heart rate: 135 beats/min. A. Increase the liter flow to 10 liters/min.
resting heart rate: 80 beats/min. B. Decrease the liter flow to 3 liters/min.
A. 113 beats/min. C. Make sure that the concentrator is plugged in.
B. 135 beats/min. D. Replace the concentrator.

324 Chapter 5: Therapeutic Procedures

IIIG2c Two puffs of Ventolin via MDI, QID, immediately
234. A COPD patient is about to be discharged from the followed by two puffs of Atrovent via MDI, QID.
hospital while still in need of mechanical ventilation. The discharge planner questions the sequencing of
What must the CRT evaluate in the home to determine these MDIs. What response should the CRT offer to
the capability to support the patient’s mechanical ven- resolve this issue?
tilatory needs?
A. The sequence of these two MDIs makes no dif-
A. that the home complies with modern plumbing ference in the patient’s therapeutic response.
codes B. Inhalation from the Ventolin MDI must precede
B. that the home has a central air-conditioning system that of the Atrovent MDI.
C. that the power supply to the home is reliable C. Inhalation from the Atrovent MDI must precede
D. that the family has a cellular phone that of the Ventolin MDI.
D. The physician needs to be contacted to review the
IIIG2c appropriate sequencing of the MDIs.
235. A COPD patient is about to be discharged from the
hospital. The physician has ordered the following
bronchodilator protocol:

Chapter 5: Therapeutic Procedures 325

 STOP
You have completed the 125 questions referring to the matrix sections IIIE, IIIF, and IIIG. Use the Entry-Level Ex-
amination Matrix Scoring Form for Therapeutic Procedures, sections IIIE, IIIF, and IIIG in Table 5-8, to evaluate
your performance. Then refer to the Therapeutic Procedures portion of the NBRC Entry-Level Examination Matrix
in Table 5-9 to continue your assessment.
Table 5-8: Therapeutic procedures: entry-level examination matrix scoring form

Therapeutic
Entry-Level Examination Therapeutic Procedures Therapeutic Procedures Procedures
Content Area Item Number Items Answered Correctly Content Area Score

IIIE1. Modify and recommend 111, 112, 113, 114, 115, 116,
modifications in therapeutics 117, 118, 119, 120, 121, 122,
and recommend . 123, 124, 125, 126, 127, 128,
pharmacologic agents 129, 130, 131, 132, 133, 134, __  100 = ____%
135, 136, 137, 138, 139, 140, 46
141, 142, 143, 144, 145, 146,
147, 148, 149, 150, 151, 152,
153, 154, 155, 156

IIIE2. Recommend modifications based 157, 158, 159, 160, 161, 162,
on patient response. 163, 164, 165, 166, 167, 168,
169, 170, 171, 172, 173, 174,
175, 176, 177, 178, 179, 180, __  100 = ____%
181, 182, 183, 184, 185, 186, 37
187, 188, 189, 190, 191, 192, __  100 = ____%
___
193 125

IIIE3. Recommend pharmacologic 194, 195, 196, 197, 198, 199, __  100 = ____%
agents. 200, 201, 202, 203 10

IIIF1–4. Treat cardiopulmonary collapse 204, 205, 206, 207, 208, 209,
according to BLS, ACLS, PALS, 210, 211, 212, 213, 214, 215, __  100 = ____%
and NRP. 216, 217, 218, 219, 220, 221, 19
222

IIIG. Assist the physician with 223, 224, 225 _  100 = ____%
performing special procedures. 3

IIIG2. Initiate and conduct pulmonary 226, 227, 228, 229, 230, 231, __  100 = ____%
rehabilitation and home care. 232, 233, 234, 235 10

326 Chapter 5: Therapeutic Procedures

Table 5-9: NBRC Certification Examination for Entry-Level Certified Respiratory Therapists (CRTs)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
Content Outline—Effective July 1999

IS

IS
N

N
alter position of patient, alter duration

N
of treatment and techniques, coordinate
III. Initiate, Conduct, and sequence of therapies, alter equipment
Modify Prescribed used and PEP therapy] x
g. modify artificial airways management:
Therapeutic Procedures (1) alter endotracheal or tracheostomy
SETTING: In any patient care tube position, change endotracheal
setting, the respiratory therapist or tracheostomy tube x
communicates relevant informa- (2) change type of humidification
tion to members of the health- equipment x
care team, maintains patient (3) initiate suctioning x
records, initiates, conducts, and (4) inflate and deflate the cuff x
modifies prescribed therapeutic h. modify suctioning:
procedures to achieve the de- (1) alter frequency and duration of
sired objectives and assists the suctioning x
physician with rehabilitation and (2) change size and type of catheter x
home care. (3) alter negative pressure x
(4) instill irrigating solutions x
i. modify mechanical ventilation:
E. Modify and recommend modifications (1) adjust ventilator settings [e.g.,
in therapeutics and recommend ventilatory mode, tidal volume, FiO2,
pharmacologic agents. 3* 12 17 inspiratory plateau, PEEP and
1. Make necessary modifications in therapeutic CPAP levels, pressure support and
procedures based on patient response: pressure control levels, non-invasive
a. terminate treatment based on patient’s positive pressure, alarm settings]
response to therapy being administered (2) change patient breathing circuitry,
b. modify IPPB: change type of ventilator x
(1) adjust sensitivity, flow, volume, (3) change mechanical dead space x
pressure, FiO2 x** j. modify weaning procedures
(2) adjust expiratory retard x 2. Recommend the following modifications
(3) change patient—machine interface in the respiratory care plan based on
[e.g., mouthpiece, mask] x patient response:
c. modify incentive breathing devices [e.g., a. change FiO2 and oxygen flow
increase or decrease incentive goals] x b. change mechanical dead space
d. modify aerosol therapy: c. use or change artificial airway [e.g.,
(1) modify patient breathing pattern x endotracheal tube, tracheostomy]
(2) change type of equipment, change d. change ventilatory techniques [e.g.,
aerosol output x tidal volume, respiratory rate, ventilatory
(3) change dilution of medication, mode, inspiratory effort (sensitivity),
adjust temperature of the aerosol x PEEP/CPAP, mean airway pressure,
e. modify oxygen therapy: pressure support, inverse-ratio
(1) change mode of administration, ventilation, non-invasive positive
adjust flow, and FiO2 x pressure]
(2) set up or change an O2 blender x e. use muscle relaxant(s) and/or
(3) set up an O2 concentrator or liquid sedative(s)
O2 system x f. wean or change weaning procedures
f. modify bronchial hygiene therapy [e.g., and extubation

*The number in each column is the number of item in that content area and the cognitive level contained in each
examination. For example, in category I.A., two items will be asked at the recall level, three items at the application level,
and no items at the analysis level. The items could be asked relative to any tasks listed (1–2) under category I.A.
**Note: An “x” denotes the examination does NOT contain items for the given task at the cognitive level indicated in the
respective column (Recall, Application, and Analysis).

Chapter 5: Therapeutic Procedures 327

Table 5-9: (Cont.)

APP

APP
ANA

ANA
LIC

LIC
REC

REC
ATI

ATI
LYS

LYS
ALL

ALL
ON

ON
IS

IS
N

N
N

N
g. institute bronchopulmonary hygiene a. bronchoscopy x
procedures [e.g., PEP, IS, IPV, CPT] b. thoracentesis x
h. modify treatments based on patient c. tracheostomy x
response [e.g., change duration of d. cardioversion x
therapy, change position] e. intubation x
i. change aerosol drug dosage or 2. Initiate and conduct pulmonary rehabilitation
concentration and home care within the prescription:
j. insert chest tube a. explain planned therapy and goals to
3. Recommend use of pharmacologic agents patient in understandable terms to
[e.g., anti-infectives, anti-inflammatories, achieve optimal therapeutic outcome,
bronchodilators, cardiac agents, diuretics, counsel patient and family concerning
mucolytics/proteolytics, narcotics, smoking cessation, disease
sedatives, surfactants, vasoactive agents] management x
F. Treat cardiopulmonary collapse according b. assure safety and infection control x
to the following protocols. 2 4 0 c. modify respiratory care procedures for
1. BCLS x use in the home x
2. ACLS x d. conduct patient education and
3. PALS x disease management programs x
4. NRP x
TOTALS 36 72 32
G. Assist the physician, initiate and conduct
pulmonary rehabilitation and home care. 2 3 0
1. Act as an assistant to the physician,
performing special procedures that include
the following:

328 Chapter 5: Therapeutic Procedures

 Matrix Categories
1. IIIA1 49. IIIB1d 97. IIID5 145. IIIE1i(1)
2. IIIA1 50. IIIB1e 98. IIID6 146. IIIE1i(1)
3. IIIA1 51. IIIB2a 99. IIID7 147. IIIE1i(1)
4. IIIA1 52. IIIB2a 100. IIID7 148. IIIE1i(1)
5. IIIA1 53. IIIB2a 101. IIID7 149. IIIE1i(1)
6. IIIA1 54. IIIB2a 102. IIID7 150. IIIE2c
7. IIIA1 55. IIIB2b 103. IIID7 151. IIIE1i(1)
8. IIIA1 56. IIIB2b 104. IIID7 152. IIIE1i(1)
9. IIIA1b(4) 57. IIIB2b 105. IIID7 153. IIIE1i(3)
10. IIIA2a 58. IIIB2c 106. IIID7 154. IIIE1i(1)
11. IIIA2a 59. IIIB2c 107. IIID8 155. IIIE1i(2)
12. IIIA2a 60. IIIB2d 108. IIID8 156. IIIE1i(3)
13. IIIA2b(1) 61. IIIB2d 109. IIID9 157. IIIE2a
14. IIIA2b(1) 62. IIIB2d 110. IIID10 158. IIIE2a
15. IIIA2b(1) 63. IIIC1a 111. IIIE1c 159. IIIE2a
16. IIIA2b(1) 64. IIIC1a 112. IIIE1d(2) 160. IIIE2c
17. IIIA2b(2) 65. IIIC1b 113. IIIE1d(2) 161. IIIE2c
18. IIIA2b(2) 66. IIIC1b 114. IIIE1f 162. IIIE2d
19. IIIA2b(3) 67. IIIC1b 115. IIIE1i(1) 163. IIIE2d
20. IIIA2b(3) 68. IIIC1b 116. IIIE1i(1) 164. IIIE2d
21. IIIA2b(4) 69. IIIC1d 117. IIIE1i(1) 165. IIIE2d
22. IIIA2b(4) 70. IIIC1d 118. IIIE1i(1) 166. IIIE2d
23. IIIA2b(5) 71. IIIC1d 119. IIIE1i(1) 167. IIIE2d
24. IIIA2b(5) 72. IIIC1d 120. IIIE1a 168. IIIE2d
25. IIIA2c 73. IIIC1d 121. IIIE1a 169. IIIE2d
26. IIIA2c 74. IIIC1d 122. IIIE1a 170. IIIE2d
27. IIIA2d 75. IIIC1d 123. IIIE1a 171. IIIE2d
28. IIIA2e 76. IIIC1d 124. IIIE1a 172. IIIE2d
29. IIIA2e 77. IIIC1d 125. IIIE1b(1) 173. IIIE2d
30. IIIA2f 78. IIIC1f 126. IIIE1b(1) 174. IIIE2d
31. IIIA2f 79. IIIC1b 127. IIIE1c 175. IIIE2d
32. IIIA2f 80. IIIC1g 128. IIIE1c 176. IIIE2d
33. IIIA3 81. IIIC1g 129. IIIE1d(3) 177. IIIE2d
34. IIIA3 82. IIIC1h 130. IIIE1e(1) 178. IIIE2d
35. IIIA3 83. IIIC2a 131. IIIE1e(1) 179. IIIE2d
36. IIIA3 84. IIIC2b 132. IIIE1e(1) 180. IIIE2d
37. IIIA3 85. IIIC2b 133. IIIE1e(1) 181. IIIE2d
38. IIIA3 86. IIIC2b 134. IIIE1e(3) 182. IIIE2e
39. IIIA3 87. IIIC2c 135. IIIE1e(3) 183. IIIE2f
40. IIIA3 88. IIID1 136. IIIE1f 184. IIIE2f
41. IIIB1a 89. IIID2 137. IIIE1g(1) 185. IIIE2f
42. IIIB1a 90. IIID2 138. IIIE1g(2) 186. IIIE2f
43. IIIB1a 91. IIID2 139. IIIE1g(3) 187. IIIE2f
44. IIIB1a 92. IIID2 140. IIIE1h(3) 188. IIIE2g
45. IIIB1a 93. IIID3 141. IIIE1i(1) 189. IIIE2g
46. IIIB1a 94. IIID4 142. IIIE1i(1) 190. IIIE2h
47. IIIB1b 95. IIID4 143. IIIE1i(1) 191. IIIE2i
48. IIIE3 96. IIID5 144. IIIE1i(1) 192. IIIE2i

Chapter 5: Therapeutic Procedures 329

193. IIIE2j 204. IIIF1 215. IIIF2 226. IIIG2a
194. IIIE3 205. IIIF1 216. IIIF2 227. IIIG2a
195. IIIE3 206. IIIF1 217. IIIF2 228. IIIG2a
196. IIIE3 207. IIIF1 218. IIIF2 229. IIIG2a
197. IIIE3 208. IIIF1 219. IIIF3 230. IIIG2a
198. IIIE3 209. IIIF1 220. IIIF3 231. IIIG2a
199. IIIE3 210. IIIF1 221. IIIF4 232. IIIG2c
200. IIIE3 211. IIIF1 222. IIIF4 233. IIIG2c
201. IIIE3 212. IIIF2 223. IIIG1b 234. IIIG2c
202. IIIE3 213. IIIF2 224. IIIG1d 235. IIIG2c
203. IIIE3 214. IIIF2 225. IIIG1d

330 Chapter 5: Therapeutic Procedures

Therapeutic Procedures—Answers and Analyses
NOTE: The references listed after each analysis are numbered and keyed to the reference list located at the end of this sec-
tion. The first number indicates the text. The second number indicates the page where information about the ques-
tions can be found. For example, (1:114, 187) means that on pages 114 and 187 of reference 1, information about
the question will be found. Frequently, you will have to read beyond the page number indicated to obtain complete
information. Therefore, references to the question will be found either on the page indicated or on subsequent pages.

IIIA1 smoking cessation program, although they might

1. C. Patients who have severe pulmonary emphysema are smoke themselves. To begin, they should not smoke in
generally prone to airway collapse as a result of gener- the presence of the program participant. Family mem-
ating high intrapleural pressures during deep coughing. bers who smoke should encourage the participant as
The rapid ascent of the diaphragm resulting from the much as possible. They should avoid creating situa-
contraction of the abdominal muscles often compresses tions that could cause the participant to crave or to in-
the airways of emphysematous patients. This rapid in- crease the urge to have a cigarette.
crease in intrapleural pressure sometimes results in air If the participant receives nicotine-replacement ther-
trapping and ultimately in an ineffective cough. apy in the form of nicotine gum, the gum might help
These patients should be instructed to inhale a moder- the participant cope with an acute, high-stress situa-
ate volume of air (slightly more than a tidal breath, tion. The small dose of nicotine from the gum might
usually), then initiate a number of staccato-like expira- prevent the participant from relapsing.
tory efforts. The objective with this modified cough is (16:883–886, 1094–1095).
to minimize the occurrence of dynamic compression
of the airways to prevent air trapping and to improve IIIA1
the effectiveness of the cough.
5. C. Discharge planning of an asthma patient from the
(1:777–783, 805), (16:532). hospital should include the following components:
Components of Discharge Planning for Asthma
IIIA1 Patients
2. D. Documentation of a respiratory therapy procedure
should include the type of therapy, the date and time of • anti-inflammatory treatment
administration, the effects of therapy (including vital • bronchodilator therapy
signs before and after treatment), and any adverse reac- • knowledge of asthma triggers (recognition and
tions. These items constitute minimal documentation. avoidance techniques)
Additional information can be added where appropriate. • training to follow medical regimen
• information to manage acute exacerbation
(1:33–35), (15:445–446). • use of MDIs
• adverse effects of medications
IIIA1 • medications to avoid
3. D. Because of the lower density of a helium-oxygen • effects of bronchodilators
mixture, a patient’s cough would be compromised if • procedure to taper oral corticosteroids
the gas present in the lungs during the cough were pri- • encouragement to follow up
marily the helium-oxygen mixture. The patient should • measurement of peak expiratory flow rate
be instructed to take a few room-air breaths before at- An asthma patient generally does not perform spirom-
tempting to cough. The room-air breaths would elimi- etry at home. Therefore, knowing how to select the
nate the helium-oxygen gas mixture from the lungs best spirometric test is unnecessary. An asthma patient
and replace it with ambient air, thereby making the must know how to use a peak flow meter to monitor
cough more effective. lung function status.
(1:768), (15:888). (16:1011).

IIIA1 IIIA1
4. A. Family members of people who are trying to quit 6. C. Patient education is a critical component of a smoking-
smoking can be valuable assets to the participant of a cessation program. Aspects of smoking that must be

Chapter 5: Therapeutic Procedures 331

 taught include (1) the contents of cigarette smoke, (2) uation posed here, the patient’s heart rate increased
the physiologic effects of smoking, (3) withdrawal from a pre-treatment level of 75 beats/minute to 105
symptoms, (4) the effects of quitting smoking on me- beats/minute during the drug’s administration. The
tabolism, (5) behavior-modification techniques, (6) overall increase in the heart rate was 30 beats/minute.
avoiding urges and cravings to smoke, and (7) nutri- Therefore, the treatment must be halted immediately,
tion. Many more areas of concern need to be taught. and the physician must be notified. The patient must
also be closely monitored until the heart rate returns to
Teaching participants how to get others to quit smok-
the pre-treatment level. The CRT must also be on the
ing is not a component of a smoking-cessation pro-
alert for the development of any other adverse effects
gram. The purpose and goal is for the smoker to
(i.e., dizziness, lightheadedness, and nausea).
primarily focus on himself and to focus on what is nec-
essary for the participant to do. Including working (1:576–577), (15:181).
with other smokers would complicate the program and
would distract the participant from his own motives IIIA2a
and objectives. 10. D. Recordkeeping on the patient’s chart is an impor-
(16:883–886, 1094–1095). tant function of the CRT’s duties, because the medical
record is a legal document. All entries must be perti-
nent and accurate. If the CRT commits a charting error,
IIIA1
she must strike a line through the incorrect entry, print
7. B. The three levels of consciousness are (1) orientation the word “error” above the stricken entry, and com-
to time, (2) orientation to place, and (3) orientation to plete the charting from the point of the mistake.
person. A patient who is alert and oriented to time,
place, and person is said to be oriented  3. Such a pa- Erasing causes any rewritten information to be sus-
tient’s sensorium would be considered normal. pect, especially in court. The veracity of the rewritten
data or narrative often becomes questionable. The
A patient’s ability to perform a task requires varying CRT also must include her name and credentials at the
degrees of levels of consciousness, depending on the end of the charting.
nature and complexity of the task. Having a patient el-
evate an arm, for example, is much simpler than using (1:35).
an MDI properly.
IIIA2a
(1:301–302), (9:39).
11. B. Anytime a CRT is unable to interpret data, a re-
sponse to therapy, or a response to a change in therapy,
IIIA1 after documenting his inability to do so, he should im-
8. A. The CRT must remain calm and allow the patient to mediately seek a supervisor or other qualified person-
say what is on his mind. Once the patient has finished nel to interpret the data or the patient’s response.
talking, the CRT should calmly explain what therapy
needs to be done and attempt to elicit a response from The CRT should never speculate or render a judgment
the patient, indicating the patient understands the ra- about data or a situation if he is incapable of doing so.
tionale for the MDI. The CRT can request the patient Furthermore, blank spaces must never be left on the
to demonstrate the use of the MDI, because getting the patient’s chart.
patient actively involved might be less of a threat to the (1:35).
patient. Consequently, the patient might develop a
sense of independence. IIIA2a
(1:26). 12. C. Charting correctly and thoroughly is critical. Chart-
ing provides a mechanism for communication. Other
IIIA1b(4) therapists who treat the same patient can gain an un-
derstanding of the patient’s progress (or lack thereof).
9. C. Beta-two agonists potentially produce tachycardia
Any subjective complaints expressed by the patient
as an adverse or unwanted reaction. The CRT must
about the treatment must be recorded. At the same
monitor the patient’s pulse before, during, and imme-
time, objective findings related to the procedure must
diately after the administration of this type of bron-
be included. Subjective complaints include dizziness,
chodilator. The general guideline that is clinically
nausea, general discomfort, and shortness of breath.
adhered to is that if a patient’s heart rate increases by
Objective findings refer to auscultation data, pulse
more than 20 beats/minute during the course of the
rate, and respiratory rate.
treatment, the treatment must be immediately termi-
nated, and the physician must be informed. In the sit- (1:801).

332 Chapter 5: Therapeutic Procedures

IIIA2b(1) Idiosyncracy is a rare, paradoxical response to a med-
ication (e.g., onset or worsening of hypertension fol-
13. B. Assessment of this patient’s response to the chest lowing the administration of an antihypertensive
physiotherapy indicates that the patient’s lungs have drug). Toxicity is a dose-related side effect observed in
not yet cleared. Auscultation revealed that the lower most patients if enough of the drug is administered.
lobes were not well aerated and that rhonchi could be
heard in that lung region. The presence of rhonchi in- (8:32, 119), (15:177).
dicate the likelihood of secretions in the larger air-
ways. IIIA2b(1)
Because this patient has not been receiving chest phys- 16. A. The patient was hyperventilating and developing
iotherapy for too long (only two days), it might be acute respiratory alkalosis. Respiratory alkalosis is
somewhat premature to abandon it at this point. identified by a PaCO2 below the lower limit of normal.
Including a bronchodilator (beta-2 agonist) in the ther- This acid-base disturbance indicates that ventilation
apeutic regimen would be a reasonable approach, be- is exceeding the normal level. In other words, the
cause this patient is an asthmatic. The beta-2 agonist patient’s minute ventilation is exceeding his CO2 pro-
should be given before the chest physiotherapy, to take duction (V̇CO2 ). Clinical signs and symptoms associ-
advantage of the bronchodilatation effect of the med- ated with an acute respiratory alkalosis include
ication. Increasing the frequency of the chest physio- tachypnea, dizziness, sweating, tingling in the fingers
therapy from TID to QID might also be beneficial. and toes (paresthesia), and muscle weakness and
spasm (tetany). An acute respiratory alkalosis can be
(1:574–577), (9:45).
induced accidently in patients who are receiving IPPB
treatments when the treatments are administered im-
IIIA2b(1) properly. The effectiveness of any IPPB treatment is
14. B. Beta-adrenergic (sympathomimetics) bronchodila- greatly dependent on the CRT who is administering
tors often elicit beta-one and beta-two responses. Beta- the treatment.
one reactions cause the heart rate to increase (positive
chronotropism and positive inotropism), whereas the (1:884), (2:449), (9:83–84).
beta-two response (the pharmacologically favorable
one here) is bronchodilatation. Additionally, some beta IIIA2b(2)
agonists also cause the blood pressure to rise. Associ-
17. B. Whenever lung volumes or capacities are measured
ated with these cardiovascular side effects are dizziness
under ambient temperature pressure and saturated
or lightheadedness. Tremors, caused by stimulation of
(ATPS) conditions, they must be converted to body
beta-two receptors located on skeletal muscles, can also
temperature, pressure and saturated (BTPS) condi-
occur.
tions. Otherwise, if the values measured under ATPS
Based on these findings, sound clinical judgment dic- conditions are reported as such, the reported values
tates that the aerosol treatment of the beta-two agonist can be inaccurate by as much as 5% to 10%. Lung vol-
should be terminated immediately. The patient should umes or capacities measured under ATPS conditions
be encouraged to relax while breathing slowly and are lower than the corresponding values under BTPS
deeply. In the meantime, the physician needs to be no- conditions.
tified. Perhaps if the episode did not appear to be re-
Consider the values given in this question:
solving within five to 10 minutes, or if the situation
worsened, then an arterial puncture might be consid- ambient temperature: 24ºC
ered. If there were signs of significant respiratory dis-
tress, this situation could mandate an arterial blood-gas
ATPS
{ ambient pressure: 760 mm Hg
saturated with PH2O at 24ºC: 22.4 mm Hg
analysis, as well. These findings could all be related to
body temperature: 37ºC
the aerosol treatment, however, and might resolve
spontaneously in a short time.
BTPS
{ pressure: 760 mm Hg
saturated with PH2O at 37ºC: 47 mm Hg
(1:574–575), (8:103, 105, 111), (15:181).
FORMULA: P1V1 = P2V2
IIIA2b(1) T1 T2
15. B. Anaphylaxis refers to an extreme reaction charac- STEP 1: Correct P1 (barometric pressure) for water
terized by cardiovascular collapse (decreased blood vapor pressure (PH2O).
pressure and decreased cardiac output) and respiratory
distress. Tachyphylaxis describes the diminution of P1  PH2O = PB1corrected
pharmacologic effectiveness following repeated use. 760 mm Hg  22.4 mm Hg = 737.6 mm Hg

Chapter 5: Therapeutic Procedures 333

STEP 2: Correct P2 (barometric pressure) for water vapor What the CRT should recommend is that PEEP be in-
pressure (PH2O). stituted. To proceed as empirically as possible, how-
ever, another PEEP trial at the present FIO2 (0.70)
P2  PH2O = PB2corrected
should be conducted. In the situation presented here,
760 mm Hg  47 mm Hg = 713 mm Hg the data from the PEEP trial were presumably not er-
roneous. Either the data were misinterpreted or they
STEP 3: Convert T1, or 24ºC, to Kelvin (K).
were not understood by the person who was responsi-
K = ºC + 273 ble for the clinical decision. Inverse ratio ventilation
might ultimately be needed; however, at this time,
= 24ºC + 273
there is no data to support its application.
= 297 K
(1:901–902), (10:272–274), (15:899, 911).
STEP 4: Convert T2, or 37ºC, to Kelvin (K).
K = ºC + 273 IIIA2b(3)

= 37ºC + 273 19. A. The description of the expectorated material indi-

cates that the specimen is essentially saliva. Saliva is
= 310 K the substance that resides in the mouth. Saliva is of no
STEP 5: Insert the known values into the formula. diagnostic value and should be discarded. Not all pa-
tients can produce a sputum sample on command.
P1V1 P2V2
= Aerosol therapy should be employed to help obtain a
T1 T2 sputum sample. Another attempt at obtaining a spu-
tum sample should be made later. In fact, leaving a
(737.6 mm Hg) V1 (713 mm Hg) V2
= specimen cup with the patient and instructing him
297 K 310 K to use it if a productive cough occurs later would be
useful.
(737.6 mm Hg)(310 K) V1
V2 = (1:299), (9:26, 94–95).
(297 K)(713 mm Hg)
(228,656) V1 IIIA2b(3)
V2 =
211,761 20. C. The clinical signs displayed by this patient before
the administration of hyperinflation therapy are con-
V2 = (1.080)V1 sistent with lobar atelectasis. This patient’s clinical
Step 5 shows that the new volume (BTPS volume) will signs pointed to right lower-lobe atelectasis.
be 1.080 times the original volume (ATPS volume). Following the one-and-a-half days of hyperinflation
Therefore, because the volume (V1) at ATPS is 5.00 therapy, the patient demonstrated the clinical signs of
liters, the BTPS volume (V2) will be as follows: reversal of the atelectasis. Feelings of vibrations on the
V2 = (1.080)V1 affected area as the patient spoke indicated tactile
fremitus. During evaluation of the expansion of the
V2 = (1.080)(5.00 liters) thorax, the clinician’s thumbs moved 3 to 5 cm from
V2 = 5.40 liters the patient’s midline, indicating normal chest-wall
movement. Normal percussion notes are described as
(1:375), (17:256–258, 261). moderately low in pitch. The lack of adventitious
breath sounds reveals normal breath sounds. Radiolu-
IIIA2b(2) cency represents the presence of air in the alveoli of
18. B. The appropriate decision was not made following the the affected lobe.
PEEP study. The PEEP study indicated that the patient These changes in the patient’s clinical signs support
had a favorable response to PEEP levels up to 8 cm H2O, the resolution of atelectasis.
and at a PEEP level of 10 cm H2O, all the physiologic
markers used to evaluate the effectiveness of PEEP dete- (1:37, 410–412), (9:58–61, 65–66, 161–162) (See the
riorated. Apparently, as though the potential benefits of appendix in this text.)
PEEP were ignored, and the FIO2 was increased to 0.70.
IIIA2b(4)
The patient still appears to be unresponsive to the in-
21. B. Weaning a patient from mechanical ventilatory sup-
creased FIO2, indicating refractory hypoxemia. Re-
port via a Briggs adaptor (T-piece) is the time-tested
fractory hypoxemia was likely recognized when the
approach. This weaning method demands constant pa-
FIO2 was 0.60 and resulted in the PEEP trial.

334 Chapter 5: Therapeutic Procedures

 tient monitoring to ensure that the patient does not de- not sufficiently enough to warrant termination of the
teriorate during the process. Despite the great time de- treatment. The treatment should be continued. The pa-
mands that this weaning method places on the CRT, tient must be closely monitored for further increases in
this method is quite often effective. the heart rate and for other adverse reactions, however.
The CRT, aside from determining the patient’s suit- (1:576–577), (8:111), (15:181, 1032).
ability for weaning, must monitor the patient periodi-
cally during spontaneous breathing trials. The patient IIIA2b(5)
must not be allowed to fatigue too much, because the 23. A. Oxygen-induced hypoventilation sometimes occurs
patient might be placed at a psychological disadvan- with patients who are chronic CO2 retainers—a fre-
tage when ensuing weaning attempts are made. quent problem with COPD patients. Some COPD pa-
The patient in this problem certainly qualified as a tients experience hypoventilation when breathing
weaning candidate, based on the initial data. Within 10 moderate to high FIO2s. What happens with these pa-
minutes of the spontaneous breathing trial, however, tients is the peripheral chemoreceptors, which operate
the patient began to deteriorate. The data obtained dur- the hypoxic drive, receive too much oxygen and send
ing the weaning process indicated that the patient was fewer hyperventilatory signals to the medulla. These
rapidly fatiguing. patients then breathe less, experience a higher PaCO2
and a higher PaO2, and ultimately cease breathing.
Table 5-10 outlines the physiologic measurements that
support spontaneous breathing. The reader should Ordinarily, 2 liters/min. of oxygen from a nasal cannula
keep in mind that not one of these measurements alone (low-flow O2 delivery device) delivers a relatively low
represents the most important criterion during this level of oxygen (i.e., about 28%). When a patient’s tidal
process. Instead, multiple measurements increase the volume, respiratory rate, and pattern deviate from nor-
degree of predictability for successful weaning. mal, 2 liters/min. from a nasal cannula delivers more
oxygen than 28%. Therefore, regarding CO2 retainers,
Table 5-10: Physiologic criteria for weaning from me- using a nasal cannula must only occur when the patient
chanical ventilation is breathing relatively normally. Otherwise, because a
nasal cannula cannot furnish the patient with the inspi-
Acceptable ratory flow rate the patient demands when in respiratory
Measurment Values distress, a higher oxygen concentration will be given.
V̇E less than 10 liters/minute An air-entrainment mask (high-flow O2 delivery de-
f less than 25 breaths/minute vice) provides the patient with high enough inspiratory
MIP –20 cm H2O to –25 cm H2O flow rates to meet the patient’s demands. Conse-
FVC greater than 10 ml/kg
quently, the FIO2 from an air-entrainment device will
O2% less than or equal to 50%
remain essentially fixed, despite large variations in the
VT 3  IBW (kg)
VD/VT less than 0.6 patient’s inspiratory demands.
Q̇ S /Q̇ T less than 15% The SpO2 monitor showed the drop in arterial satura-
tion caused by the hypoventilation while the patient
used the nasal cannula. By the same token, the SpO2
This patient experienced a pulse increase of 20
rose when the patient’s oxygenation status improved
beats/minute. The ventilatory rate increased by 10
with the air-entrainment mask.
breaths/minute, while the MIP decreased by 12 cm
H2O. The vital capacity decreased to a level of 7 ml/kg, (1:742, 745, 746).
or a drop of 3 ml/kg.
(1:576–577), (15:181, 1032). IIIA2b(5)
24. B. The duration of a liquid-oxygen system can be ex-
IIIA2b(4) tended by having the patient use an oxygen-conserving
device such as a pendant nasal cannula or a reservoir nasal
22. B. Beta-2 agonists often cause tachycardia as an ad-
cannula. Oxygen-conserving devices require a lower flow
verse reaction. The CRT must monitor the patient’s
rate of oxygen than do standard nasal cannulas.
heart rate before, during, and immediately after the ad-
ministration of a beta-adrenergic bronchodilator. The For example, if a patient is receiving 2 liters/minute of
general guideline followed is that if a patient’s pulse oxygen via a conventional nasal cannula, a pendant
increases by more than 20 beats/minute in the course nasal cannula can deliver the same amount of oxygen at
of a treatment, the procedure should be terminated, 1 liter/minute. Oxygen-conserving devices are used to
and the physician should be notified. In the situation economize the use of oxygen, because liquid oxygen
presented here, the patient’s pulse has increased—but systems are more expensive than oxygen concentrators.

Chapter 5: Therapeutic Procedures 335

 In the situation presented in this question, the COPD IIIA2d
patient was receiving more oxygen than necessary. 27. A. Important aspects of therapeutic effectiveness are
The degree of hyperoxia cannot be assessed by a pulse the consistency and frequency of the intervention. If a
oximeter. An arterial blood-gas sample would be nec- therapeutic intervention (e.g., bronchodilator adminis-
essary to determine the patient’s PaO2. tration and chest physiotherapy) cannot be performed
(1:748–749, 1114–1115), (16:896–899). in a timely and consistent manner, the accomplishment
of the therapeutic goals might be compromised or
IIIA2c jeopardized.
25. C. The description of this patient should lead one to Among the considerations that should be contem-
suspect that the patient has pulmonary emphysema. plated are patient meal times and the scheduling of
Patients who have pulmonary emphysema characteris- other therapeutic-procedure interventions.
tically exhibit a barrel chest, i.e., the thorax appears to
For example, scheduling chest physiotherapy to coin-
be in a fixed, hyperinflated state. This chest-wall con-
cide with meal times is inappropriate. Similarly, aerosol
figuration results when the patient’s anteroposterior
therapy or bronchodilator administration should not be
(AP) chest-wall diameter equals or exceeds that of the
scheduled at the time when the patient is already sched-
transverse thorax. The enlarged AP diameter is caused
uled to be with the physical or occupational therapist.
by air trapping in the lungs, as well as by the patient’s
postural attempt to gain a mechanical advantage to ob- The need to maintain communication among the vari-
tain a sufficient volume of air to breathe. The hyperaer- ous health-care providers is essential for the accom-
ation (air trapping) also flattens the hemidiaphragms, plishment of the desired therapeutic outcome.
which can be confirmed by chest radiography—
(1:26–29).
placing these muscles at a mechanical disadvantage.
The hemidiaphragm is prone to fatigue. Fatigue of the
diaphragmatic muscles often results in the paradoxical IIIA2e
movement of the diaphragm, intercostal retractions, and 28. D. Each breath delivered by a mechanical ventilator
accessory ventilator-muscle usage. has four phases:
Emphysematous patients are often thin (emaciated) • the transition from inspiration to exhalation
because of their high-energy expenditure and caloric • exhalation
consumption associated with their increased WOB. • the transition from exhalation to inspiration
• inspiration
Auscultation of the chest usually reveals bilaterally di-
minished or absent breath sounds, because the air trap- Mechanical ventilators can also control four variables
ping and hyperinflated state reduces the transmission during inspiration:
of sound waves to the chest wall.
• flow
Therefore, from these observations, it appears as • volume
though this patient might benefit from a pulmonary re- • pressure
habilitation program where, among other considera- • time
tions, diaphragmatic and pursed-lip breathing can be
Consequently, these variables are both phase variables
taught to the patient.
and control variables. Both types of variables can be
(9:47, 52–53, 176), (15:780, 947). graphically represented as output waveforms by certain
mechanical ventilators. The output waveforms of the
IIIA2c control and phase variables are generated in relation to
26. A. The CRT must communicate effectively with other time. Three types of output waveforms are possible:
members of the healthcare team. The CRT must also • pressure waveforms
understand the roles of the various disciplines to de- • volume waveforms
termine who on the team has a need to know specific • flow waveforms
information regarding the patient. In this case, the pa-
tient’s nurse is the individual who oversees the details Each mechanical ventilator determines the shape of
of the patient’s bedside care. Because the nurse is re- the waveform representing the control variable. The
sponsible for documenting the patient’s nutritional and shape of the other two waveforms depends on the pa-
fluid intake and output, an episode of vomiting should tient’s compliance and airway resistance.
be reported to her. The exchange of information is a The horizontal axis of an output waveform is the time
matter of courtesy and good patient care. axis. For all of the three types of output waveforms
(1:779), (15:847). (pressure, volume, and flow), tracings above the hori-

336 Chapter 5: Therapeutic Procedures

 zontal axis indicate changes occurring during inspira- IIIA2f
tion. Conversely, tracings below the horizontal axis 30. B. Because this patient does not meet one of the es-
signify alterations taking place during exhalation. sential criteria for effectively using an MDI, a small-
Evaluation of output waveforms during mechanical volume nebulizer should be used. This patient cannot
ventilation offers important clinical information. The hold her breath long enough while using an MDI to al-
CRT can obtain the following clinical information low sufficient deposition and penetration of the bron-
from studying output waveforms: chodilator aerosol particles. A spacer is generally used
for patients who cannot coordinate the activation, in-
• the presence of auto-PEEP halation, and breath-hold.
• the patient’s WOB
• airway-resistance changes A small-volume nebulizer would be suitable here,
• lung compliance because it is assumed the patient can take a deep
enough breath. The problem is holding that breath.
(1:851–853, 955–959), (5:346–354), (16:650, Furthermore, the patient has not been described as a
683–686). shallow breather. In such cases, IPPB with a mask
29. B. The flow, volume, and pressure waveforms from a can be used.
mechanical ventilator delivering pressure-limited IMV (1:7), (8:41).
at 10 breaths/min. are shown in Figure 5-6.
Two pressure waveforms are shown. The one desig- IIIA2f
nated as Paw indicates airway pressure, and the one rep- 31. A. Despite the patient’s clinical signs, the patient’s
resented by Pes refers to the esophageal pressure. The SpO2 of 97% indicates that oxygenation is not a prob-
esophageal pressure estimates the intrapleural pressure. lem at this time. Therefore, continued monitoring is
Notice how the patient’s inspired and exhaled volumes warranted. If the patient’s SpO2 reaches 92% or less,
differ on the volume (VT) curve. The exhaled volumes oxygen therapy would be indicated.
tracing fails to return to the baseline. This disparity be- (1:7–8), (16:380).
tween the inhaled and exhaled tidal volume indicates
there is a loss of volume during inspiration. The vol- IIIA2f
ume loss can be substantiated by evaluating the flow
32. D. This patient did not respond favorably to postural
(V̇) waveform. During pressure-limited ventilation, a
drainage and directed cough for the removal of
decelerating flow waveform is expected. In this in-
tracheobronchial secretions and the reversal of right
stance, the inspiratory flow stays elevated throughout
middle-lobe atelectasis. Having the patient cough
inhalation as the ventilator works to maintain the tar-
more vigorously would not be appropriate, because
geted pressure despite the system leak.
the directed cough technique employs a rather forceful
(1:959). cough. Perhaps the forced expiratory technique (FET)

L/s U
2
2.0

L UT

–0.5
60
PAW
cm
H2O
–20
40
PES
cm
H 2O
–40

Figure 5-6: Flow, volume, and pressure waveforms reflecting pressure-limited IMV
at a mechanical rate of 10 breaths/min. Bear Medical Systems, Thermo Respiratory
Group.

Chapter 5: Therapeutic Procedures 337

 or huffing would be useful. They are also called active have helped lower the risk of nosocomial infections.
cycle of breathing and autogenic drainage.
(1:426–430), (16:437–438).
Incentive spirometry is not intended to remove tra-
cheobronchial secretions; rather, it is useful for revers- IIIA3
ing or preventing atelectasis. In this case, using
35. A. The Centers for Disease Control and Prevention
aerosol or high-humidity therapy with positive expira-
(CDC) and the Hospital Infection Control Advisory
tory pressure (PEP) might be more effective.
Committee (HICAC) have published guidelines for
(16:510–511, 518–519, 529–530). isolation practices in hospitals.
The new guidelines contain two levels of precautions:
IIIA3
33. C. The Human Immunodeficiency Virus (HIV) appears • standard precautions
to be transmitted via certain forms of contact with the • transmission-based precautions
blood (blood products), vaginal secretions, or semen The standard precautions replace universal precau-
from people who are HIV positive. The forms of trans- tions. Standard precautions include the following con-
mission generally involve certain forms of behavior, siderations:
i.e., homosexuality, I.V. drug abuse, and heterosexual
contact with people who are infected with HIV. A • handwashing
small percentage of patients have become infected • gloves
through the transfusion of blood or blood products. • masks, eye wear, or a face shield
• gowns or aprons
Because contact with body fluid from an HIV-infected • patient transport
person potentially places a non-HIV infected person at • patient-care equipment/occupational health and
risk, health-care personnel need to adhere to certain pre- blood-borne pathogens
cautions. For example, when a CRT is about to perform • linen and laundry
an arterial puncture procedure on a known HIV-infected • eating utensils, dishes
patient, the CRT should perform the following actions: • routine and terminal cleaning/environmental con-
• wear gloves on both hands trol
• wear protective eye shields or glasses Transmissions-based precautions encompass three cat-
• wear a surgical mask egories: (1) airborne, (2) droplet, and (3) contact. Stan-
• wear a gown dard precautions apply to all patients, regardless of
The patient does not need to wear a surgical mask. diagnosis. Again, this category replaces universal pre-
cautions. Standard precautions are designed to reduce
(4:323). the risk of transmission of microorganisms from both
recognized and unrecognized sources of infection in
IIIA3 the hospital. Standard precautions apply to blood, all
34. D. The promulgated guidelines for practice to reduce body fluids, secretions, and excretions (except sweat),
the incidence of nosocomial infections of ventilator regardless of whether they contain visible blood, non-
patients are as follows: (1) the patient’s breathing cir- intact skin, and mucous membranes.
cuit should be changed every 24 hours (according to (Centers for Disease Control and Prevention; Hospital
the Centers for Disease Control and Prevention); (2)
Infection Control Advisory Committee).
the humidifier reservoir should be completely emptied
before refilling it with sterile water; (3) the patient
breathing circuit should be evacuated frequently, and IIIA3
the condensate should not be allowed to drain back 36. C. In additional to standard precautions, droplet pre-
into the humidifier reservoir; and (4) the personnel cautions are used for a patient who is known or sus-
who are in contact with the patient and/or equipment pected to be infected with microorganisms transmitted
should wash their hands frequently. by large-particle droplets (over a distance of 2 to 3
feet) that might be generated during coughing, sneez-
Regarding the practice of changing ventilator circuits,
ing, talking, or procedure performance (such as bron-
some institutions have discovered that replacing venti-
choscopy or suctioning).
lator tubing every 10 to 12 days results in no difference
in nosocomial infection, compared to changing cir- Conditions or illnesses that require droplet precautions
cuits every 24 hours. Closed-system suction catheters are listed in Table 5-11.

338 Chapter 5: Therapeutic Procedures

Table 5-11: Conditions/illnesses requiring droplet precau- IIIA3
tions
38. A. According to the Centers for Disease Control and
• invasive Hemophilus influenzae, type B Prevention, four types of infection control precautions
• invasive Neisseria meningitidis exist: (1) standard precautions, (2) airborne precau-
• diphtheria tions, (3) droplet precautions, and (4) contact precau-
• mycoplasma pneumonia tions.
• pertussis
• pneumonic plague In addition to standard precautions, droplet precautions
• streptococcal infections are used for a patient who is known or suspected to be
• scarlet fever infected with microorganisms transmitted by large-
• adenovirus particle droplets (a distance of more than two to three
• influenza feet) that might be generated by coughing, sneezing,
• parvo virus B19
talking, or procedure performance (i.e., bronchoscopy).
• rubella
Conditions and illnesses requiring droplet precaution
include: Hemophilus influenzae, type B invasive Neis-
(Centers for Disease Control and Prevention; Hospital Infec-
seria meningitidis, diphtheria, mycoplasma pneumo-
tion Control Advisory Committee).
nia, pertussis, Streptococcus pneumoniae, adenovirus,
parvo virus, and German measles (rubella).
IIIA3
37. D. Herpesvirus varicellae, or varicella-zoster virus (Centers for Disease Control and Prevention).
(VZV), is a DNA virus surrounded by a lipid envelope.
This virus causes chicken pox (varicella) as a primary IIIA3
infection and shingles (zoster) when reactivated. 39. B. Two percent glutaraldehyde, at a pH ranging from
7.5 to 8.5, kills Mycoplasma tuberculosis. Glutaralde-
Chicken pox is usually a mild, generalized, vesicular hyde is classified as a high-level disinfectant that does
eruption occurring primarily in children who are not damage metals, plastic, rubber, or lenses, making it
younger than 10 years of age. Lesions appear first on suitable for sterilizing bronchoscopes.
the scalp or trunk and spread toward the extremities.
Lesions appear for several days, so different stages The procedure for cleaning/disinfecting a broncho-
(papules, vesicles, and crusts) are present simultane- scope is as follows:
ously. 1. Use a detergent in water to clean external surfaces,
Although normally a mild disease, chicken pox can be channels, and ports.
severe and even fatal—particularly in immunosu- 2. Detach and sterilize biopsy forceps and specimen
pressed children. Primary infection is more severe in brushes.
adults. Complications such as encephalitis and dis- 3. Completely submerge the bronchoscope in the glu-
seminated fatal disease can occur but are rare. taraldehyde solution.
4. Allow the instrument and all its ports and channels
Infection-control measures include standard and con- to remain in the glutaraldehyde for 20 minutes.
tact precautions. Patients are generally placed in a pri- 5. After removing the instrument from the glutaralde-
vate room. They can cohort with approval from the hyde, rinse the bronchoscope and all its ports and
appropriate hospital authority, however. Clean, non- channels with sterile water. Rinsing with tap water
sterile gloves must be worn when entering the room. followed by an alcohol rinse is also acceptable.
Gloves must be changed after contact with infective or 6. Forced air is used to completely dry the instrument
potentially infective material. Gloves must be removed and all its ports and channels.
and hands must be washed before leaving the room.
(1:45, 50), (16:292–293).
A clean, non-sterile gown must be worn into the room
if: IIIA3
— clothing might contact the patient or infective or 40. A. Reusable articles that have been contaminated, or
potentially infective surfaces suspected of having been contaminated, with M. tu-
— the patient has diarrhea, an ileostomy, or a berculosis must be wrapped in a plastic bag and la-
colostomy, or wound drainage not contained by a beled before being sent to the decontamination and
dressing reprocessing area. Respiratory care equipment that is
disposable should be bagged and then discarded in the
The gown must be removed before leaving the room.
patient’s room after having been used on a patient who
(Centers for Disease Control and Prevention; Hospital is known or suspected of having had pulmonary tuber-
Infection Control Advisory Committee). culosis.

Chapter 5: Therapeutic Procedures 339

 The type of bag used for either reusable or disposable capillaries is about 30 mm Hg, whereas the pressure in
articles must be an impervious one to prevent inadver- the venous tracheal vessels is less than 20 mm Hg.
tent contamination to personnel or to the environment
(1:610), (2:429), (16:577).
from the article(s) in the bag. If the bag is not imper-
vious, double-bagging should be employed.
IIIB1a
(1:54).
44. C. With the patient supine, the pharyngeal end of the
oropharyngeal airway is inserted and positioned be-
IIIB1a tween the base of the tongue and the posterior pharyn-
41. C. The trachea should be suctioned before cuff defla- geal wall. The buccal end insertion is limited by the
tion to make the airway as clear as possible. Also, the gingiva or teeth. At times, the patient’s mouth needs to
oropharynx should be thoroughly suctioned before be forced open.
cuff deflation to prevent the aspiration of secretions
pooled above the cuff when the cuff is evacuated. Once (1:590), (16:565–567).
the minimal-leak technique has been employed, con-
tinuous monitoring is required to maintain cuff infla- IIIB1a
tion at a particular level. Regarding ventilator patients, 45. A. According to the AARC Clinical Practice Guide-
as peak inspiratory pressure changes, adjustments of lines for Humidification During Mechanical Ventila-
cuff volume are needed. If the minimal leak technique tion, a heated humidifier should be set to deliver an
was instituted when the peak inspiratory pressure was inspired gas temperature within the range of 33  2ºC
high, the volume in the cuff would be too large in the (i.e., 31ºC to 35ºC) to an intubated patient. The patient
event of a decrease in delivery pressure. The opposite in this question is inspiring gas at 35ºC. Consequently,
situation is likewise true. nothing needs to be done to the humidifier temperature
(1:610, 616–619), (2:429), (16:576, 606). setting. Raising the temperature setting at the humidi-
fier to 55ºC or 60ºC would likely cause the inspired
gas to be heated too much and possibly cause thermal
IIIB1a
injury to the lungs. Lowering the humidifier tempera-
42. D. Endotracheal and tracheostomy tubes generally re- ture setting would compromise the humidity delivered
quire an intracuff pressure between 27 to 33 cm H2O to the patient’s airway and increase the humidity
or 20 to 25 mm Hg. deficit (i.e., contentcapacity at 37ºC).
In the example presented here, a larger-than-normal The tubing in this situation will need to be drained pe-
pressure exists inside the endotracheal tube cuff; i.e., riodically, because water will condense in the tubing as
40 cm H2O. Despite this excess pressure, however, the gas cools in transit from the heated humidifier to
volume is nonetheless leaking around the cuff. The the patient.
leak is substantial; i.e., only 500 ml of the preset 900
ml are being measured. (1:90–91, 667–671).

The endotracheal tube is likely too small, which there-

fore requires larger intracuff volumes to seal the air- IIIB1a
way. An endotracheal tube with a larger I.D. diameter 46. B. Both lungs should be auscultated after endotracheal
would be more suitable. intubation to determine whether ventilation is going to
both lungs, and auscultation of the abdomen is useful
(1:609–610), (2:428–429), (16:576). to help rule out inadvertent intubation of the esopha-
gus. Visual inspection of the chest wall helps deter-
IIIB1a mine air movement within the lungs. A portable chest
43. C. After the tube (nasal, oral, or tracheostomy) is in X-ray indicates the position of the tube in relationship
position, the cuff is inflated. The volume placed into to the carina. The radiopaque line that extends down to
the cuff should be just enough to create a complete seal the distal tip of the endotracheal tube assists in locat-
during mechanical ventilation. A slight amount of air ing the tube’s position.
should then be aspirated out of the cuff to establish a
Performing end-tidal CO2 (PETCO2) is another method
slight leak around the cuff during the inspiratory
of assessing proper endotracheal tube placement. If the
phase. This technique serves to reduce the hazard of
PETCO2 level is around 5.6%, the CRT can be confi-
pressure damage to the tracheal mucosa.
dent that the endotracheal tube has been placed in the
The intracuff pressure that should be achieved is less trachea and not in the esophagus. Proper tube position
than 20 mm Hg. The mean pressure in the tracheal in the trachea in relation to the carina, however, can be

340 Chapter 5: Therapeutic Procedures

 confirmed radiographically or via fiberoptic bron- the thorax to generate a cough. While lying in the supine
choscopy. position, tension on the abdominal muscles makes it dif-
ficult for a patient to cough effectively. Ideally, the pa-
(1:599, 606–607).
tient should be relaxed and sitting up, with the shoulders
rotated forward and the spine slightly flexed.
IIIB1b
47. C. Chronic bronchitics are generally of stocky body (1:298–299, 794), (16:513–515).
build. They are often referred to as “blue bloaters,” a
term that describes the ashen, dusky skin color IIIB1e
(cyanosis) produced by their chronic hypoxemia. Dur- 50. D. Cuff pressures higher than 42 cm H2O or 30 mm Hg
ing exacerbations of their chronic bronchitis, the fol- will impair arterial capillary blood flow to the tracheal
lowing signs are often present: tissue. Increased tracheal cuff pressures will cause mu-
cosal damage. One should always attempt to establish
(1) the accessory ventilatory muscles are used, pro-
intracuff pressures less than 24 cm H2O or 18 mm Hg
ducing:
when possible. The CRT should verify endotracheal
• increased WOB tube placement by auscultation before securing the
• increased oxygen consumption (V̇O2) tube. Capnography (end-tidal PCO2) can be useful to
• hypoxemia resulting from insufficent ventilation determine tube placement, but auscultation and chest
• intercostal retractions (depending on the de- X-ray are superior methods. Fiberoptic bronchoscopy
gree of respiratory distress) can also be used to determine proper tube position. A
normal-sized adult male (5-feet 10-inches, 150 lbs)
(2) wheezing revealed upon auscultation
will have an insertion depth of approximately 23 cm
(3) peripheral edema, particularly associated with from the teeth when the tube is properly placed.
right-ventricular failure, following or concurrent
(1:609–610), (16:576–577).
with cor pulmonale (later stages). The hypersecre-
tive condition normally present in chronic bronchi-
tis often advances to a greater amount of muco- IIIB2a
purulent sputum production during exacerbations 51. B. The patient is likely experiencing increased in-
associated with pulmonary infections. Patients at tracranial pressure; therefore, she should be removed
this point usually have a great deal of difficulty ex- from the Trendelenburg position and reassessed before
pectorating these secretions. continuing in other lung areas.
(1:442, 444–445), (9:294), (15:212–214), (AARC Clinical Practice Guidelines for Postural
(16:1025–1028). Drainage Therapy), (1:796).

IIIE3 IIIB2a
48. B. The therapeutic interventions most commonly used 52. B. Chest physiotherapy is often useful in mobilizing
during an acute exacerbation of chronic bronchitis tracheobronchial secretions. Tracheobronchial secre-
include oxygen administration and bronchodilator tions are frequently associated with coarse rhonchi. If
therapy. When specific pathogens are identified, the these secretions can be mobilized, the coarse rhonchi
appropriate antibiotic therapy should be implemented. can likely be eliminated.
Careful attention should be given to adequate humidi-
(AARC Clinical Practice Guidelines for Postural
fication of secretions and secretion removal; that is,
Drainage Therapy), (1:796), (15:788–790), (16:504).
chest physiotherapy. Although ultrasonic therapy is
one approach to providing adequate humidification,
ultrasonic aerosols are often aggravating and can in- IIIB2a
duce bronchospasm. The patient is usually instructed 53. C. Positioning a patient who requires chest physio-
to consume large amounts of water to thin out these se- therapy to the right middle lobe (lateral and medial
cretions and to facilitate expectoration. This latter rec- segments) encompasses placing the patient on her left
ommendation has no empirical basis, however. side, in a slight Trendelenburg position, with a three-
quarter turn toward the supine position.
(1:1:448), (2:286–287), (15:212–214),
(16:1028–1033). (1:800), (16:514).

IIIB1d IIIB2a
49. B. Positioning is an essential part of effective cough ma- 54. A. If the bronchial hygiene technique chosen for a pa-
neuvers. Sitting upright enables the patient to compress tient requires the patient to follow instructions and per-

Chapter 5: Therapeutic Procedures 341

 form certain maneuvers, the patient must be alert and return. Hypertension can also develop from hypoxemia
oriented. Because the patient in this question is alert and/or increased sympathetic tone to the myocardium.
and oriented, she can cooperate with the CRT during
If any of these adverse reactions develop during endo-
the application of bronchial-hygiene therapies.
tracheal suctioning, the procedure must be terminated
Postural drainage takes advantage of gravity to assist with immediately. Then, the patient must be ventilated and
the movement of retained secretions from peripheral air- oxygenated.
ways to the more central airways. This bronchial hygiene
(1:619–620), (16:606–607).
technique, accompanied by directed coughing, can effec-
tively remove secretions from the tracheobronchial tree.
The application of directed coughing when the patient’s IIIB2c
secretions are in the peripheral airways is ineffective. For 58. D. As long as the patient’s vital capacity is less than 15
directed coughing to be beneficial, the patient’s secretions ml/kg of ideal body weight, IPPB is indicated. Such a
must be in the central airways. vital capacity signifies that the patient cannot breathe
deeply. Therefore, IPPB would be beneficial. The
CPAP, EPAP, and PEP all require an alert and oriented bronchodilator should be nebulized in-line with the
patient and would be suitable bronchial hygiene tech- IPPB treatment. A small-volume nebulizer might not
niques for this patient. These techniques, however, be suitable for this patient because of the patient’s
must be used in conjunction with some form of expi- likely inability to breathe deeply.
ratory maneuver; i.e., directed cough, forced expira-
tory technique (huffing), active-cycle breathing, or (1:778–779), (15:846), (16:532–533).
autogenic drainage. Therefore, CPAP, EPAP, and PEP
therapy without coughing or some other form of expi- IIIB2c
ratory maneuver are ineffective in removing retained 59. D. The lungs possess extensive parasympathetic inner-
secretions by themselves. vation (afferent and efferent fibers)—especially the
(1:796, 803–810). bronchial smooth muscles. Sympathetic innervation is
entirely absent. Despite the lack of sympathetic neural
pathways, however, bronchial smooth muscle and pul-
IIIB2b
monary vascular smooth muscle have alpha and beta
55. D. To ensure adequate oxygenation and to prevent hy- receptors.
poxemia, the patient should be oxygenated before and
after each suction effort. To avoid possible trauma to Parasympathetic stimulation (i.e., stimulation of the
the airways, the suction time should be fewer than 15 cholinergic receptors on the surface of the bronchial
seconds. Suction pressure should not be applied when smooth muscle cells) activates guanylate cyclase, an
the catheter is being inserted. The heart rate and enzyme that catalyzes the conversion of guanosine
rhythm should always be monitored during suctioning. triphosphate (GTP) to the cyclic nucleotide 3’,
Suction pressure for adult patients is recommended to 5’-guanosine monophosphate (cyclic GMP). Increased
be –100 to –120 mm Hg. bronchial smooth muscle intracellular levels of cyclic
GMP presumably result in bronchoconstriction.
(1:616–620), (16:606–607). Therefore, the blockade of the cholinergic receptor
sites in the lungs will contribute to a decreased intra-
IIIB2b cellular level of cyclic GMP and produce bronchial
56. B. During nasotracheal suctioning, the catheter is smooth muscle relaxation—bronchodilatation.
blindly passed through the vocal cords into the trachea.
(1:577–579), (8:92), (15:178), (16:491–492).
When the catheter tip advances through the cords, the
patient’s voice will become hoarse and whispery. The
cough reflex is also strongly stimulated. IIIB2d
60. C. Many COPD patients, especially those who have
(1:620). severe obstruction, are prone to bronchiolar collapse
if they take a deep breath and exhale forcefully. The
IIIB2b destructive emphysematous process causes the lung
57. C. A number of conditions can occur prompting termi- tissue to lose its elastic recoil. When subjected to ele-
nation of the endotracheal suctioning procedure. For ex- vated intrapleural pressures, the airways experience
ample, the mechanical stimulation of the airway by the dynamic compression at an earlier point if the exhala-
suction catheter can cause a cardiac dysrhythmia (fre- tion is forceful, as opposed to a more moderate exha-
quently bradycardia). Similarly, stimulation of the ca- lation.
rina by the catheter can elicit the vagal-vagal response,
Therefore, severe COPD patients should generally be
which is reflex bradycardia and hypotension. Coughing
instructed to take a breath slightly larger than their
can induce hypotension as a result of decreased venous

342 Chapter 5: Therapeutic Procedures

 tidal volume and to exhale in short, staccato-like Therefore, if the patient maintained displacement in
bursts. This maneuver elevates intrapleural pressure, the first two chambers for two seconds, the calculated
but not to the extent experienced during a rapid, force- volume would be as follows:
ful exhalation.
900 cc/sec  2 sec
(1:772), (2:444), (15:166, 1034). V=
1,000 cc/liter
IIIB2d = 1.8 liters

61. B. The flutter device, used for secretion removal, has (1:776), (16:531).
the capability of generating a pressure ranging from 10
to 25 cm H2O. Pressure can vary within this range, IIIC1a
based on the patient’s expiratory flow rate. The slower 64. C. Whenever a patient is receiving aerosol therapy or
the expiratory flow rate, the lower the pressure. Con- a nebulized medication, he must be instructed to
versely, the greater the expiratory flow rate, the higher breathe slowly and deeply and to breath-hold at end-
the pressure. inspiration. This breathing pattern has been shown to
improve deposition and penetration of the aerosol par-
The angle at which the flutter device is held to the pa-
ticles and/or nebulized medication.
tient’s mouth alters the frequency of the vibrations gen-
erated in the lungs. The maximum frequency is 15 Hz. (2:434–435), (16:441).
(1:810–811), (13:355).
IIIC1b
IIIB2d 65. B. If a pressure-limited, volume-variable device cycles
off prematurely, adequate lung inflation is jeopardized.
62. C. The flutter valve is a secretion-clearance device.
To correct this problem, the CRT can either reduce the
Many patients find this device more useful than pos-
flow rate (reduces turbulence and lessens airway resis-
tural drainage, intrapulmonary percussion ventilation
tance) or increase the pressure limit (accommodates
(IPV), or PEP breathing.
higher pressures).
The flutter valve has proved to be as beneficial as other
Decreasing the flow rate will increase inspiratory time
forms of secretion removal in the treatment of cystic fi-
and decrease ventilatory frequency. Increasing the
brosis. The flutter has shown remarkable results in se-
pressure while maintaining a constant flow increases
cretion removal associated with allergic asthma,
inspiratory time and decreases frequency.
however. Allergic asthmatics have demonstrated im-
proved pulmonary function after only one month of (1:781–782).
flutter-valve therapy.
The flutter device can generate a range of pressure IIIC1b
from 10 to 25 cm H2O. Pressure can be altered within 66. D. The CRT should approach the patient from the back
this range by having the patient exhale at different flow side, place her fist on the patient’s epigastrium, place
rates. The lower the expiratory flow rate, the lower the her other hand on top of the hand held in a fist, and ap-
pressure, and vice-versa. ply successive compressions to the epigastrium until
the patient is relieved. Essentially, the Heimlich ma-
The flutter valve also produces a vibration frequency neuver is performed in this situation.
of 15 Hz, based on the angle of the device. Therefore,
as the angle at which the flutter valve is held changes, Alternatively, the CRT can place her hands on both lat-
the frequency also changes. eral aspects of the patient’s chest wall and apply a
number of squeezes to overcome the airway collapse,
(1:810–811), (13:355). thereby removing the air from the patient’s lungs.

IIIC1a Instructing emphysema patients not to generate a cough

from the maximum end-inspiratory (total lung capacity)
63. B. In the device shown, each tube is calibrated so that
position is important. Rather, coughing from the mid-
full displacement of the ball corresponds to a specific
inspiratory position might prevent the buildup of too
flow rate, i.e., 600 cc/sec, 900 cc/sec and 1200 cc/sec,
great an intrathoracic pressure, thus preventing airway
respectively. The relationship below demonstrates
collapse. Avoiding dynamic compression of the airways,
how the inspired volume is estimated.
which is caused by a positive transmural (across the air-
V̇ (cc/sec)  time (sec) way wall) pressure, would be to the patient’s advantage.
V (liters) =
1,000 cc/liter (15:847).

Chapter 5: Therapeutic Procedures 343

IIIC1b
67. C. Patients who receive IPPB treatments often hyper-
ventilate. If the patient is allowed to continue hyper- (
= 0.3 (760 torr – 47 torr) – 40 torr 0.3 +
1– 0.3
0.8
)
ventilating, he might experience dizziness, loss of
consciousness, tetany, and paresthesia. Tetany is the = 0.3(713 torr)  40 torr (1.175)
occurrence of muscle tremors or spasm, while pares- = 213.9 torr  47 torr
thesia is the sensation of peripheral numbness or tin-
gling. Both of these clinical manifestations develop = 167 torr
from acute alveolar hyperventilation. To help alleviate STEP 2: Apply the following formula to solve for the
these signs and symptoms, the CRT must encourage unknown alveolar PO2:
the patient to breathe more slowly.
desired PaO2 known PaO2
(1:779), (2:449), (15:847). =
unknown PAO2 calculated PAO2
IIIC1b 70 torr 50 torr
68. C. Gastric insufflation can be a problem during an =
unknown PAO2 167 torr
IPPB treatment, particularly when the treatment is ad-
ministered by mask. A concomitant risk of vomiting (70 torr)(167 torr)
and aspiration exists. A flanged mouthpiece can pre- unknown PAO2 = = 234 torr
50 torr
vent leakage at the mouth. If it is necessary to use a
mask for an obtunded patient, avoidance of high infla- STEP 3: Use the alveolar air equation, once again in-
tion pressures and use of a nasogastric tube can mini- serting the unknown alveolar PO2 and solving for the
mize the problem. desired FIO2.
(1:779), (2:449), (15:847). 234 torr = FIO2 (760 torr – 47 torr) – 40 torr/0.8
234 torr = FIO2 (713 torr) – 50 torr
IIIC1d
234 torr + 50 torr = FIO2 (713 torr)
69. C. When a patient’s cardiopulmonary status is con-
stant, the following formula can be applied. 284 torr
desired FIO2 = = 0.40
desired FIO2 actual FIO2 713 torr
=
desired PaO2 actual PaO2 (10:250–252), (17:47, 50, 131–132, 265).
Therefore, because the actual FIO2 is 0.30 and the ac-
tual arterial PO2 is 50 torr, the FIO2 needed to achieve IIIC1d
an arterial PO2 of 70 torr can be determined. 70. B. The tidal volumes for a volume-cycled ventilator
should be set between 10 to 15 milliliters per kilogram
desired FIO2 0.30
= of the patient’s ideal body weight. Therefore, her tidal
70 torr 50 torr volume can be determined from the following calcula-
tion:
(70 torr)(0.30)
desired FIO2 = STEP 1: Use the following formula to determine the
50 torr patient’s approximate ideal body weight expressed in
21 pounds (lbs). This patient is 5-feet 3-inches, or 63
= inches tall.
50
ideal body weight (lbs) female
= 0.42
= 105 + [5  (height in inches  60)]
Alternatively, the desired FIO2 can be calculated ac-
cording to the following steps: = 105 + [5  (63  60)]

STEP 1: Calculate the alveolar PO2 by using the alve- = 120 lbs
olar air equation and the known FIO2.* STEP 2: Convert 120 lbs of ideal body weight to kilo-
grams (kg).
PAO2 = FIO2 (PB – PH2O) – PaCO2 FIO2 + ( 1– FIO2
R
) ideal body weight (kg) =
120 lbs
= 55 kg
*The alveolar air equation can also be expressed as 2.2 lbs/kg
PAO2 = FIO2 (PB  PH2O)  PaCO2/R. STEP 3: Multiply 10 to 15 ml/kg by the ideal body
weight in kg.

344 Chapter 5: Therapeutic Procedures

 initial VT (ml) = 15 ml/kg  55 kg = 820 ml Once the IBW in pounds is known, it can then be con-
verted to kilograms in the following manner:
Therefore, an initial tidal volume of 800 ml would be
appropriate for this patient. IBW lbs
= IBW kg
The formula for calculating the approximate ideal 2.2 lbs/kg
body weight in pounds for a male is shown as follows: The aforementioned guidelines can now be used to es-
ideal body weight (lbs) male tablish an initial tidal volume for a ventilator patient.
= 106 + [6  (height in inches  60)] Although these different rules of thumb are convenient
(1:897–899), (10:207–208). to use, the CRT must remember that they are only
guidelines, and that the ultimate determinant for subse-
IIIC1d quent tidal volume and other ventilator settings is arte-
rial blood-gas analysis. The NBRC uses the guideline
71. A. The patient described here is already receiving an
of 10 to 15 cc/kg of ideal body weight.
FIO2 of 0.60 with a PEEP of 3 cm H2O but is only able
to attain an arterial PO2 of 44 torr. This oxygenation sta- (1:897–899), (2:514–515), (10:207–208),
tus fits the definition of refractory hypoxemia. Refrac- (15:717, 966–967).
tory hypoxemia is defined as a patient’s inability to
achieve an arterial PO2 of 60 torr while breathing an FIO2 IIIC1d
of at least 0.50. Refractory hypoxemia is not amenable to 73. B. Generally, a patient’s tidal volume can be estimated
oxygen therapy, because the physiologic basis for this by multiplying his ideal body weight in kilograms by
hypoxemia is capillary shunting (perfused but unventi- 10 to 15 ml/kg. The key word here is ideal. For exam-
lated alveoli). Therefore, when a patient experiences re- ple, a Pickwickian syndrome (alveolar hypoventilation
fractory hypoxemia, PEEP is generally indicated. syndrome) patient would not be correctly ventilated if
Although the patient discussed here already has PEEP, his actual body weight in kilograms was multiplied by
the amount (3 cm H2O) is so slight that increasing it to 8 10 to 15 ml/kg when establishing an initial ventilator
cm H2O is reasonable in light of an FIO2 of 0.60. The pa- tidal volume setting. Rather, the patient’s ideal body
tient’s cardiovascular status must be monitored, however, weight in kilograms—that is, what the patient’s weight
to evaluate the patient’s response to the increased PEEP. should be for his height and sex—is multiplied by 10
to 15 ml/kg.
(1:901–902), (2:407, 545), (10:264–268), (15:731).
In certain specific cases, such as in acute exacerbation
IIIC1d of COPD or ventilatory failure caused by status asth-
maticus, this general guideline is dispensed. In these
72. A. The guidelines that are frequently used to establish situations, some clinicians advocate using lower tidal
an initial tidal volume for a mechanically ventilated pa- volumes, e.g., 7 to 10 ml/kg of ideal body weight, to
tient is 10 to 15 cc/kg of ideal body weight. Although avoid the development of auto-PEEP and to reduce the
this guideline refers to the ideal body weight, patients risk of barotrauma.
who are obese generally require tidal volumes near the
upper end of the prescribed range. Cachectic patients, (1:897–899), (2:514–515), (10:207–208), (15:709, 717).
on the other hand, are frequently ventilated near the
lower end of the range. Patients who have specific IIIC1d
types of pathophysiologies (for example, status asth- 74. A. Increasing the preset pressure on a pressure-cycled
maticus and COPD with acute ventilatory failure) are ventilator will increase the inspiratory time and de-
recommended to receive tidal volumes within the range crease the ventilatory rate, assuming that all the other
of 7 to 10 cc/kg of ideal body weight. The recommen- controls remain constant. More volume can be deliv-
dation for using lower tidal volumes in conjunction ered as a result of increasing the preset pressure, be-
with these types of patients is to reduce the likelihood cause inspiration continues until the preset pressure is
of developing auto-PEEP and barotrauma in general. achieved.
If the patient’s ideal body weight is unknown, the fol- (1:845), (10:82, 85), (16:655).
lowing formulas (male and female) can be used to cal-
culate this factor: IIIC1d
male: 106 + 6 (height in inches  60) 75. D. Hypoxemia that does not respond to increases in
= IBW in pounds FIO2 should be treated with increased levels of PEEP.
Lung injury, such as pulmonary contusions, can result
female: 105 + 5 (height in inches  60) in a restrictive process which can increase intrapul-
= IBW in pounds monary shunting (i.e., capillary shunting plus venous

Chapter 5: Therapeutic Procedures 345

 admixture, or shunt effect). Appropriate levels of PEEP 950 cc/breath12 breaths/min. = 11,400 cc/min.
will increase the functional residual capacity, decrease
STEP 2: Determine the spontaneous V̇E.
intrapulmonary shunting, and improve oxygenation.
V̇Espontaneous = V̇Eoverall – V̇Emechanical
(1:879–880), (10:264–268), (15:909), (16:620–621).
= 15,200 cc/min. – 11,400 cc/min.
IIIC1d
= 3,800 cc/min.
76. A. This patient has a neuromuscular disease; therefore,
monitoring of the patient’s ventilatory status progres- STEP 3: Find the spontaneous VT.
sively for some time is crucial to determining the pos- V̇E
sible onset of respiratory muscle weakness. When V̇T =
severe respiratory muscle weakness presents itself, the f
patient might be on the brink of respiratory failure. 3,800 cc/min.
=
Certain bedside respiratory measurements can be ob- 15 breaths/min.
tained to track the progression of the patient’s disease.
These measurements include the respiratory rate (RR), = 253 cc/breath
MIP, and vital capacity (VC). Lowering the ventilator’s preset rate of 10 breaths/min.
A RR greater than 30 bpm, an MIP below -20 to -25 would be a reasonable approach toward addressing the
cm H2O, and a VC less than 15 ml/kg of ideal body hyperventilation problem.
warrant the onset of respiratory failure. Endotracheal (1:896–897), (10:250–251).
intubation and mechanical ventilation are indicated to
treat respiratory failure.
IIIC1f
Intubation is also indicated to reduce the increased risk of 78. C. IMV is a form of mechanical ventilatory support
aspiration associated with difficulty swallowing. The chest that enables the patient to spontaneously breathe in-
radiograph reveals low lung volumes at this time, which is between receiving mandatory breaths from a ventila-
consistent with a restrictive abnormality. All three of these tor. IMV is frequently used in the ventilator weaning
respiratory measurements were beyond the limit, indicat- process. IMV sometimes appears to afford greater suc-
ing significant respiratory muscle involvement. cess than T-piece trials, which are characterized by al-
(1:543–547), (10:235–236), (15:710). ternating periods of mechanical ventilation followed
by varying lengths of time of spontaneous breathing
IIIC1d via an aerosol T-piece. More, recently, microprocessor-
controlled ventilators provide Pressure Support (PS)
77. C. This patient is experiencing respiratory alkalosis, as
ventilation (used for weaning), which maintains a ser-
indicated by the patient’s acid-base status. He has a
vocontrolled, preset pressure until the inspiratory flow
PaCO2 of 33 torr, which is less than the lower limit of
rate decreases to about 25% of the peak inspiratory
normal (35 torr), and has a pH of 7.49, which is higher
flow rate delivered. The level of PS is gradually re-
than the upper limit of normal (7.45).
duced as the patient assumes a greater amount of the
Because this patient has a spontaneous breathing rate WOB.
of only 4 breaths/min., the ventilator is responsible for
When IMV is used for weaning, the patient’s sponta-
the hyperventilation. Either the SIMV rate is too high,
neous rate must exceed the mandatory rate provided
or the tidal volume is too large. Based on the patient’s
by the ventilator. Although weaning protocols vary
ideal body weight of 90 kg, he is receiving 10.5 cc/kg
from institution to institution, an IMV rate of 10
of IBW, which is at the lower end of the 10–15 cc/kg
breaths/minute or fewer is generally considered a suit-
tidal volume guideline. That is,
able starting point. IMV rates greater than 10 breaths/
950 cc minute usually indicate that the patient might not be
= 10.5 cc/kg ready to assume a greater load of the WOB.
90 kg
The guideline used by the NBRC for establishing a
Therefore, it is inadvisable to lower the patient’s tidal
mechanical ventilator tidal volume is 10–15 cc/kg of
volume to correct the PaCO2. The mechanical ventila-
ideal body weight. Although choice D meets the crite-
tory rate needs to be lowered.
ria for weaning with IMV as stated previously, the
STEP 1: Calculate the mechanical minute ventilation. minute ventilation (V̇E) provided by these settings
would be excessive. That is,
VT  f = V̇E

346 Chapter 5: Therapeutic Procedures

 IMV V̇E Spontaneous V̇E onists include albuterol, metaproterenol, pirbuterol,
terbutaline, and salmeterol.
650 cc 650 cc
 5 breaths/min.  12 breaths/min.
Anticholinergic bronchodilators, e.g., ipratropium bro-
mide (Atrovent), can be used for treating an acute asth-
3,250 cc/min. 7,800 cc/min. matic episode after beta-2 agonists have proved to be
ineffective. Zafirlukast (Accolate) is a leukotriene in-
Total V̇E
hibitor. These types of drugs prevent inflammation and
3,250 cc/min. bronchoconstriction. Nedocromil has similar pharma-
+ 7,800 cc/min. cologic activity to cromolyn sodium and is used to pre-
vent acute allergic bronchospasm.
11,050 cc/min. or
11.05 liters/min.
(1:454–456), (8:103, 128–129, 218–219, 222–224),
(16:1008–1009).

Choice C would provide the patient with an overall IIIC1h

minute ventilation of 8.84 liters/min. That is, 82. D. Numerous criteria are used to assess a patient’s
readiness for weaning from mechanical ventilation.
mechanical V̇ E = 650 cc/breath  4 breaths/min. = 2,600 cc/min.
Table 5-12 lists these criteria.
+ spontaneous V̇E = 520 cc/breath  12 breaths/min. = 6,240 cc/min.

overall V̇E = 8.840 cc/min. Table 5-12: Criteria for weaning from mechanical
ventilation

(1:848, 860–862), (2:528–532), (10:197–198), Physiologic Acceptable

(15:1030–1032). Measurement Values

PaO2 on  40% O2  60 torr

IIIC1g SpO2 on  40% O2  90%
79. A. Proventil and terbutaline are administered in P(A-a)O2 on 100% O2 < 300–350 torr
aerosolized form as bronchodilators. Atropine and spontaneous respiratory rate  25 bpm
ipratropium bromide, which are anticholinergic bron- spontaneous tidal volume  3 cc/kg
vital capacity  10–15 cc/kg
chodilators, can also be administered via the inhalation
MIP  –20 to –25 cm H2O
route. Cromolyn sodium is useful in the prophylactic (for ~ 20 sec)
treatment of certain forms of asthma but it is ineffec- Q̇S/Q̇T < 15%
tive in the treatment of an acute asthmatic episode. VD/VT < 0.55–0.60
Mucomyst itself can induce bronchospasm; therefore,
this drug would be contraindicated.
Other weaning indications include the following con-
(1:574, 577, 579), (2:578, 580, 584, 588), ditions:
(8:102, 214–219), (15:177–182).
• conscious and cooperative patient
• cardiovascular stability
IIIC1g
• resolved underlying problem
80. D. The patient is experiencing some of the side effects
of terbutaline (a -2 agonist). Included among these (1:985), (16:626–630, 1152–1153).
adverse reactions are tremors, nervousness, and anxi-
ety. While these symptoms might be ordinarily seen IIIC2a
with beta-two agonist therapy, another drug should 83. B. Mask CPAP for treatment of refractory hypoxemia
still be substituted to minimize these side effects. can be successfully administered with pressures up to
(1:454–456), (8:117–119), (16:479). 15 cm H2O. Maintaining higher pressures by mask is
difficult. A 5-cm H2O increase in CPAP for this patient
could increase the PaO2 to the desired minimum level
IIIC1g
of 60 mm Hg. CPAP levels are normally increased in 5
81. C. Beta-2 adrenergic bronchodilators are the most ap- cm H2O increments. The high FIO2 indicates that fur-
propriate medications to administer to an asthmatic ther increases in oxygen will probably not be effective.
who is experiencing an acute attack. These medica- The arterial blood-gas results reveal that the patient is
tions are among the first-line drugs to be given during still maintaining adequate alveolar ventilation and does
an acute asthmatic episode. The intended purpose of not need mechanical ventilatory support at this time.
these drugs is to produce bronchodilatation. Beta-2 ag-
(1:783, 865), (10:267–268), (15:733).

Chapter 5: Therapeutic Procedures 347

IIIC2b IIIC2c
84. D. PEEP is indicated in patients who exhibit refractory 87. D. To facilitate diaphragmatic movement, this patient
hypoxemia. This patient is already receiving a high should be placed in a semi-Fowler position. The semi-
FIO2, which might lead to oxygen toxicity. The blood- Fowler position is described as placing the patient in
gas values reveal hypoxemia and accompanying hy- an inclined position with the upper half of the body
perventilation. Attempting to treat the respiratory raised by elevating the head of the bed approximately
alkalosis will be futile without first treating the hypox- 30 degrees.
emia that is the probable cause of the acid-base imbal-
The pain caused by the abdominal surgery experienced
ance. This situation is a classic one requiring the use of
by this patient also restricts diaphragmatic excursion
end-expiratory pressure. A minimum of 5 cm H2O of
(and therefore, chest-wall expansion). To optimize
PEEP, followed by re-evaluation of the oxygenation
ventilation, the patient should be positioned to enable
status, is indicated. Increasing the PEEP as tolerated to
the diaphragm to move as much as possible. Reverse
obtain a PaO2 of at least 60 mm Hg with an FIO2 of
Trendelenburg, supine, and lateral positions restrict di-
less than or equal to 0.50 is the ultimate goal. Sedating
aphragmatic movement.
the patient is inappropriate when agitation is caused by
hypoxia. (9:61–62), (16:171, 218).
(1:865, 879–880), (2:545), (10:267–268), (15:724).
IIID1
IIIC2b 88. C. Fluoroscopy provides dynamic pictures of the tho-
rax during inspiration and exhalation. Fluoroscopy is,
85. D. This patient meets the criteria for weaning from
therefore, the best radiographic technique for studying
PEEP. Generally, a patient can have PEEP decreased
diaphragmatic activity.
when he can sustain an arterial PO2 of 80 torr or more
on an FIO2 equal to or less than 0.40. PEEP levels are (15:616–617), (16:191).
generally reduced by 5 cm H2O increments during
weaning from PEEP. A fall in the PaO2 of 20% or more IIID2
suggests the need to increase the PEEP to its previous 89. A. Acute alveolar hyperventilation (also called acute
level. A patient might be disconnected from the venti- respiratory alkalosis) is indicated by the arterial blood-
lator or extubated from PEEP levels of 5 cm H2O or gas results. The patient has inhaled carbon monoxide,
less without adverse reactions in most cases. 5 cm H2O as inferred from the scenario associated with this ques-
can easily be applied by mask to patients who still tion. Carbon monoxide molecules have a greater affin-
need it to improve oxygenation, however. ity for hemoglobin and will block oxygen from
(10:284–285), (15:733–734). bonding with the hemoglobin. This patient should
have a carboxyhemoglobin (COHb) level measured to
IIIC2b determine the amount of carbon monoxide bound to
her hemoglobin. 100% oxygen should be administered
86. D. Because the pH and the PaCO2 are both within
to this patient until the carboxyhemoglobin level is
normal limits and the patient’s spontaneous ventila-
within the normal range, i.e., 0.5% COHb for non-
tory rate is not excessive, the patient is maintaining
smokers. Smokers generally have a COHb% around
adequate ventilation. In general, ventilation is being
5% to 10%.
achieved with satisfactory efficiency if an adult patient
is able to maintain a normal or low arterial PCO2 with (1:272–273), (9:115), (16:261).
a minute ventilation less than 10 liters/minute. Addi-
tionally, there should be no clinical signs of respiratory IIID2
muscle fatigue, such as dyspnea, tachypnea, and asyn- 90. B. The exact nature of injury is unknown at this time.
chronous or paradoxical breathing. Therefore, a chest radiograph must be obtained imme-
The PaO2 value is low, however. Because the FIO2 is diately to determine the extent and nature of the chest-
already at the upper limit of the acceptable range for wall injury. Blunt chest-wall trauma can cause mild
weaning, an increase in the CPAP level is indicated in chest-wall injury and flail chest with or without pneu-
this patient, who is probably exhibiting hypoxemia mothorax. Other associated complications include
caused by postoperative atelectasis. The patient is in pulmonary contusion and hemothorax.
stable condition and is capable of breathing sponta- The patient in this question is described as having
neously. A longer trial on CPAP with an increased paradoxical chest-wall movement on the right side of
level of end-expiratory pressure would be beneficial, the thorax. The implication is that the patient has flail
however. chest—a double fracture of two or more adjacent ribs.
(1:783, 865), (10:267–268), (15:857, 900–901). This segment will bulge away from the rest of the

348 Chapter 5: Therapeutic Procedures

 chest wall during exhalation and will be sucked in dur- sis. Whenever the PaCO2 falls below 35 torr and the
ing inspiration. HCO 3̄ ion concentration resides within the normal
range of 22 to 26 mEq/L, the patient is described as
(1:550), (16:178, 222, 1123).
having an acute respiratory alkalosis. The acid-base
disorder is called acute because the HCO 3̄ ion level has
IIID2 not compensated (i.e., decreased) for the decreased
91. C. The normal range for the PaCO2 is 35 to 45 torr. A dissolved carbon dioxide in the arterial blood (PaCO2).
PaCO2 greater than 45 torr signifies hypoventilation.
This patient has a PaCO2 of 52 torr. Therefore, this pa- This patient is also said to have refractory hypoxemia,
tient is experiencing hypoventilation. Because the me- which results from the attempted ventilation of col-
chanical ventilator is in control mode, the ventilator lapsed alveoli receiving pulmonary capillary blood
settings are responsible for this patient’s hypoventila- flow. Alveoli receiving perfusion but not ventilation
tion. The minute ventilation (V̇E), which is a product are called shunts. Increasing the FIO2 does not correct
of the respiratory rate (f) and the tidal volume (V̇T), is the hypoxemia caused by shunting. Consequently, this
too low to match this patient’s carbon dioxide produc- patient also has hypoxemia that is uncorrected by oxy-
tion level. gen therapy (i.e., refractory hypoxemia).

The tidal volume is usually established based on the Based on the alveolar air equation, this patient’s PaO2
guideline of 10–15 cc/kg of ideal body weight. This should be higher than 52 torr while breathing an FIO2
patient’s ideal body weight is 80 kg. Therefore, he is of 0.40. That is,
within the guideline just mentioned. In fact, he is re-
ceiving a tidal volume of 11.4 cc/kg (900 cc  80 kg).
Based on this information, his VT is sufficient. A ven-
PAO2 = (PB – PH2O) FIO2 – PaCO2 FIO2 + ( 1– FIO2
R
)
tilatory rate of 8 breaths/minute is rather low. This rate
should be in the range of 10 to 12 breaths/minute.
Therefore, this ventilator setting is responsible for the
(
= (760 torr – 47 torr) 0.4 – 30 torr 0.4 +
1– 0.4
0.8
)
patient’s hypoventilation. = (760 torr – 47 torr)0.4 – 30 torr (0.40 + 0.75)
The CRT must, however, keep in mind that the patient = (760 torr – 47 torr) 0.4 – 30 torr (1.15)
here suffers from status asthmaticus. By increasing the
rate, the expiratory time shortens. A shortened expira- = (713 torr) 0.4 – 34.5 torr
tory time could cause auto-PEEP and worsen the CO2 = 285 torr – 34.5 torr
retention. The CRT must recall that most CO2-rich gas
is exhaled near end-expiration. Therefore, an adequate = 250.5 torr
expiratory time must be maintained. With a PAO2 well over 200 torr, one would expect the
The following formula can be used to achieve a target PaO2 to be at least 200 torr. The fact that this patient’s
PaCO2 for patients who are mechanically ventilated in PaO2 is only 52 torr despite receiving an FIO2 of 0.40
the control mode: indicates refractory hypoxemia.

When keeping the VT constant and changing the f to (1:232–233, 272–273), (9:106–108, 115),
achieve a target PaCO2, use the following formula: (17:47, 50, 131–132, 265).

(known PaCO2)(known f)
desired f = IIID3
desired PaCO2 93. D. Pulse oximeters used in patient-care situations use
When keeping the f constant and changing the VT to only two wavelengths of light. The two wavelengths are
achieve a target PaCO2, use the following formula: red and infrared; these wavelengths detect oxyhemoglo-
bin and deoxyhemoglobin, respectively. Hemoglobin
(known PaCO2)(known VT) combined with carbon monoxide, called carboxyhe-
desired VT =
desired PaCO2 moglobin (COHb), absorbs the same wavelength as
oxyhemoglobin. Therefore, a pulse oximeter cannot
(1:932–933), (10:250–251), (17:35–38). descriminate between oxyhemoglobin and carboxyhe-
moglobin. The consequence is someone who has had
IIID2 CO exposure will demonstrate a higher-than-actual
92. A. This patient is experiencing increased alveolar ven- SpO2 (oxygen saturation via pulse oximeter). Again, the
tilation, causing the PaCO2 to fall below the lower reason is because the pulse oximeter does not detect
limit of normal—thus producing a respiratory alkalo- COHb distinctly from O2Hb. A pulse oximeter is

Chapter 5: Therapeutic Procedures 349

 generally appropriate in all of the other clinical situa- IIID5
tions given in the question. 97. B. Guillain-Barré syndrome is a neuromuscular dis-
(AARC Clinical Practice Guidelines for Pulse ease that affects the peripheral motor and sensory
Oximetry), (1:358–362), (5:298–299), (9:267–268), nerves and frequently follows a viral infection. The de-
(13:191–195), (16:310–312). myelination characteristic of this disorder is usually
self-limiting and reversible. When the muscles of ven-
IIID4 tilation are affected, the patient generally requires in-
tubation and mechanical ventilation. The patient in this
94. B. Patients who do not respond to nebulized hyper-
question has a rapid deterioration in his bedside pul-
tonic saline via small-volume nebulizers should have
monary function measurements. Therefore, this patient
ultrasonic therapy prescribed. Patients who have had
is in eminent danger of respiratory arrest. An appro-
no previous pulmonary disease are good candidates for
priate recommendation at this time would be to intu-
ultrasonic nebulization, because the risk of bron-
bate and mechanically ventilate him. The vital
chospasm is reduced.
capacity should be of special interest to the CRT who
(1:677, 698), (15:803). is dealing with a patient who has a history of Guillain-
IIID4 Barré syndrome. The vital capacity is indicative of the
patient’s ability to ventilate a volume of air in and out
95. D. Streptococcus pneumoniae is the most common of the lungs. Patients who have Guillain-Barré have
cause of bacterial pneumonia. Streptococcal pneumo- difficulty maintaining an adequate vital capacity and
nia characteristically causes sputum to appear purulent tidal volume. In fact, a decrease in the vital capacity
(thick, viscous and colored) with pink or streaks of often precedes blood-gas and acid-base deterioration.
blood running through it. Purulent and bloody sputum
are often seen in pneumonia patients until they are The MIP reflects ventilatory muscle strength. Nor-
treated and recovered. Frothy sputum is seen in pul- mally, the MIP ranges between –80 to –110 cm H2O.
monary edema. Mucoid sputum is most frequently Patients whose MIP falls to less than or equal to –25 cm
seen in chronic bronchitis with no acute exacerbation. H2O have difficulty maintaining adequate spontaneous
When the patient recovers, sputum production and ventilatory efforts.
quality should return to what is typical for his disease (1:545), (2:312), (10:235–236), (16:1052–1053).
state (i.e., chronic bronchitis—mucoid).
(1:299), (9:25–26). IIID6
98. A. The pressure/volume loop shown in Figure 5-7 in-
IIID5 dicates that the patient needs to develop a –2 cm H2O
96. B. Cheyne-Stokes breathing is a periodic ventilatory pressure effort to initiate an assisted breath.
pattern characterized by a gradual increase in depth
and rate, followed by a tapering of rate and depth—of- 1,000
ten with periods of apnea interspersed. This abnormal- 900
ity has been referred to as a waxing and waning of 800
Volume (ml)

respirations. Cheyne-Stokes is often associated with 700

injury to the central nervous system and lesions that 600
result in increased intracranial pressure, although it 500
can also be seen in patients who have congestive heart 400
failure, uremia, drug-induced respiratory depression, 300
patients who are sleeping at a high altitude, and in 200
100
sleeping children.
The cause of Cheyne-Stokes breathing is not well un- -10 0 10 20 30 40
derstood, although a number of factors—including en- Pressure (cm H2O)
hanced ventilatory response to carbon dioxide and
disordered cerebral blood flow—have been suggested. Figure 5-7: Pressure-volume waveform from a patient who
is receiving assist/control ventilation.
Although the pattern of breathing in Cheyne-Stokes
respiration is striking, arterial blood-gas abnormalities
The area to the left of the origin shows the degree of
are not necessarily present. Respiratory alkalosis in
spontaneous inspiratory effort the patient is required to
this condition, however, is a poor prognostic sign.
generate to obtain a breath from the ventilator in the
(1:290, 308), (9:225), (16:167, 304, 1045). assist/control mode.

350 Chapter 5: Therapeutic Procedures

 If the smaller pressure-volume loop resided to the right is, inspiratory time should be approximately half as
of the origin, the sensitivity control would need to be long as expiratory time. This ratio more closely ap-
adjusted to make inspiration more difficult. The ab- proximates the time that is associated with normal
sence of the smaller loop signifies controlled mechan- spontaneous ventilation.
ical ventilation (refer to Figure 5-8).
Certain clinical conditions, however, such as adult res-
piratory distress syndrome (ARDS), indicate inverse
1,000
ratio ventilation (IRV). The intent of IRV for treating
900
ARDS is to elevate the mean airway pressure to im-
800 ion
Volume (ml)

700 ala t prove patient oxygenation. The risks of barotrauma

h
and cardiovascular embarrassment must be considered
Ex
600
500 when IRV is applied.
400 n
ti o
(1:859, 876, 887, 904), (10:215),
300 a
p ir (16:164, 1120, 1150).
200 I ns
100
IIID7
-10 0 10 20 30 40 101. D. Changes in the FIO2 greatly impact the arterial PO2.
Pressure (cm H2O) An increase in mean airway pressure will usually in-
crease the PaO2. Shifting the I:E ratio will influence
Figure 5-8: Pressure-volume loop representing controlled the time the gas mixture is in contact with the alveolar-
mechanical ventilation (note the absence of a small loop).
capillary membrane, therefore impacting the arterial
PO2. Increases and decreases in the tidal volume affect
(10:48–49).
mean airway pressure and carbon dioxide elimination—
and, by virtue of Dalton’s law, will affect the PaO2.
IIID7 Therefore, these factors also influence the arterial PO2.
99. B. A time-cycled ventilator delivers gas to a patient for
a preset time. The description pressure-limited refers (1:912–913), (2:468–486), (10:144, 257, 264),
to a ventilation system where flow causes airway pres- (15:992–994).
sure to increase. If the pressure limit is achieved before
the end of inspiration, a portion of the remaining de- IIID7
livered flow is released through relief valves. Again, 102. C. The disconnect alarm is one of the most important
inspiration does not terminate; rather, gas continues to alarms on the ventilator. This alarm alerts the CRT to
flow from the ventilator. Most of the remaining flow- a patient who has been disconnected from a ventilator.
ing gas is vented to the atmosphere, however, through Although a variety of descriptions have been applied
pressure-relief valves. A ventilator that uses time as the to this alarm, the function produces essentially the
cycling mechanism and pressure as the limiting factor same end. Both the low pressure and low exhaled vol-
is called time-cycled, pressure-limited. ume alarm will sound when the patient has become
disconnected. The peak pressure alarm sounds on
All time-cycled, pressure-limited ventilators enable
high-pressure maximums, while the minimum minute
the CRT to control the inspiratory time. For such ven-
ventilation alarm will sound for reasons other than
tilators that have a ventilatory rate setting, alterations
complete disconnections and might be delayed be-
in the inspiratory time will not influence the ventila-
yond a reasonable time period in the case of discon-
tory rate but will change the I:E ratio.
nection.
For example, lengthening the inspiratory time will not
(1:854–855), (2:484), (10:229, 313–315).
change the frequency of breathing, but it will increase
the I:E ratio. The converse of this statement is also
IIID7
true.
103. C. Because the PIP is the maximum pressure devel-
(1:844–845), (10:79–80, 84). oped in the system and plateau pressure (Pplateau) is the
static system pressure, the difference between these
IIID7 two values reflects the amount of pressure necessary to
100. D. A high I:E ratio (e.g., inspiratory time greater than maintain gas flow. In other words, this pressure differ-
expiratory time) would maintain a higher-than-normal ence represents the pressure that was generated to
mean intrathoracic pressure for a longer time. As a overcome airway resistance. Another term used to de-
consequence, the potential for a decreased venous re- scribe this pressure is transairway pressure. This pres-
turn is greater than with a higher I:E ratio. Generally, sure can be calculated by subtracting the plateau
the I:E ratio used for PPMV should be about 1:2; that pressure from the PIP. For example,

Chapter 5: Therapeutic Procedures 351

 PIP – Pplateau = pressure generated to overcome For example, if the f was 12 breaths/min. and the VT
airway resistance (PRaw) was 900 cc, the V̇E (12 bpm  0.9 L) would be 10.8
L/min. For the %TI to be 50%, the V̇I would need to be
46 cm H2O – 38 cm H2O = 8 cm H2O
21.6 L/min. That is,
(1:938), (2:519–521), (10:37, 258).
10.8 L/min.
%TI =  100
IIID7 21.6 L/min.
104. C. Static compliance (Cstatic) is calculated according to = 50%
the following formula: To decrease the %TI to 25%, any of the following ac-
VT tions can be taken:
Cstatic = (1) INCREASE THE V̇i TO 43.2 L/MIN.
Pplateau – PEEP
Solving for the tidal volume (VT), the equation be- 10.6 L/min.
%TI =  100
comes: 43.2 L/min.
VT = (Cstatic)(Pplateau – PEEP) = 25%
Inserting the known values into the equation, the VT is (2) DECREASE THE Vt TO 460 ml.
calculated as follows:
10.8 L/min.
VT = (25 ml/cm H2O)(25 cm H2O – 5 cm H2O) %TI =  100
21.6 L/min.
= (25 ml/cm H2O)(20 cm H2O) 5.52 L/min.
= 500 ml =  100
21.6 L/min.
The formula for the dynamic compliance (Cdyn) is: = 25%
VT (3) DECREASE THE f TO 6 bpm.
Cdyn =
PIP – PEEP 900 cc  6 bpm
%TI =  100
(1:937), (10:36, 257–258, 274), (16:319–320). 21.6 L/min.
5.4 L/min.
IIID7 =  100
21.6 L/min.
105. C. The inspiratory-expiratory (I:E) ratio alarm acti-
vates when the inspiratory time (TI) equals or exceeds = 25%
50% of the total cycle time (TCT). The following for-
Realistically, increasing V̇I is likely the best option,
mula shows how the inspiratory time percent can be
compared to decreasing either the VT or the f. By de-
calculated:
creasing either the VT or the f, the V̇E might be insuffi-
V̇E cient to meet the patient’s ventilatory demands.
%TI =  100
V̇I (1:860), (17:51).

where, IIID7
%TI = inspiratory time percent 106. C. A ventilator that is time-cycled uses time to termi-
V̇I = mean inspiratory flow rate nate inspiration and to enable exhalation to begin. The
V̇E = minute ventilation (V̇T  f) term volume-limited means that the volume of gas to
Keep in mind that the peak flow (the ventilator setting) be delivered can be preset.
and the mean inspiratory flow rate (V̇I) are not syn- A constant-flow generator is a ventilator that generates
onymous. With a square waveflow pattern, however, a high pressure inside the ventilator, thereby producing
the peak flow and the V̇I will be approximately equal. a flow pattern that does not alter regardless of chang-
If a descending flow-wave pattern is used, increasing ing patient lung characteristics (compliance and air-
the peak flow also increases the V̇I (but not equally). way resistance). This type of ventilator produces a
Based on the preceding formula, the %TI can be de- constant-flow, square wave pattern.
creased by either (1) increasing the V̇I, (2) decreasing The formula to use to calculate the volume delivered
the V̇E by decreasing the VT, or (3) decreasing the VE by a time-cycled, volume-limited, constant-flow gen-
by decreasing the f. erator is shown as follows:

352 Chapter 5: Therapeutic Procedures

 VT = TI  V̇I X = 6.1 liters/minute
where, Approximately 6 liters/minute of room air are en-
trained.
VT = tidal volume (liters)
TI = inspiratory time (seconds) STEP 3: Calculate the total or delivered flow rate
V̇I = flow rate (liters/minute) (V̇DEL).
STEP 1: Convert the inspiratory flow rate to liters/ Therefore, from Step 1,
second.
V̇DEL = V̇S + V̇ENT
60 liters/minute
VI = = 10 liters/minute + 6 liters/minute
60 sec./minute
= 16 liters/minute
= 1 liter/second
A Puritan-Bennett all-purpose nebulizer operating at
STEP 2: Calculate the delivered tidal volume in liters. 10 liters/minute, delivering an FIO2 of 0.70, will pro-
vide a total flow of 16 liters/minute.
VT = TI  V̇I
(1:753), (17:281–284).
= (1.2 seconds)(1 liter/second)
= 1.2 liters IIID8
(1:860), (10:206, 358–359). 108. C. The air-oxygen ratio can be computed as follows:
air flow rate 6 liters/min. 0.6
IIID8 = = = 0.6:1.0
107. D. The following equation states that the product of oxygen flow rate 10 liters/min. 1.0
the concentration and flow rate of the source gas, plus (1:753), (17:281–284).
the product of the concentration and flow rate of the
entrained room air, equals the product of the concen- IIID9
tration and flow rate of the delivered gas.
109. A. Steadily increasing cuff volumes necessary to
(CS  V̇S) + (CENT  V̇ENT) = (CDEL  V̇DEL) maintain a specific cuff pressure might be indicative of
where, tracheomalacia (tracheal dilation). Pressure on the tra-
cheal wall will become excessive in low-pressure de-
CS = concentration of the source gas (%) signs when the cuff is continually stretched to fill the
V̇S = flow rate of the source gas (liters/minute) trachea. Standard high-residual volume (low-pressure)
CENT = concentration of the entrained gas (%) cuffs are designed so that even when they are inflated
V̇ENT = flow rate of the entrained gas (liters/minute) and are in contact with the tracheal wall, in most cases,
CDEL = concentration of the delivered gas (%) they still will be somewhat wrinkled and not fully dis-
V̇DEL = flow rate of the delivered gas (liters/minute) tended. Under these circumstances, the intracuff pres-
The following steps outline how to determine the total sure is equal to the cuff-to-tracheal-wall pressure.
or delivered flow: Therefore, for an increase in volume, there will be a
small increase in pressure. If the cuff becomes com-
STEP 1: Establish the symbols for the unknown val- pletely distended, however, an additional volume of air
ues. Because V̇DEL = V̇S + V̇ENT, therefore, will cause a sharp rise in the cuff pressure.
V̇S = 10 liters/minute Malacia is defined as an abnormal softening of tissues.
V̇ENT = X liters/minute In tracheomalacia and tracheal dilation, increasing cuff
volumes are required to reach minimal occlusive vol-
V̇DEL = 10 liters/minute + X liters/minute ume for the same pressure level. An increasing cuff
STEP 2: Insert the known and unknown values into pressure while the cuff volume remains constant is
the formula. usually indicative of swelling around the cuff.

(100% O2  10 liters/minute) + (21% O2  X liters/minute) (1:604–605, 609), (2:429), (9:224).

= 70% O2 (10 liters/minute + X liters/minute)
IIID10
1,000 + 21X = 700 + 70X 110. C. A pleural friction rub occurs when the two pleural
1,000  700 = 70X –21X layers rub together with more friction than normal. An
increase in friction might be caused by irritation or in-
300 = 49X

Chapter 5: Therapeutic Procedures 353

 flammation. The resulting sound is a creaking or grat- IIIE1d(2)
ing type of sound as the inflamed and roughened edges 113. D. The patient is recovering from an acute asthmatic
rub together during breathing. Pleural rubs often sound episode and is inhaling aerosol particles from a large-
similar to coarse crackles but are not affected by volume nebulizer. Aerosol particles can induce bron-
coughing. The intensity of pleural rubs might increase choconstriction and impair mucociliary transport.
with deep breathing. The pleural rubs can be heard Because each aerosol particle is a potential bron-
only during inhalation but are often identified during choconstrictive agent to patients who have asthma, a
both phases of breathing. large-volume nebulizer is contraindicated. Therefore,
(1:314–315), (9:66–67), (16:174). a heated humidification system operating off a high
flow of oxygen is more appropriate.

IIIE1c The complications and hazards of aerosol therapy in-

clude the following:
111. C. Late inspiratory crackles are often audible in pa-
tients who have either atelectasis, pneumonia, pul- • bronchospasm
monary edema, or fibrosis. The late inspiratory • noscomial infection
crackles, the diminished breath sounds, the dyspnea, • airway burns
and the increased respiratory and heart rates are in- • drug-related, adverse responses
dicative of atelectasis. • ineffective airway hydration
Incentive spirometry is indicated for a patient such as (1:687–688), (16:444–445).
this one, because she is conscious and oriented. The
frequency of the previous order of incentive spirome- IIIE1f
try was much too low. This patient would probably 114. D. The Trendelenburg position involves placing a pa-
benefit from incentive spirometry administered more tient in a head-down position with the patient’s legs el-
frequently. evated at an angle of 45 degrees. In such a position,
Based on the fact that normal adults have a sigh rate of more blood will gravitate to the head, raising the cere-
approximately six times per hour, incentive spirometry bral vascular pressure (i.e., intracranial pressure). This
orders should require at least five to 10 sustained max- position is contraindicated for the following reasons,
imum inspirations per hour. as stated in the AARC Clinical Practice Guidelines for
Postural Drainage Therapy:
(1:312, 314, 774, 777), (9:62, 65–66).
Contraindications for the Trendelenburg Position
• intracranial (cerebral vascular) pressure greater than
IIIE1d(2) 20 torr
112. B. When a patient is attached to a T-piece (a Briggs • uncontrolled hypertension
adaptor), a mist must continuously emerge from the • distended abdomen
distal tip of the reservoir tubing during both inspiration • recent gross hemoptysis related to surgical or radia-
and exhalation. This condition indicates that the tion treatment lung carcinoma
source-gas flow is meeting the patient’s inspiratory de- • avoidance of increased intracranial pressure (e.g.,
mands. If insufficient gas flow is being delivered to the neurosurgery, aneurysms, and eye surgery)
patient, the mist will disappear from the distal end of • uncontrolled risk for aspiration (NG tube feeding
the reservoir tubing each time the patient inspires. In for a recent meal)
that situation, the source gas (oxygen) flow rate must • esophageal surgery
be increased to meet the patient’s inspiratory flow-rate (1:796–801), (16:512–516).
needs.
Increasing the FIO2 reduces the room air entrainment, IIIE1i(1)
which in turn decreases the total delivered flow and 115. B. When implemented properly, an inflation hold has
aerosol output. several physiologic advantages: (1) improves gas dis-
tribution among alveoli having different time con-
Removing 50 cc of reservoir tubing might allow some
stants, (2) improves oxygenation, (3) decreases the
degree of room air dilution, thus lowering the FIO2.
VD/VT ratio, and (4) decreases the arterial PCO2.
The source gas flow rate does not need to be increased,
because the patient’s inspiratory demands are being Mechanically, an inflation hold will
achieved.
• increase the total inspiratory time
(1:755–757), (5:168). • decrease the total expiratory time
• increase mean airway pressure

354 Chapter 5: Therapeutic Procedures

 The mean airway pressure (P̄aw) represents the aver- IIIE1i(1)
age pressure in the airways throughout the entire ven- 117. B. Endotracheal suctioning is associated with a variety
tilatory cycle. The formula for mean airway pressure is of hazards and complications. According to the AARC
P̄aw = [(PIP  PEEP)TI/TCT + PEEP. Clinical Practice Guidelines for Nasotracheal Suction-
(1:323, 845, 879), (10:85, 145), (15:651), (16:686, 687). ing, they include the following:
• hypoxia/hypoxemia
IIIE1i(1) • cardiac or respiratory arrest
116. D. Despite the fact that volume-control ventilation • nasal, pharyngeal, tracheal trauma or pain
consistently delivers a preset volume and minute ven- • cardiac dysrhythmias or bradycardia
tilation when lung compliance and/or airway resis- • pulmonary atelectasis
tance changes, barotrauma becomes a serious threat as • bronchoconstriction or bronchospasm
peak inspiratory and alveolar distending pressures in- • gagging/vomiting
crease. This situation places the patient at increased • uncontrolled coughing/laryngospasm
risk for developing barotrauma (i.e., pneumothorax). • increased intracranial pressure
• pressure
In the pressure-control ventilation (PCV) mode, the me-
chanical ventilator delivers a constant level of pressure The cardiac dysrhythmia displayed on the ECG moni-
to the patient’s lungs. The CRT presets the pressure, res- tor in Figure 5-9 is sinus tachycardia.
piratory rate, inspiratory time (or I:E ratio), and sensi-
Although not a life-threatening ECG pattern itself, si-
tivity. The tidal volume the patient receives, however,
nus tachycardia can deteriorate into ventricular tachy-
depends on the lung compliance and/or airway resis-
cardia, which requires defibrillation.
tance, as well as the preset pressure. The PCV mode is
frequently used when the PIP or Pplateau meet or exceed To try to alleviate this problem, the CRT needs to im-
35 cm H2O during the volume-controlled mechanical mediately withdraw the suction catheter and hyperox-
ventilation mode. ygenate the patient. Tachycardia associated with
endotracheal suctioning is thought to be caused by hy-
In this question, the CRT is requested to protect the pa-
poxemia or sympathetic excitation.
tient from high peak inspiratory pressures, which gen-
erally translates into elevated intrathoracic pressure. Bradycardia can also develop from endotracheal suc-
The PCV mode is effective in this situation. tioning and is caused by vagal stimulation or hypoxemia.
In such cases, the suction catheter must be immediately
IRV raises the mean airway pressure (P̄aw) by having
withdrawn and followed by hyperoxygenation.
an inspiratory time longer than the expiratory time.
Peak inspiratory pressure and alveolar distending pres- Removing the catheter immediately and reconnecting
sure would also increase. The IRV mode requires se- the patient to the mechanical ventilator might not be
dation and paralysis. entirely inappropriate. The mode of ventilation, FIO2,
and respiratory rate, however, influence the wisdom of
Pressure-support ventilation (PSV) requires the patient
that action.
to spontaneously breathe and receive pressure augmen-
tation (preset by the CRT) with each spontaneous breath. (1:619–620), (16:900–903).
The patient determines the tidal volume, inspiratory
flow, respiratory rate, and inspiratory time. This mode IIIE1i(1)
would be effective in reducing the PIP. The patient in this 118. D. This patient is receiving an adequate ventilatory
problem is not breathing spontaneously, however. rate and tidal volume. The tidal volume is within the
Assist/control ventilation would accomplish nothing 10–15 cc/kg (IBW) range, i.e.,
different as compared with volume-control ventilation. VT 875 cc
= = 10.9 cc/kg (IBW)
(1:858–860, 875–878), (10:192, 198–200), IBW 80 kg
(16:616–617).

Figure 5-9: Sinus tachycardia.

Chapter 5: Therapeutic Procedures 355

 Because the patient is not breathing spontaneously, nasopharynx. This patient has vocal cord paresis and
pressure-support ventilation is inappropriate. For a tracheal stenosis (a fixed lower-airway obstruction);
moderate COPD (pulmonary emphysema) patient, the therefore, the tube size will be dictated by the smallest
arterial blood-gas values seem reasonable. The PaO2 is opening below the glottis.
acceptable for an FIO2 of 0.30. Therefore, the FIO2
PSV is useful in overcoming the added WOB imposed
should not be increased to 0.40. Increasing the ventila-
by artificial airways, ventilatory circuitry, and demand
tory rate to 14 breaths/min. would cause the PaCO2 to
valves. In fact, PSV can be used to reduce or com-
fall. For a patient who has moderate COPD, a PaCO2
pletely remove the WOB.
of 60 torr is acceptable. This patient’s minute ventila-
tion (V̇E = VT  f, or 875 cc  12 breaths/min. = 10.5 (1:864), (10:85, 199, 214), (16:616, 667–668).
lpm) is 10.5 liters/min. Therefore, no changes are nec-
essary in the ventilatory management of this patient at IIIE1a
this time.
122. C. If a ventilator patient exhibits an MIP of at least –25
(1:823–824, 826–828), (16:1037–1038). cm H2O and a vital capacity greater than or equal to 10
to 15 ml/kg of the patient’s ideal body weight, discon-
IIIE1i(1) tinuance of mechanical ventilation should be consid-
119. A. When weaning an infant from CPAP, the FIO2 and ered. Of course, other criteria should be assessed (for
the PaO2 are often primary considerations. The guide- example, arterial blood gases, ventilatory rate, FIO2,
lines for weaning from CPAP are as follows. The FIO2 vital signs, VD/VT, and Q̇ S/Q̇ T. The VD/VT ratio should
can be decreased by 0.02 to 0.03 (2% to 3%) when the be less than 0.6, whereas the Q̇ S/Q̇ T ratio should be
PaO2 is greater than 70 torr. The CPAP level can be de- less than 0.2.
creased when the PaO2 is greater than 70 torr on an (1:971), (2:186–187, 190–191, 528–533), (10:326–327),
FIO2 of less than 0.40. (15:1020–1022).
Therefore, in this situation, the infant’s FIO2—which
is now 0.70 and is causing a PaO2 of 145 torr—can be IIIE1a
reduced to 0.40 to 0.50. 123. B. Whenever a patient who is receiving positive pres-
(Care of the High Risk Neonate, 3rd ed., Klaus and Fa- sure ventilation complains of chest pain, further eval-
naroff, W. B. Saunders, 1986, p. 205). uation is needed before continuing because of the
possibility of a pneumothorax. Notifying the physician
of this adverse reaction is necessary. The treatment
IIIE1a
should be discontinued until evaluation is completed.
120. D. Beta adrenergic bronchodilators stimulate beta-1 Evaluation that can be conducted at the bedside in-
and beta-2 adrenergic receptors. Therefore, in the cludes auscultation, assessment of vital signs, and
process of exerting their therapeutic effect, beta adren- diagnostic percussion of the chest. While a pneumo-
ergic bronchodilators produce a number of side ef- thorax and barotrauma are uncommon with IPPB, they
fects. These side effects include: tremors, increased are potential complications that could be life-threaten-
blood pressure, tachycardia, palpitations, dizziness, ing in the absence of a functioning chest tube. Reduc-
headache, and nausea. ing the risk of barotrauma is primarily accomplished
If a patient displays any of these adverse effects during by avoiding air trapping in patients who have emphy-
the course of administration of a beta adrenergic bron- sema or a similar obstructive disease. Use of relatively
chodilator, the treatment should be immediately dis- high flow rates to enable extra time for exhalation is
continued and the patient should be monitored. one way to accomplish this goal.
Additionally, the CRT should consider suggesting to (1:781–782), (16:533).
the patient’s physician that a more beta-2 specific
medication be used or perhaps the dosage decreased.
IIIE1a
(1:574–577), (8:102–105, 115–121). 124. A. Although the palpation, percussion, and ausculta-
tion findings are consistent with atelectasis, they are
IIIE1a also the same for a pleural effusion. The results of in-
121. A. One of the major concerns in clinical care is the spection help differentiate the two clinical conditions.
potential for endotracheal tubes to greatly increase the In a pleural effusion (if the accumulated volume is
resistance to air flow. Generally, the largest diameter large enough), the trachea and mediastinum shift away
tube that fits through the patient’s glottis should be from the affected side. In other words, if a sufficiently
used. Nasal intubation usually requires a tube one-half large pleural effusion is located on the right side, the
size smaller, because it must pass through the nose and trachea and mediastinum will shift to the left.

356 Chapter 5: Therapeutic Procedures

 On the other hand, inspection during atelectasis (as- only be accomplished through optimal patient instruc-
suming the atelectatic area is significant) reveals tra- tion and supportive encouragement. Despite the devel-
cheal and mediastinal deviation toward the affected opment of pain when performing incentive spirometry,
side. If the atelectasis is on the right side, the trachea the ideal breathing pattern (i.e., slow, deep, sustained
and mediastinum shift to the right. inspirations) should be maintained. When the patient
consistently achieves the preset inspiratory volume, a
This patient has a left-sided pleural effusion, not atelec-
higher volume goal should be set. Increasing inspira-
tasis. Therefore, hyperinflation therapy is ineffective (not
tory volume goals should be established daily. The
indicated). An upright and then a lateral chest radiograph
CRT must set a goal that is attainable and demanding
will confirm or rule out a pleural effusion. The fluid in
moderate effort. Setting a goal that the patient can
the intrapleural space (if present) will occupy the lowest
achieve easily results in little incentive, causing an in-
area of the lung on an upright film. The fluid level will
effective maneuver.
relocate and reposition itself on a lateral chest film.
After a maximal inspiration, the patient should be in-
(1:37, 307–314, 411–412), (9:60–66), (refer to the ap-
structed to sustain the breath for at least five seconds.
pendix in this text).
The patient should be given the opportunity to rest as
long as necessary before the next inspiratory maneu-
IIIE1b(1) ver. A rest of 30 seconds to one minute might be nec-
125. D. When the terminal flow control on the Bennett PR- essary for some patients and helps avoid a common
2 is operational, the source gas powering the ventilator tendency to perform the maneuver at rapid rates to get
becomes diluted. The terminal flow control is designed their 10 breaths done.
to compensate for minor leaks in the system by permit-
ting air to flow past the Bennett valve to decrease the (Respiratory Care, Dec. 1991, Vol. 36, No. 12, Incen-
flow enough to close the valve. Again, this added air tive Spirometry Clinical Practice Guidelines, pp.
flow dilutes the source gas. 1402–1405), (1:774–776), (16:529–532).

(1:781), (4:224). IIIE1d(3)

129. B. Hypertonic saline is the medication of choice for
IIIE1b(1) sputum induction. The irritant properties of the solu-
126. A. If a patient cycles on a positive-pressure breathing tion promote coughing to assist with the movement of
device by exerting –2 cm H2O pressure, as indicated secretions in the airways. The increased osmolarity of
on the pressure manometer, the patient is assuming hypertonic saline solutions assists with moving fluid
some of the WOB (that is, initiating inspiration). Ac- into the bronchial mucosa.
tually, the patient does not need to exert an inspiratory
effort of greater than –3 cm H2O to initiate inspiration. (1:677), (16:443–444, 1061).
If the patient “pulls” a more negative inspiratory pres-
sure, the sensitivity control should be adjusted. In this IIIE1e(1)
instance, no change needs to be instituted, because 2 130. C. Some chronic pulmonary patients who have in-
cm H2O is not considered exertional for the patient. creased levels of carbon dioxide (hypercapnea) breathe
via their hypoxic drive. IPPB therapy at an FIO2 of 1.0
(1:782), (4:224).
might increase the PaO2 significantly, thereby elimi-
nating the only stimulus (hypoxemia) for breathing.
IIIE1c Patients who breathe via stimulation of their peripheral
127. A. The incentive spirometry goal for this patient needs chemoreceptors (carotid and aortic bodies) generally
to be re-evaluated. If the goal is set too high for the pa- cannot assume an FIO2 greater than 0.30 and develop
tient, she will become discouraged and frustrated. The oxygen-induced hypoventilation. Many chronic CO2
goal needs to be established at a level that will give the retainers exist, however, who can tolerate higher FIO2s
patient a challenge, but the goal must not be unobtain- (e.g., 0.40 to 0.50).
able. As the patient’s condition improves, the goal will
be more easily obtained, and the patient will sense (1:779–782), (15:711, 721, 877–878).
progress is being accomplished. The patient should be
encouraged to do her best throughout the procedure. IIIE1e(1)
131. D. Air-entrainment systems are indicated when the clin-
(1:774–776), (16:529–532).
ical objective is to provide a low-level, stable FIO2 (less
than 0.30). The two most common systems in this cate-
IIIE1c gory are the air-entrainment (Venturi) mask and the all-
128. B. The effectiveness of any hyperinflation therapy is purpose nebulizer. In general, Venturi masks are
dependent on patient cooperation and effort, which can indicated for alert patients who have intact, normal hu-

Chapter 5: Therapeutic Procedures 357

 midification mechanisms. If secretion clearance is not rates because of the sigmoid shape of the oxyhemo-
an issue, the Venturi mask is ideal. Nebulizers, on the globin disassociation curve. Despite this lack of corre-
other hand, are employed to deliver oxygen when either lation, continued use of a pulse oximeter can provide
the upper airway is bypassed or when a humidity deficit important clinical information regarding the patient’s
is contributing to problems with airway clearance. oxygenation problem. What the CRT needs to do in
this situation is change the oxygen-delivery device to a
Low-flow systems, such as the nasal cannula, the
standard nasal cannula and increase the flow rate to 2
simple mask, and the partial rebreathing and non-
liters/min.
rebreathing masks, supply oxygen at flow rates that are
less than the patient’s inspiratory flow demand. The (1:745–746, 748–749, 1114–1115), (16:896–899).
specific level of FIO2 delivered might be high or low,
depending on the patient’s tidal volume and ventila- IIIE1e(3)
tory rate (i.e., the minute ventilation). When a patient 134. A. A standard nasal cannula connected to an E cylinder
breathes more slowly or shallowly than people who of oxygen is suitable for a patient who is relatively sta-
have a normal breathing pattern (VT ~ 500 cc and ven- ble and who has a relatively low activity level with a
tilatory rate ~ 12 breaths/minute), FIO2 levels can be low FIO2 requirement. The patient presented in this
much higher than estimated. Theoretically, the FIO2 question is rather mobile but has low FIO2 needs. At the
delivered via a 6-liter/minute nasal cannula could in- same time, he is often noncompliant with this oxygen
crease from the estimated FIO2 of 0.44 at a tidal vol- therapy, because he does not find the oxygen-delivery
ume of 500 cc to 0.68 if the tidal volume fell to 250 cc. device aesthetically appealing. Consequently, he needs
(Respiratory Care, June 1993, Vol. 38, No. 6, pp. 676 an oxygen-delivery system that affords more mobility
and 678), (1:752–743), (16:390–391). and portability and makes him feel less self-conscious.
A transtracheal oxygen-delivery device connected to a
IIIE1e(1) portable liquid-oxygen unit will satisfy this patient’s
132. A. The lowest possible FIO2 should be used to main- needs. The assumption here is that the patient meets
tain adequate oxygenation in order to minimize the the criteria for a transtracheal oxygen device. These
toxic effects of oxygen on the lung. Generally, an oxy- criteria are as follows:
gen saturation of at least 90% or a PaO2 of at least 60
• Oxygenation is not accomplished via standard ap-
torr with an FIO2 equal to or greater than 0.50 is ac-
proaches.
ceptable. The physiological data obtained suggest that
• Compliance with other oxygen-delivery devices is
the patient is able to tolerate a decreased FIO2 without
low.
compromising oxygenation. An oxygen saturation of
• Preference is given to the transtracheal oxygen-
97% is usually associated with a PaO2 of 90 to 100 mm
delivery device because of cosmetic reasons.
Hg. Decreasing the FIO2 to 0.50 would be the first step
• High degrees of mobility are demanded by the
in the process of optimizing oxygenation. A decrease
patient.
to 0.28 represents too large of an initial change. Such
a change could result in hypoxemia. PEEP might be A demand-flow oxygen-delivery device is associated
indicated if the patient is unable to maintain adequate with technical problems, that is,
oxygenation at a high FIO2.
• not fully reimbursable through Medicare
(1:740, 755–757), (10:160), (16:376, 391). • sometimes poor response times
• sensor malfunctions
IIIE1e(1) • catheter malfunctions
133. C. A reservoir cannula and a pendant nasal cannula are Because this patient has a problem with the cosmetic
oxygen-conserving devices. They are often used with nature of these oxygen appliances, the pendant nasal
liquid-oxygen systems to prolong the supply of oxy- cannula and the demand-flow oxygen devices would
gen in liquid systems for economic reasons. Conse- not be suitable.
quently, lower oxygen flow rates are used with these
oxygen-delivery devices than with standard nasal can- (1:1117–1119), (16:383–385).
nulas. For example, a reservoir nasal cannula at 0.25 to
4 liters/min. can deliver an oxygen percentage of 22% IIIE1e(3)
to 35%, compared to a standard nasal cannula that can 135. B. A compressor-drive humidifier with oxygen bled in
deliver 22% to 45% oxygen at flow rates ranging from at a low flow rate is capable of meeting this patient’s
0.25 liter/min. to 8 liters/min. The pulse oximeter oxygen-delivery needs. Because the patient has been
alerted the CRT to the patient’s hypoxemic level; i.e., recently removed from a post-acute care setting, a
an SpO2 of 85%. When the SpO2 falls below 90%, the higher FIO2 is needed compared to a patient who has
correlation between the PaO2 and the SpO2 deterio- stable COPD and is receiving oxygen at home.

358 Chapter 5: Therapeutic Procedures

 The CRT would need to calculate the air and oxygen placed too high in the trachea, advancing the endotra-
flow rates and analyze the oxygen concentration. The cheal tube about 2 cm will often correct this situation.
formula providing the air and oxygen flow rates is
(1:612).
given as follows:
airflow rate (liters/min.) 100 – O2 IIIE1g(2)
=
oxygen flow rate (liters/min.) O2% – 20 138. C. The expression,

For 40% oxygen, the air and oxygen flow rates would be: content
relative humidity =  100
airflow rate 100  40 capacity
=
oxygen flow rate 40  20 provides for the calculation of the relative humidity
60 when the content is divided by the capacity and the
= quotient is multiplied by 100 to express the ratio as a
20 percentage. Before the calculation can be performed,
3 one must know the amount of water in air saturated at
= 37ºC; i.e., 43.8 g/m3. For example,
1
18 g/m3
The ratio of airflow rate to oxygen flow rate for 40% relative humidity =  100
oxygen is 3 liters/min. of air and 1 liter/min. of oxygen. 43.8 g/m3

(1:753, 1115–1116), (16:894–897). = 0.41  100

= 41%
IIIE1f
(1:90), (2:21), (17:41–42)
136. B. Auscultation of the chest and the chest radiograph
indicate the likely presence of some degree of atelec-
IIIE1g(3)
tasis in the lung bases. The appearance of air bron-
chograms in the same vicinity suggests some alveoli 139. B. When a mechanical ventilator cycles on to inspira-
are fluid-filled and the bronchi leading to them are tion, a tidal volume is delivered, and a PIP is generated
patent. in the process. The PIP is comprised of two compo-
nents: a dynamic component and a static component.
The IPPB treatments at 15 cm H2O for two days have The dynamic component of the PIP represents the
not been effective in helping this patient remove re- pressure developed to overcome airway resistance as
tained secretions or in expanding his lungs to prevent the tidal volume is delivered. The static component
post-operative atelectasis. Alternatively, this patient refers to the pressure generated to keep the lungs in-
might benefit from some form of bronchial-hygiene flated after the tidal volume is delivered.
therapy (i.e., postural drainage, huffing, active-cycle
breathing, or autogenic drainage) combined with hu- If an inflation hold is initiated, the inspiratory pressure
midification, followed by incentive spirometry. This falls from the PIP to the static or plateau pressure. The
regimen is more aggressive than administering IPPB pressure generated to overcome airway resistance
alone. (PRaw) can be calculated by subtracting the plateau pres-
sure (Pplateau) from the PIP. The formula is as follows:
(1:778), (9:159–160, 161–162), (16:509–516).
PRaw = PIP  Pplateau
IIIE1g(1) Certain conditions cause the Pplateau to rise along with
137. C. The combination of decreased or diminished breath the PIP. These conditions include the following:
sounds and the flow of gas through the mouth of an in- • tension pneumothorax
tubated, mechanically ventilated patient often signifies • atelectasis
a problem with the endotracheal tube cuff. Further- • pulmonary edema
more, the ventilator will indicate a decreased tidal vol- • pneumonia
ume and a decreased PIP. • right or left mainstem bronchus intubation
Troubleshooting involves reinflating the cuff and These conditions also cause both the static and dy-
checking the status of the pilot balloon and one-way namic compliance values to decrease.
valve. These clinical presentations also develop when
the endotracheal tube is positioned unusually high in Other conditions cause only the PIP to increase (the
the trachea (i.e., in the vicinity of the glottis or around Pplateau remains constant). These conditions include the
the esophagus). If the endotracheal tube has been following:

Chapter 5: Therapeutic Procedures 359

 • mucous plugging In this situation, however, this patient is receiving a
• bronchospasm tidal volume at the highest level of the recommended
guideline. The guideline for establishing and main-
Mucous plugging and bronchospasm also cause only
taining a mechanically delivered tidal volume is 10 to
the dynamic compliance to fall. The static compliance
15 cc/kg of ideal body weight.
remains constant, because only the Pplateau increases.
This pediatric patient has a body weight of 30 kg,
The patient in this question experienced an elevated
which is 66 lbs (30 kg  2.2 lbs/kg). According to the
PIP with a constant Pplateau. Auscultation of the chest
tidal volume guideline for mechanical ventilation, this
also revealed inspiratory crackles. Therefore, tracheo-
child’s mechanical tidal volume should range between
bronchial suctioning is indicated. Bronchospasm often
300 cc and 450 cc; i.e.,
produces wheezing.
30 kg  10 cc/kg 30 kg  15 cc/kg
(1:937), (9:65–66), (10:257–259). to
300 cc 450 cc
IIIE1h(3) Because this girl’s mechanically set tidal volume is al-
140. C. For children, the recommended suction-pressure ready 450 cc, the secondary approach to this hypoven-
levels generally range from –80 to –100 mm Hg. The tilation problem is to consider the mechanical
settings can be altered, depending on the consistency ventilatory rate. An SIMV rate of 4 breaths/minute is
of the secretions. Thicker secretions might require rather low; in fact, it is generally the point from which
more negative pressure, and thinner secretions might patients are weaned from mechanical ventilation.
require less. Because the amount of negative pressure
is one of many factors contributing to mucosal trauma, Evaluation of this girl’s arterial blood-gas data indi-
limiting the amount of negative pressure within these cates that she is not ready to assume a high degree of
appropriate guidelines is essential—despite maximum spontaneous breathing, because her PaCO2 is 65 torr.
suction pressure capabilities of –200 mm Hg. The reasonable approach at this time is to increase this
patient’s SIMV rate to lower the arterial PCO2.
(1:616), (18:402).
Some clinicians believe maintaining any patient at an
SIMV rate of less than or equal to 4 breaths/minute is
IIIE1i(1)
inappropriate because of the increased WOB imposed
141. C. The high-pressure limit alarm on a volume-cycled by the demand valve at this low level of mechanical
ventilator is normally set at a minimum of 10 cm H2O ventilation. This approach calls for switching to an IMV
above the PIP. The pressure-limit alarm setting (45 cm system, continuous-flow CPAP, or pressure-support ven-
H2O) is inappropriately low. When the alarm is acti- tilation.
vated, the patient does not receive the full tidal vol-
ume. Maintaining hypocapnic ventilation to reduce (1:860–862), (2:509, 527–528), (10:146, 197–198),
intracranial pressure is imperative for this patient. (15:994).
Likewise, reducing the tidal volume to 800 cc would
lower the PIP and could deactivate the alarm. This ac- IIIE1i(1)
tion is undesirable, however. Decreasing the peak flow 143. C. This problem can be solved via several approaches.
rate to 40 liters/minute would decrease the PIP as well The first is to look at the alarms that are being acti-
but would prolong inspiration and reduce the I:E ratio vated. On most volume-cycled ventilators, the I:E ratio
to less than 1:2. alarm is activated when the I:E ratio is equal to or
(1:903–904), (10:311–312), (15:992). greater than 1:1. The peak flow rate, tidal volume, and
ventilatory rate combine to determine the I:E ratio. In-
creasing the peak flow rate will shorten the inspiratory
IIIE1i(1)
time. Ventilator patients typically require inspiratory
142. C. The problem that requires attention here is the inor- flow rates of between 50 and 80 liters/minute.
dinately high arterial PCO2 level and the low pH. This
patient displays an uncompensated respiratory acido- Another approach is more mathematical. In this situa-
sis. Customarily, when a patient who is on SIMV or tion, the set inspiratory flow rate of 20 liters/minute
IMV is being under ventilated, as is the case here, in- will deliver the volume of 800 ml in 2.4 seconds. This
creasing the patient’s tidal volume is the initial consid- calculation is illustrated in the following steps:
eration, because it causes less of an increase in the STEP 1: Convert 20 liters/minute to ml/minute.
mean intrathoracic pressure. Increasing the mechani-
cal ventilatory rate has a greater influence on the mean (20 liters/minute)(1,000 ml/liter) =
intrathoracic pressure. 20,000 ml/minute

360 Chapter 5: Therapeutic Procedures

STEP 2: Use the following formula to calculate the STEP 4:
peak flow rate in ml/second: 60 seconds/minute
= 4.3 seconds
20,000 ml/minute 14 breaths/minute
= 333 ml/second
60 seconds/minute STEP 5:
STEP 3: Divide the tidal volume (VT) by the peak 4.3 seconds  0.96 second = 3.34 seconds
flow rate (V̇I) to determine the inspiratory
STEP 6:
time (TI).
0.96 second 3.34 seconds
VT 800 ml I:E ratio = :
= TI or = 2.4 seconds 0.96 second 0.96 second
V̇ I 333 ml/second
 1:3.5
STEP 4: The total cycle time (TCT) is calculated
by dividing the ventilatory rate (f) into 60 A simple rule of thumb for calculating a peak flow rate
seconds/minute. that will deliver the tidal volume in one second is to
multiply the volume in liters by 60 to convert liters per
60 seconds/minute
= TCT second to liters per minute (0.8 liter/second  60 sec-
f ond/min. = 48 liters/minute). The best way to become
skilled in manipulation of TI, I:E ratios, and peak flow
60 seconds/minute
= 4.3 seconds rates is to practice the various calculations in any com-
14 breaths/minute bination.
STEP 5: Calculate the expiratory time (TE) by sub- Another useful guideline to incorporate into I:E ratio
tracting the TI from the TCT. problems is as follows:
TCT  TI = TE inspiratory flow rate
sum of I:E ratio parts =
4.3 seconds  2.4 seconds = 1.9 seconds minutes ventilation
STEP 6: Determine the I:E ratio. For example, an I:E ratio of 1:2 has a sum of I:E ratio
parts of 3; i.e., 1 + 2 = 3. From the formula, one can
TI T E
I:E ratio = : determine that to adequately maintain an I:E ratio of
TI TI 1:2, the peak flow rate must be three times the patient’s
minute ventilation.
2.4 seconds 2.4 seconds
: = 1:0.79 V̇ I 60 liters/minute
2.4 seconds 1.9 seconds = = 3 (sum of I:E ratio parts)
V̇ E 20 liters/minute
An I:E ratio of 1:0.79 is greater than 1:1. = 1:2 I:E ratio
This situation will activate the I:E ratio alarm, result- Similarly, to provide an I:E ratio of 1:3, the peak flow
ing in air-hunger and anxiety for the patient, breath rate must be four times the patient’s minute ventila-
stacking, and asynchrony between the patient and the tion.
ventilator—which might cause the pressure limit
alarm to sound. (1:854–855, 860), (2:566), (10:206, 311–312,
313–315), (17:22–25, 51).
Increasing the flow rate to 50 liters/minute will
shorten the inspiratory time to approximately two sec-
IIIE1i(1)
onds and will return the I:E ratio to a more acceptable
value of 1:3.5. 144. B. A patient who is experiencing a respiratory acidosis
while receiving mechanical ventilatory support is be-
STEP 1: ing hypoventilated. If this acid-base disturbance arises
(50 liters/minute)(1,000 ml/liter) = while a volume-cycled ventilator is being used, the pa-
50,000 ml/minute tient’s tidal volume should be evaluated first. A tidal
STEP 2: volume no greater than 15 cc/kg of ideal body weight
50,000 ml/minute should be delivered. If that limit has already been
= 833 ml/second achieved, then the ventilatory rate should be increased.
60 seconds/minute
The reason for adjusting the tidal volume first is to
STEP 3: minimize the increase in the mean intrathoracic pres-
800 ml sure. Increasing either the tidal volume or the ventila-
= 0.96 second
833 ml/minute tory rate, however, is accompanied by an increased

Chapter 5: Therapeutic Procedures 361

 mean intrathoracic pressure. Increasing the ventilatory represents WOB loops illustrating the role of PSV in
rate has a greater effect on the intrathoracic pressure, alleviating airflow and elastic resistance to sponta-
however. neous ventilation.
The appropriate adjustment to make if this acid-base Levels of PSV can be titrated to partially load or com-
disturbance developed with a timed-cycled ventilator pletely unload the respiratory muscles. To minimize
would be to increase the inspiratory time. If a respira- the spontaneous WOB (apart from the work required
tory acidosis occurred in conjunction with a pressure- to trigger the ventilator), a PSV level should be set to
cycled or flow-cycled ventilator, the corrective action deliver 10 to 12 cc/kg of ideal body weight. This PSV
would be to increase the cycling pressure. level has been termed PSVmax. Probably the most rea-
sonable method of establishing the PSV level for the
(1:909), (2:527–528), (10:251).
purpose of partially unloading the respiratory muscles
is to choose a level of PSV that provides a targeted
IIIE1i(1) tidal volume and ventilatory rate. In other words, tar-
145. D. Because pressure-cycled ventilators are pressure get a PSV level that establishes a reasonable ventila-
preset, secretions (or any obstruction, for that matter) tory pattern in a given patient. Tachycardia, tachypnea,
would not elevate the inspiratory pressure. The inspi- hypertension, diaphoresis, paradoxical breathing, res-
ratory pressure limit would be met before an adequate piratory alternans, and excessive accessory muscle use
amount of time elapsed, however. The result would be signal cardiopulmonary stress and possible muscle fa-
a decreased inspiratory time, an increased ventilatory tigue. In general, levels between 5 and 15 cm H2O will
rate, a decreased I:E ratio, and a decreased tidal vol- accomplish these goals in most patients. Trying to re-
ume. establish the patient’s baseline ventilatory rate (15 to
25 breaths/minute) and tidal volume (300 to 600 cc) is
Pressure-cycled ventilation should not be confused another sound approach.
with pressure-limited ventilation. Although both of
these forms of ventilation deliver a preset peak airway (1:864), (10:85, 199, 214, 226), (16:617, 667, 1147).
pressure, in the pressure-cycled condition, inspiration
terminates when the preset peak airway pressure is IIIE1i(1)
achieved. In the case of pressure-limited ventilation, 147. B. Respiratory distress syndrome (RDS) is character-
when the preset peak airway pressure is achieved pre- ized by reduced lung volumes caused by a lack of pul-
maturely, it is maintained at that point until either vol- monary surfactant associated with premature birth
ume, flow, or time terminates inspiration. (fewer than 35 weeks’ gestation). Among the patho-
physiologic changes are reduced lung compliance, at-
(1:845), (2:564), (10:79–80, 85–86). electasis, and hypoxemia.

IIIE1i(1) The mean airway pressure (P̄aw) represents a compos-

ite of all ventilator-generated airway pressures. Factors
146. A. A spontaneous respiratory rate of 32 breaths/minute
that comprise the P̄aw are (1) the PIP, (2) PEEP, (3) the
with tidal volumes of less than 300 cc and accessory-
inspiratory time over total ventilatory time, and (4) the
muscle use indicate that the patient’s WOB is signifi-
flow rate or pressure curve.
cant, despite the ability to maintain normal arterial
blood-gas values. Studies indicate that pressure- Any factor increasing the P̄aw also increases oxygena-
support ventilation (PSV) counteracts the WOB im- tion. Increases in the P̄aw, however, also increase the
posed by artificial airways, ventilator circuits, and de- risk of barotrauma. Therefore, the P̄aw should be main-
mand-valve systems. Additionally, PSV can enhance tained at the lowest level capable of maintaining ade-
ventilatory muscle endurance and improve patient syn- quate oxygenation.
chrony and comfort.
(1:888, 912–913), (10:143–144, 264, 285), (16:621).
When PSV is used with SIMV, it is generally used to
overcome the work of demand-valve systems and the IIIE1i(1)
resistance to the ventilator circuit and endotracheal 148. C. When PEEP or CPAP are instituted, the goal should
tube during spontaneous breathing. The amount of be to achieve adequate oxygenation with an acceptable
pressure-support ventilation should be set at a level re- FIO2, without compromising the patient’s cardiovas-
quired to prevent a fatiguing workload on the ventila- cular function. Precise determination of the optimum
tory muscles. The workloads imposed by varying PEEP or CPAP level can be accomplished only when
humidifiers, circuits, and demand valves, however, hemodynamic data, specifically cardiac output (C.O.)
prevent an easy quantification of appropriate levels of and mixed-venous PO2 (Pv̄O2) measurements are
PSV to administer under all conditions. Figure 5-10 available.

362 Chapter 5: Therapeutic Procedures

 Because PEEP therapy increases intrapleural pressure, tient from ventilatory support after 48 to 72 hours.
it can decrease venous return and the C.O., as this pa- Once applied, PEEP is usually not reduced until a sat-
tient demonstrated. The drop in C.O. with increased isfactory PaO2 level is obtained with FIO2s of 0.40 to
PEEP is sometimes referred to as “circulatory preload 0.50. Most clinicians agree that PEEP should be in-
depression” or relative hypovolemia associated with in- creased (or decreased) in increments no greater than 5
creased PEEP. As PEEP therapy is applied, the Pv̄O2 cm H2O. Also, PEEP should be decreased gradually,
should increase if the cardiac output is not adversely af- because rapid withdrawal has been associated with
fected. This phenomenon occurs because oxygen de- worsening of the patient’s condition.
livery increases. If excessive PEEP is applied, the Pv̄O2
When one is weaning the patient from PEEP and FIO2,
will decrease because of the effect of PEEP on the car-
the variable decreased depends on the FIO2 level. If the
diac output, thus decreasing tissue oxygen delivery.
FIO2 level is more than 0.50, decrease the FIO2 before
(1:515), (2:539, 543), (10:272–275). the PEEP. If the FIO2 is 0.50 or less, decrease the
PEEP by 5 cm H2O before further decreasing the FIO2.
IIIE1i(1) (2:549), (10:284–285).
149. A. The patient has a normal acid-base status with hy-
peroxemia. In the near-drowning victim, regeneration IIIE2c
of surfactant and a decrease in pulmonary capillary 150. B. The inspiratory-expiratory ratio calculation is out-
leak will typically result in an ability to wean the pa- lined as follows:

A. B.
Volume

Volume

Pressure Pressure

C. D.
Volume

Volume

Pressure Pressure
Figure 5-10: (A) Normal, spontaneous WOB—trapezoid (shaded area) represents
elastic resistance, and hashed area reflects nonelastic (airway) resistance. (B)
Demonstrates a level of pressure-support ventilation to eliminate airway resistance.
(C) Shows a pressure-support level high enough to eliminate airway resistance and
a portion of the elastic resistance. (D) Illustrates ventilator at a pressure-support
level high enough to eliminate the patient’s total WOB (ventilator assumes all WOB).

Chapter 5: Therapeutic Procedures 363

 STEP 1: Calculate the total cycle time (TCT). (1:828–829, 900, 917, 951–953), (10:153, 155, 227,
245–246).
60 seconds/minute
TCT =
f IIIE1i(1)
60 seconds/minute 152. B. The alarms had been set appropriately for the patient
= when he returned from surgery, while he was still anes-
60 breaths/minute thetized. The patient has begun to awaken, however,
= 1 second/breath and the alarms should now be readjusted to allow for
periods of spontaneous breathing. If he was receiving
STEP 2: Determine the expiratory time (TE) by sub- controlled mechanical ventilation or was sedated and
tracting the inspiratory time (TI) from the TCT. paralyzed in the SIMV mode, the patient’s spontaneous
TE = TCT  TI ventilations would not explain the intermittent alarms,
and the CRT would need to troubleshoot the ventilator.
= 1.0 second  0.6 second
Volume and frequency alarms monitor low VT, low and
= 0.4 second high minute ventilation, and low and high ventilatory
STEP 3: Calculate the I:E ratio. rates. These settings have no predetermined levels, al-
though institutions might provide guidelines. The CRT
TI TE must use his judgment in establishing the settings to
I:E = :
TI TI alert personnel to possible changes in the patient’s
condition. Alarms do not need to be so sensitive that
0.6 second 0.4 second they are constantly sounding and frightening the pa-
: = 1:0.67
0.6 second 0.6 second tient or annoying the personnel.
In the preceding situation, the minimum minute venti-
Because the TI (0.67 second) is greater than TE (0.4 lation that one could expect (without spontaneous ven-
second), the ratio is actually expressed as follows: tilations) can be calculated in the following manner:
1 STEP 1: Convert the exhaled tidal volume to liters.
= 1.5
0.67 720 cc
= 0.72 liter
or 1,000 cc/liter
1.5:1 STEP 2: Calculate the minute ventilation by using the
(1:860), (10:205–206), (17:22–25, 51). following formula:
V̇E = VT  f

IIIE1i(1) where,
151. A. The rationale for employing inverse-ratio ventila- V̇E = exhaled minute ventilation (liters/minute)
tion (inverse I:E ratio) is to prolong the inspiratory VT = tidal volume (liter)
time, thereby raising the mean airway pressure (Paw) to f = ventilatory rate (breaths/minute)
improve oxygenation. Infants who have respiratory
distress syndrome can sometimes be effectively venti- V̇E = (0.72 liter)(8 breaths/minute)
lated with inverse-ratio ventilation. = 5.8 liters/minute
When pulmonary compliance increases, however, the The patient’s spontaneous breaths, however, will in-
ventilation time constant (resistance  compliance) crease the minute ventilation above the minimum 5.8
increases, and the lungs require a longer time to empty. liters/minute. The high alarm should be set to accom-
Therefore, to avoid the development of auto-PEEP, the modate an expected rise in minute ventilation to a rea-
CRT must decrease the I:E ratio. Decreasing the I:E is sonable level; i.e., about 10% above this established
accomplished by reducing the ventilatory rate and/or value, to warn of unexpected rises in minute ventila-
decreasing the inspiratory time. tion. Likewise, the low minute ventilation alarm (or
low tidal-volume alarm) should be set to trigger when
Although inverse-ratio ventilation can improve oxy-
either the tidal volume or minute ventilation falls about
genation, this type of ventilation has fallen into disfa-
10% below the established values.
vor because of the increased risk of barotrauma,
especially bronchopulmonary dysplasia and pul- The high-frequency alarm is set too close to the venti-
monary interstitial emphysema. lator rate and should be increased to accommodate a
reasonable ventilatory rate but still trigger when unac-

364 Chapter 5: Therapeutic Procedures

 ceptable tachypnea occurs. The high-pressure limit problems related to low pressure in the pulmonary cap-
should generally be set at 10 cm H2O above the peak illary bed. The decelerating waveform may be suitable
airway pressure in continuous mechanical ventilation for patients who have poor distribution of ventilation.
or SIMV modes. The high and low oxygen alarms are This application is particularly beneficial if the peak flow
set appropriately for an FIO2 of 0.50. rate is low, and if the inspiratory time is lengthened. The
decelerating flow pattern is theoretically appropriate to
(1:853–855), (10:229, 311–315), (16:621, 676–680).
use with adult respiratory distress syndrome.

IIIE1i(3) (1:851–853), (10:43, 53), (16:321–322).

153. A. The blood-gas analysis demonstrates a partially IIIE1i(2)
compensated respiratory alkalemia. In the assist-control
155. B. When a potential problem is discovered, the first
mode of ventilation, simply lowering the set V̇E (by de-
priority is to assure that the patient is being adequately
creasing the assist/control rate or tidal volume) might
ventilated and oxygenated. In this case, the difference
not result in the desired rise in PaCO2. In this case,
in the PIP and tidal volume (VT) is minimal and would
adding mechanical dead space (VDmech) to the circuit
be considered an acceptable variance on a breath-by-
might be necessary. As rebreathed volume, VDmech in-
breath basis. A significant leak would likely be indi-
creases the inspired partial pressure of CO2, thereby
cated by a 5 to 10 cm H2O drop in PIP or by a loss of
raising the alveolar and arterial CO2 tensions.
100 cc or more in VT per breath.
If the patient has a respiratory alkalemia on assisted
Any defect or malfunction must be corrected once it is
ventilation, decreasing the set (mechanical) ventilatory
detected, however, because the CRT’s goal should be to
rate might have no effect on the patient’s ventilatory
provide virtually 100% reliability of the ventilator’s
rate if the patient is initiating all of the breaths. De-
life-support functions. According to MacIntyre and
creasing the tidal volume might be effective unless the
Day, a circuit leak is considered a Level 2 alarm event
patient just increases his ventilatory rate, thus main-
that under certain circumstances, could threaten the pa-
taining a high minute ventilation.
tient’s safety or life if left uncorrected for a prolonged
In this situation, three alternatives are available. First, period. Because the pinhole leak noted previously is
institute IMV or SIMV or allow the patient to breathe not immediately life-threatening, the patient does not
without receiving a machine breath with every inspira- require immediate removal from the ventilator. In other
tion. Some patients will continue to hyperventilate words, the CRT has time to obtain a replacement circuit
when on IMV or SIMV with VDmech, however. Sec- and prepare for another tubing change.
ond, sedate and paralyze the patient and completely
(Respiratory Care, Sept. 1992, Vol. 37, No. 9, p. 1110).
control the patient’s breathing. Third, add VDmech.
The dead space is added between the endotracheal
IIIE1i(3)
tube and the patient wye connector on the ventilator
circuit. Although nomograms exist to estimate the 156. C. The minute dead-space ventilation can be calcu-
amount of dead space necessary to achieve a given lated by multiplying the dead-space volume (VD) by
PaCO2, most clinicians suggest incremental trials with the ventilatory rate (f).
50 cc segments until the desired PaCO2 is achieved. STEP 1: Convert 83 kg to lb, based on the conversion
Equations for adding VDmech are given in Mechanical of 1 kg equals 2.2 lbs.
Ventilation: Physiological and Clinical Applications,
3rd edition, by Sue Pilbeam, Box A-1, page 434, (Ref- 83 kg  2.2 lb/kg = 182.6 lb
erence #10), and Barnes, Appendix A, “Adjusting Ven- STEP 2: Estimate the amount of anatomic dead space.
tilation to achieve a Desired PCO2” Example 3, page
561, (Reference #7). Guideline: Each pound of ideal body weight equals 1
cc of anatomic dead space.
(1:935), (7:561), (10:434).
183 lb  1 cc/lb = 183 cc VD
IIIE1i(1) STEP 3: Determine the dead-space ventilation (V̇D).
154. C. Clinical data, which involves empirically evaluating (VD)(f) = V̇D
when each particular flow pattern or waveform is best
suited, is lacking. From a cardiovascular and gas- (183 cc)(16 breaths/minute) = 2,928 cc/minute
exchange standpoint, there appears to be no difference or
between the sine wave and square wave flow patterns. 2,928 cc/minute
= 2.93 liters/minute
Speculation regarding the accelerating-flow waveform is 1,000 cc/liter
that this pattern might help patients with circulatory (1:211–213), (10:248, 434), (16:330).

Chapter 5: Therapeutic Procedures 365

IIIE2a the patient could experience panic and possibly suffo-
157. C. Changing the patient to a 28% Venturi mask will cate, depending on the design of the mask. Generally,
decrease the PaO2 of this patient, who is apparently ex- a flow rate of at least 10 liters per minute is needed for
periencing impending apnea secondary to oxygen-in- the initial setup of the mask, with adjustments made to
duced hypoventilation because of the 35% Venturi meet individual patient needs.
mask. Patients who have chronic CO2 retention often (1:750–751), (2:415), (15:882).
have associated hypoxemia while breathing room air.
When hypoxemia and chronic hypercapnia coexist, the IIIE2a
central response to carbon dioxide is sometimes
159. D. A severe COPD patient has considerable CO2 re-
blunted, and the primary stimulus to breathing is me-
tention and significant hypoxemia. These patients
diated through hypoxemic stimulation of the periph-
sometimes breathe via their hypoxic drive, which de-
eral chemoreceptors. This abnormal, primary stimulus
pends on an oxygen stimulus to operate. If patients
to ventilation is known as the hypoxic drive.
breathing via their hypoxic drive are given high con-
In clinical practice, the assumption is sometimes made centrations of oxygen (usually greater than 30%), then
that oxygen at controlled, low concentrations can be they stop breathing, because their only stimulus (low
safely administered to patients who have chronic hy- PaO2) for breathing has been removed. Signs that too
percapnea. While a nasal cannula is an appropriate de- much oxygen is being administered to this type patient
vice to use for the stable COPD patient, a Venturi or air include lethargy and confusion. If a patient who has
entrainment mask is a better choice during acute exac- chronic CO2 retention has been alert and oriented and
erbations. An air-entrainment device enables precise then becomes lethargic, confused, and disoriented as a
oxygen delivery at low FIO2s (less than 0.30), despite result of oxygen therapy, hyperoxemia should be sus-
the changes in the patient’s ventilatory pattern. Studies pected.
have demonstrated, however, that at FIO2s greater than
The patient in this question is likely experiencing this
0.30, accuracy diminishes. For example, at an FIO2
phenomenon. Consequently, the best option available
setting of 0.50, the delivered FIO2 averaged 0.39.
is to lower the FIO2 delivered by the air-entrainment
Changing to a 3-liter/minute nasal cannula is not ad- device to around 0.28. A nasal cannula at 6 liters/min.
vised because of the uncontrollable and widely vari- (~ 44% O2) or a simple mask at 12 liters/min. (~ 50%
able FIO2s delivered by this device. With a slow, O2) would eliminate the patient’s hypoxic stimulus;
shallow ventilatory pattern, the estimated 0.32 FIO2 therefore, these devices are contraindicated here.
level (for 3 liters/minute) will increase significantly.
(1:754–755), (16:381–383, 391–392).
The patient is less anxious, but he is not improving. If
the CRT continues to observe the patient, he will ob-
serve the patient experiencing a respiratory arrest IIIE2c
caused by oxygen-induced hypoventilation. Measure- 160. C. Patients who have myasthenia gravis and are expe-
ment of the peak flow and administration of a bron- riencing a cholinergic crisis often require mechanical
chodilator can be considered, but not until action is ventilation for lengthy periods. During this time, these
taken to correct the impending apnea. patients have their anticholinesterase medication with-
drawn to enable the post-ganglionic acetylcholine re-
(1:740), (2:284), (Respiratory Care, June 1993, Vol. ceptors to resensitize to the medication. The time it
38, No. 6, p. 676). takes the patient’s receptors to resensitize determines
the length of stay on mechanical ventilation. Two to
IIIE2a three weeks is not unusual. The general guideline used
158. D. Unlike most other oxygen-delivery devices, the to base the decision for switching to a tracheotomy
non-rebreathing mask has no set flow rate for correct tube is the need for mechanical ventilation for more
operation. Instead, it is necessary to observe the pa- than 12 days.
tient and to adjust the flow rate so that the bag remains
inflated during inspiration. Adjusting the flow rate in This decision-making process is individualized, how-
this manner is important for several reasons. First, the ever. Each situation and patient must be judged based
patient needs to breathe gas, not from the room but on his own unique set of circumstances.
from the mask, to maintain the highest possible FIO2. (1:543–544, 602).
The primary indication for using this type of mask is to
provide a simple way to deliver a high FIO2 to a spon- IIIE2d
taneously breathing, non-intubated patient for short
periods. Second, the patient could rebreathe exhaled 161. C. A number of approaches to weaning patients from
carbon dioxide if flow rates were not adequate enough mechanical ventilation are available. No one method is
to flush the patient’s expirate from the mask. Finally, accepted as the best, however. Circumstances sur-

366 Chapter 5: Therapeutic Procedures

rounding the patient’s situation will help determine enabling the PSV mode to become more prevalent.
which weaning method to use. The PSV mode helps reduce the WOB as the patient
breathes more spontaneously. The use of SIMV with
The patient described in this question might have a dif-
PSV is widely used for weaning patients from me-
ficult time weaning exclusively in the pressure-support
chanical ventilatory support.
mode. Pressure-support ventilation requires the patient
to have a significant degree of spontaneous ventilation. (1:982–984, 985), (10:329–333),
This patient has a spontaneous breathing rate of only 4 (16:631–633, 1152–1153).
bpm. Her overall minute ventilation (V̇E) is given as
9.1 liters/min. So, with a VT of 650 cc and a V̇E of 9.1 IIIE2d
liters/min. (9,100 cc/min.), her spontaneous breathing 162. A. Patients who suffer from COPD generally experience
rate is calculated as follows: air trapping and hyperinflation. Their ventilation-time
STEP 1: constants (compliance  resistance) are usually high.
Therefore, when these patients are mechanically venti-
V̇E lated, they should (1) receive relatively low tidal volumes
f  VT = V̇E, or f =
VT (7 to 10 cc/kg of IBW), (2) have low inspiratory-expira-
tory ratios (expiratory time greater than inspiratory
9,100 cc/min. time), (3) receive low to no levels of PEEP, and (4) ex-
f=
650 cc/breath perience low peak inspiratory pressures.

= 14 breaths/min. (total ventilatory rate) The lower tidal volumes and the avoidance of high lev-
els of PEEP help maintain a low peak inspiratory pres-
STEP 2: sure and minimize the risk of barotrauma. Having the
ftotal = fspontaneous fmechanical expiratory time exceed the inspiratory time gives the
partially obstructed airways time to empty. These pa-
fspontaneous = ftotal  fmechanical tients have larger time constants; therefore, they re-
= 14 breaths/min.  10 breaths/min. quire longer expiratory times. The prolonged time for
exhalation helps minimize or eliminate auto-PEEP,
= 4 bpm which can cause barotrauma.
With a spontaneous rate of only 4 breaths/min., she Keep in mind, however, that the NBRC uses the range
would likely not wean successfully if pressure-support of 10–15 cc/kg (IBW) as the guideline for determining
ventilation were used alone. a patient’s tidal volume for mechanical ventilation.
Similarly, T-piece trials require substantial sponta- (2:291–293), (10:232–235), (15:716–717).
neous breathing ability on the part of the patient.
Therefore, with a spontaneous ventilatory rate of only IIIE2d
4 breaths/min., she would likely have a difficult time 163. C. The blood gases and clinical information suggest that
weaning via the T-piece method. the patient is tolerating the SIMV mode without diffi-
SIMV with pressure-control ventilation (PCV) pro- culty. When using this mode to wean patients from me-
vides the patient with a constant pressure throughout chanical ventilation, decreasing the ventilatory rate by 2
inspiration. The pressure level, the ventilatory rate, and breaths/minute every one to two hours is desirable while
the inspiratory time (or I:E rate) are preset. As with continuing to monitor the patient. Low SIMV rates are
any form of pressure ventilation, the VT is determined not always tolerated by patients because of the imposed
by the patient’s lung compliance and airway resis- WOB through the ventilator system. For these reasons,
tance. The PCV mode by itself or with SIMV is not it would not be advisable to reduce the ventilatory rate
used for weaning. The PCV mode with or without from 8 breaths/minute to 2 breaths/minute in one ad-
SIMV is sometimes used for mechanically ventilating justment. Some authors suggest that 4 breaths/minute is
patients who have ARDS. This mode is also used with the lower limit for SIMV or IMV mode, unless PSV is
inverse-ratio ventilation and is then known as pressure- added to the system.
control inverse ratio ventilation (PCIRV). (1:860–862), (10:197–198).
Using SIMV with PSV provides the patient with the
necessary degree of backup (mandatory) ventilation IIIE2d
from the SIMV mode and offers the patient the oppor- 164. A. The arterial blood gases reveal an acute respiratory
tunity to establish her own rate, inspiratory flow, and acidosis, which indicates the need for an increased
inspiratory time via PSV. Gradually, the mandatory minute ventilation. The minute ventilation can be
rate used with the SIMV mode can be reduced, thereby increased by either increasing the tidal volume or

Chapter 5: Therapeutic Procedures 367

 increasing the ventilatory rate. Regarding the patient maintain the FRC without causing cardiovascular em-
presented here, her body weight is 135 lbs, which can barrassment.
be converted to kilograms as follows:
Ventilator management of acute pulmonary edema
135 lbs generally includes high FIO2s (greater than 0.60), high
=  61 kg delivery pressures, and moderate to high PEEP levels.
2.2 lbs/kg
IMV is usually not considered, because that mode of
Her tidal volume is 900 ml. The following calculation ventilation is associated with lower mean intrathoracic
demonstrates how to obtain the number of milliliters pressures (as are IDV and SIMV). Sighs would not be
of tidal volume/kg of ideal body weight: necessary, because PEEP and larger tidal volumes
would accomplish virtually the same goal.
900 ml
 14.5 ml/kg (2:304), (15:392).
61 kg
This tidal volume is toward the higher limit of the tidal IIIE2d
volume range of 10 to 15 ml/kg of ideal body weight.
166. B. If the patient has been assisting before the PEEP
Therefore, the ventilatory rate of 10 breaths/minute was added, the sensitivity should be adjusted so that
needs to be considered. The following steps outline the machine cycles on at about +8 cm H2O, assuming
how to establish a new ventilatory rate: the patient continues to assist. If the original high-pres-
sure limit is reached or is closely approached, the set-
STEP 1: Use the following relationship:
ting should be increased somewhat. A difference of 10
(desired ventilatory rate)(desired PaCO2) = cm H2O between the peak inspiratory pressure and the
(known ventilatory rate)(known PaCO2) high-pressure limit is generally accepted. If the patient
was receiving sigh volumes before the PEEP was in-
STEP 2: Insert the values given, and solve for the de-
stituted, this mode should be discontinued—because
sired ventilatory rate.
the sigh volumes in addition to the PEEP can generate
desired ventilatory rate = dangerously high intrathoracic pressures, thereby risk-
(10 breaths/minute)(50 mm Hg) ing barotrauma and cardiovascular compromise. Also,
the sigh mode’s function of preventing atelectasis has
40 mm Hg
now been taken over by the PEEP.
= 12 breaths/minute
(1:880), (2:535–549), (10:282).
A rate of 15 breaths/minute would result in hyperven-
tilation. While increasing the tidal volume will also IIIE2d
improve alveolar ventilation, a tidal volume of 1,200
ml would exceed the normal limits for this patient and 167. A. To improve oxygenation and the distribution of gas
could adversely increase the peak inspiratory pres- in the lung, the maneuver that is referred to as inflation
sure—thereby risking barotrauma. hold, or inspiratory pause, is sometimes used. Inflation
hold is accomplished by a ventilator adjustment,
(1:858–860), (2:527), (10:195–196), (17:35–38). which holds the air in the lungs at the end of inspira-
tion for a brief period. This maneuver increases the in-
IIIE2d spiratory time and the mean airway pressure (P̄aw). The
165. A. A routine, uneventful coronary bypass surgery lower the mean airway pressure, the less marked the
patient would be expected to be extubated after ap- cardiovascular effects.
proximately 24 hours of mechanical ventilation. An Although airway pressure is not quantitatively the same
FIO2 near 0.40 is usually sufficient. High inspiratory as pleural pressure, the mean values of both are linearly
pressures and PEEP are not usually needed or recom- related; thus, they can be used interchangeably to mon-
mended, for fear of potential cardiovascular compro- itor qualitative changes on the cardiovascular status.
mise. SIMV/IMV might be tolerated. Because high The longer the inspiration, the less time available for
inspiratory pressures and PEEP generally are not used expiration and the return of the intrapleural pressure to-
here, the sigh mode might be useful for the prevention ward normal. Conversely, when the duration of expira-
of microatelectasis. Some clinicians believe that low tion is prolonged, more time becomes available for the
levels of PEEP (3 to 5 cm H2O) might benefit the post- intrapleural pressure to return toward normal. Thus, for
thoracotomy patient by preventing post-surgical at- a constant rate of breathing, longer expiratory times are
electasis, however. These patients are prone to shallow associated with a lesser cardiovascular effect.
breathing because of incisional pain and lower chest-
wall compliance. Low levels of PEEP might help (1:845, 879), (10:85), (16:686–687).

368 Chapter 5: Therapeutic Procedures

IIIE2d value that is normal for them, rather than at the stan-
168. A. Time-cycled, pressure-limited ventilators refer to dard, normal values. SIMV and IMV modes are rec-
those ventilators that terminate inspiration after a pre- ommended to prevent respiratory alkalosis in COPD
set time elapses and limit the pressure generated dur- patients. Continuing with the present settings will re-
ing the inspiratory cycle. sult in a reduction of retained bicarbonate, which will
ultimately cause difficulties in weaning the patient
These types of ventilators provide control of the ventilato- from the ventilator.
ry rate directly or via manipulation of separate inspiratory
and expiratory time controls. For the latter variety, the (2:524), (10:233), (16:1033, 1124–1125).
ventilatory rate is a function of the inspiratory time and ex-
piratory time settings. For example, increasing the inspi- IIIE2d
ratory time while maintaining a constant expiratory time 171. C. The sensitivity control will determine the starting
will decrease the ventilatory rate and increase the I:E ratio. effort needed by the patient to initiate a breath. The
On the other hand, decreasing the inspiratory time while sensitivity is normally set so that a negative effort of 1
keeping the expiratory time constant increases the ventila- to 3 cm H2O will trigger the machine into inspiration
tory rate and decreases the I:E ratio. with minimal WOB. This situation enables the patient
to begin a breath with less effort. The negative pressure
(1:843–844, 845), (10:79–80, 84).
(–10 cm H2O) generated by the patient in this question
shows that the effort is more than adequate and that the
IIIE2d system has no obvious leaks. Increasing the sensitivity
169. A. The normal range for an initial tidal volume for setting will make the breathing effort less for the pa-
adults is 10 to 15 ml/kg of ideal body weight. Ideal tient. The patient will be able to cycle the IPPB ma-
body weight (IBW) can be estimated by using the fol- chine to inspiration more easily.
lowing formulas:
(1:781), (16:533).
males: IBW (lb) = 106 + 6(height inches  60)
females: IBW (lb) = 105 + 5(height inches  60) IIIE2d
172. D. Continuous or intermittent delivery of CPAP to
For this patient, the IBW would be 106 + 6(72 inches
non-intubated patients has been used successfully for
 60) or 178 lbs (81 kg). The appropriate range would
short periods of time under a fairly strict set of guide-
be 800 to 1200 ml for the initial tidal volume.
lines. When properly applied, CPAP is a means of
In the case presented here, the tidal volume is only 700 avoiding the use of artificial airways while resolution
ml, which is below the lower limit of the recom- of the primary problem is accomplished (for example,
mended range of 10 to 15 ml/kg (IBW). The arterial treatment of severe hypoxemia in patients who have
blood gases reveal an uncompensated respiratory aci- diffuse lung disease, such as P. carinii pneumonia).
dosis, indicating that this patient’s minute ventilation CPAP has also become a standard therapy in the treat-
is low. The respiratory acidosis here can be corrected ment of obstructive sleep apnea when delivered via a
by either increasing the tidal volume or the ventilatory nasal mask. One important criteria for the application
rate. Because the patient’s mechanically set tidal vol- of this therapy is that the patient must be able to venti-
ume is low, increasing this patient’s tidal volume to late adequately. Whenever acute respiratory failure is
900 ml would be reasonable. demonstrated by hypercapnia and acidosis, mechani-
cal ventilation is indicated. CPAP improves oxygena-
Some clinicians recommend that COPD and status
tion and treats atelectasis by increasing the FRC
asthmaticus patients who require mechanical ventila-
through recruitment and distention of alveoli, but it
tion should receive a tidal volume in the range of 8 to
cannot ventilate a patient who is unable to do so spon-
12 ml/kg (IBW). Because this patient is 30 years old
taneously.
and because no mention was made of his asthma, this
lower tidal-volume range can be ignored. (2:451), (15:733).
In addition, when we look at the blood gases, we see an
acute respiratory acidosis—which confirms the need to IIIE2d
increase minute ventilation. 173. B. Microprocessor ventilators enable the selection of
four different inspiratory waveforms: the sine wave,
(1:829, 896–998), (2:515, 524), (10:232–235). square wave, decelerating wave, and accelerating
wave. Little data support the benefits of one flow pat-
IIIE2d tern over another, however. Some studies show that the
170. A. Patients who have chronic hypercapnia should be tapering of flow at the end of inspiration with the sine
allowed to maintain their carbon-dioxide levels at the wave and decelerating waveforms might improve dis-

Chapter 5: Therapeutic Procedures 369

 tribution of gas in the lungs, decrease dead space, and ventilation mode should help reduce the risk of post-
improve oxygenation. These benefits are especially operative atelectasis.
true in situations where abnormalities of distribution
(1:860–861), (10:198), (16:616–617).
of ventilation exist. Any manipulation of inspiratory
waveforms must be closely monitored for possible ef-
fects on the I:E ratio, peak inspiratory pressure, and IIIE2d
mean airway pressure. 177. B. Discontinuation of CPAP on an infant is considered
in light of the FIO2. Once the FIO2 is below 0.40, the
(10:239–240, 279), (15:967), (16:1101–1102). CPAP level can be decreased in increments of 2 to 3
cm H2O. In the case presented here, the infant is being
IIIE2d sufficiently oxygenated (PaO2 75 torr) on an FIO2 of
174. D. The arterial blood-gas interpretation is uncompen- 0.30. Assessment of this infant indicates that lowering
sated respiratory alkalemia with mild hypoxemia. The the CPAP is appropriate at this time. A CPAP of 8 cm
patient is being hyperventilated. The goal here is to de- H2O has more potential risks than the FIO2 of 0.30.
crease the minute ventilation without increasing the Generally, weaning of PEEP and CPAP in infants oc-
dead space-tidal volume ratio. By decreasing the venti- curs judiciously at 2 to 3 cm H2O per change.
latory rate, the minute ventilation is reduced (increasing (1:980), (10:284–285).
PaCO2) without losing the recruitment of alveoli and
risking atelectasis. Initiating PEEP and increasing the IIIE2d
FIO2 are actions directed toward changes in the oxy-
genation status, rather than the patient’s ventilation. Al- 178. B. The patient is hypoventilating; therefore, the minute
though this patient does not show the classic symptoms ventilation must be increased. The tidal volume is ad-
of refractory hypoxemia, some CRTs might recommend equate for this patient, because she is receiving a tidal
PEEP if oxygenation does not improve quickly. volume at the upper end of the 10 to 15 cc/kg range.
For example,
(1:909–911), (10:251–252).
950 cc
= 14.7 cc/kg
IIIE2d 65 kg
175. C. CPAP pressure should not fluctuate more than 2 to Changing to the assist/control mode will not change the
3 cm H2O during inspiration, and the reservoir bag minute ventilation, unless the ventilatory rate is in-
must remain inflated throughout inspiration. The pa- creased because the patient has no spontaneous venti-
tient’s peak inspiratory flow rate can be estimated ac- lations. The hypoxemia should improve with correction
cording to the following equation: of the hypoventilation. Increasing the FIO2 to 0.70 or
VT increasing the PEEP to 8 cm H2O are efforts made to
= V̇ I improve oxygenation. Neither change does anything to
TI improve the patient’s ventilatory status.
where, (1:896–897), (10:206–207, 213, 251).
VT = tidal volume (ml)
TI = inspiratory time (seconds) IIIE2d
V̇ I = peak inspiratory flow rate (ml/second) 179. A. A hallmark sign of ARDS is a decreased pulmonary
compliance, which causes high ventilating pressures
The V̇I can then be multiplied by the factor 60 sec-
(peak inspiratory pressure). Increased airway resis-
onds/minute to convert the peak inspiratory flow rate
tance contributes to the generation of high peak inspi-
from ml/second to ml/minute.
ratory pressures. In this case, however, any broncho-
(1:865–866), (10:281–282). spasm and airway secretions that might be responsible
for the development of high inspiratory pressures are
IIIE2d being addressed via the administration of sympath-
omimetic drugs (bronchodilators) and by the applica-
176. A. The patient’s arterial blood gas and acid-base data
tion of tracheobronchial suctioning. Although ARDS
indicate mild hyperventilation (uncompensated respi-
is not considered to be associated with bronchocon-
ratory alkalosis). Instituting SIMV will enable the pa-
striction, some clinical evidence exists—indicating
tient to establish her own baseline level of ventilation.
that there might be a reversible component to the air-
This patient appears to have an excellent ventilatory
flow limitation.
drive and might be able to maintain an adequate minute
ventilation on an SIMV rate of 12 breaths/minute. Ad- Worsening of the ARDS—specifically, a further de-
ditionally, the mandatory breaths associated with this creasing lung compliance (reflected by static compli-

370 Chapter 5: Therapeutic Procedures

 ance measurements)—might be responsible for the IIIE2e
frequent sounding of the high-pressure alarm. Greater 182. B. After exhausting an array of mechanical attempts to
decreases in lung compliance generally result more produce synchronous mechanical ventilation (to no
from pulmonary capillary permeability, increased fluid avail), the patient might benefit from sedation with
entering the alveoli, more widespread atelectasis, and benzodiazepine. Midazolam (Versed) can be adminis-
pulmonary fibrosis. At this point, the CRT must in- tered I.V. to try to achieve patient compatibility with
crease the high-pressure limit to accommodate the the ventilator.
higher peak inspiratory pressure.
The following list delineates various ventilator-setting
PCIRV, which often produces a decreased peak inspi- adjustments that can be attempted to alleviate the
ratory pressure, might ultimately become a considera- problem of patient-ventilator asynchrony:
tion.
1. Increase the sensitivity of the triggering mechanism
(1:518–519, 876), (2:512), (10:215–216, 239, 277, or use flow triggering.
286), (15:334).
2. Increase the peak flow rate to meet the patient’s in-
spiratory demands.
IIIE2d
180. C. Best PEEP, or optimal PEEP, is defined as the PEEP 3. Use a decelerating flow pattern.
that achieves the best oxygenation with the least car- 4. Attempt to set the mechanical respiratory rate to
diovascular side effects. In the optimal PEEP trial pre- match that of the patient.
sented here, the patient’s PaO2 and static compliance
improved with each increase in PEEP. The increase 5. Tidal volume adjustments might be helpful.
from 8 to 12 cm H2O, however, showed less improve- Once these measures produce no beneficial results, the
ment in the arterial PO2 and a decrease in the static problem might be patient anxiety, which can be phar-
compliance compared with the previous increases. A macologically addressed.
significant negative response also occurred with the
blood pressure. Therefore, the optimal PEEP for this (1:905, 915), (16:591, 626).
patient is 8 cm H2O.
IIIE2f
(1:515), (2:538–545), (10:270–275), (15:731–732).
183. D. There are numerous mechanical and physiological
measurements used to evaluate a patient’s readiness
IIIE2d for the weaning process. The mechanical measure-
181. B. Each of these factors will decrease the dynamic ments and their guideline values include the following:
compliance and consequently the amount of volume
• maximum inspiratory pressure (MIP):  -20 cm
that is delivered per unit of pressure change. Increased
H2O
airway secretions and parasympathetic stimulation of
• vital capacity (VC):  10 ml/kg
the tracheobronchial tree (bronchoconstriction) will
• spontaneous ventilatory rate (f): > 6 breaths/minute
increase the airway resistance. Fluid overload will
and < 25 breaths/minute
cause a decreased static compliance. Again, these cir-
• patient compliance on ventilator: > 30 ml/cm H2O
cumstances will result in less volume delivered by the
pressure-cycled ventilator. Physiologic measurements and their guideline values
are as follows:
Pressure-cycled ventilators will not have the capacity to
deliver a constant tidal volume, because the patient’s • VD/VT: < 0.55 to 0.60
lung characteristics (lung compliance and airway resis- • Q̇s/Q̇t: < 15%
tance) change. When airway resistance and lung com- • P(A-a)O2 (breathing 100% O2): < 300 to 350 torr
pliance remain constant, the tidal volume delivered by
Based on the mechanical factors measured and the val-
a pressure-cycled ventilator will be virtually the same.
ues obtained for the patient described, he appears to be
Decreasing the inspiratory flow rate will lengthen the a suitable candidate for weaning from mechanical ven-
inspiratory time but will not significantly change the tilation. Appropriate physiologic data should, likewise,
tidal volume being delivered to normal lungs. The like- be gathered to help make a more sound decision.
lihood of fluctuating tidal volumes is a major limita- Again, the values shown here are only guidelines.
tion in the use of pressure-cycled ventilators for
(1:971, 975), (10:325–326), (15:1019–1033),
continuous mechanical ventilation.
(16:629, 631).
(1:894–911), (10:237–239), (15:642–644).

Chapter 5: Therapeutic Procedures 371

IIIE2f IIIE2f
184. D. The patient has not tolerated the T-piece weaning 186. B. To date, no single measurement has had the capa-
trial. The minute ventilation (V̇E) is basically the same bility to successfully predict a patient’s readiness to
for these two sets of data. be weaned from mechanical ventilation. The most im-
portant criterion, however, is whether or not the un-
9 A.M. Data 9:45 A.M. Data derlying disease process or condition that caused the
Spontaneous V̇ E patient to be mechanically ventilated has improved.
IMV V̇ E with T-Piece Once clinical improvement has been seen, the evalua-
tion of more specific data is necessary. Numerous po-
V̇E = f  VT V̇E = f  VT tentially useful psychological and cardiopulmonary
= (5 breaths/min) (500 cc) = (26 breaths/min) (350 cc) factors have been useful in predicting the weaning
= 2,500 cc/minute or = 9,100 cc/minute or
process. The CRT must be aware of all of these fac-
2.5 liters/minute 9.1 liters/minute
tors, especially the cardiopulmonary physiological
data. The CRT must also be familiar with the gener-
Spontaneous V̇ E ally accepted values thought to be predictive of suc-
cessful weaning. Equally important is the realization
V̇E = (14 breaths/min) that a combination of measurements, not any one by
(500 cc) itself, enhances the prediction of success. In this case,
= 7,000 cc/minute or an MIP measurement more negative than –20 cm H2O
7.0 liters/minute
within 20 seconds correlates well with a vital capacity
greater than 15 ml/kg and suggests that the patient is
TOTAL V̇ E likely able to cough, breathe deeply on command, and
maintain spontaneous ventilations. A normal MIP is
V̇E: = 2.5 liters/min the ability to generate at least a pressure of –80 cm
 7.0 liters/min H2O in 10 seconds.
= 9.5 liters/minute
(1:971, 975, 983–985), (2:528–530), (10:325–329).

The dead-space ventilation and the WOB, however,

have increased significantly since the patient was IIIE2f
placed on the T-piece. While a PaO2 is not given in this 187. B. The fundamental guiding principle regarding wean-
situation, the increased heart rate is suggestive of in- ing a patient from mechanical ventilation is that wean-
creasing hypoxemia. ing should occur when the clinical problem for
initiating mechanical ventilation has been corrected.
(1:974–986), (10:325, 329–331), (15:1020–1024).
Assessment of this reversal is determined by obtaining
certain physiologic measurements (e.g., respiratory
IIIE2f
rate, MIP, VC, V̇E, and ABGs). These weaning criteria
185. B. Conventional weaning is normally accomplished generally indicate the degree of readiness of a patient
with a Briggs adaptor or T-piece trials for five to 10 min- to assume spontaneous ventilation.
utes. This method is most commonly used when patients
have been mechanically ventilated for short periods Once it has been determined that the patient has ade-
(fewer than two days). These patients have usually been quate ventilatory-muscle strength, the drive to breathe,
receiving mechanical ventilation following thoracic or a reasonable WOB level, and adequate oxygenation,
cardiac surgery or an uncomplicated drug overdose. The weaning attempts tend to be successful.
presence of tachypnea and dysrhythmia are definite (1:970–977), (10:325–328).
signs that the patient is not tolerating the weaning pro-
cedure. SIMV is an alternative weaning method that per-
mits a more gradual transition from full ventilatory IIIE2g
support. SIMV might be better tolerated by patients who 188. A. Bronchiectasis is a condition in which the bronchi
have been mechanically ventilated for long periods. are abnormally and permanently dilated. This condi-
CPAP, or a spontaneous mode, is also available on some tion is generally caused by frequent lung infections
ventilators; however, unless it is combined with and long-standing airway obstructions. Bronchiectatic
pressure-support ventilation, it would not be appropriate patients produce copious amounts of foul-smelling
for patients who are not tolerating the T-piece trial. The (fetid) sputum that upon standing, often separates into
CPAP mode is often associated with an increased WOB. three distinct layers. Because bronchial hygiene is of
(1:976–977), (10:331–332), (16:631–632). primary importance in this condition, bronchopul-

372 Chapter 5: Therapeutic Procedures

 monary drainage to the affected segments is a corner- Beta-two agonists can cause the following adverse ef-
stone of therapy for bronchiectasis. The addition of fects:
percussion or vibration might further increase sputum
— tachycardia
production. These techniques, along with aerosolized
— tremors
bronchodilators and coughing techniques, substan-
—dizziness
tially increase sputum production and lung clearance
—decreased PaO2 via V̇/Q̇ mismatching
of abnormal secretions in these patients.
—nausea
(1:459), (2:288), (16:516). —hypokalemia
So, if a patient who is receiving a nebulized -two ag-
IIIE2g onist becomes tachycardic and displays tremors, the
189. D. A slow and deep breathing pattern with an end- dosage of the medication can be reduced. This action
inspiratory hold enables the best particle penetration and is taken to alleviate the adverse effects. In the case of
deposition than any other breathing pattern. The amount metaproterenol, the range of recommended dosage is
of oxygen and medication delivered to the patient via a 0.2 ml to 0.3 ml. Therefore, decreasing the dose in this
small-volume nebulizer is dependent on the patient’s situation to 0.2 ml is appropriate.
breathing pattern. The amount of oxygen and medication
is inversely related to the patient’s ventilatory rate and (1:574–577), (16:482–483).
tidal volume; i.e., the minute ventilation (V̇E).
IIIE2j
(1:696), (16:438–442).
193. B. A Heimlich valve (refer to Figure 5-11) can be used
to drain the intrapleural space of air.
IIIE2h
190. A. High-volume delivery of a bland aerosol via ultra-
sonic or hydrosphere nebulizers can be indicated to From
Patient's
promote the clearance of thick secretions, especially Intrapleural
when used in conjunction with other procedures, such Space
as postural drainage and coughing techniques. Treat-
ments of 30 to 60 minutes four times a day are just as
effective as continuous therapy and are more likely to
be tolerated by the patient. The CRT must explain the
purpose of the treatment to the patient.
(1:698, 701), (16:463).
Figure 5-11: Heimlich valve connected to a patient’s inter-
IIIE2i pleural space.
191. D. The normal adult dosage of Proventil is 0.5 ml or
2.5 mg. The drug is supplied in a 0.5% solution for in- If the pneumothorax is complicated with a pleural ef-
halation or in equivalent unit doses. Proventil is con- fusion, however, a thoracostomy (chest) tube must be
sidered a moderately long-acting drug that is routinely inserted to drain the pleural effusion. A thoracostomy
given every four to six hours. Because the patient is re- provides for more thorough and complete removal of a
sponding to the treatment, the best approach is to rec- pleural effusion. A pleural effusion must be drained
ommend increasing the dose to the standard adult expediently. Undrained fluid can form loculations
dosage. The choice of a delivery device, such as a quickly within the pleural space, complicating the pa-
hand-held nebulizer or an MDI, is made based on the tient’s condition. Aspirating a pleural effusion with a
patient’s ability to effectively inhale the drug and his needle might be incomplete, leading to complications.
ability to master the proper technique for using the in- A Heimlich valve is intended to drain intrapleural air,
haler. The question does not provide enough informa- not a pleural effusion. A thoracostomy tube must be
tion to make a decision about this choice. used to drain the pleural effusion.

(1:453, 455), (2:582–584), (8:387–388), (15:814). A thoracentesis should not be confused with drainage
of a pleural effusion. A thoracentesis is the aspiration
IIIE2i of pleural fluid from the intrapleural space for the pur-
pose of diagnostic sampling.
192. C. As a group, beta-two agonists tend to produce sim-
ilar adverse effects. Some adrenergic bronchodilators The pneumothorax must continuously be drained to
cause a greater magnitude of adverse effects compared enable the lung tissue to heal. Generally, when no air
to other drugs in the same category. moves through the drainage system for 48 hours, the

Chapter 5: Therapeutic Procedures 373

 chest tubes are usually removed and the lungs are be- IIIE3
lieved to be healed. 196. B. Placing the patient in a semi-Fowler position will do
(1:482–484), (9:231–232), (15:1089–1092). little to make the endotracheal intubation procedure
more tolerable for the patient. In fact, this position
IIIE3 would create difficulty aligning the oral cavity, orophar-
ynx, and trachea for easy tube insertion. Administering
194. A. Clinical experience has demonstrated that patients
100% oxygen would not have a calming effect. The pa-
who have COPD tend to respond more favorably to an
tient might relax somewhat during the bagging of 100%
anticholinergic bronchodilator (ipratropium bromide)
oxygen, but once the procedure began, the patient’s anx-
than they do to a beta-two agonist. Therefore, the anti-
iety and fear would likely reappear.
cholinergic bronchodilator, ipratropium bromide (Atro-
vent), should be recommended before any adrenergic To facilitate the procedure and to make it tolerable, se-
bronchodilator such as metaproterenol, albuterol dation of the patient is warranted. The administration of
(Proventil or Ventolin), or bitolterol (Tornalate). A num- a benzodiazepine such as Valium or Versed, in conjunc-
ber of COPD patients respond favorably to the MDI tion with a narcotic agent such as fentanyl (Sublimaze),
Combivent, which contains both Atrovent and Ventolin. is indicated. Benzodiazepines produce sleepiness and
anterograde amnesia and cause minimal respiratory de-
(1:577), (16:491).
pression and a little fall in blood pressure. The narcotic
induces analgesia (pain reduction) and cough suppres-
IIIE3
sion.
195. A. Patients who are asynchronous with a mechanical The patient should be sedated enough to be in a state
ventilator are usually either inspiring when the venti- of sleep, but still responsive to verbal input. If the pa-
lator cycles off or exhaling when the ventilator cycles tient does not respond to verbal stimuli, oversedation
on. The clinical colloquialism for this condition is has possibly occurred. Then, the intubation procedure
“fighting” or “bucking” the ventilator. This condition becomes an emergency, because airway obstruction
frequently occurs when patients are mechanically ven- can rapidly follow.
tilated in either the control or assist/control mode.
Neuromuscular blocking agents will not cause seda-
Whenever this situation arises, the clinician must eval- tion, but they will induce paralysis. They would be in-
uate the patient to determine the cause of the asyn- appropriate in this situation, because they would cause
chronous breathing. Possible causes include (1) right significant respiratory depression and create an emer-
mainstem bronchus intubation, (2) excessive secre- gency situation.
tions, (3) pneumothorax, (4) inadedquate ventilator
setup, (5) pain, and (6) anxiety. (10:298–299), (16:591–592).

If the inspiratory flow rate and/or sensitivity are both IIIE3

set appropriately, the problem is likely patient fear and
anxiety. The patient might also require paralytics. 197. D. The purpose of airborne precautions is to protect
the health-care provider from conditions or illnesses,
Benzodiazepines—i.e., Versed (midazolam) or Valium such as tuberculosis, measles (Rubella), and varicella.
(diazepam)—are anxiolytics. Benzodiazepines are Respiratory protection must be adhered to; i.e., gloves,
anxiolytics that produce sedation and hypnosis. In a gown, and a mask must be worn.
other words, they reduce anxiety (produce a calming
effect and induce drowsiness and the onset of a state of Droplet precautions and contact precautions also de-
sleep). Paralytics (either nondepolarizing agents or de- mand respiratory protection. Likewise, standard pre-
polarizing drugs) are given to cause skeletal-muscle cautions require the wearing of gloves, a gown, and a
relaxation. Drugs such as pancuronium bromide (non- mask. Standard precautions apply to all patients re-
depolarizing) or succinyl choline (depolarizing) are gardless of diagnosis.
also commonly used. (Centers for Disease Control and Prevention).
Paralytics do not relieve pain or anxiety. Sedatives
eliminate anxiety, and analgesics (morphine) reduce IIIE3
pain. Hence, drugs from these categories are com- 198. D. Ipratropium bromide is classified as an anticholin-
monly given in combination. ergic bronchodilator or a parasympatholytic. Clinical
experience with ipratropium bromide has shown it to
These medications enable patients needing controlled
be generally more effective as a bronchodilator than
or assist-controlled mechanical ventilation to interface
beta 2 agonists for patients who have COPD. Using
favorably with the mechanical ventilator.
ipratropium bromide for the day-to-day treatment of
(1:858), (10:195–196, 298–300), (16:626). asthma produces inconsistent results.

374 Chapter 5: Therapeutic Procedures

 Ipratropium bromide, also known by the trade name ity. Isoproterenol is not beta-two specific. Therefore, it
Atrovent, bronchodilates the airways by blocking causes the greatest degree of tachycardia (a beta-one
vagal-reflex bronchospasm and by decreasing intrinsic response) than any of the other bronchodilators listed.
vagal tone.
(1:574–577), (2:582), (8:105–122), (15:180).
The presence of expiratory wheezing in this COPD pa-
tient is a significant sign, because clinical studies have IIIE3
shown that COPD patients who are wheezing tend to 202. D. Sympathomimetics are medications that mimic the
respond more favorably to bronchodilator therapy than activity of the sympathetic nervous system. Numerous
COPD patients who do not exhibit wheezing. Further- sympathetic nervous-system receptors exist through-
more, polyphonic wheezing indicates that multiple air- out the body that when stimulated, produce a variety of
ways are involved. Keep in mind that wheezes effects.
(high-pitched, continuous sounds) result from the
rapid flow of air through partially obstructed airways. Four distinct groups of sympathetic receptors have
This partial obstruction can be caused by either bron- been identified: (1) alpha-1, (2) alpha-2, (3) beta-1,
chospasm, mucosal edema, airway inflammation, tu- and (4) beta-2. Alpha-1 receptor stimulation generally
mors, or foreign bodies. produces vasoconstriction, blood-pressure elevation,
and heart-rate deceleration. Alpha-2 receptor simtula-
(1:312–314, 456), (8:128–133), (9:65–66). tion is known to cause different responses, depending
on where the alpha-2 receptor is located. Alpha-2 pre-
IIIE3 synaptic receptors at the neuroeffector junction of the
199. A. Among the side effects and hazards of n-acetylcys- peripheral sympathetic nervous system act as a nega-
teine (Mucomyst) is bronchospasm. Therefore, the tive feedback mechanism to limit the amount of nor-
general recommendation is that Mucomyst be concur- epinephrine released. Some of the neurotransmitter
rently nebulized with a bronchodilator. In fact, the (norepinephrine) released migrates back to the pre-
drug manufacturer (Mead Johnson) has a commer- synaptic membrane and stimulates alpha-2 receptors
cially available preparation of 10% Mucomyst and iso- there to terminate further release of norepinephrine.
proterenol for this explicit reason. The dose is 10% Alpha-2 receptors in the central nervous system are lo-
Mucomyst with 0.05% isoproterenol; 3 cc to 5 cc, cated on the smooth muscle of the arterioles. Antihy-
QID. pertensive medications such as clonidine and
This volume of medication is suitably accommodated methyldopa act on these alpha-2 receptors and effec-
in a small-volume nebulizer. Mucomyst is compatible tively decrease the blood pressure.
with other commercially available bronchodilators. Al- Beta-1 agonists stimulate the heart, causing an in-
ternatively, the bronchodilator can be given first, fol- creased heart rate (positive chronotropism) and an in-
lowed by the nebulization of Mucomyst. creased myocardial contractility (positive inotropism).
(1:579–580), (2:578–579), (8:165–167). Beta-2 agonists stimulate receptors on the surface of
bronchial smooth muscles, causing bronchodilatation.
IIIE3 The medication that would cause relief of nasal con-
200. D. One of the side effects of Mucomyst is bron- gestion is an alpha-1 agonist (e.g., phenylephrine).
chospasm. Therefore, a medication that predominantly
(1:574–577), (2:580), (8:105–122).
stimulates beta-two receptors should be concomitantly
administered, to produce bronchodilatation. Albuterol
(metaproterenol sulfate) is a beta-two agonist; there- IIIE3
fore, it can be nebulized together with Mucomyst. 203. D. Hypertonic saline solutions are commonly used to
induce sputum, and the ultrasonic nebulizer is an ap-
The manufacturer of Mucomyst, Mead Johnson, rec- propriate choice for delivering the solution to the air-
ognizes this potential side effect and offers a pre- way. Patients who have hypersensitive airways have a
mixed combination of 10% Mucomyst with 0.05% tendency to develop increased airway resistance when
isoproterenol hydrochloride. aerosols are inspired, particularly irritating substances.
(1:579–580), (2:578), (8:165–167). Pretreatment or simultaneous treatment with a rapid-
acting, sympathomimetic bronchodilator is the recom-
IIIE3 mended approach to resolving this problem. The
problem also illustrates the importance of staying at
201. D. All of the drugs listed are beta-adrenergic bron-
the bedside of patients who are receiving high-volume
chodilators (beta agonists). Albuterol, terbutaline,
aerosol therapy.
metaproterenol, and isoetharine have different degrees
of beta-two specificity. They have low beta-one activ- (1:581), (8:172).

Chapter 5: Therapeutic Procedures 375

IIIF1 marrow to enter venous circulation. If the esophageal
204. A. Basic life support (BLS) standards indicate that af- or gastric wall ruptures, air can enter the peritoneal
ter unresponsiveness has been verified, the rescuer cavity (pneumoperitoneum). This condition elevates
must call for help and activate the Emergency Medical abdominal pressure, creating further resistance to ven-
System (EMS). Once that step has been performed, the tilation. Too much pressure exerted on the sternum and
CRT must determine breathlessness. the application of chest compressions for too long a
period might cause cardiac contusions.
(1:630–632), (15:1118), (16:817–818).
(1:640), (16:822).
IIIF1
IIIF1
205. B. Beginning with shallow depressions of the sternum
and gradually increasing the depth of compressions 209. A. Based on the circumstances, a pneumothorax is a
enables the sternum and rib cage to become slightly possible complication here. A pneumothorax is a pos-
more mobile and elastic. This approach can reduce the sible early complication of a tracheostomy in and of it-
incidence of complications associated with closed- self. The incidence of this complication becomes
chest compression (e.g., rib fractures and soft-tissue greater when positive pressure is applied to a recent
injuries). The sternum should eventually be depressed tracheostomy.
1 1/2 to 2 inches for effective compression. (16:599).
(1:636), (15:1118), (16:821–822).
IIIF1
IIIF1 210. D. If a victim is found unconscious and the cause is not
206. D. Unsuccessful ventilation indicates an occluded air- known, the CRT should (1) establish unresponsive-
way. The Heimlich maneuver should be performed. ness, (2) call for help, (3) establish the airway, (4) es-
The Heimlich maneuver requires the rescuer to place tablish breathlessness, and (5) begin ventilation.
both hands against the victim’s epigastrium and apply (The Journal of the American Medical Association,
compression to that area for the purpose of elevating Guidelines for Cardiopulmonary Resuscitation and
the intrathoracic pressure. The elevated intrathoracic Emergency Cardiac Care, October 1992, Vol. 268, No.
pressure will hopefully dislodge whatever might be 16, p. 2187), (1:630–632), (16:818–820).
occluding the airway. The abdominal thrusts, if unsuc-
cessful, are followed by the finger sweep for the pur-
IIIF1
pose of clearing the airway.
211. B. This person is experiencing a respiratory arrest be-
(1:643–644), (15:1118), (16:823). cause she is apneic and has a palpable carotid pulse.
Therefore, the most appropriate action for the CRT to
IIIF1 take is to continue ventilating the victim at the
207. D. The patient described here has a spinal cord injury. prescribed adult ventilatory rate (10 to 12
Such a patient should not have his head and neck hy- breaths/minute), unless the patient resumes adequate
perextended, because this maneuver can further injure spontaneous ventilations. Cardiac compressions are
the patient. Instead, the rescuer should use the jaw- inappropriate in this case, because cardiac activity ex-
thrust method to establish an airway. ists (as indicated by the palpable carotid pulse).
The maneuver is performed by grasping with both (The Journal of the American Medical Association,
hands the victim’s lower jaw and lifting it. In the Guidelines for Cardiopulmonary Resuscitation and
process, the victim’s mandible displaces forward. Emergency Cardiac Care, October 1992, Vol. 268, No.
16, p. 2187), (1:630–632), (16:820).
(1:640), (16:918–820).
IIIF2
IIIF1
212. D. Defibrillation is the application of an asynchronized
208. D. Perhaps the greatest number of complications re-
electrical shock to the myocardium, attempting to
sults from external cardiac compression. Failure to lo-
achieve simultaneous myocardial depolarization. De-
cate the proper compression site or applying pressure
fibrillation is applied to patients who exhibit ventricu-
with the fingers and palm of the hand can produce rib
lar fibrillation and pulseless ventricular tachycardia.
fractures. The broken ends of the fractured ribs can
penetrate lung tissue or lacerate the liver. The com- Although similar to defibrillation, cardioversion in-
pressions of the rib cage might result in small fractures volves the application of an electrical shock to a pa-
of the ribs and sternum, allowing fat from the bone tient’s myocardium in synchrony with the R wave on

376 Chapter 5: Therapeutic Procedures

 an ECG tracing. The purpose of applying the electrical IIIF2
shock in synchrony with the R wave is to avoid having 215. A. Defibrillation is the application of an asynchronized
the myocardium stimulated during the heart’s refrac- electrical shock to the myocardium. The purpose of
tory period, thus avoiding ventricular fibrillation or defibrillation is to achieve simultaneous myocardial
pulseless ventricular tachycardia. Furthermore, car- depolarization. Defibrillation is indicated for ventricu-
dioversion requires less electrical energy than defibril- lar fibrillation when the hemodynamically unstable pa-
lation. Cardioversion is applied to patients who have tient has polymorphic ventricular tachycardia or
the following dysrhythmias: pulseless ventricular tachycardia.
Dysrhythmias Treated with Cardioversion: Defibrillation is contraindicated for pulseless electrical
• supraventricular tachycardia activity (PEA), as in pulseless ventricular tachycardia
• atrial flutter and asystole, because the electric current produces a
• atrial fibrillation parasympathetic discharge. Defibrillation can elimi-
• ventricular tachycardia nate any possibility for the return of spontaneous my-
ocardial activity.
(1:653, 657), (American Heart Association, Advanced
Cardiac Life Support, 1994, pp. 1-35, 4-1, 4-6, and 4-7). (American Heart Association, Advanced Cardiac Life
Support, 1994, pp. 1-7 and 4-7).
IIIF2
IIIF2
213. B. When tachycardia produces serious cardiovascular
signs and symptoms in a hemodynamically unstable 216. D. Vagal maneuvers increase parasympathetic tone
patient, cardioversion should be used before antidys- and slow atrioventricular (AV) node conduction time.
rhythmic medications are administered. Furthermore, They are used to treat paroxysmal supraventricular
in these situations, a heart rate greater than 150 tachycardia. Patients experiencing this dysrhythmia re-
beats/min. warrants immediate cardioversion. currently frequently self-administer some of these va-
gal maneuvers, which include the following:
Immediate cardioversion is usually unnecessary for
heart rates less than 150 beats/minute. Vagal Maneuvers for Treating Paroxysmal Supra-
ventricular Tachycardia:
(American Heart Association, Advanced Cardiac Life
Support, 1994, pp. 1-32 to 1-35, and 4-3). • carotid sinus massage
• facial immersion in ice water
• breath-holding
IIIF2
• coughing
214. C. When interventions such as defibrillation, epin- • squatting
ephrine, and lidocaine prove to be ineffective in the • circumferential digital sweep of the anus
treatment of ventricular fibrillation or ventricular • eyeball massage (can produce retinal detachment
tachycardia, bretylium tosylate is used. In such cases, and should never be performed)
bretylium is administered I.V. in a dose of 5 mg/kg by • Trendelenburg position
rapid injection. Thirty to 60 seconds later, defibrilla- • nasogastric tube placement
tion should be performed again. If this intervention is • gag reflex stimulation by tongue blades, fingers, or
unsuccessful, the dose of bretylium is doubled (10 oral ipecac
mg/kg) and is given five minutes later. Ultimately, • MAST garments
doses of 10 mg/kg can be given at 5- to 30-minute in-
tervals, up to a maximum dose of 35 mg/kg. Carotid sinus massage must be performed carefully
and while the patient has his ECG monitored. This
Verapamil, a calcium-channel blocker, reduces the procedure should be avoided for elderly patients. Pres-
myocardium’s oxygen consumption via its negative in- sure (massaging) to the carotid sinuses must be applied
otropic and negative chronotropic effects. Verapamil is for only five to 10 seconds. The patient’s right carotid
useful for treating paroxysmal supraventricular tachy- sinus is massaged with the patient’s head turned to-
cardia. This drug is given in a dose of 2.5–5.0 mg/kg ward the left. Sides can be alternated.
I.V. bolus over one to two minutes.
(American Heart Association, Advanced Cardiac Life
Diltiazem is administered as a bolus of 0.25 mg/kg I.V. Support, 1994, p. 1-37).
over two minutes for the treatment of paraoxysmal
supraventricular tachycardia. IIIF2
(American Heart Association, Advanced Cardiac Life 217. A. Calcium chloride makes calcium ions available,
Support, 1994, pp. 7-9 to 7-12). thus increasing the myocardium’s force of contractility

Chapter 5: Therapeutic Procedures 377

 (positive inotropism). At the same time, calcium ions IIIF4
can either increase or decrease systemic vascular re- 221. B. After the initial 15 to 30 seconds of ventilation dur-
sistance. Normally, calcium consistently elevates sys- ing resuscitation, the CRT needs to evaluate the in-
temic arterial blood pressure by its positive inotropic fant’s heart rate. This evaluation can be performed by:
action and its vasoconstricting effects.
1. listening to the apical heart beat with a stethoscope
Verapamil is a calcium-channel blocker that causes 2. palpating either the umbilical or brachial pulse
negative inotropic and negative chronotropic effects.
Adenosine is a purine nucleoside that produces a (Neonatal Resuscitation, American Heart Association,
slower conduction time through the atrioventricular page 3B-21, 1996).
(A-V) node.
IIIF4
Bretylium is an adrenergic neuronal blocking agent
that is used to increase the effectiveness of defibrilla- 222. C. Ordinarily, drying and suctioning a newborn provides
tion. Studies have not supported this expectation, how- sufficient tactile stimulation to cause an infant to breathe.
ever. Lidocaine is used more frequently for this Sometimes, however, these actions do not stimulate res-
purpose, because lidocaine has fewer potential adverse piration, and other forms of tactile stimulation are neces-
hemodynamic effects than bretylium. sary. Two other forms of tactile stimulation are as follows:

(American Heart Association, Advanced Cardiac Life 1. rubbing the infant’s back
Support, 1994, pp. 7-9, 7-11, and 7-13). 2. slapping the soles of the infant’s feet
At the same time, free-flow oxygen should be adminis-
IIIF2 tered while these other forms of tactile stimulation are
218. D. A pneumothorax causes the patient to feel dyspneic applied. The application of a cold compress to the in-
secondary to decreased lung volume and a lower arte- fant is inappropriate, because it can cause hypothermia.
rial PO2. Hypoxemia occurs as a result of ventilation- (Neonatal Resuscitation, American Heart Association,
perfusion abnormalities and intrapulmonary shunting. page 2-27, 1996).
Administering 100% oxygen would be useful from
two standpoints. First, the higher FIO2 might relieve or IIIG1b
lessen the degree of hypoxemia. Second, the higher
223. C. Figure 5-12 illustrates how a patient should be po-
alveolar PO2 might reduce the volume of the pneu-
sitioned for a thoracentesis.
mothorax via absorption. None of the other choices of-
fer measures that assist with this problem. Notice how the patient is seated along the side of the
bed, upright while leaning slightly forward.
(American Heart Association, Advanced Cardiac Life
Support, 1994, pp. 13-4 to 13-5), (1:483–485), (15:636–638), (18:1105).
(7:334).
IIIG1d
IIIF3 224. B. Cardioversion is the application of electrical energy to
219. A. The proper length of a laryngoscope blade can be the myocardium of a patient who has an organized dys-
determined by holding it next to the patient’s face to rhythmia resulting in a high ventricular rate and is showing
determine that it extends from the patient’s lips to the either the signs or symptoms of cardiac decompensation.
larynx (thyroid cartilage). Cardioversion is indicated for the following conditions:

(Pediatric Advanced Life Support Manual, American 1. atrial fibrillation

Heart Association, page 2-11, 1997). 2. atrial flutter
3. supraventricular tachycardia
4. ventricular tachycardia
IIIF3
220. C. According to the Pediatric Advanced Life Support During cardioversion, the electrical stimulus is applied
Manual published by the American Heart Association, to the heart in synchrony with the R wave. Cardiover-
pediatric manual resuscitation bags must deliver a sion also differs from defibrillation in the amount of
minimum tidal volume of 450 ml. Manual resuscita- electrical energy used. Less electrical energy is used
tors that have smaller tidal volumes might not provide with cardioversion than with defibrillation.
an adequate tidal volume for pediatric patients who The patient in this question is experiencing atrial fib-
have stiff (low-compliant) lungs. rillation, which indicates cardioversion.
(Pediatric Advanced Life Support Manual, American (1:657), (Advanced Cardiac Life Support, American
Heart Association, page 2-5, 1997). Heart Association, pp. 1-35 and 3-11 to 3-12).

378 Chapter 5: Therapeutic Procedures

IIIG1d • review of patient home-exercise logs
225. A. The patient described in this question appears to be • strength measurement
having a myocardial infarction. According to the ad- • flexibility and posture
vanced cardiac life-support standards established by • performance on specific training modalities
the American Heart Association, such patients must be • weight gain or loss
administered oxygen at 4 liters/min., chewable aspirin, • psychological test instruments
nitroglycerin (sublingual, spray, or paste) if the sys- • frequency of cough, sputum production, or wheez-
tolic blood pressure exceeds 90 torr, I.V. morphine, ing
thrombolytic agents, nitroglycerin I.V., beta-blockers, • dyspnea measurements
and heparin I.V. • changes in activities of daily living (ADL)
• post-program questionnaires
Adenosine I.V. is indicated as the initial drug of choice • frequency and duration of hospitalization
for patients who have hemodynamically stable parox- • frequency of emergency department visits
ysmal supraventricular tachycardia.
(1:1101), (16:883–884).
Bretylium is administered as the third agent for treat-
ing sustained ventricular tachycardia. IIIG2a
(Advanced Cardiac Life Support, American Heart Asso- 227. D. Before entering a pulmonary-rehabilitation program,
ciation, pp. 1-37, 1-39, 1-47 and 1-48), (16:862–863). a patient must be thoroughly evaluated (i.e., history,
physical exam, medical exam, and testing to confirm the
patient’s diagnosis). A comprehensive view of the patient
IIIG2a must be obtained, including determining problems with
226. D. Patient outcomes following a pulmonary-rehabili- other body systems (i.e., gastrointestinal, musculoskele-
tation program must be evaulated. Activities that can tal, or sinus). All patient symptoms must be reviewed,
serve as useful tools for evaluating patient outcomes and social, medical, occupational, and environmental
include the following: histories must be obtained.
• before and after a six- or 12-minute walk Exercise assessment is necessary for the following rea-
• before and after a pulmonary exercise stress test sons:

Pleural
fluid Muscle, fat,
Lung Rib skin
Visceral
pleural
Parietal
pleural

Figure 5-12: Patient position for thoracentesis. The patient assumes an upright position along
the side of the bed and leans over a bed table.

Chapter 5: Therapeutic Procedures 379

 • to ascertain the appropriate exercise program IIIG2a
• to determine whether hypoxemia develops with ex- 230. C. For successful abstinence from cigarette smoking,
ercise the following components must be addressed in a
• to find out whether oxygen therapy is required dur- smoking-cessation program:
ing exercise
• to assess the patient’s orthopedic status (degree of 1. Times or events linking smoking to a negative out-
mobility, etc.) come must be identified.
• to evaulate the patient’s cardiovascular and pul- 2. A target date for quitting smoking must be established.
monary function 3. Health-care personnel must maintain follow-up
communication with former program participants.
(1:1090), (16:879).
Although exercising is desirable and is a healthful ac-
IIIG2a tivity, it is not a critical element in a smoking-cessation
program.
228. C. Upper-body endurance should progressively last up
to 20 minutes in a pulmonary-rehabilitation program. (1:448), (16:883–886, 1093–1094).
Most patients cannot perform arm exercises for more
than a few minutes initially. With progressive condition- IIIG2a
ing, however, upper-body endurance should increase. 231. B. A transdermal nicotine patch helps overcome the
(1:1096), (16:882–883). widespread problem of incorrect chewing of nicotine
gum. The 24-hour nicotine patch potentially reduces
IIIG2a early-morning cravings and can reduce the potential of
early-morning relapses.
229. B. Exercise is an essential element of a pulmonary-
rehabilitation program. Within the exercise prescrip- Both the nicotine gum and transdermal nicotine patch
tion, a target heart rate is established. The target heart produce nicotine blood levels intended to reduce or
rate is based on the results of the rehabilitation pa- eliminate major withdrawal symptoms while avoiding
tient’s initial exercise assessment. A formula called the pleasure-inducing levels. If pleasure-inducing lev-
Karvonen’s formula is used to calculate the target heart els would be achieved with the use of nicotine gum or
rate from knowing the patient’s peak heart rate and with a transdermal patch, the smoker would not with-
resting heart rate. A factor of 0.6 is also included in the draw from using nicotine.
equation, which is shown as follows: Patients maintain the need for counseling while either
THR = [(PHR  RHR) 0.6)] + RHR chewing nicotine gum or wearing the transdermal
nicotine patch.
where,
(1:448), (16:883, 1093–1094).
THR = target heart rate (beats/min.)
PHR = peak heart rate (beats/min.) IIIG2c
RHR = resting heart rate (beats/min.)
232. C. Generally, home-oxygen concentrators are checked
In this problem, the patient’s PHR was 135 beats/min., on a monthly basis. Routine maintenance each month
and the RHR was 80 beats/min. Therefore, includes the following procedures:
THR = [(135 beats/min.  80 beats/min.)0.6] 1. cleaning and/or replacing the filters
+ 80 beats/min. 2. confirming the delivered FIO2
= [(55 beats/min.)0.6] + 80 beats/min. 3. checking the alarm systems

= 33 beats/min. + 80 beats/min. If the concentrator is dusty, cleaning the exterior surfaces

with a damp cloth might be necessary. The location of
= 113 beats/min. the concentrator is important. Air should be allowed to
A Borg scale from 0 to 10 is sometimes used for pa- flow around the concentrator. Clothes, towels, or sup-
tients who are severely impaired and who have a THR plies stacked around the concentrator can eventually and
as an unreliable index of the level of work they per- adversely affect the machine’s performance.
form. The Borg scale is also used for patients who can- (1:1117).
not monitor their heart rate. The scale is based on the
patient’s perception of dyspnea or exertion. A score of IIIG2c
4 to 8 within the 0 to 10 scale is a realistic goal.
233. D. An oxygen concentrator is expected to deliver at least
(1:1094), (16:883). 85% oxygen at a flow rate of 5 liters/min. The CRT does

380 Chapter 5: Therapeutic Procedures

 not have to change the flow rate to achieve a higher oxy- tem is not essential, however. Suitable heating and
gen concentration, because 85% or more oxygen should cooling of the patient’s room is imperative.
be sensed by the oxygen analyzer. When this criterion is
(1:1110, 1122).
not met, the cause is usually exhausted pellet canisters
(necessitating the replacement of the device).
IIIG2c
(1:1117). 235. A. Ventolin (albuterol) is a beta-two agonist (adrenergic
bronchodilator). Atrovent (ipratropium bromide) is an
IIIG2c anticholinergic bronchodilator. Both medications in-
duce bronchodilatation; however, they do so in different
234. C. Because home-care ventilators are electrically op-
areas of the tracheobronchial tree and at different times
erated, the patient’s home must have a reliable and suf-
following inhalation. An anticholinergic bronchodilator
ficient electrical supply. Overall, amperage and
has its effects in the more central, large airways. The
electrical grounding must also be considered. Suitable
adrenergic bronchodilators, on the other hand, preferen-
batteries and/or generators should be in place to pro-
tially act on beta-two receptors located in the large and
vide a backup power source in the event of a power
small airways. Based on this difference, some clinicians
outage. Furthermore, the local power company must
believe the anticholinergic bronchodilator should be ad-
be informed of the critical need for continued power
ministered before the beta-two agonist.
service so that during power outages, preference can
be given to the patient’s home when power is being re- In terms of onset of action, beta-two agonists are more
stored. rapid than the anticholinergic bronchodilators. Based
on this consideration, some clinicians believe the beta-
The power supply is critical, because other devices
two agonist should be given before the anticholinergic
such as portable suction equipment, I.V. pumps, and
bronchodilator.
electric-powered beds demand an electrical source.
Similar considerations are also in order when a patient No clinical evidence exists lending credence to either se-
who will require an oxygen concentrator in the home quence of MDI usage. Moreover, the advent of Com-
is about to be discharged. bivent, an MDI dispensing 18 µg ipratropium bromide and
90 µg of albuterol per puff, has resolved this controversy.
The home’s heating/cooling system is an important
consideration. A central heating/air conditioning sys- (8:138–139).

Chapter 5: Therapeutic Procedures 381

 References
1. Scanlan, C., Spearman, C., and Sheldon, R., Egan’s 12. Koff, P., Eitzman, D., and New, J., Neonatal and Pedi-
Fundamentals of Respiratory Care, 7th ed., Mosby- atric Respiratory Care, 2nd ed., Mosby-Year Book,
Year Book, Inc., St. Louis, MO, 1999. Inc., St. Louis, MO, 1993.
2. Kacmarek, R., Mack, C., and Dimas, S., The Essen- 13. Branson, R., Hess, D., and Chatburn, R., Respiratory
tials of Respiratory Care, 3rd ed., Mosby-Year Book, Care Equipment, J. B. Lippincott, Co., Philadelphia,
Inc., St. Louis, MO, 1990. PA, 1995.
3. Shapiro, B., Peruzzi, W., and Kozlowska-Templin, R., 14. Darovic, G., Hemodynamic Monitoring: Invasive and
Clinical Applications of Blood Gases, 5th ed., Mosby- Noninvasive Clinical Application, 2nd ed., W. B. Saun-
Year Book, Inc., St. Louis, MO, 1994. ders Company, Philadelphia, PA, 1995.
4. Malley, W., Clinical Blood Gases: Application and 15. Pierson, D., and Kacmarek, R., Foundations of Respi-
Noninvasive Alternatives, W. B. Saunders Co., ratory Care, Churchill Livingston, Inc., New York,
Philadelphia, PA, 1990. 1992.
5. White, G., Equipment Theory for Respiratory Care, 16. Burton, et al., Respiratory Care: A Guide to Clinical
3rd ed., Delmar Publishers, Inc., Albany, NY, 1999. Practice, 4th ed., Lippincott-Raven Publishers,
6. Ruppel, G., Manual of Pulmonary Function Testing, Philadelphia, PA, 1997.
7th ed., Mosby-Year Book, Inc., St. Louis, MO, 1998. 17. Wojciechowski, W., Respiratory Care Sciences: An In-
7. Barnes, T., Core Textbook of Respiratory Care Prac- tegrated Approach, 3rd ed., Delmar Publishers, Inc.,
tice, 2nd ed., Mosby-Year Book, Inc., St. Louis, MO, Albany, NY, 1999.
1994. 18. Aloan, C., Respiratory Care of the Newborn and
8. Rau, J., Respiratory Care Pharmacology, 5th ed., Child, 2nd ed., Lippincott-Raven Publishers, Philadel-
Mosby-Year Book, Inc., St. Louis, MO, 1998. phia, PA, 1997.
9. Wilkins, R., Sheldon, R., and Krider, S., Clinical As- 19. Dantzker, D., MacIntyre, N., and Bakow, E., Compre-
sessment in Respiratory Care, 3rd ed., Mosby-Year hensive Respiratory Care, W. B. Saunders Company,
Book, Inc., St. Louis, MO, 1995. Philadelphia, PA, 1998.
10. Pilbeam, S., Mechanical Ventilation: Physiological 20. Farzan, S., and Farzan, D., A Concise Handbook of
and Clinical Applications, 3rd ed., Mosby-Year Book, Respiratory Diseases, 4th ed., Appleton & Lange,
Inc., St. Louis, MO, 1998. Stamford, CT, 1997.
11. Madama, V., Pulmonary Function Testing and Car-
diopulmonary Stress Testing, 2nd ed., Delmar Publish-
ers, Inc., Albany, NY, 1998.

382 Chapter 5: Therapeutic Procedures

 CHAPTER 6 CHAPTER 1 POSTTEST

The posttest contained here represents your final phase in preparing for the Entry-Level Examination. The content
of the posttest parallels that which you will encounter on the Entry-Level Examination offered by the NBRC. The
posttest consists of 140 test items that match the Entry Level Examination Matrix. The content areas included on the
posttest are as follows:

• Clinical Data (25 items)

• Equipment (36 items)
• Therapeutic Procedures (79 items)

Remember to allow yourself three uninterrupted hours for the posttest and to use the answer sheet located on the
next page. Score the posttest soon after you complete it. Begin reviewing the posttest analyses and references and
the NBRC matrix designations as soon as you have a reasonable block of time available.

383
 Posttest Answer Sheet
DIRECTIONS: Darken the space under the selected answer.

A B C D A B C D
1. ❏ ❏ ❏ ❏ 25. ❏ ❏ ❏ ❏
2. ❏ ❏ ❏ ❏ 26. ❏ ❏ ❏ ❏
3. ❏ ❏ ❏ ❏ 27. ❏ ❏ ❏ ❏
4. ❏ ❏ ❏ ❏ 28. ❏ ❏ ❏ ❏
5. ❏ ❏ ❏ ❏ 29. ❏ ❏ ❏ ❏
6. ❏ ❏ ❏ ❏ 30. ❏ ❏ ❏ ❏
7. ❏ ❏ ❏ ❏ 31. ❏ ❏ ❏ ❏
8. ❏ ❏ ❏ ❏ 32. ❏ ❏ ❏ ❏
9. ❏ ❏ ❏ ❏ 33. ❏ ❏ ❏ ❏
10. ❏ ❏ ❏ ❏ 34. ❏ ❏ ❏ ❏
11. ❏ ❏ ❏ ❏ 35. ❏ ❏ ❏ ❏
12. ❏ ❏ ❏ ❏ 36. ❏ ❏ ❏ ❏
13. ❏ ❏ ❏ ❏ 37. ❏ ❏ ❏ ❏
14. ❏ ❏ ❏ ❏ 38. ❏ ❏ ❏ ❏
15. ❏ ❏ ❏ ❏ 39. ❏ ❏ ❏ ❏
16. ❏ ❏ ❏ ❏ 40. ❏ ❏ ❏ ❏
17. ❏ ❏ ❏ ❏ 41. ❏ ❏ ❏ ❏
18. ❏ ❏ ❏ ❏ 42. ❏ ❏ ❏ ❏
19. ❏ ❏ ❏ ❏ 43. ❏ ❏ ❏ ❏
20. ❏ ❏ ❏ ❏ 44. ❏ ❏ ❏ ❏
21. ❏ ❏ ❏ ❏ 45. ❏ ❏ ❏ ❏
22. ❏ ❏ ❏ ❏ 46. ❏ ❏ ❏ ❏
23. ❏ ❏ ❏ ❏ 47. ❏ ❏ ❏ ❏
24. ❏ ❏ ❏ ❏ 48. ❏ ❏ ❏ ❏

384 Chapter 6: Posttest

49. ❏ ❏ ❏ ❏ 78. ❏ ❏ ❏ ❏
50. ❏ ❏ ❏ ❏ 79. ❏ ❏ ❏ ❏
51. ❏ ❏ ❏ ❏ 80. ❏ ❏ ❏ ❏
52. ❏ ❏ ❏ ❏ 81. ❏ ❏ ❏ ❏
53. ❏ ❏ ❏ ❏ 82. ❏ ❏ ❏ ❏
54. ❏ ❏ ❏ ❏ 83. ❏ ❏ ❏ ❏
55. ❏ ❏ ❏ ❏ 84. ❏ ❏ ❏ ❏
56. ❏ ❏ ❏ ❏ 85. ❏ ❏ ❏ ❏
57. ❏ ❏ ❏ ❏ 86. ❏ ❏ ❏ ❏
58. ❏ ❏ ❏ ❏ 87. ❏ ❏ ❏ ❏
59. ❏ ❏ ❏ ❏ 88. ❏ ❏ ❏ ❏
60. ❏ ❏ ❏ ❏ 89. ❏ ❏ ❏ ❏
61. ❏ ❏ ❏ ❏ 90. ❏ ❏ ❏ ❏
62. ❏ ❏ ❏ ❏ 91. ❏ ❏ ❏ ❏
63. ❏ ❏ ❏ ❏ 92. ❏ ❏ ❏ ❏
64. ❏ ❏ ❏ ❏ 93. ❏ ❏ ❏ ❏
65. ❏ ❏ ❏ ❏ 94. ❏ ❏ ❏ ❏
66. ❏ ❏ ❏ ❏ 95. ❏ ❏ ❏ ❏
67. ❏ ❏ ❏ ❏ 96. ❏ ❏ ❏ ❏
68. ❏ ❏ ❏ ❏ 97. ❏ ❏ ❏ ❏
69. ❏ ❏ ❏ ❏ 98. ❏ ❏ ❏ ❏
70. ❏ ❏ ❏ ❏ 99. ❏ ❏ ❏ ❏
71. ❏ ❏ ❏ ❏ 100. ❏ ❏ ❏ ❏
72. ❏ ❏ ❏ ❏ 101. ❏ ❏ ❏ ❏
73. ❏ ❏ ❏ ❏ 102. ❏ ❏ ❏ ❏
74. ❏ ❏ ❏ ❏ 103. ❏ ❏ ❏ ❏
75. ❏ ❏ ❏ ❏ 104. ❏ ❏ ❏ ❏
76. ❏ ❏ ❏ ❏ 105. ❏ ❏ ❏ ❏
77. ❏ ❏ ❏ ❏ 106. ❏ ❏ ❏ ❏

Chapter 6: Posttest 385

 A B C D A B C D
107. ❏ ❏ ❏ ❏ 124. ❏ ❏ ❏ ❏
108. ❏ ❏ ❏ ❏ 125. ❏ ❏ ❏ ❏
109. ❏ ❏ ❏ ❏ 126. ❏ ❏ ❏ ❏
110. ❏ ❏ ❏ ❏ 127. ❏ ❏ ❏ ❏
111. ❏ ❏ ❏ ❏ 128. ❏ ❏ ❏ ❏
112. ❏ ❏ ❏ ❏ 129. ❏ ❏ ❏ ❏
113. ❏ ❏ ❏ ❏ 130. ❏ ❏ ❏ ❏
114. ❏ ❏ ❏ ❏ 131. ❏ ❏ ❏ ❏
115. ❏ ❏ ❏ ❏ 132. ❏ ❏ ❏ ❏
116. ❏ ❏ ❏ ❏ 133. ❏ ❏ ❏ ❏
117. ❏ ❏ ❏ ❏ 134. ❏ ❏ ❏ ❏
118. ❏ ❏ ❏ ❏ 135. ❏ ❏ ❏ ❏
119. ❏ ❏ ❏ ❏ 136. ❏ ❏ ❏ ❏
120. ❏ ❏ ❏ ❏ 137. ❏ ❏ ❏ ❏
121. ❏ ❏ ❏ ❏ 138. ❏ ❏ ❏ ❏
122. ❏ ❏ ❏ ❏ 139. ❏ ❏ ❏ ❏
123. ❏ ❏ ❏ ❏ 140. ❏ ❏ ❏ ❏

386 Chapter 6: Posttest

 Posttest Assessment
DIRECTIONS: Each of the questions or incomplete statements is followed by four suggested answers or com-
pletions. Select the one that is best in each case, then blacken the corresponding space on the an-
swer sheets found in the front of this chapter. Good luck.

1. Which of the following ventilator-setting adjustments C. minimization of hyperventilation

would tend to lower auto-PEEP? D. reduction of the likelihood of arterial vasospasm
I. lengthening the expiratory time
5. A CRT is asked to assess the total arterial oxygen con-
II. increasing the ventilatory rate
tent (CaO2) of a patient who arrives in the emergency
III. increasing the pressure limit
department in respiratory distress following an at-
IV. shortening the inspiratory time
tempted suicide via inhalation of exhaust fumes from
A. I, III, IV an automobile. Which of the following values would
B. I, II, III only not be useful in the assessment of this patient’s total
C. I, IV only arterial oxygen content?
D. II, III, IV only
A. results from a co-oximeter
B. oxygen saturation from a pulse oximeter
2. Which of the following solutions should be used as a
C. hemoglobin concentration
diluent when collecting a tracheal sputum specimen
D. dissolved arterial oxygen tension
from an intubated patient?
A. sterile water 6. While analyzing the oxygen concentration produced
B. hypertonic saline by a jet nebulizer set at an FIO2 of 0.40, the CRT no-
C. bacteriostatic normal saline tices that the oxygen analyzer indicates 55%. What
D. normal saline should the CRT do to correct the problem?
A. Increase the size of the air-entrainment port.
3. A 5 ft. 4 in., 110-lb. female is receiving mechanical
B. Ensure that the capillary tube is unobstructed.
ventilation. The ventilator settings include:
C. Empty the water trap and tubing of condensate.
• SIMV rate: 10 breaths/min. D. Increase the flow rate set on the flow meter.
• tidal volume: 600 cc
• FIO2: 0.40 7. The usual range for suction pressure for nasal, oral,
• PEEP: 5 cm H2O pharyngeal, and tracheobronchial suctioning in adults
is ____________ mm Hg.
Her ABG and acid-base data reveal:
A. –10 to –50
PO2 80 torr
B. –20 to –60
PCO2 20 torr
C. –80 to –120
pH 7.32
D. –130 to –170
HCO3̄ 10 mEq/liter
What should the CRT do in this situation?
8. An adult woman who has liver failure is brought into
A. Do nothing, because no ventilator changes are the hospital and has an arterial blood sample obtained
necessary. from her radial artery for co-oximetry. When a pulse
B. Reduce the tidal volume. oximeter is attached to her index finger, the CRT no-
C. Reduce the SIMV rate. tices that the SpO2 reading is significantly lower than
D. Eliminate the PEEP. the SaO2 reading from a co-oximeter. Which of the fol-
lowing conditions could not potentially cause this dif-
4. Which of the following conditions is not an indication ference to occur?
for the injection of 2% lidocaine before an arterial
A. heavily pigmented skin
puncture procedure?
B. nail polish
A. relief of patient anxiety C. elevated bilirubin levels
B. enhancement of blood flow into the syringe D. low cardiac output (C.O.) states

Chapter 6: Posttest 387

 9. A 33-year-old motorcycle accident victim weighing A. 550–650 cc
115 lbs. (IBW) is brought to the emergency department B. 650–750 cc
and is immediately intubated and mechanically venti- C. 750–850 cc
lated with a volume-cycled ventilator. A closed-head D. 850–950 cc
injury is suspected. The ventilator settings include:
14. An infant is receiving 30% oxygen via a blending sys-
• ventilatory rate: 14 breaths/min.
tem with heated humidification through a small-sized
• tidal volume: 700 cc
oxyhood. While performing oxygen rounds, the CRT
• FIO2: 0.30
verifies the correct oxygen concentration but notices
After 20 minutes of mechanical ventilation, ABG and that the flow rate is set inappropriately. What minimal
acid-base data reveal: flow rate range should the CRT maintain to prevent the
accumulation of carbon dioxide?
PO2 100 torr
PCO2 25 torr A. 7–8 L/min.
pH 7.56 B. 9–12 L/min.
HCO 3̄ 22 mEq/liter C. 13–15 L/min.
D. 16–20 L/min.
What should the CRT do at this time?
A. Decrease the ventilatory rate. 15. The technique for maintaining movement of air around
B. Reduce the FIO2. an endotracheal (ET) tube cuff at end inspiration while
C. Reduce the tidal volume. exerting pressure against the tracheal wall during ex-
D. Make no ventilator changes. halation is known as the
A. Flexible cuff technique.
10. The CRT is having a patient perform maximum inspi-
B. Minimal leak technique.
ratory and expiratory pressure maneuvers. What range
C. Occluding volume technique.
of pressure-measuring capabilities should the device
D. Minimal pressure technique.
have?
A. –200 to –250 cm H2O 16. A high-pitched squeal is heard coming from a dispos-
B. –100 to –150 cm H2O able bubble humidifier that is attached to a nasal can-
C. –60 to –100 cm H2O nula. Which of the following conditions would cause
D. 0 to –100 cm H2O this sound to develop?
A. The flow rate is inadequate for the patient’s inspi-
11. Following administration of a mucolytic, the CRT aus-
ratory demands.
cultates bilateral wheezing. What action should the
B. The humidifier’s water level is low, preventing ad-
CRT recommend?
equate humidification.
A. discontinuing therapy C. The bed is on part of the cannula’s tubing.
B. administering a bronchodilator D. The patient’s SpO2 is lower than 85%.
C. adding chest physiotherapy (CPT) to the thera-
peutic regime 17. A post-op thoracotomy patient weighing 72 kg is re-
D. performing nasotracheal suctioning covering from pulmonary edema caused by residual
heart problems, as well as from being given too much
12. Which of the following factors is not considered a sig- fluid in the postoperative period. The patient is cur-
nificant source of error when interpreting a pulse- rently being ventilated with the following settings:
oximeter reading?
• mode: IMV
A. presence of fetal hemoglobin • ventilatory rate: 6 breaths/min.
B. patient movement • tidal volume: 850 ml
C. presence of carboxyhemoglobin • PEEP: 15 cm H2O
D. bright, external, ambient lights • FIO2: 0.40
• pressure support: 5 cm H2O above baseline
13. A 65-year-old female COPD patient with a 40-pack-
He is breathing comfortably with a total ventilatory
per-year smoking history is experiencing an acute ex-
rate of 14 breaths/min. His ABGs on these settings in-
acerbation and requires mechanical ventilation. The
dicate:
patient appears to weigh about 125 lbs. Within which
tidal volume range should the initial tidal volume be PO2 148 mm Hg
established? PCO2 38 mm Hg

388 Chapter 6: Posttest

 pH 7.39 to 83%. Which of the following actions is (are) most
HCO 3̄ 24 mEq/liter appropriate for the CRT to take?
I. Withdraw the suction catheter.
What change in ventilator settings should the CRT rec-
II. Postoxygenate with 100% oxygen for a minimum
ommend at this time?
of one minute.
A. Decrease the FIO2 to 0.35. III. Deflate the cuff.
B. Decrease the ventilatory rate to 4 breaths/min.
A. III only
C. Decrease the PEEP to 10 cm H2O.
B. I, II only
D. Extubate the patient.
C. II, III only
D. I, II, III
18. A 165-lb (IBW) patient is receiving pressure-support
ventilation at a level of 5 cm H2O. The CRT has ob-
22. After discontinuing a post-op thoracotomy patient
tained the following data on this patient:
from mechanical ventilation, the CRT is preparing to
• PIP: 50 cm H2O process the reusable ventilator circuitry. The patient
• static pressure: 30 cm H2O was mechanically ventilated for only 24 hours. What
• tidal volume: 750 cc method of infection control should the CRT use?
• static compliance: 25 ml/cm H2O
A. low-level disinfection
• mechanical peak inspiratory flow rate: 80 L/min.
B. intermediate-level disinfection
• patient peak inspiratory flow rate: 40 L/min.
C. high-level disinfection
What level of pressure support should this patient re- D. sterilization
ceive?
23. Which of the following combinations of ventilator set-
A. 5 cm H2O
tings will provide an I:E ratio of 1:2?
B. 10 cm H2O
C. 15 cm H2O I. TI 1.0 sec.; ventilatory rate 20 breaths/min.
D. 20 cm H2O II. TI 1.0 sec.; ventilatory rate 24 breaths/min.
III. TI 0.6 sec.; ventilatory rate 24 breaths/min.
19. The systolic pressure noted as the blood-pressure cuff IV. TI 0.5 sec.; ventilatory rate 40 breaths/min.
is deflated while auscultating an artery indicates
A. II only
which of the following physiologic events?
B. I, IV only
A. the force exerted during contraction of the left C. II, III only
ventricle D. I, II, IV only
B. the force exerted during contraction of the right
ventricle 24. A 120-lb (IBW) female is receiving controlled mechan-
C. the force developed during ventricular diastole ical ventilation. The ventilator settings are as follows:
D. the force generated during the contraction of the
• ventilatory rate: 10 breaths/min.
right atrium
• tidal volume: 800 cc
• FIO2: 0.50
20. A nurse urgently summons a CRT to check an electri-
cally powered ventilator that does not seem to be de- ABG and acid-base data reveal:
livering breaths to a patient. The CRT depresses the
PO2 85 torr
manual breath button several times, but to no avail.
PCO2 60 torr
What should be done next?
pH 7.30
A. Wait to see whether the timer will deliver a con- HCO 3̄ 29 mEq/liter
trolled breath.
This patient is a post-op thoracotomy and has had no
B. Push the manual sigh button to see whether that
pre-existing pulmonary disease. The physician has re-
will work.
quested that the CRT make the appropriate ventilator-
C. Call to the department for someone to bring an-
setting changes to achieve an arterial PCO2 of 40 torr.
other ventilator.
What should the CRT do at this time?
D. Disconnect the patient from the ventilator and
manually ventilate him. A. Increase the ventilatory rate to 15 breaths/min.
B. Increase the tidal volume to 900 cc.
21. While performing ET suctioning on a mechanically C. Add 50–100 cc of mechanical dead space.
ventilated patient, the CRT notices that the SpO2 falls D. Decrease the peak flow rate.

Chapter 6: Posttest 389

25. Bag-mask ventilation is being performed on an el- 30. A physician prescribes a bronchodilator to be admin-
derly, edentulous patient. In the process, the CRT has istered via intermittent nebulization to a patient who is
difficulty maintaining a seal with the mask around the receiving mechanical ventilation. Where in the venti-
patient’s face. What should she do in this situation? lator circuit should the CRT place the nebulizer?
A. Pinch the patient’s nose closed and use the re- A. along the inspiratory limb, about 18 inches from
maining three fingers to press the mask over the the Y adaptor
patient’s mouth. B. along the inspiratory limb at the humidifier
B. Forego hyperextending the patient’s head and C. anywhere along the inspiratory limb
neck to use both hands to secure a tight seal. D. between the ventilator and the humidifier
C. Pull the patient’s cheeks up to the sides of the
mask and have another person compress the bag. 31. The CRT is summoned to the ICU to correct a patient’s
D. Close the patient’s mouth with two fingers and ventilator that has been alarming. The CRT notices
use the remaining three fingers to secure the mask that the PIP has increased and that the plateau pressure
over the patient’s nose. has remained constant since the last time the ventilator
was checked. The monitor reveals a decrease in the pa-
26. While reading the chest roentgenogram of an 18-year- tient’s oxygen saturation. The appropriate action to
old asthmatic, the CRT notices the presence of infil- take at this time is to
trates in the superior basal segments. Which postural
A. suction the airway.
drainage position would be appropriate?
B. have the nurse sedate the patient.
A. flat supine C. administer a bronchodilator.
B. Trendelenburg prone D. change the ventilator.
C. Trendelenburg lateral on the patient’s left side
D. flat prone 32. Which of the following factors will cause the PIP on a
mechanical ventilator to increase?
27. A CRT approaches a patient’s bedside and notices a
I. an increase in the tubing compliance
nurse about to suction a tracheotomized patient’s
II. excess moisture accumulation in the breathing
oropharynx with a Yankauer suction device while the
circuit
suction pressure gauge is indicating –60 mm Hg. What
III. kinks in the tubing
should the CRT do at this time?
A. I, II only
A. Inform the nurse that she is using the wrong suc-
B. I, III only
tion device.
C. II, III only
B. Inform the nurse that she is using inadequate suc-
D. I, II, III
tion pressure.
C. Inform the nurse that she should suction the tra-
33. A cachectic appearance is often associated with what
cheostomy tube first.
pathology?
D. Allow the nurse to proceed, because the situation
is normal. A. Guillain–Barré
B. Acquired Immunodeficiency Syndrome (AIDS)
28. What is the consequence if a patient’s tidal volume de- C. pneumonia
creases below the critical displacement volume while D. Pickwickian syndrome
on a demand-flow CPAP system?
34. What is the rationale for continuously assessing and
A. auto-PEEP develops
monitoring a patient’s cardiac rhythm?
B. pulmonary elastance increases
C. metabolic alkalosis results I. to evaluate the patient’s need for continued care
D. carbon dioxide retention occurs II. to ensure the patient’s tolerance to the therapy
III. to assess cardiac rhythm
29. A CRT is alone and is ventilating a patient with a man- IV. to quickly determine dysrhythmias
ual resuscitator. She determines that the patient is not
A. I, II, III only
receiving sufficient ventilation. Her appropriate action
B. II, III only
is to
C. I, IV only
A. perform mouth-to-mask. D. I, II, III, IV
B. use a demand valve instead of the manual resusci-
tator. 35. The CRT has placed a nonrebreather mask set at 12
C. squeeze the bag harder. L/min. on a cyanotic patient. Shortly, a nurse states
D. perform mouth-to-mouth. that she has reduced the flow rate to 2 L/min. because

390 Chapter 6: Posttest

 the patient has COPD. What is the best course of ac- 40. The use of PEEP in conjunction with mechanical ven-
tion for the CRT to take at this time? tilation might produce which of the following effects?
A. Maintain the nonrebreather mask at 2 L/min. I. increased FRC
B. Replace the mask with a nasal cannula at 2 L/min. II. increased intracranial pressure
and inform the physician. III. decreased the P(A-a)O2
C. Request an order for an ABG. IV. prevention of atelectasis
D. Readjust the flow rate to 12 L/min. and inform the V. decreased venous return
physician.
A. I, II, III, IV, V
B. I, III, IV, V only
36. Which condition(s) represents a potential complication C. I, IV, V only
associated only with a patient having a nasotracheal D. II, IV only
tube in place as opposed to an oral ET tube?
I. otitis media 41. Auscultation of the chest could provide the CRT with
II. acute sinusitis information related to all of the following conditions
III. epiglottitis EXCEPT
IV. tracheitis I. presence of a pneumothorax.
A. II only II. an airway obstruction.
B. I, III, IV only III. presence of lung cancer.
C. II, IV only IV. decrease in lung compliance.
D. I, II only A. III, IV only
B. I, III, IV only
37. For a patient receiving mechanical ventilation, which C. I, II only
I:E ratio would most adversely influence the C.O.? D. II, III only
A. 2:1 42. As a CRT in the ICU is about to measure the intracuff
B. 1:1.5 pressure of a ventilator patient, she notices that the digi-
C. 1:2 tal cuff-pressure manometer is broken. She then devises a
D. 1:4 system using a sphygmomanometer, oxygen-connecting
tubing, a three-way stopcock, and a 10-cc syringe. The
38. During initiation of an IPPB treatment, the CRT notices patient’s cuff is inflated to the minimal occluding vol-
that no aerosol is flowing from the mouthpiece when ume. Each time the stopcock is attached to the spring-
the machine is in the ON position. Which of the fol- loaded valve, she notices a significant intracuff pressure
lowing conditions would cause this situation to occur? loss equivalent to approximately 3 cc of volume. Which
I. a capillary tube obstruction of the following actions would correct this problem?
II. a broken baffle I. Shorten the length of the oxygen-connecting tubing.
III. an inadequate inspiratory pressure II. Replace the sphygmomanometer with an aneroid
IV. a jet obstruction manometer.
A. I, IV only III. Prepressurize the manometer.
B. II, III only IV. Overinflate the cuff by 3 cc to compensate for the
C. I, II, IV only volume loss.
D. I, II, III, IV A. I, II only
B. IV only
39. For which of the following dysrhythmias is cardiover- C. II, III only
sion applied? D. I, III only
I. ventricular fibrillation 43. The physician wishes to prescribe a medication that will
II. atrial fibrillation thin tenacious respiratory secretions. Which of the fol-
III. atrial flutter lowing pharmacologic agents should the CRT suggest?
IV. ventricular tachycardia
A. acetylcystine
A. I, II only B. guaifenesin
B. II, III only C. cromolyn sodium
C. I, IV only D. ethyl alcohol
D. I, III, IV only

Chapter 6: Posttest 391

44. A patient who is receiving mechanical ventilation via • total ventilatory rate: 15 breaths/min.
a time-cycled ventilator is experiencing respiratory • FIO2: 0.40
acidosis. How should the CRT correct this situation?
His ABG values are as follows:
A. Increase the inspiratory time.
PO2 160 torr
B. Increase the peak inspiratory flow rate.
PCO2 26 torr
C. Adjust the sensitivity control to make the ventila-
pH 7.49
tor more responsive to the patient.
D. Increase the high-pressure limit. What change should the CRT suggest at this point?
A. decreasing the tidal volume to 600 ml
45. After setting up a simple oxygen mask on a patient, the
B. decreasing the machine rate to 4 breaths/min.
CRT notes that no sound comes from the nonheated
C. administering a sedative agent
bubble-diffusion humidifier when the oxygen tubing to
D. changing to IMV mode
the simple mask is kinked. What does this condition
indicate?
49. The CRT has obtained the following ventilatory data
A. that the water level in the humidifier is too high from a spontaneously breathing neuromuscular-
B. that the humidifier’s pop-off valve is not func- disease patient who weighs 87 kg and is 188 cm tall:
tioning
tidal volume: 350 ml
C. that the oxygen flow rate is set too low
respiratory rate: 28 breaths/min.
D. that the oxygen-delivery system has no leaks
vital capacity: 900 ml
maximum inspiratory pressure: –15 cm H2O
46. Gloves should be worn during oral suctioning for pa-
Room air arterial blood gas data reveal:
tients who have which of the following diagnoses?
PaO2 55 torr
I. tuberculosis
PaCO2 65 torr
II. hepatitis B
pH 7.11
III. bacterial pneumonia
HCO 3̄ 20 mEq/L
IV. chest trauma
B.E. 4mEq/L
A. I only
What should the CRT recommend for this patient at
B. I, II only
this time?
C. I, II, III only
D. I, II, III, IV A. 30% oxygen via an air-entrainment mask
B. continued monitoring of the patient’s ventilatory
47. A hemodynamically unstable cardiac-monitored patient status
who is receiving an FIO2 of 0.4 via an air-entrainment C. endotracheal intubation and mechanical ventilation
mask has the following signs and symptoms: D. endotracheal intubation and a Briggs adaptor de-
livering 30% oxygen
• shortness of breath
• hypotension 50. What is the most reliable indication that rescue breath-
• signs of congestive heart failure ing is inflating the patient’s lungs?
• decreased level of consciousness
• persistent chest pain A. observing that the patient has lost much of his
blue color
The patient’s heart rate is 160 beats/min. What action B. observing the rise and fall of the patient’s chest
should the CRT take at this time? C. perceiving little resistance as inflation is performed
A. Increase the FIO2 by using a partial rebreathing D. observing responsive pupils
mask.
B. Cardiovert the patient. 51. A 5 ft.-10 in., 190-lb, male COPD patient who has CO2
C. Administer 1 to 1.5 mg/kg I.V. of lidocaine. retention is receiving SIMV with the following settings:
D. Administer 10 to 20 g/kg/min. of dopamine I.V. • SIMV rate: 12 breaths/min.
• tidal volume: 850 cc
48. A 70-kg man is being mechanically ventilated on the • FIO2: 0.30
following settings:
• mode: assist-control The patient’s ABG and acid-base data indicate:
• VT: 800 ml PO2 60 torr
• machine rate: 6 breaths/min. PCO2 47 torr

392 Chapter 6: Posttest

 pH 7.52 A. I, II, III, IV, V
HCO3̄ 37 mEq/liter B. II, III, IV, V only
C. I, II, III, V only
What should the CRT do at this time?
D. III, IV only
A. Decrease the SIMV rate.
B. Decrease the tidal volume. 56. A CRT receives an order to initiate incentive spirome-
C. Decrease the FIO2. try on a 43-year-old woman who has had a cholecys-
D. Add expiratory retard. tectomy. Which of the following statements provides
the best explanation of the goal of this therapy to the
52. A COPD patient exercises at home by walking for 12 patient?
minutes. Calculate this patient’s target heart rate based
A. This treatment will make sure you get out of the
on the following data:
hospital quickly.
peak heart rate: 135 beats/min. B. This treatment will encourage you to breathe
resting heart rate: 80 beats/min. deeply and help prevent lung complications after
your operation.
A. 113 beats/min.
C. The therapy will prevent you from getting pneu-
B. 135 beats/min.
monia after your surgery.
C. 160 beats/min.
D. The treatment prevents postoperative atelectasis
D. 215 beats/min.
and helps you mobilize retained secretions
53. Which of the following humidifiers is most capable of through a sustained maximal inspiration.
providing an absolute humidity of 44 mg/liter at 37ºC
when used to deliver high-flow oxygen via a CPAP 57. The CRT is attempting to wean a patient from me-
system? chanical ventilation who has been continuously me-
chanically ventilated for two months. Numerous
A. heated Bennett cascade weaning trials have proved unsuccessful because the
B. jet humidifier patient could not sustain spontaneous breathing.
C. condensing humidifier Which of the following ventilatory methods should the
D. wick humidifier CRT recommend at this time?
54. On Tuesday during the day shift, a CRT set up a 40% A. a Briggs adaptor set at 30% oxygen and having
Venturi mask on a patient in the emergency depart- 100 cc of reservoir tubing
ment. The patient was diaphoretic, tachypneic, and B. pressure-support ventilation
tachycardiac and exhibited an increased work of C. CPAP
breathing. The CRT was asked by a respiratory-care D. volume-control ventilation with continuous
student how the effectiveness of the oxygen therapy mandatory ventilation
will be evaluated. The CRT replied that on Thursday,
when the student returns, a positive response to treat- 58. Which of the following conditions might cause an in-
ment would be crease in the PIP reading on a ventilator pressure
manometer?
I. An improvement in vital signs.
II. A decrease in the FIO2. I. adding 4 cm H2O PEEP
III. A decrease in the work of breathing. II. reducing the FIO2
IV. A decrease in breath sounds. III. developing a pneumothorax
IV. eliminating expiratory resistance to the system
A. I, II, III only V. decreasing the sensitivity control
B. II, III, IV only
C. I, III, IV only A. I, II, III, IV, V
D. I, II, IV only B. II, IV only
C. I, III, IV only
55. When selecting a manual resuscitator for use in the D. I, III only
clinical setting, which of the following features would
be desired? 59. What term describes discontinuous adventitious sounds
that resemble that of hairs being rubbed together?
I. self-inflating
II. capability of providing 100% oxygen A. rales
III. nonrebreathing valve mechanism B. rhonchi
IV. universal connector on the resuscitator valve C. crackles
V. pressure limit with override capability D. wheezes

Chapter 6: Posttest 393

60. An asthmatic patient is receiving a bland aerosol ultra- C. The analyzer’s sensor should be placed near the
sonic nebulization treatment. He suddenly becomes exhalation port.
short of breath and has trouble breathing. What should D. The humidifier needs to be turned off.
be done to treat this patient?
A. Terminate the ultrasonic treatment and leave the 65. A 50-kg, 30-year-old jockey has sustained multiple
patient alone. fractures with a severe flail chest after being thrown
B. Administer a bronchodilator. from his racehorse and trampled on the track. He has
C. Continue the treatment. been pharmacologically paralyzed and sedated while
D. Terminate the treatment and notify both the nurse receiving mechanical ventilation in the control mode,
and physician. with a tidal volume of 600 cc and ventilatory rate of 10
breaths/min. for the past three days. This morning, the
61. A patient is receiving volume-controlled, continuous paralyzing agents were discontinued, and the physi-
mechanical ventilation. The CRT notices that the PIP cian requested conversion to the SIMV mode with a
is reaching 70 cm H2O. To reduce the PIP, the CRT frequency of 6 breaths/min. for a weaning trial. Three
lowers the inspiratory flow rate. What effect will this hours later, the CRT makes the following assessment:
setting change have on the patient’s ventilatory status?
• frequency (total): 28 breaths/min.
A. The mean airway pressure will increase. • spontaneous VT: 130 cc
B. The inspiratory time will decrease. • expired minute ventilation: 6.46 L/min.
C. The I:E ratio will increase.
Physical findings include
D. The tidal volume will increase.
• paradoxical chest-wall movement
62. An 80-kg patient was initially set up to receive a tidal • agitation and tachycardia
volume of 800 cc on volume-controlled, continuous me- • accessory-muscle use
chanical ventilation. The initial PIP and plateau pres-
sure (Pplateau) are as follows: The physician asks the CRT for her suggestions on
weaning this patient. Which recommendation would
PIP 30 cm H2O be most appropriate?
Pplateau 15 cm H2O
A. Assess ventilatory mechanics.
One hour after the initiation of mechanical ventilation, B. Switch from mechanical to spontaneous ventila-
these measurements were tion via a T-piece at a slightly higher FIO2.
PIP 40 cm H2O C. Switch to weaning by pressure-support ventilation.
Pplateau 25 cm H2O D. Discontinue the weaning trial.

How is the patient’s ventilation affected by these changes?

66. Upon auscultation of the patient’s chest, the CRT notes
A. The inspiratory time increases. the presence of soft, muffled, low-pitch sounds pri-
B. The tidal volume remains constant. marily during inspiration on both sides of the chest.
C. The mean airway pressure remains constant. What do these findings suggest?
D. The I:E ratio increases.
A. pneumonia
63. A diagnosis of pneumonia is best confirmed by which B. bronchiolitis
diagnostic procedure? C. COPD
D. normal breath sounds
A. chest radiograph
B. arterial blood gas
C. spirometry 67. A 42-kg, 55-year-old trauma victim is brought to the
D. thoracotomy emergency department in respiratory distress. The pa-
tient is immediately intubated and ventilated at the fol-
64. A CRT approaches the bedside of a mechanically ven- lowing settings:
tilated patient and notices that a polarographic ana- • mode: assist-control
lyzer has been placed in-line on the inspiratory limb of • ventilatory rate: 12 breaths/min.
the circuitry between the humidifier and the patient • tidal volume: 500 ml
wye. What should she do at this time? • FIO2: 1.0
A. Nothing needs to be done, because this situation is
ABG data 30 minutes later reveal:
acceptable.
B. The analyzer needs to be relocated between the PO2 150 torr
ventilator and the humidifier. PCO2 55 torr

394 Chapter 6: Posttest

 pH 7.30 C. cystic fibrosis
HCO 3̄ 17 mEq/liter D. pneumonia
What recommendation is appropriate for the CRT to
73. The use of nasal or mask CPAP might help accomplish
make?
which of the following therapeutic goals?
A. Increase the ventilatory rate by 2 breaths/min.
I. elimination of obstructive sleep apnea
B. Institute 5 cm H2O PEEP.
II. elimination of central sleep apnea
C. Increase the tidal volume to 600 ml.
III. alleviation of snoring
D. Do nothing; allow the patient to acclimate to me-
IV. reduction in episodes of sudden infant death syn-
chanical ventilation.
drome (SIDS)
68. The physician wishes to screen a patient for evidence A. I, III only
of nocturnal hypoventilation before referral to a sleep B. II, III only
lab. What technique should the CRT recommend? C. I, II, III only
D. IV only
A. serial ABGs
B. pulse oximetry
74. A COPD patient is receiving an aerosolized 10% Mu-
C. plethysmography
comyst treatment. During the treatment, the patient
D. transcutaneous PCO2 monitoring
complains of dyspnea. What should the CRT do in this
situation?
69. Which of the following evaluation procedures should
the CRT perform during IPPB therapy? A. Stop the 10% Mucomyst treatment, then give a
metaproterenol treatment.
I. chest inspection
B. Increase the concentration of Mucomyst to 20%.
II. maximum expiratory pressure
C. Add cromolyn sodium to the nebulizer.
III. bilateral auscultation of the chest
D. Add NaHCO3 to the nebulizer.
IV. listen for bruits
A. I, II, III only 75. Which condition(s) might preclude effective closed-
B. II, III, IV only chest cardiac massage?
C. I, III only
I. mediastinal shift
D. I, IV only
II. vertebral abnormalities
III. crushed chest injury
70. Calculate the amount of water per unit volume of air IV. tension pneumothorax
(absolute humidity or content) when the humidity
deficit is 15.7 mg/liter and the capacity is 44.0 A. IV, only
mg/liter. B. II, IV only
C. I, III only
A. 5.5 mg/liter D. I, II, III, IV
B. 13.3 mg/liter
C. 15.7 mg/liter 76. A patient is being weaned from SIMV. The patient
D. 28.3 mg/liter meets all of the criteria for weaning; however, he
seems to be requiring a substantial inspiratory effort to
71. Which of the following positions would minimize hy- obtain gas flow from the demand-flow system. What
poxemia in a mechanically ventilated patient who is should the CRT do at this time?
trying to sleep and has a left-lower lobe pneumonia?
A. Decrease the SIMV rate.
A. semi-Fowler’s B. Increase the tidal volume.
B. supine Trendelenburg C. Switch to continuous-flow IMV.
C. left-lateral decubitus D. Switch to controlled mechanical ventilation.
D. right-lateral decubitus
77. Which of the following complications might result if a
72. Copious, foul-smelling, bloody, and purulent sputum tracheotomized patient maintains a humidity deficit?
that separates into three distinct layers upon standing
I. decreased ciliary function
is characteristic of which disease condition?
II. dried and tenacious retained secretions
A. asthma III. mucous plugging of the artificial airway
B. bronchiectasis IV. bleeding in the airways

Chapter 6: Posttest 395

 A. I, II, III only pH 7.23
B. III, IV only HCO3̄ 24 mEq/liter
C. I, II only
What ventilator adjustments would be appropriate to
D. I, III only
normalize this patient’s ABGs?
78. An infant in the NICU is receiving continuous-flow I. increasing the FIO2 to 0.50
nasal CPAP at 10 cm H2O. The CRT notices that the II. increasing the PEEP to 8 cm H2O
system pressure is fluctuating between almost 0 cm III. increasing the PIP to 26 cm H2O
H2O and 15 cm H2O. Which of the following factors IV. increasing the ventilatory rate to 35 breaths/min.
might account for this situation?
A. I, III, IV only
I. The demand valve is increasing the infant’s work B. III, IV only
of breathing. C. II, III, IV only
II. The pressure-relief valve is stuck in the closed po- D. I, II only
sition.
III. The infant is crying. 82. A CRT attaches a pneumatic nebulizer that is half full
IV. The gas flow rate through the system is too high. of sterile, distilled water to an airflow meter. After set-
ting the flow meter to 10 L/min., the CRT notes that no
A. I, III, IV only mist is leaving the nebulizer. Which of the following
B. I, II only conditions is the most likely cause for this problem?
C. II, III only
D. III only A. inadequate flow for a pneumatic nebulizer
B. insufficient water level in the reservoir
79. Following aerosolization of a mucolytic agent, the C. a disconnected capillary tube
CRT notes that the patient’s cough produces white D. a missing nebulizer baffle
sputum. What action should the CRT recommend?
83. The CRT is asked to establish the level of PEEP that cor-
A. continuing mucolytic therapy responds with the best oxygenation status for an ARDS
B. changing to an aerosolized bronchodilator patient. Serial analyses of arterial and mixed-venous
C. adding CPT to the treatment regime blood samples are performed at different PEEP levels,
D. discontinuing the aerosol treatment and the C.O. is recorded as illustrated in Table 6-1.
Table 6-1: Optimum PEEP trial data
80. Calculate a patient’s V̇A when given the following data:
• heart rate: 100 beats/min. PEEP Arterial Mixed Cardiac
• blood pressure: 140/85 torr Level Oxygen Venous Output
(cm H2O) Saturation Saturation (L/min.)
• stroke volume: 50 cc
• V̇A/Q̇C: 0.6:1.0 5.0 87% 61% 3.0
A. 0.012 L/min. 10.0 90% 66% 3.5
12.5 92% 71% 3.4
B. 0.6 L/min.
15.0 95% 61% 3.1
C. 30.0 ml/sec. 20.0 88% 57% 2.7
D. 3.0 L/min.

81. A 1.5-kg premature newborn who is receiving time- What level of PEEP should the CRT recommend?
cycled, pressure-limited mechanical ventilation for A. 10.0 cm H2O
respiratory distress syndrome has the following set- B. 12.5 cm H2O
tings: C. 15.0 cm H2O
• FIO2: 0.40 D. 20.0 cm H2O
• PIP: 21 cm H2O
84. A patient is receiving an FIO2 of 0.4 via a Briggs adap-
• PEEP: 5 cm H2O
tor operating at a source gas flow of 10 liters/minute,
• ventilatory rate: 30 breaths/min.
with 50 cc of reservoir tubing at the distal end. The pa-
• inspiratory time: 0.5 sec.
tient has an inspiratory flow rate of 55 liters/minute.
ABGs obtained 20 minutes after mechanical ventila- What action should the CRT take in this situation?
tion was initiated reveal
A. Use a double flow meter setup with a blender.
PO2 67 torr B. Switch to an air entrainment mask set at an FIO2
PCO2 58 torr of 0.4.

396 Chapter 6: Posttest

 C. Increase the flow rate on the flow meter to 15 88. A CRT is performing endotracheal suctioning on a pa-
liters/min. tient who is receiving mechanical ventilation. During
D. Add another 50 cc of reservoir tubing. the procedure, the CRT looks at the ECG monitor and
notices the pattern shown in Figure 6-1.
85. All of the following conditions can cause an erroneous
What should the CRT do at this time?
pulse oximeter reading EXCEPT
A. Ventilate the patient with a manual resuscitator.
A. ambient bright lights.
B. Administer a precordial thump.
B. recent exposure to carbon monoxide.
C. Administer 100% oxygen.
C. low perfusion states.
D. Resume mechanical ventilation.
D. increased alveolar dead space.
89. A 33-year-old, 6-foot, 180-lb male patient is receiving
86. A CRT is obtaining lung mechanics data on a 70-kg
mechanical ventilation in the IMV mode following a
male patient who is intubated and might require me-
near-drowning incident. The patient has been receiving
chanical ventilation. Table 6-2 shows the values ob-
ventilatory assistance for two days. The current venti-
tained.
lator settings are as follows:
Table 6-2: Lung mechanics data
• mechanical ventilator rate: 2 breaths/min.
Measurement Result • mechanical tidal volume: 850 cc
• FIO2: 0.40
Tidal volume (VT) 500 ml • PEEP: 8 cm H2O
Minute ventilation (V̇E) 18 L/min.
Vital capacity (VC) 800 ml The spontaneous ventilatory rate and tidal volume are
Maximum inspiratory as follows:
pressure (MIP) –18 cm H2O
• spontaneous ventilatory rate: 10 breaths/min.
• spontaneous tidal volume: 550 cc
Which of these ventilatory measurements would indi- ABG data at this time are:
cate that the patient does not require mechanical ven-
tilation? PO2 79 torr
PCO2 36 torr
A. tidal volume pH 7.36
B. minute ventilation HCO 3̄ 20 mEq/liter
C. vital capacity
D. maximum inspiratory pressure Assessment of ventilatory mechanics reveals:
• vital capacity: 2.0 liters
87. A patient who has an inspiratory flow demand of 35 • maximum inspiratory pressure: –35 cm H2O
L/min., an abnormal ventilatory pattern, and an FIO2
requirement of 0.35 is administered a Venturi mask set What should the CRT do at this time?
on 35% O2, operating at 5 L/min. Which of the follow- A. Increase the PEEP.
ing statements is true regarding this delivery system? B. Increase the IMV rate.
A. The patient will receive an FIO2 less than 0.35. C. Administer CPAP.
B. The patient will receive an FIO2 greater than 0.35. D. Extubate the patient and administer oxygen via an
C. The patient will receive an FIO2 of 0.35. aerosol mask at 40% oxygen.
D. The patient should be switched to a nasal cannula
at 4 L/min.

Figure 6-1: Lead II ECG.

Chapter 6: Posttest 397

90. A 35-year-old male who is sedated and orally intu- 93. The CRT is administering an ultrasonic nebulization
bated with an 8.5 mm I.D. ET tube is being mechani- treatment to a patient. Unknown to the CRT, a leak in
cally ventilated via a pressure-cycled ventilator. The the diaphragm occurs between the nebulizer compart-
CRT has been called to the patient’s room because the ment and the couplant chamber. What problem might
nurse has noticed that the ventilator will not cycle off. result from this leak?
Which of the following conditions might have caused
A. increased nebulization caused by overfilling of
this occurrence?
the chamber
I. The ET tube cuff has ruptured. B. decreased nebulization resulting from an increase
II. The ET tube is too large for this patient. in water level
III. The ET tube has slipped down into the right- C. an electric current leak produced by an electrical
mainstem bronchus. short caused by the nebulizer
IV. There is a slow leak in the pilot balloon. D. contamination of the solution being nebulized
A. I only
94. The technique recommended for initially establishing
B. III only
an airway in an unconscious patient is
C. I, II only
D. I, IV only A. oral intubation.
B. extension of the neck.
91. How should a maximum inspiratory pressure of –30 cm C. cricothyroidotomy.
H2O obtained from an intubated, critically ill adult patient D. placement of a nasal trumpet.
who is receiving mechanical ventilation be interpreted?
95. The CRT enters the room of a post-op thoracotomy pa-
A. The measurement might be falsely low because
tient to evaluate the patient’s use of a three-chambered,
the patient is intubated.
flow-oriented incentive spirometry (IS) device. In
B. A –30 cm H2O might predict successful weaning
demonstrating the procedure, the patient holds the IS
from a mechanical ventilation for some patients.
device vertically and inhales to the point whereby the
C. The measurement might be falsely low if taken
ball in each chamber momentarily rises to the top.
between FRC and RV.
What should the CRT do at this time?
D. A –30 cm H2O might indicate adequate muscle
endurance. A. Inform the patient that balls in only two chambers
should rise.
92. The ABG results for an alert, spontaneously breathing B. Instruct the patient to hold the IS device at a 45º
patient who is determined to have capillary shunting angle.
secondary to a diffuse pneumonia are as follows: C. Coach the patient to sustain the inspiratory effort
long enough for all three balls to remain elevated
PO2 55 torr
for three seconds.
PCO2 38 torr
D. Do nothing, because the patient is performing the
pH 7.41
therapeutic procedure correctly.
HCO 3̄3 24 mEq/liter
The patient is receiving an FIO2 of 0.80. Which of the 96. A patient who is receiving a tidal volume of 700 cc via
following would be the most appropriate therapy to mechanical ventilation has had an order for PEEP. In
improve the PaO2? attempting to determine the appropriate level of PEEP,
the CRT has performed a PEEP evaluation study
A. Initiate aggressive CPT and incentive spirometry.
shown in Table 6-3.
B. Apply CPAP.
C. Intubate and increase the FIO2. Which level of PEEP has benefited this patient most?
D. Initiate IPAP.

Table 6-3: PEEP trial data

Time PEEP BP C.O. HR PaO2 C.O.  CaO2

2 P.M. 0 cm H2O 100/70 torr 5.0 L/min. 98 bpm 70 torr 925 ml/min.
2:30 P.M. 5 cm H2O 100/70 torr 4.9 L/min. 100 bpm 85 torr 937 ml/min.
3 P.M. 7 cm H2O 100/70 torr 4.7 L/min. 97 bpm 84 torr 926 ml/min.
3:30 P.M. 10 cm H2O 100/70 torr 4.4 L/min. 95 bpm 78 torr 824 ml/min.
4 P.M. 12 cm H2O 96/70 torr 4.1L/min. 93 bpm 75 torr 760 ml/min.

398 Chapter 6: Posttest

 A. 5 cm H2O 103. A 70-kg, 54-year-old woman who is recovering from a
B. 7 cm H2O total hysterectomy performed 18 hours ago has been
C. 10 cm H2O ordered to receive incentive spirometry. During a fol-
D. 12 cm H2O low-up visit by the CRT, the patient demonstrates her
effort by inspiring rapidly on her Triflo device and
97. A CRT is instructing a patient in the care and operation raising all three balls. Based on this information, the
of an MDI. What is the best method to instruct the pa- CRT calculates her inspired volume to be less than 15
tient to determine how full the MDI is? ml/kg. Which intervention is the most appropriate?
A. Keep a log of the number of puffs administered. A. Discontinue incentive spirometry.
B. Weigh the canister on a small kitchen scale. B. Initiate postural drainage and percussion.
C. Float the canister in a bowl of water. C. Recommend a volume-oriented incentive spirometer.
D. Shake the canister. D. Recommend switching to IPPB.

98. The development of bronchospasm following admin- 104. During an IPPB treatment, the needle on the pressure
istration of a beta-two agonist is an example of what manometer deflects significantly counterclockwise at
type of adverse reaction? the beginning of inspiration. What action should the
A. toxicity CRT take to correct this situation?
B. anaphylaxis A. Decrease the inspiratory pressure.
C. idiosyncracy B. Increase the peak flow.
D. tachyphylaxis C. Increase the sensitivity.
D. Decrease the sensitivity.
99. Which of the following actions will cause a decrease
in the oxygen delivery with a manual resuscitator? 105. What would be the most likely cause of a gradual in-
A. rapid ventilatory rate crease in the FIO2 delivered to a patient by a pneu-
B. use of an oxygen reservoir matic nebulizer?
C. increased oxygen-input flow A. a decrease in wall-oxygen pressure
D. increased bag-refill time B. a decrease in the patient’s minute ventilation
C. a fall in the reservoir water level
100. The CRT walks into an adult patient’s room and finds D. an accumulation of water in the tubing
the patient apparently comatose. The CRT immedi-
ately notices that the electrocardiogram (ECG) moni-
106. In examining the anterioposterior chest X-ray for
tor indicates cardiac standstill. What should his first
proper ET tube placement, which of the following de-
response be in this situation?
scriptions is not appropriate for ET tube positioning in
A. Administer a precordial thump in an attempt to the adult patient?
get the heart pumping again.
A. The tube tip should be at the level of the aortic
B. Perform bag-mask ventilation.
knob.
C. Try to awaken the patient.
B. The tube tip should be at least 3 cm above the ca-
D. Begin one-rescuer resuscitation measures.
rina with the cuff well below the glottis.
C. The tube tip should be within 2 cm of the carina.
101. A change in the color of indicator tape used to monitor
D. The tube tip should be between T2 and T4.
sterilization indicates that
A. Sterilization has not occurred. 107. A post-operative gastric stapling patient is receiving
B. Additional time is needed for sterilization. mechanical ventilatory support with the following set-
C. Conditions for sterilization have been met. tings:
D. Sterilization is 100% effective.
• tidal volume: 1,200 ml
102. A patient who is hospitalized for croup requires what • FIO2: 0.40
type of isolation procedure (other than standard pre- • PEEP: 5 cm H2O
cautions)? ABGs and pulse-oximetry data reveal:
A. respiratory precautions PO2 195 torr
B. contact precautions PCO2 25 torr
C. airborne precautions pH 7.55
D. droplet precautions SpO2 100%

Chapter 6: Posttest 399

 Which of the following conditions reflect the ABG and 110. The CRT has just received a call from the Life Flight
oximetry data? team regarding the arrival of a full-term newborn
within 30 minutes. The infant has been wearing a 30%
I. absolute shunting
aerosol mask during the transport with acceptable
II. excessive alveolar ventilation
SpO2 values. Which of the following delivery devices
III. inadequate alveolar ventilation
should the CRT set up to prepare for the infant’s ar-
IV. normal PaO2 for this FIO2
rival?
A. I, III only
A. mist tent with oxygen supplied from a nebulizer
B. II, IV only
B. oxyhood with an oxygen blender
C. I, II only
C. radiant warmer
D. III, IV only
D. incubator with the red flag up and supplied by
oxygen at 10 L/min.
108. Which of the following questions would determine a
patient’s orientation?
111. Which of the following descriptions best describes
I. How long has it been since you received a breath- how to use a in-line cuff manometer for determining
ing treatment? the pressure within the cuff of an ET tube? Use Figure
II. What is your full name? 6-2 as a reference.
III. What state do you live in?
A. Have a three-way communication among the sy-
IV. Where are you right now?
ringe, manometer, and cuff and add air while
V. What day is today?
watching the manometer.
A. I, IV only B. Add air to the cuff, turn the stopcock so that it is
B. II, III, V only off to the syringe, and measure the cuff pressure.
C. II, IV, V only C. Add air to the manometer line, turn the stopcock
D. II, III, IV, V only so that it is off to the syringe, and then measure
the pressure.
109. A post-cholecystectomy patient is complaining of pain D. Add air to the cuff, remove the syringe, and attach
radiating down his left arm. He is diaphoretic and his the cuff manometer directly to the pilot balloon.
SpO2 is 88%. What immediate action is indicated at
this time? 112. The CRT notices a patient using an MDI with a spacer
attached. The patient is tilting back her head and ap-
A. cardiopulmonary resuscitation
pears to be struggling to coordinate her inspiration
B. mechanical ventilation
with the actuation of the device. She is taking volumes
C. low-flow oxygen therapy
slightly larger than her tidal volume, however. What
D. oxygen via a nonrebreather mask
should the CRT do at this time?

In-line manometer

cm H2O

Air

ET tube Three-way stopcock

pilot balloon

Figure 6-2

400 Chapter 6: Posttest

 A. Have the patient continue practicing and encour- was for her to take a bronchodilator before the cro-
age her in the process. molyn sodium. The patient has tried this sequence, but
B. Remove the spacer, because it appears to be hin- no improvement was noted. In fact, she now has a low-
dering the patient. grade fever and a rash on her trunk. What modification
C. Instruct the patient to keep her head level, actuate to therapy should the CRT recommend?
the MDI, and inspire slowly to TLC.
A. Discontinue the use of cromolyn sodium.
D. Instruct the patient to breathe in slowly to TLC
B. Give the drug less often.
and breath hold for five seconds.
C. Instruct the patient to take the medication more
slowly.
113. The CRT has recently extubated a patient. A short time
D. Increase the dosage of bronchodilator.
later, the patient has difficulty breathing, and inspira-
tory stridor is audible with the unaided ear. What 118. Which technique would be best to re-expand areas of
should the CRT recommend at this time? mild atelectasis in an alert, cooperative, post-operative
A. a lateral neck radiograph patient?
B. nebulization of a beta-two agonist A. encouraging deep breathing
C. reintubation of the patient and administration of B. IPPB
40% oxygen via a T-piece C. nasotracheal suctioning
D. nebulization of racemic epinephrine D. chest percussion
114. A completely paralyzed Guillain–Barré patient has just 119. While the high-pressure alarm on a mechanical venti-
been placed on a kinetic therapy or lateral-rotation bed. lator is sounding, the CRT hears gurgling coming from
The nurse reports frequent occurrences of the high- the airway of an adult patient. The CRT is preparing to
pressure alarm on the ventilator. Which of the follow- suction the patient but is alerted by the nurse that this
ing situations should the CRT suspect as the cause of patient often has premature ventricular contractions
this problem? (PVCs). What can the CRT do to minimize the risk of
A. mobilization of large amounts of retained secre- this dysrhythmia during suctioning?
tions A. Instill 5 cc of normal saline down the ET tube to
B. stretching of the ventilator tubing thin the secretions.
C. development of a pneumothorax B. Inject 60 mg of lidocaine I.V. before suctioning to
D. agitation and anxiety prevent this dysrhythmia.
C. Preoxygenate the patient with 100% oxygen be-
115. A fenestrated tracheostomy tube can be used for which fore suctioning to reduce myocardial instability.
of the following reasons? D. Have the nurse massage the patient’s carotid
I. to assess a patient’s ability to be extubated artery during the suctioning procedure to mini-
II. to decrease the incidence of infection mize the risk of PVCs.
III. to enable the patient to speak
120. A croupette is set up and is operating at 7 L/min., pow-
IV. to decrease the incidence of postextubation edema
ered by 100% oxygen. The CRT is concerned about
A. I, IV only maintaining an adequate oxygen concentration as well
B. I, III only as minimizing carbon dioxide levels within the tent.
C. II, IV only Which of the following options would be appropriate?
D. II, III, IV only
A. Maintain the flow as indicated.
B. Increase the flow to 12 L/min.
116. What range of oxyhemoglobin saturation measured C. Add supplemental flow into the canopy from an
via pulse oximetry is most appropriate for premature ultrasonic nebulizer that is powered by com-
infants who are receiving supplemental oxygen? pressed air.
A. 95%–100% D. Switch the patient to an open-top tent.
B. 90%–94%
C. 85%–89% 121. The CRT is evaluating the flow waveform generated
D. 80%–84% from a mechanical ventilator and notices that the flow
during exhalation remains below the baseline when the
ventilator cycles to inspiration. What is the signifi-
117. An asthmatic patient who has recently been instructed
cance of the expiratory flow as shown in Figure 6-3?
on the use of cromolyn sodium complains of throat ir-
ritation, cough, and a general tight feeling in her chest A. The sensitivity control should be adjusted.
upon administration of the drug. The recommendation B. The patient’s lung compliance increased.

Chapter 6: Posttest 401

 C. The patient’s airway resistance increased. hemidiaphragm without consolidation. Which of the
D. Auto-PEEP has developed. following therapeutic goals apply to this patient?
I. treating atelectasis
II. mobilizing secretions
Flow

III. improving inspiratory muscle performance

Time
IV. lowering blood pressure

Figure 6-3: Flow-time tracing. A. I, II only

B. I, III only
122. What is the most probable cause of tachycardia ob- C. II, III only
served during an ET suctioning procedure? D. III, IV only

A. hypoxemia 126. Which of the following descriptions explains the princi-

B. vagal stimulation ple of operation for a polarographic oxygen electrode?
C. mucosal trauma
D. increased intracranial pressure A. The electrode consumes oxygen in an oxidation-
reduction reaction to produce an electric current.
123. A hospital has decided to make mouth-to-mask resus- B. The electrode measures the magnetic field created
citation devices available in every patient care area. by oxygen molecules.
The CRT is consulted by the purchasing department to C. The electrode measures the potential difference
evaluate available devices and to make a recommen- across a polypropylene membrane.
dation for purchase. Which of the following factors D. The electrode generates light intensity propor-
should be considered essential for an “ideal” mouth- tional to the oxygen concentration in the sampling
to-mask resuscitation device? chamber.

I. easily conforming to the patient’s face, providing 127. Mechanical ventilation has just been instituted on a
a tight seal post-op cardiac transplant patient. To evaluate the ef-
II. offering low resistance to gas flow, with minimal fectiveness of mechanical ventilation, which assess-
dead space ments should the CRT perform?
III. isolating the rescuer from the patient
I. Check response to verbal stimuli.
IV. being transparent
II. Auscultate the chest.
A. I, III only III. Monitor the tidal volume.
B. I, II, IV only IV. Obtain an ABG.
C. II, III, IV only
A. IV only
D. I, II, III, IV
B. II, III only
C. I, III, IV only
124. During CPT, a mechanically ventilated chest-trauma
D. II, III, IV only
patient requiring vigorous pulmonary hygiene be-
comes anxious. His heart rate, ventilatory rate, and PIP
128. Calculate the I:E ratio given the following respiratory
rise. His SaO2 falls, and PVCs are occasionally noted.
data:
What modifications might enable bronchial hygiene
procedures to be performed on this patient? • ventilatory rate (f): 10 breaths/min.
• inspiratory time (TI): 1 sec.
I. Coordinate CPT with pain medication.
• maximum inspiratory pressure (MIP): –10 mm Hg
II. Perform postural drainage without clapping.
• maximum expiratory pressure (MEP): 40 mm Hg
III. Review the notes to determine whether agitation
is positional. A. 1:4
IV. Paralyze and sedate the patient. B. 1:5
C. 1:6
A. I, III, IV only
D. 1:40
B. I, II, III only
C. I, II only 129. When evaluating an aneroid manometer for accuracy,
D. II, III, IV only the CRT should check the reading on the aneroid
manometer against
125. A previously healthy 50-year-old female has been pre-
scribed incentive spirometry postcholecystectomy. A. a previously calibrated aneroid manometer.
The chest X-ray shows a slight elevation of the right B. a mercury manometer.

402 Chapter 6: Posttest

 C. an electronic transducer. C. that the results might indicate severe airway ob-
D. a calibrated “super syringe”. struction and that ABG analysis should be per-
formed
130. During CPR, an FIO2 of 1.0 is required. The equip- D. that the results might be low because the patient
ment available is a 2-liter resuscitation bag with a performed the test in a seated position
reservoir and an oxygen flow meter with tubing. To
maximize the FIO2 delivery, the CRT should 135. What is the correct sequence of events to yield an ef-
fective cough reflex?
I. Adjust the flow meter to 8 L/min.
II. Ventilate the patient at as high a ventilatory rate as I. expulsion
possible. II. compression
III. Use a short inspiratory time. III. irritation
IV. Allow as much of the reservoir to refill as possible. IV. inspiration
A. I, II, III only A. I, II, III, IV
B. III, IV only B. IV, III, II, I
C. I, III, IV only C. III, IV, II, I
D. I, II, III, IV D. IV, III, I, II

131. When measuring cuff pressures, the CRT obtains an 136. When instructing a COPD patient in diaphragmatic
intracuff pressure reading of 32 cm H2O. Which of the breathing, the CRT should place a hand in the
following changes should the CRT perform first? ____________ region and instruct the patient to inhale
so that the hand is lifted.
A. Increase the pressure to 35 cm H2O.
B. Use the minimal leak technique to decrease the A. midsternal
pressure to 27 cm H2O. B. subcostal
C. Do nothing, because this reading is acceptable. C. epigastric
D. Recommend a larger ET tube. D. lower abdominal

132. What percent of the vital capacity can normally be ex- 137. Which of the following therapeutic modalities is ap-
haled in the first second of a FVC maneuver? propriate to treat a patient who has chronic moderate
A. 45% asthma with an FEV1 of 75%?
B. 55% A. incentive spirometry for the prevention of atelec-
C. 65% tasis
D. 75% B. an MDI with an anti-inflammatory agent
C. postural drainage for the mobilization of secre-
133. A patient complains that she does not like her breath- tions
ing treatments and asks the CRT to “go away.” What D. IPPB therapy to improve the distribution of venti-
should the CRT do in this situation? lation
A. Explain to the patient that she has to take her treat-
ments because the doctor ordered them for her. 138. Following routine tracheostomy care and cleaning, the
B. Ask the patient’s sister to convince her to take the CRT notices the cardiac rhythm depicted in Figure
treatment. 6-4. Which interpretation corresponds with the ECG
C. Notify the patient’s nurse and document the re- tracing shown?
fusal in the chart. A. sinus bradycardia
D. Administer the therapy as ordered and record the B. sinus arrhythmia
results in the chart. C. sinus arrest
D. premature atrial contraction
134. If spirometry data provided an FEV1 of 63% of pre-
dicted and an FEV1% of 65%, what would be an appro-
139. A predominantly nasally breathing patient is about to
priate evaluation of this patient’s pulmonary function?
receive a bronchodilator via continuous nebulization in
A. that the results are normal a small-volume nebulizer operating at 8 liters/minute.
B. that the results might indicate moderate airway The physician asks the CRT to optimize the nebuliza-
obstruction and that a postbronchodilator FVC be tion of the drug. Which of the following actions should
performed the CRT recommend?

Chapter 6: Posttest 403

 Figure 6-4: ECG tracing

I. Increase the flow rate of the gas operating the 140. The temperature monitor of a ventilator system indi-
small-volume nebulizer. cates a reading of 46ºC. The temperature alarm is
II. Use a small-volume nebulizer with a mechanism sounding. What is the first action that should be taken?
enabling intermittent nebulization.
A. The ventilator should be turned off.
III. Use heliox at the same flow rate to operate the
B. The alarm should be silenced.
small-volume nebulizer.
C. The patient should be disconnected from the
IV. Have the patient use a mouthpiece to deliver the
ventilator.
drug to the airways.
D. The thermistor reading should be turned down.
A. II only
B. II, III only
C. III, IV only
D. I, II, IV only

404 Chapter 6: Posttest

 Posttest: Matrix Categories
1. IIIE1i(1) 36. IIIA2b(1) 71. IIIC2c 106. IB7a
2. IIIA2b(3) 37. IIID7 72. IB1b 107. IIID3
3. IIIE2d 38. IIB1k 73. ID1b 108. IB5a
4. IC1c 39. IIIF2 74. IIIE3 109. IIA1a
5. IC1c 40. IIIC2a 75. IIIF1 110. IIIE1e(2)
6. IIB2a(2) 41. IB4a 76. IIIC2c 111. IIA1m(1)
7. IIIB2b 42. IIB1f(2) 77. IIIB2c 112. IIB2p
8. IIA2h(4) 43. IIIE3 78. IIB1a(3) 113. IIIE3
9. IIIE1i(1) 44. IIIE1i(1) 79. IIIE3 114. IIID4
10. IIA1m(1) 45. IIB1a(1) 80. IB10b 115. IIA1f(3)
11. IIIE3 46. IIIA3 81. IIIC1d 116. IC1a
12. IC1a 47. IIIF2 82. IIB1c 117. IIIE3
13. IIIC1d 48. IIIE1i(1) 83. IIIC2a 118. IIIC1a
14. IIIC1e 49. IIIC1d 84. IIIE1e(1) 119. IIIB2b
15. IIID9 50. IIIF1 85. IIB1h(4) 120. IIB1j
16. IIB1b 51. IIIC1f 86. IC1b 121. IIIA2e
17. ID1d 52. IIIG2a 87. IIA1a(2) 122. IIIA2b(4)
18. IIIE1i(1) 53. IIA1b 88. IIIC2c 123. IIA1d
19. IB4c 54. IIID5 89. IIIC2a 124. IIIA2d
20. IIB1e(1) 55. IIA1d 90. IIB1f(2) 125. ID1b
21. IIIC2c 56. IIIA1 91. IC1b 126. IIA1h(5)
22. IIA2 57. IIIE1j 92. IIIC2a 127. IIID7
23. IB1b 58. IIIE1i(1) 93. IIB1c 128. IA1f(2)
24. IIIC1d 59. IB4a 94. IIIB1d 129. IIB1m
25. IIIF1 60. IIIE1f 95. IIB1k 130. IIIF1
26. IIIB2a 61. IIIE1i(1) 96. IIIE2d 131. IIIE1g(4)
27. IIB1a(3) 62. IIIE1i(1) 97. IIA1q 132. IA1d
28. IIIC2a 63. IA1e 98. IIIA2b(1) 133. IIIA2b(1)
29. IIB2d 64. IIB1h(5) 99. IIB1d 134. IC2a
30. IIIB2c 65. IIIC1h 100. IIIF1 135. IIIB2d
31. IIIB2b 66. IB4a 101. IIA2 136. IIIC1a
32. IIB1j(1) 67. IIID4 102. IIIA3 137. ID1c
33. IB1a 68. IA2f 103. IIIE1c 138. IIID5
34. IIID5 69. IIIC1b 104. IIIE1b(1) 139. IIIE1d(3)
35. IIB1a(1) 70. IIB1b 105. IIB1c 140. IIIE1d(3)

Chapter 6: Posttest 405

Table 6-4: Posttest—entry-level examination matrix scoring form
Entry-Level Examination Posttest Posttest Items Posttest Content
Content Area Item Number Answered Correctly Area Score

I. Clinical Data
A. Review data in the patient record and 63, 68, 128, 132 __ × 100 = ___ %
4
recommend diagnostic procedures.
B. Collect and evaluate clinical information. 19, 23, 33, 41, 59, __ × 100 = ___ %
10 __ × 100 = ___ %
66, 72, 106, 108
25
C. Perform procedures and interpret results. 4, 5, 12, 86, __ × 100 = ___ %
7
91,116, 134
D. Determine the appropriateness and 17, 73, 125, 137 __ × 100 = ___ %
4
participate in the development of the
respiratory care plan and recommend
modifications.
II. Equipment
A. Select, obtain, and assure equipment 8, 10, 22, 53, 55, __ × 100 = ___ %
13
cleanliness. 87, 97, 101, 109,
111, 115, 123, 126
B. Assemble and check for proper equipment 6, 16, 20, 27, 29, __ × 100 = ___ % __ × 100 = ___ %
23 36
function, identify and take action to correct 32, 35, 38, 42, 45,
equipment malfunctions, and perform 64, 70, 78, 82, 85,
quality control. 90, 93, 95, 99, 105,
112, 120, 129
III. Therapeutic Procedures
A. Explain planned therapy and goals to 2, 36, 46, 56, 98, __ × 100 = ___ %
10
the patient; maintain records and 102, 121, 122, 124,
communication, and protect the patient 133
from noscomial infection.
B. Conduct therapeutic procedures to 7, 26, 30, 31, 77, __ × 100 = ___ %
8
maintain a patent airway and remove 94, 119, 135
bronchopulmonary secretions.
C. Conduct therapeutic procedures to 13, 14, 21, 24, 28, __ × 100 = ___ %
19
achieve adequate ventilation and 40, 49, 51, 65, 69,
oxygenation. 71, 76, 81, 83, 88,
89, 92, 118, 136
D. Evaluate and monitor patient’s response 15, 34, 37, 54, 67, __ × 100 = ___ % __ × 100 = ___ %
9 79
to respiratory care. 107, 114, 127, 138
E. Modify and recommend modifications 1, 3, 9, 11, 18, 43, __ × 100 = ___ %
25
in therapeutics and recommend 44, 48, 57, 58, 60,
pharmacologic agents. 61, 62, 74, 79, 84,
96, 103, 104, 110,
113, 117, 131, 139,
140
F. Treat cardiopulmonary collapse according 25, 39, 47, 50, __ × 100 = ___ %
7
to BLS, ACLS, PALS, and NRP. 75,100, 130
G. Assist the physician, initiate, and conduct 52 __ × 100 = ___ %
1
pulmonary rehabilitation and home care.

406 Chapter 6: Posttest

 Posttest Answers and Analyses
NOTE: The references listed after each analysis are numbered and keyed to the reference list located at the end of
this section. The first number indicates the text. The second number indicates the page where information
about the questions can be found. For example, (1:114, 187) means that on pages 114 and 187 of reference
1, information about the question will be found. Frequently, you will have to read beyond the page num-
ber indicated to obtain complete information. Therefore, reference to the question will be found either on
the page indicated or on subsequent pages.

IIIE1i(1) lation. The cause of their hyperventilation may be fear,

1. C. Auto-PEEP or intrinsic PEEP occurs when the ex- pain, anxiety, hypoxemia, central nervous system dis-
haled gas is still flowing as the ensuing inspiration be- orders, or metabolic acidosis, however. Generally,
gins. This situation can be rectified by making the when any of these potential causes result in hyperven-
following ventilator-setting adjustments: (1) lengthen- tilation, correction of the primary problem eliminates
ing the expiratory time (TE) by decreasing the ventila- the hyperventilation.
tory rate (f) and increasing the tidal volume, (2) Ventilator adjustments should only be made when the
shortening the inspiratory time (TI) by increasing the hyperventilation is caused by a mechanical problem
peak inspiratory flow, and (3) reducing the ventilatory (i.e., either a tidal volume greater than 15 cc/kg of
rate (f). Other maneuvers that have effectively been IBW or an increased frequency of ventilation). In this
used to decrease auto-PEEP include: (1) using less case, sodium bicarbonate should be administered to
compliant ventilator tubing, (2) instituting applied correct the metabolic acidosis. If hyperventilation con-
PEEP (never more than the auto-PEEP level), and (3) tinues after the metabolic acidosis is treated, consider-
maintaining bronchial hygiene (chest physiotherapy, ation should be given to change ventilator settings
tracheobronchial suctioning, and beta-two agonist ad- (assuming all other nonmechanical hyperventilation
ministration) to prevent frequent changes in compli- causes have been explored).
ance and airway resistance. The physiological effects
of auto-PEEP are the same as those of applied PEEP. (1:287–289), (10:157–158).

(15:905–906), (2:524).
IC1c
IIIA2b(3) 4. B. A local anesthetic (e.g., 0.5% lidocaine) is some-
times given to relieve apprehension, to decrease hy-
2. D. When a diluent is necessary for obtaining a sputum
perventilation associated with fear and pain of the
specimen from an intubated patient, normal saline with-
arterial puncture procedure, to reduce the possibility of
out preservatives should be used. The osmolarity of
vasospasm, and to improve compliance with the possi-
normal saline approximates that of body fluids. The
ble need for additional arterial puncture procedures.
specimen would be damaged by the use of water, hy-
Xylocaine is not given to increase or decrease the ve-
pertonic saline, or bacteriostatic saline. Water and hy-
locity of flow of blood into the syringe.
pertonic saline dilute the sample and cause the cells to
break down because of the osmolarity differences be- (1:340–341), (3:305), (4:10), (16:270).
tween these diluents and the sputum. Bacteriostatic nor-
mal saline inhibits the bacterial growth in the sample. IC1c
(15:626), (15:626), (16:1061). 5. B. Assessment of the total arterial oxygen content
(CaO2) requires the determination of oxygen com-
IIIE2d bined with hemoglobin, as well as that dissolved in the
3. A. This patient is experiencing a metabolic acidosis plasma. The following steps (Steps 1 and 2) outline
accompanied by alveolar hyperventilation (PaCO2 20 how oxygen combined with hemoglobin can be quan-
torr). The hyperventilation is caused by the stimulation tified:
of the peripheral chemoreceptors (carotid and aortic
STEP 1: Determine hemoglobin’s oxygen-carrying
bodies). The stimulant is the rise in the arterial blood
capacity (volumes %) by using the patient’s
H+ ion concentration (pH 7.32).
hemoglobin concentration ([Hb]) and the
Hyperventilation is not uncommon for patients who factor 1.34 ml oxygen per gram of hemoglo-
receive assisted, assist–control, IMV, or SIMV venti- bin.

Chapter 6: Posttest 407

Hb g/100ml blood  1.34 ml O2/g Hb = capacity (vol %) The back pressure exerted at the air-entrainment port
reduces the amount of room air entrained into the gas
STEP 2: Calculate the actual amount of oxygen
flow system in proportion to the source gas (100%
bound to hemoglobin (volumes %); that is,
O2). As a result, more oxygen than room air is delivered.
the content (volumes %), by multiplying the
Hence, the FIO2 increases. The same principles apply if
capacity by the oxygen saturation (SO2).
exceedingly long lengths of aerosol tubing are used in
([Hb]  1.34 ml O2/g Hb) SO2 = content (vol %) the gas-delivery system. According to Poiseuille’s law,
airflow resistance and tube length are directly propor-
or
tional; i.e., as the length of the tube increases, the air-
(capacity)(SO2) = content flow resistance increases.
The next step (Step 3) demonstrates quantifying the Increasing the size of the air-entrainment port de-
amount of oxygen physically dissolved in the plasma. creases the FIO2, because more room air is added to
the gas flow in proportion to the source gas. An ob-
STEP 3: Compute the amount of oxygen physically
structed capillary tube in the jet nebulizer reservoir
dissolved in the plasma by multiplying the
would only decrease the aerosol output and would
PO2 by the factor 0.003 volumes % per mm
have no influence on the FIO2. Increasing the flow
Hg.
rate on the flow meter would not significantly alter
PO2  0.003 vol%/mm Hg = dissolved O2 (vol %) the FIO2, because the amount of room air entrained
would be proportional to the increased source-gas
The last step (Step 4) illustrates how the total arterial
flow rate.
oxygen content (CaO2) can be obtained.
(1:755–756), (13:67–68), (16:391–394), (23:139).
STEP 4: Add the amount of oxygen bound to hemo-
globin (i.e., content [Step 2]) and the IIIB2b
amount of oxygen physically dissolved in
plasma (Step 4). (Note that the units will be 7. C. For routine tracheobronchial suctioning of adults,
volumes %.) the negative pressure should be set within the range of
–80 to –120 mm Hg. Of course, when secretions are
O2 content + dissolved O2 copious and tenacious, the pressure setting might need
= total arterial oxygen content (CaO2) to be changed accordingly. Other factors, however,
Regarding the patient referred to in this question, ob- such as the internal diameter and the length of the suc-
taining an accurate arterial oxygen saturation (SaO2) is tion catheter, influence the resulting flow. Once flow
critical. The CRT must be aware that a pulse oximeter through the catheter becomes turbulent, the negative
does not measure abnormal hemoglobins. A pulse pressure in the suction jar must be increased greatly
oximeter uses only two wavelengths of light (red for before the flow through the catheter is appreciably in-
deoxyhemoglobin; infrared for oxyhemoglobin). Oxy- creased. The recommended suctioning pressures for
hemoglobin and carboxyhemoglobin have similar ab- neonates is a range of –60 to–80 mm Hg, and for pe-
sorbancy measurements for the wavelength of infrared diatric patients, the recommended range is –80 to –100
light. Consequently, in the presence of carbon monox- mm Hg.
ide poisoning (increased carboxyhemoglobin and de- (1:616), (2:430), (16:603), (18:400).
creased oxyhemoglobin), the arterial oxygen saturation
will read erroneously high via a pulse oximeter. There- IIAh4
fore, in cases of carbon monoxide poisoning, pulse
8. C. Pulse oximeter SpO2 readings can be adversely af-
oximetry is of no value in assessing the total oxygen
fected by the following factors:
content.
• nonfunctional hemoglobin
(1:223–225, 361), (9:109–110, 268),
• bright light sources
(16:254–255, 311).
• sunlight
• bilirubin lights
IIB2a(2) • infrared heat lamps
6. C. The FIO2 of a jet nebulizer can increase if conden- • fluorescent lights
sate accumulates in the aerosol tubing. The presence • deeply pigmented skin
of water in the gas-delivery circuit imposes resistance • black, blue, and green nail polish
to the gas flowing from the nebulizer to the patient. • vascular dyes (methylene blue, indigo carmine, and
Consequently, this resistance causes back pressure indocyanine green)
through the tubing toward the air-entrainment port. • low C.O. states

408 Chapter 6: Posttest

 If any of these conditions are present, the pulse oxime- up to 20 seconds, unless adverse effects are observed.
ter is unreliable for monitoring SpO2. The CRT should Early efforts with an uncooperative and unresponsive
check the patient’s fingernails for nail polish before at- patient might not reflect the patient’s true capabilities.
taching the pulse oximeter. Similarly, the fingertip
MEP in relatively healthy subjects can reach as high as
should be shielded from any bright lights. If the patient
250 cm H2O. This measurement is rarely performed at
had any hemodynamic studies performed by using vas-
the patient’s bedside and is usually obtained in the pul-
cular dyes, the CRT should wait for the body to elimi-
monary function laboratory. Patients who are unable to
nate the dyes before relying on the SpO2 measurements.
develop an MEP greater than 40 cm H2O might expe-
(1:359–363, 928–929), (9:267–268), (10:97–98), rience difficulty generating an effective cough. The pa-
(16:310–312), (18:124–125). tient should sustain the maximum expiratory effort for
at least three seconds to reduce the effect of mechani-
IIIE1i(1) cal overshoot.
9. D. This patient is being mechanically ventilated ap- When these maneuvers are performed, the CRT must
propriately for her clinical condition. Because she is ensure that the patient’s cheek muscles are not gener-
suspected of having a closed-head injury, an iatrogenic ating additional pressure. Whenever possible, a 1-mm
respiratory alkalosis is being induced for the purpose diameter leak via a 15-mm long piece of tubing should
of trying to reduce the intracranial pressure (ICP). An be incorporated in the setup to eliminate this effect.
increase in ICP often accompanies a closed-head in-
jury. The application of positive-pressure ventilation in (1:825, 971), (9:257), (10:179–180), (15:555–556),
such cases tends to aggravate the situation by imped- (16:234–235).
ing venous return. The increased mean intrathoracic
pressure from the positive-pressure breathing impairs IIIE3
both abdominal and cranial venous return. 11. B. Auscultation of wheezing indicates the develop-
ment of bronchoconstriction. N-acetylcysteine (Mu-
In an attempt to counteract this phenomenon, the pa-
comyst) is known to induce bronchospasm in some
tient is ordinarily deliberately hyperventilated to an ar-
individuals. A beta-adrenergic bronchodilator is indi-
terial PCO2 of 25–30 torr. The lower-than-normal
cated to treat the bronchospasm.
arterial PCO2 causes cerebral vasoconstriction, thereby
reducing cerebral blood flow. The decreased cerebral (1:580), (8:165–167), (15:818–819).
blood flow helps reduce the ICP. Therefore, in this sit-
uation, no mechanical ventilator changes are neces- IC1a
sary. Maintaining the arterial PO2 above 60 torr in 12. A. Because fetal hemoglobin has similar absorption
these patients is necessary. A drop in the PaO2 causes characteristics to adult hemoglobin, there is reasonable
cerebral vasodilatation. accuracy in pulse-oximetry measurements, even with
(1:828), (2:506), (10:237–239), (15:1095–1102). the presence of large concentrations of fetal hemoglo-
bin. Motion can give false readings, because movement
can be interpreted as a pulsation. The pulse oximeter is
IIA1m(1)
unable to distinguish dysfunctional hemoglobins such
10. A. Because some patients are capable of generating as carboxyhemoglobin (COHb) and methemoglobin
substantial negative and positive pressures when per- (MetHb) from oxyhemoglobin (O2Hb). When dysfunc-
forming the maximum inspiratory and expiratory tional hemoglobins are present, the SpO2 (O2 saturation
pressure (MIP and MEP) maneuvers, the pressure- as determined by pulse oximetry) will be higher than the
measuring device should be capable of measuring a O2 Hb determined by co-oximetry. Finally, bright am-
pressure range between –200 cm H2O and 250 cm bient light will interfere with the capability of the
H2O. A pressure transducer will generally provide this pulse oximeter to assess signals. Interference with am-
pressure-range capability. Although they have a more bient light will lead to an indication of “pulse search”
narrow range, most aneroid pressure manometers are and a blank reading for SpO2. There have been reports
suitable. When the assessed MIP is between –20 and of erroneous readings associated with bright ambient
–30 cm H2O or more negative, the indication is that the light, however.
patient has the ventilatory muscle strength to support
his own spontaneous breathing. The CRT should en- (1:359–363), (9:267–268), (10:97–98), (15:492–494),
courage the patient to maintain this pressure for at (16:310–312).
least three seconds to discount the effect of mechanical
overshoot, which causes the needle of the gauge to IIIC1d
momentarily read higher than the actual measurement. 13. B. Because insufficient information was presented to
The overall duration of the MIP procedure should last determine this patient’s IBW, the apparent body

Chapter 6: Posttest 409

 weight should be used to gauge the initial tidal volume Throughout the ventilatory cycle, pressure against the
setting. Any adjustments thereafter need to be made tracheal mucosa is kept to a minimum, enabling arter-
based on ABG analysis and clinical assessment of the ial and venous blood flow in the tracheal tissue. Excess
patient. pressure on the tracheal wall causes a decrease in the
flow of blood passing the area of the cuff. Decreased
The only information that is available is the apparent
blood flow to this area for an extended time can cause
weight of 125 lbs, which is equivalent to 57 kg (125
tracheal necrosis. Again, air is added to the cuff of the
lbs  2.2 lbs/kg). Using 10–15 cc/kg of IBW as the
ET tube until the airway is sealed, but a minimal
guideline for estimating the initial tidal volume, the
amount of inspired air can still pass around the tube at
preset tidal volume would range somewhere between
peak inspiration.
570 cc and 855 cc.
(1:609–610), (10:255–256), (15:836).
Because this patient has COPD, moderate tidal vol-
umes are generally desired. The higher aspect of the
estimated range (15 cc/kg) can potentially cause baro- IIB1b
trauma, whereas the lower end of the range (10 cc/kg) 16. C. Most disposable bubble humidifiers come equipped
might require a faster frequency and might not provide with a pressure pop–off valve (pressure release). This
for adequate expiratory time and cause air trapping. device sounds when the flow rate of oxygen into the
The CRT should attempt to establish a tidal volume humidifier is greater than the flow rate that is capable
somewhere about mid-range (e.g., 650 cc–750 cc). A of leaving the humidifier. The disparity between the
tidal volume of 700 cc (approximately 12.5 cc/kg) flow rate entering and the flow rate exiting can result
would probably be a good starting point. from too high of a setting on the flow meter. The out-
flow port cannot accommodate this flow rate; as a re-
When the patient’s height and sex are given, the fol-
sult, pressure builds within the humidifier, activating
lowing formulas can be used to determine the IBW:
the alarm as the excessive pressure is vented to the at-
(MEN) IBW (lbs) = 106 + mosphere. If the outflow port or tubing attached to the
[6 + (height in inches  60)] outflow port is occluded, pressure will build within the
humidifier, also activating the alarm. The alarm sounds
(WOMEN) IBW (lbs) = 105 +
at a pressure of greater than or equal to 2 psi.
[5 + (height in inches  60)]
The efficiency of a bubble humidifier is affected by (1)
Once the IBW is known, the guideline of 10–15 cc/kg
the time of contact available between the gas and wa-
of IBW can be better applied (of course, only after the
ter, (2) the gas bubble’s surface area-to-volume ratio,
IBW in lbs is divided by 2.2 lbs/kg).
and (3) the temperature of the gas. A drop in the water
(1:896–897), (10:207–208), (15:951–952). level will decrease the amount of time available for
gas-water contact. This situation will not activate the
IIIC1e alarm, however. Similarly, an increase in the oxygen’s
14. A. Total gas flow into small oxyhoods should exceed 7 flow rate through the humidifier will decrease the
L/min. to prevent carbon dioxide buildup within the amount of time for the diffusion of water vapor into
hood. Flows of 10–12 L/min. are recommended for the gas bubble. Finally, smaller bubbles will improve
large hoods and hut (Cam) tents. Flows are adjusted to the ratio of gas-bubble surface area to gas-bubble vol-
achieve the prescribed FIO2 (which should be continu- ume and, consequently, the efficiency of humidifica-
ously monitored) and the desired PaO2 range of 50–60 tion. Simple bubble humidifiers can provide a relative
torr. Flow rates greater than 15 L/min. are generally humidity of approximately 40% when operating at
unnecessary and might produce harmful noise levels. maximum efficiency.

(1:760), (2:359), (5:75–76), (18:68). (1:663–664), (5:99–102), (16:434), (18:91–93).

IIID9 ID1d
15. B. The minimal leak technique enables the CRT to ap- 17. C. Although this patient seems to be recovering and
ply enough air to the ET tube cuff to seal the airway appears likely to be weaned soon from mechanical
for ventilation and still apply as little pressure on the ventilation and extubated, lowering the PEEP to a rea-
tracheal wall as possible. During positive-pressure in- sonable level, usually 5 cm H2O or less, must be done
spiration, a controlled leak around the cuff is allowed first. The PaO2 indicates that either the PEEP or the
to occur near the end of inspiration to minimize the FIO2 can be decreased. Because the FIO2 is already
pressure against the tracheal wall. Upon exhalation, down to 0.40, however, decreasing the FIO2 further is
when the airways shorten and narrow, a more complete unnecessary for weaning this patient from mechanical
seal develops between the cuff and the trachea. ventilation. Therefore, attention should be directed to-

410 Chapter 6: Posttest

 ward lowering the PEEP. Further decreases in the ven- liver breaths to a patient, he should immediately dis-
tilatory rate would likely be well tolerated, but a pa- connect the patient from the ventilator and ventilate
tient can be extubated from a ventilatory rate of 6 the patient with a manual resuscitator until the prob-
breaths/min. if all other settings and measurements in- lem can be corrected.
dicate that the patient is ready for discontinuance of
(1:907–908).
mechanical ventilation.
(1:971–974), (10:284, 325), (15:891–917). IIIC2c
21. B. Possible adverse reactions during suctioning should
IIIE1i(1) be anticipated. Appropriate preparation and monitor-
18. B. The formula for calculating the pressure-support ing of the patient before, during, and after suctioning is
level (PPS)is as follows: essential to minimize the risk of any adverse reactions
that might occur. Pre- and post-oxygenation of the pa-
(peak inspiratory
) (
static
 pressure ) patient peak tient with 100% oxygen is a standard protocol used to
PPS =
pressure
mechanical peak
inspiratory flow rate
(
 inspiratory
flow rate
) avoid causing hypoxemia. While in the airway, the
suction catheter reduces the lumen of the airway, and
the vacuum applied reduces the amount of oxygen and
STEP 1: Convert both the mechanical and patient volume in the lungs. If a patient experiences a sudden,
peak inspiratory flow rates from L/min. to significant oxygen desaturation, immediate with-
L/sec. drawal of the catheter from the airway is imperative to
administer 100% oxygen to the patient.
A. mechanical peak inspiratory flow rate:
(1:616–620). (“AARC Clinical Practice Guidelines.
80 L/min. Endotracheal Suctioning of Mechanically Ventilated
= 1.333 L/sec.
60 sec./min. Adults and Children with Artificial Airways,” 1993,
Respiratory Care, 38, pp. 500–504).
B. patient peak inspiratory flow rate:
40 L/min. IIA2
= 0.667 L/sec.
60 sec./min. 22. D. Recyclable equipment, such as reservoirs, tubing,
nebulizers, valves, etc., is classified as semi-critical
STEP 2: Calculate the pressure-support level. items. Semi-critical items must ultimately be steril-
50 cm H2O  30 cm H2O ized. Before being sterilized, semi-critical items must
PPS = ( 1.333 L/sec. ) (0.667 L/sec.) be processed with low- or intermediate-level disinfec-
tion before being subjected to the sterilization process.
Semi-critical items that are heat-sensitive can be ster-
= (
20 cm H2O
1.333 ) (0.667) ilized with ethylene oxide, and those that are heat sta-
ble can be sterilized in a steam autoclave.
= (15 cm H2O)(0.667) (1:51–52).
= 10 cm H2O
IB1b
(1:980).
23. D. The I:E ratio, inspiratory time (TI), and ventilatory
rate controls on some ventilators are dependent vari-
IB4c
ables; that is, after two are set, the third becomes es-
19. A. The systolic blood pressure indicates the force gen- tablished. The ventilatory rate establishes the total
erated during contraction of the left ventricle. The di- cycle time (TCT) according to the following formula:
astolic pressure is the force developed when the left
ventricle is relaxed (diastole). The combination of
60 sec./min.
these two pressures comprises the peripheral arterial TCT =
blood pressure, as indicated by the use of the sphyg- ventilatory rate (breaths/min.)
momanometer and a stethoscope.
(1:183–184, 304–305), (9:43–45). The following formula can be used to calculate the I:E
ratio:
IIB1e(1)
TI TCT  TI
20. D. If a CRT is unable to rapidly determine the cause of I:E = :
ventilator malfunction for any reason, especially to de- TI TE

Chapter 6: Posttest 411

 where, 60 sec./min.
TCT =
TCT = total cycle time (sec.) 24 breaths/min.
TI = inspiratory time (sec.)
= 2.5 sec.
TCT  TI = expiratory time or TE (sec.)
TI TI
For example, the Bear BP-200 has controls for all three =
variables: (1) inspiratory time, (2) ventilatory rate, and TI + TE TCT
(3) I:E ratio. Because these controls are not independent
1 TI
variables, however, only two of the controls are working =
at any particular time. The ventilatory rate control is al- 1+2 2.5 sec.
ways working, and the BP-200 is designed so that either
1 TI
the maximum inspiratory time control or the I:E ratio =
control will establish the TI and the I:E ratio. The control 3 2.5 sec.
that establishes the shortest TI is the one that is in effect.
2.5 sec.
If the maximum inspiratory time control is the control- TI =
ling factor, a red indicator light will illuminate each time 3
the ventilator cycles into inspiration.
= 0.83 sec.
The first step in solving the problem is to see which
In this case, the I:E ratio, which is set at 1:2, would
combination of controls would provide the shortest TI.
render the shortest TI.
I. TI 1.0 sec.; ventilatory rate 20 breaths/min.;
III. TCT 2.5 sec.; TI 0.83 sec.
I:E 1:1
(same calculations as II)
60 sec./min.
TCT = In this case, the maximum inspiratory time control
20 breaths/min. would establish the I:E ratio. The calculation is as fol-
lows:
= 3 sec.
TI TCT  TI
The I:E ratio can be used to calculate inspiratory time I:E = :
as a fraction of the total cycle time. TI TI
TI TI 0.6 sec. 2.5 sec.  0.6 sec.
= = :
TI + TE TCT 0.6 sec. 0.6 sec.
1 TI = 1:3.2
=
1+1 3 sec. IV.TI 0.5 sec. ventilatory rate 40 breaths/min.;
I:E 1:1.5
3 sec.
TI = 60 sec./min.
2 TCT =
40 breaths/min.
= 1.5 sec.
= 1.5 sec.
Because the I:E ratio control would establish a longer
inspiratory time, the maximum inspiratory time con- I TI
trol would establish TI. The I:E ratio is calculated as =
I +E TCT
follows:
1 TI
TI TCT  TI =
I:E = : 1 + 1.5 1.5 sec.
TI TI
1.5 sec.
1 31 TI =
= : 2.5 sec.
1 1
= 0.6 sec.
= 1:2
Once again, the maximum inspiratory control would
Similar calculations should be made for the other com-
establish the I:E ratio as calculated:
binations presented in the problem.
TI TCT  TI
II.TI 1.0 sec.; ventilatory rate 24 breaths/min.; I:E = :
I:E 1:2 TI TI

412 Chapter 6: Posttest

 0.5 sec. 1.5 sec.  0.5 sec. = 600 breaths/min.
= :
0.5 sec. 0.5 sec. 40
= 1:2 = 15 breaths/min.
(1:860), (10:205–206).
Therefore, to achieve an arterial PCO2 of 40 torr, the
CRT must change (increase) the ventilatory rate to 15
IIIC1d breaths/min. Because the anatomic dead space does
24. A. This patient is already receiving a tidal volume of not change significantly from breath to breath, the fol-
14.5 cc/kg of IBW (800 cc ÷ 55 kg). Increasing the lowing equation can be used:
tidal volume to 900 cc would exceed the upper limit of
an acceptable tidal volume, based on 15 cc/kg of IBW. (known PaCO2)(known f)(known VT)
desired f =
The ventilator setting to alter in this situation is the ven- (desired PaCO2)(known VT)
tilatory rate. The effect of increasing the ventilatory rate When the tidal volume does not change, the tidal vol-
would be to increase the minute ventilation (i.e., f  VT ume can be omitted from the equation—because it oc-
= V̇E). Specifically, the alveolar ventilation is what needs curs in both the numerator and denominator.
to be increased (i.e., V̇A = V̇E  V̇D). The degree to which
the ventilatory rate needs to be adjusted can be somewhat (15:994–995).
empirally determined by applying the following formula:
IIIF1
25. C. Encountering elderly, edentulous patients who re-
Known Values Desired Values
quire bag-mask ventilation is not uncommon. These
(PaCO2)(f)(VA) = (PaCO2)(f)(VA) patients pose a challenge to a CRT’s manual dexterity
and ability to ventilate under duress.
Substituting the factor VT  VD for VA, the equation is To overcome the problem of maintaining an adequate
as follows: seal with the mask against the face in this situation, the
CRT should pull the patient’s cheeks up over both
sides (lateral aspects) of the face. To accomplish this
Known Values Desired Values
maneuver, the CRT will need to position her thumbs
PaCO2(f)(VT  VD) = (PaCO2)(f)(VT  VD) on the top of the mask and, using her fingers, raise the
patient’s cheeks to meet the edges of the mask. An ad-
equate seal will likely be created. This situation now
To obtain an estimate for the anatomic dead space, use requires a second person to perform the manual venti-
the guideline indicating that each pound (lb) of IBW is lation, because the CRT has both hands occupied.
equivalent to 1 cc of anatomic dead space. Therefore,
because this patient has an IBW of 120 lbs, she has ap- (1:650), (15:826), (16:565).
proximately 120 cc of anatomic dead space (VD).
IIIB2a
Her alveolar volume can be calculated as follows:
26. D. For postural drainage to be accomplished effec-
VA = VT  VD tively, the patient must be positioned in such a manner
= 800 cc  120 cc as to employ the use of gravity to assist in the move-
ment of secretions from a specific region of the lungs.
= 680 cc Essentially, the lung segment involved or targeted for
drainage must be placed 90º horizontally.
The given and derived values can now be inserted into
the formula used to determine the desired ventilatory In this situation, the superior basal segments of both
rate (desired f). This expression now becomes: lungs require drainage. Therefore, placing the patient
on his abdomen with his body in a flat horizontal po-
sition (flat prone) will result in gravity assisting in the
Known Values Desired Values drainage of these lung segments.
(60 torr)(10 bpm)(680 cc) = (40 torr)(f)(680 cc) (1:798–801), (2:439–441).

(60 torr)(10 bpm)(680 cc) IIB1a(3)

desired f = 27. B. The Yankauer suction device is used for oropharyn-
(40 torr)(680 cc) geal suctioning. When a patient has an artificial airway

Chapter 6: Posttest 413

 inserted, oropharyngeal secretions sometimes accu- IIIB2b
mulate above the tube’s cuff. The Yankauer suction de- 31. A. Suctioning this patient would eliminate the alarm
vice is effective in removing these secretions, situation. The accumulation of secretions in the airway
especially if they are thick. The Yankauer suction de- would produce an increase in the airway pressures,
vice is generally operated at negative pressures rang- causing the pressure in the system to reach the high-
ing from –100 to –120 mm Hg, which is the same pressure limit. The high-pressure limit control con-
suction-pressure range recommended for ET suction- fines the amount of pressure being delivered to the
ing of adults. If secretions are extremely viscous and patient. Sedation in this situation is not warranted. This
copious, or if vomitus is present in the oropharynx, a patient was receiving an inadequate tidal volume be-
greater negative pressure can be used. Therefore, in the cause the ventilator prematurely cycled into the expi-
situation posed here, the CRT should inform the nurse ratory phase. Sedation would have been detrimental to
to use a more negative suction pressure (i.e., –100 to this patient.
–120 mm Hg).
(1:853–854), (10:229, 311–312).
(1:616), (2:430).
IIB1j(1)
IIIC2a 32. C. The PIP will increase whenever more pressure
28. D. The patient’s exhaled gas cannot be sufficiently needs to be generated to deliver the tidal volume to the
flushed from a demand-flow CPAP system if the pa- patient. Many factors influence the PIP. Among the
tient’s tidal volume falls below the system’s critical factors responsible for an increased PIP are the accu-
volume. If such a situation develops, the patient will mulation of condensate in the tubing and kinks in the
rebreathe his own expirate and develop carbon dioxide ventilator circuitry. Both of these developments in-
retention. crease the airway resistance through the ventilator cir-
(1:865–866), (2:450–451, 554), (10:281–282), cuit. Therefore, either of these situations would be
(15:915–916). associated with an increased PIP.
An increase in the tubing compliance means that the
IIB2d ventilator circuitry is more compliant (i.e., more easily
distended). Ordinarily, the compliance of the ventilator
29. A. Studies have consistently shown that for one per-
circuit is constant at around 3 ml/cm H2O, which
son, mouth-to-mask ventilation provides larger tidal
means that for each centimeter of H2O pressure devel-
volumes than bag-mask ventilation. Demand valves
oped in the system to deliver the tidal volume to the
are generally not recommended because of their many
patient, 3 ml of volume is compressed in the tubing.
drawbacks, including (especially in older models) high
For example, if a PIP of 35 cm H2O was generated, the
flow rates and their lack of an audible signal when the
volume compressed in the tubing would be 105 ml
maximum pressure is reached. Whenever possible, a
(i.e., 35 cm H2O  3 ml/cm H2O).
professional rescuer should avoid performing mouth-
to-mouth ventilation (except, of course, on family Excessive heat production in the ventilator tubing, per-
members). haps by a faulty heated-wire circuit or too high a hu-
midifier temperature setting, can result in an increase
(“Guidelines for Cardiopulmonary Resuscitation
in tubing compliance.
and Emergency Cardiac Care,” 1992, Journal of
the American Medical Association, 268(16), (10:254, 311).
pp. 2199–2200), (1:632–650).
IB1a
IIIB2c 33. B. Cachexia refers to general ill health and malnutri-
30. A. The optimum position for a small-volume nebulizer tion associated with serious disease. Many patients
used in conjunction with a mechanical ventilator is on with AIDS will develop a wasting syndrome, leading
the inspiratory limb at least 18 inches before the Y to an emaciated, cachectic appearance.
adaptor. Placing the nebulizer at the Y adaptor results (9:39), (15:771).
in too much turbulence at the opening of the ET tube
(and therefore, less inhaled medication). IIID5
(15:809–810), [Hughes, J., and Saez, J., “Effects of 34. D. The rationale for continuously monitoring and as-
Nebulizer Mode and Position in a Mechanical Venti- sessing a patient’s cardiac rhythm include (1) deter-
lator Circuit on Dose Efficiency,” 1987, Respiratory mining the patient’s need for continued care, (2) noting
Care, 32(12), pp. 1131–1135]. the patient’s response to therapy or medications, and

414 Chapter 6: Posttest

 (3) observing any sudden changes in the cardiac rate ratory time. The outcome is often improved oxygenation
and rhythm. Monitoring a patient’s cardiac status will because of the increased mean airway pressure. Other
enable the CRT to detect a dysrhythmia as soon as it clinical conditions (COPD and asthma) do not conform
develops. Treatment of life-threatening dysrhythmias to the use of inversed I:E ratios, because these diseases
will result in the least amount of damage to the heart are associated with increased ventilation time constants.
muscle when treated as soon after the onset as possi- Therefore, longer expiratory times are required.
ble. Most sudden deaths of cardiac origin occur as a re-
The CRT must also safeguard against the development
sult of electrophysiologic interruption of the heart. The
of auto-PEEP in mechanically ventilated COPD and
cardiac monitor will allow for rapid detection of any
asthmatic patients. I:E ratios or 1:3 or 1:4 might be
such interruptions.
needed for these patients who have increased ventila-
(1:907), (10:248). tion time constants. The ventilation time constant is
the mathematical product of the patient’s pulmonary
IIB1a(1) compliance and airway resistance.
35. D. The flow to a nonrebreathing mask must be ad- Ventilation time constant =
justed so that the bag does not collapse completely (lung compliance)(airway resistance)
during inspiration. Although the suggested minimum
V liter P cm H2O
flow rates vary, at least 6 L/min. are needed to com-
pletely flush out the patient’s exhaled carbon dioxide
from the mask between breaths. Despite that this pa-
(sec.) = ( P cm H2O )( V̇ L/sec. )
tient has COPD, only a small percentage of COPD pa- where,
tients are actually CO2 retainers. Additionally, hypoxia
is a worse problem. If hypoventilation develops, it can  = (tau) ventilation time constant (sec)
be treated by positive-pressure ventilation. V/P = lung compliance (L/cm H2O)
P/V = airway resistance (cm H2O/L/sec.)
(1:749–751), (13:64–65), (16:387–388).
(1:859, 887), (10:145, 205, 211),
(17:22–25, 58, 320–324).
IIIA2b(1)
36. D. The auditory (eustachian) tube opening into the na-
sopharynx is sometimes blocked by the presence of a IIB1k
nasotracheal tube. Otitis media (middle-ear infection) 38. A. An obstructed capillary tube will prevent entrainment
can result from this blockage. Sinus drainage is some- of medication. An obstructed jet will prevent gas flow
times blocked as well, leading to acute sinusitis. Tra- that is essential for nebulization. Although a broken baf-
cheitis is a late complication of a tracheotomy. fle would hinder the operation of the nebulizer, an aerosol
Epiglottitis is not a complication of any form of tra- would still be produced. Particle size would be larger,
cheal intubation; in fact, it is often an indication. with a greater disparity of size. Inadequate inspiratory
(1:593), (2:423). pressure would not cause elimination of the aerosol.
(1:778–783).
IIID7
37. A. In a spontaneously breathing person, the I:E ratio is
normally 1:2 to 1:4. During positive-pressure mechani- IIIF2
cal ventilation, similar I:E ratios are sought primarily to 39. D. Defibrillation is the application of an asynchronized
reduce the associated adverse cardiovascular effects. electrical shock to the myocardium, attempting to
The mean intrathoracic pressure increases during the in- achieve simultaneous myocardial depolarization. De-
spiratory phase of positive-pressure ventilation and de- fibrillation is applied to patients who exhibit ventricu-
creases during exhalation. When inspiratory time lar fibrillation and pulseless ventricular tachycardia.
exceeds expiratory time, the mean intrathoracic pressure Although similar to defibrillation, cardioversion in-
increases. This positive-pressure effect tends to cause a volves the application of an electrical shock to a pa-
decreased venous return and a decreased C.O. There- tient’s myocardium in synchrony with the R wave on an
fore, higher (reversed) I:E ratios tend to more adversely ECG tracing. The purpose of applying the electrical
influence the C.O. shock in synchrony with the R wave is to avoid having
Certain clinical situations sometimes respond favorably the myocardium stimulated during the heart’s refractory
to increased or reversed I:E ratios. For example, ARDS, period, thus avoiding ventricular fibrillation or pulseless
which is characterized by a decreased lung compliance, ventricular tachycardia. Furthermore, cardioversion re-
is often treated with an inspiratory time exceeding expi- quires less electrical energy than defibrillation.

Chapter 6: Posttest 415

 Cardioversion is applied to patients who have the fol- creasing intracuff pressure. Either a mercury column
lowing dysrhythmias: or an aneroid manometer is acceptable. Overinflating
the cuff in anticipation of volume loss is potentially
Dysrhythmias Treated with Cardioversion
dangerous. Any additional volume in excess of the
minimum occluding volume (MOV) is contraindicated
• supraventricular tachycardia and might lead to tracheal damage.
• atrial flutter (1:609–610), (10:255–256), (16:575–577).
• atrial fibrillation
• ventricular tachycardia
IIIE3
(1:653, 657), (American Heart Association, Advanced 43. A. Acetylcysteine is a mucolytic that disrupts the
Cardiac Life Support, 1994, pp. 1-35, 4-1, 4-6, and 4-7). disulfide bonds in mucoproteins, thus decreasing the
viscosity of mucus. Guaifenesin is an expectorant that
IIIC2a stimulates bronchial mucus glands. Cromolyn sodium
is used to prophylatically prevent bronchospasm.
40. A. Therapeutically, PEEP often has the effect of in- Ethyl alcohol destabilizes the exudative froth of pul-
creasing the FRC, reducing the alveolar arterial oxy- monary edema.
gen tension difference and preventing atelectasis by
keeping the lungs hyperinflated during exhalation. (8:165–167, 178–179, 214–219, 271), (15:188–189),
PEEP is known to impede venous return, decrease (16:472, 475, 476, 477–478, 488).
C.O., and increase intracranial pressure.
IIIE1i(1)
The application of PEEP also elevates the mean airway
pressure (P̄aw). The P̄aw elevation is generally associated 44. A. A patient who experiences a respiratory acidosis
with an increased arterial PO2. If PEEP is increased while receiving mechanical ventilation is being hy-
beyond its optimum level, the pulmonary compliance poventilated. If this situation occurs while he receives
and the arterial PO2 will decrease. ventilatory support via a time-cycled ventilator, in-
creasing the inspiratory time will increase the tidal vol-
(1:880, 912, 914), (2:535–546), (15:724, 727–728). ume and will help eliminate more carbon dioxide. To
correct this problem when a volume-cycled ventilator
IB4a is being used, the tidal volume should be increased to
41. A. Auscultation of the chest can assist the CRT with 15 cc/kg of IBW. If the tidal volume is already at that
diagnosing either the presence of increased, absent, level, the ventilatory rate should be increased. If a res-
decreased, or unequal breath sounds. Poor transmis- piratory acidosis develops while a patient receives
sion of breath sounds suggests an abnormality within pressure-cycled or flow-cycled ventilation, increasing
the lungs. The absence of breath sounds can indicate the cycling pressure becomes the corrective measure.
the occurrence of a pneumothorax or a tumor. The tu- (1:936–937), (2:527–528), (10:251).
mor (benign or malignant) can be threatening to the
lung, but not detrimental to the life of the patient.
IIB1a(1)
Every tumor is not malignant. Auscultation of the
chest should be performed frequently to note changes 45. B. Generally, nonheated humidifiers come equipped
in the patient’s condition. with a pressure pop-off valve set to release at 2 psi. In-
tentionally kinking or pinching closed the oxygen tubing
(1:310–314), (9:62–66), (16:171–174). to generate pressure in the system is standard practice af-
ter setting up a cannula or a simple mask. This practice
IIB1f must not be done while the oxygen-delivery device is at-
42. D. Commercially designed cuff manometers have tached to the patient, however. This practice enables
short connecting tubes to prevent volume loss during the CRT to determine the proper functioning of the
connection. The system described will work well if the pop-off valve and to evaluate the oxygen-delivery sys-
oxygen-connecting tube is shortened. Prepressurizing tem for leaks.
the manometer by adding volume to increase manome- If there are no leaks, the pop-off valve will sound. If no
ter pressure to previous pressure readings before con- sound is heard, the system should be checked for
nection will also prevent pressure loss. Caution must leaks, and the safety relief valve should be inspected
be exercised to prevent adding excessive pressure, be- for malfunctions.
cause too much pressure will ultimately cause volume
to flow to the cuff when the stopcock is opened, in- (1:664), (5:101), (13:93).

416 Chapter 6: Posttest

IIIA3 Patients who have neuromuscular disease (e.g., Guil-
46. D. The Centers for Disease Control and Prevention lain-Barré and myasthenia gravis) can deteriorate
(CDC) has recommended a policy known as “universal rapidly and slip into acute ventilatory failure if their
precautions,” based on the fact that patients might be ventilatory status is not monitored.
unknowingly infected with hepatitis B or the Human Vital capacity (VC), maximum inspiratory pressure
Immunodeficiency Virus (HIV). This policy states that (MIP), maximum expiratory pressure (MEP), and tidal
gloves and other barriers must be used to reduce the volume (VT) measurements reflect the patient’s di-
risk of parenteral, mucous membrane, and nonintact aphragmatic status. The respiratory rate indicates the
skin exposures to blood and body fluids. The principle patient’s work of breathing.
is to assume that all patients are potentially infective,
regardless of their clinical condition. Generally, if a patient’s VC falls somewhere between 12
to 15 cc/kg and if the MIP is less than -20 cm H2O, the
(15:1133–1134). patient should be intubated and mechanically ventilated.
This patient’s VC is 10 cc/kg; i.e., 900 cc  87 kg.
IIIF2
(1:542–546), (16:1052–1053).
47. B. When tachycardia produces serious cardiovascular
signs and symptoms in a hemodynamically unstable
patient, cardioversion should be used before antidys-
rhythmic medications are administered. Furthermore, IIIF1
in these situations, a heart rate greater than 150 50. B. The most reliable indication that rescue breathing
beats/min. warrants immediate cardioversion. (i.e., mouth-to-mouth or bag-mask) is inflating the pa-
tient’s lungs is to observe the rise and fall of the victim’s
Immediate cardioversion is usually unnecessary for
chest. Chest excursions can only be the result of in-
heart rates that are less than 150 beats/minute.
creased lung volume. Although the resistance character-
(American Heart Association, Advanced Cardiac Life istics of the lungs as they expand are a useful indicator,
Support, 1994, pp. 1-32 to 1-35 and 4-3). they are not the most reliable. Inflation of the lungs can
still be achieved, even in the presence of increased resis-
IIIE1i(1) tance.
48. D. The ABG reveals respiratory alkalosis with hyperox- (1:632–635), (16:563–568).
emia. Because the patient is receiving assist-control
ventilation at a rate of 15 breaths/min., he is blowing off
too much CO2. Although the rapid ventilatory rate might
be caused by pain, anxiety, or some other factor, seda- IIIC1f
tion deep enough to abolish breathing is likely to pro- 51. A. Before deciding what action is appropriate, the
duce adverse cardiovascular effects. Changing the mode CRT should determine this patient’s IBW. The follow-
to IMV will enable the patient to breathe at his own rate ing formula should be used:
while making it easier to adjust the ventilator settings to
normalize the ABGs. Decreasing the machine’s ventila- (MEN) IBW (lbs) =
tory rate in the assist–control mode would not be help- 106 + [6  (height in inches  60)]
ful, because the patient is assisting. Decreasing the tidal (WOMEN) IBW (lbs) =
volume to a level less than 10 cc/kg is inadvisable, be- 105 + [5  (height in inches  60)]
cause it is likely to result in atelectasis.
(1:931–933), (10:250–252). This patient is male; therefore, the appropriate formula
for men should be used. His IBW in pounds will be:
IIIC1d
IBW (lbs) = 106 + [6  (70 inches  60)]
49. C. A patient’s ventilatory status can be evaluated by
obtaining the following physiologic measurements: = 106 + 60

Physiologic Measurements Evaluating

= 166 lbs
Ventilatory Status
Convert his IBW to kilograms:
• tidal volume
• respiratory rate 166 lbs
IBW (kg) =
• vital capacity 2.2 lbs/kg
• maximum inspiratory pressure
• maximum expiratory pressure = 75 kg

Chapter 6: Posttest 417

 Now that this patient’s IBW is known, the CRT can Known Values Desired Values
evaluate the appropriateness of the patient’s tidal vol-
ume setting. The tidal volume is 850 cc, which falls (47 torr)(12 bpm)(684 cc) = (70 torr)(f)(684 cc)
within the 10–15 cc/kg (IBW) guideline:
850 cc (47 torr)(12 breaths/min.)(684 cc)
= 11.33 cc/kg desired f =
75 kg (70 torr)(684 cc)
Based on this information, it is clear that the tidal vol- (47)(12 breaths/min.)
ume is not large and is not contributing to this patient’s =
70
hyperventilation. The SIMV rate appears a bit high
at 12 breaths/min. This patient’s mechanical minute = 8 breaths/min.
ventilation is 10.2 L/min. (12 breaths/min.  0.85
The SIMV rate should be reduced to approximately 8
L/breath). The patient might also be breathing sponta-
breaths/min. to raise the arterial PCO2 to around 70
neously. Therefore, his minute ventilation should be
torr. This patient’s oxygenation status appears to be ad-
reduced. Because the patient is being overventilated,
equate. From a practical standpoint, however, the
he is likely not breathing spontaneously.
equation used can be as follows:
The purpose of attempting to lower this patient’s
minute ventilation is to restore the ABG and acid-base (known PaCO2)(known f)
statuses to their normal levels. For example, the arter- desired f =
(desired PaCO2)
ial PCO2 of 47 torr is quite low. This patient’s PaCO2
should probably be somewhere around 65–70 torr, The decision has been made to not change the tidal
considering the HCO 3̄ level (37 mEq/liter). With a volume.
PaCO2 within the 65–70 torr range, the pH should be
(2:291–293), (10:250–254), (15:951–952), (17:35–38).
between 7.34 and 7.37. Therefore, to get the arterial
PCO2 higher, the SIMV rate should be decreased. The
level to which the SIMV rate should be reduced is IIIG2a
based on the following relationship: 52. B. Exercise is an essential element of a pulmonary-
rehabilitation program. Within the exercise prescrip-
tion, a target heart rate is established. The target heart
Known Values Desired Values
rate is based on the results of the rehabilitation pa-
(PaCO2)(f)(VA) = (PaCO2)(f)(VA) tient’s initial exercise assessment. A formula called
Karvonen’s formula is used to calculate the target heart
rate based on knowing the patient’s peak heart rate and
Substituting the factor VT  VD for VA, the equation resting heart rate. A factor of 0.6 is also included in the
becomes: equation, which is shown as follows:
THR = [(PHR  RHR) 0.6)] + RHR
Known Values Desired Values
where,
(PaCO2)(f)(VT  VD) = (PaCO2)(f)(VT  VD)
THR = target heart rate (beats/min.)
PHR = peak heart rate (beats/min.)
To obtain an estimate of the anatomic dead space, use RHR = resting heart rate (beats/min.)
the guideline of 1 cc of anatomic dead space per pound
In this problem, the patient’s PHR was 135 beats/min.,
of IBW. Therefore, because this patient has an IBW of
and the RHR was 80 beats/min. Therefore,
166 lbs, she has approximately 166 cc of anatomic
dead space (VD). Her alveolar volume can be calcu- THR = [(135 beats/min.  80 beats/min.) 0.6]
lated as follows: + 80 beats/min.
VA = VT  VD = [(55 beats/min.) 0.6] + 80 beats/min.
= 850 cc  166 cc = 33 beats/min. + 80 beats/min.
= 684 cc = 113 beats/min.
The given and derived values can now be inserted into A Borg scale from 0 to 10 is sometimes used for pa-
the formula that is used to determine the desired ven- tients who are severely impaired and who have a THR
tilatory rate (desired f). This expression now becomes as an unreliable index of the level of work they per-
the following: form. The Borg scale is also used for patients who can-

418 Chapter 6: Posttest

 not monitor their heart rate. The scale is based on the resuscitator that meets patient needs and safety.
patient’s perception of dyspnea or exertion. A score of
(1:619, 645–647), (5:235), (13:147–148).
4 to 8 within the 0 to 10 scale is a realistic goal.
(1:1094), (16:883). IIIA1
56. B. Explaining the planned therapy and desired goals to
IIA1b the patient in understandable terms helps reduce anxi-
53. D. To provide humidity to the airway at body temper- ety and achieve the best therapeutic outcome. Using
ature, the humidifier must be heated. One hundred per- language that the lay person will understand is impor-
cent relative humidity (R.H.) at room temperature tant. For example, medical terminology unfamiliar to
(21ºC) is approximately equivalent to an absolute hu- the patient is inappropriate (e.g., “The treatment pre-
midity (A.H.) of 18 mg/liter. When air is heated to vents postoperative atelectasis and helps you mobilize
body temperature, air is capable of holding 44 mg/liter retained secretions through a sustained maximal inspi-
of water. Therefore, a humidity deficit of 26 mg/liter ration”). Also important is avoiding making promises
(44 mg/liter18 mg/liter) will exist, providing a or suggesting problems that might or might not occur.
%R.H. of only 40%. Although a jet humidifier is more Encourage the patient to breathe deeply to help prevent
efficient than a bubble humidifier, it cannot produce lung complications after the operation. This direction
the desired results. clearly states what incentive spirometry is and what it
can accomplish in a manner that will encourage the pa-
Condensing humidifiers, also referred to as heat-
tient without confusing her or making her fearful.
moisture exchangers (HMEs) or artificial noses, fall
short of the capability of the human nose. Studies in- (AARC Clinical Practice Guidelines for Incentive
dicate that most HMEs are capable of providing be- Spirometry).
tween 22 and 28 mg/liter of water to the airway, or
between 50% and 65% body humidity. IIIE1j
The heated cascade humidifier is the second-best 57. B. The subject of weaning patients from mechanical
choice listed. Although this device is capable of pro- ventilation evokes lively debate among clinicians, be-
viding humidity at body temperature, it cannot do so at cause numerous methods of weaning exist. All have
the high-system flows (60–90 L/min.) necessary for a varying degrees of success, depending on the clinical
CPAP system. situation.
(1:665), (5:110–111), (13:96–97), (16:428, 437).
Weaning Methods
IIID5
54. A. The general goal of oxygen therapy is to maintain • T-piece or Briggs adaptor
adequate tissue oxygenation with the minimal expendi- • IMV
ture of cardiopulmonary work. Clinically, the achieve- • SIMV
ment of this goal (i.e., a positive response to oxygen • PSV
• CPAP with PSV
administration) should be associated with a stabiliza-
tion of vital signs. The stabilization of vital signs refers
to a normalization of the heart rate, blood pressure, and The patient in this question failed to wean because of
ventilatory rate and a decrease in the work of breathing. an inability to sustain spontaneous breathing. There-
The ability to maintain stable mechanical and physio- fore, choices including a Briggs adaptor (T-piece) and
logic values while lowering the FIO2 would also indi- CPAP would be unacceptable responses, because both
cate a positive response to therapy. of these ventilatory methods rely heavily on a patient’s
ability to sustain spontaneous breathing. The stem im-
(AARC Clinical Practic Guidelines for Oxygen Ther-
plies that both of these choices would fail, again be-
apy in the Acute Care Hospital), (1:738).
cause of the heavy reliance on spontaneous breathing.
IIA1d Volume-controlled ventilation with continuous manda-
55. A. A manual resuscitator is used in the clinical setting tory ventilation (VC-CMV) provides the patient’s en-
for more than rescue breathing. It is often used to pro- tire minute ventilation as mandatory breaths. The tidal
vide hyperinflation with 100% oxygen, or a controlled volume in every breath will be virtually equal. This
FIO2, before and after suctioning—as well as for trans- ventilatory method does not afford the patient many
porting critically ill patients in the hospital. All of the opportunities to assume much of the work of breathing
choices are positive features of a multiple-use manual and actually does not constitute a weaning method.

Chapter 6: Posttest 419

 Pressure-support ventilation (PSV) is conceptually re- IIIE1f
lated to IPPB and is a mode during which the patient 60. D. The administration of bland aerosol via an ultra-
breathes spontaneously. The breath is patient-triggered, sonic nebulizer (USN) can induce bronchospasm, par-
pressure-limited, and flow-cycled. Each breath is sup- ticularly in asthmatic patients. Bronchodilators should
plemented with a preset pressure. Low levels of PSV be administered before the treatment to prevent bron-
(i.e., 5 cm H2O) can eliminate the work of breathing chospasm. If a complication were to occur, the CRT
imposed by the endotracheal or tracheostomy tube should stop the treatment, notify appropriate individu-
and/or by the ventilator tubing. Greater levels of pres- als (such as the nurse and physician), and get further
sure support can eliminate the work of breathing im- instructions.
posed on the muscles of ventilation to perform
ventilatory work. Ultimately, even higher levels of (AARC Clinical Practice Guidelines for Bland
pressure support can remove all the work of breathing; Aerosol Administration), (1:673), (13:90).
i.e., the ventilator assumes the entire work of breathing.
In the PSV mode, the patient controls the respiratory IIIE1i(1)
rate, inspiratory time, and flow. The tidal volume is a 61. C. Controlled mandatory ventilation is time-triggered,
consequence of the preset pressure level, the patient’s continuous mandatory ventilation. The mandatory
effort, and the mechanical factors opposing ventilation. breaths are delivered to the patient at a preset time in-
When used for weaning from mechanical ventilation, terval. Controlled ventilation can be either volume-
PSV can gradually enable the muscles of ventilation to targeted or pressure-targeted. All the breaths can be
perform more of the work of breathing; that is, en- either volume controlled, pressure controlled, flow
abling the patient to incrementally assume more of the controlled, or time controlled. All breaths are manda-
work to breathe spontaneously. tory; the patient does not trigger inspiration.

The patient in this problem has had difficulty breathing Lowering the inspiratory flow rate during controlled
spontaneously for extended periods. The PSV mode mandatory ventilation has the following effects on the
would gradually and progressively remove the ventila- patient’s ventilatory status:
tor’s role in breathing for the patient. Eventually, the • increases inspiratory time (TI)
patient would be responsible for handling more and • shortens expiratory time (TE)
more of the imposed work of breathing. • increases the I:E ratio
(1:864, 874, 877), (15:279), (16:616, 632). • lowers the peak inspiratory pressure (PIP)
Controlled, continuous mandatory ventilation is used
IIIE1i(1) when a patient cannot initiate spontaneous breaths.
Examples include drug-overdose patients, central ner-
58. D. Adding 4 cm H2O will elevate the ventilatory base-
vous system malfunction or injury, respiratory failure,
line above ambient pressure, thus increasing the mean
and heavy sedation (i.e., when Pavulon is used).
intrathoracic pressure throughout the entire ventila-
tory cycle. Rather than starting each inspiration at 0 (1:858, 899), (5:361–362), (10:195–196), (16:661).
cm H2O, each inspiration will begin at 4 cm H2O. A
spontaneous pneumothorax would result in air being IIIE1i(1)
continuously deposited in the intrapleural space with 62. B. What has occurred in the course of the hour be-
each successive inspiration. The compression effect of tween the two sets of measurements (PIP and Pplateau) is
the intrapleural air would make ensuing volumes dif- the lungs became more stiff (i.e., the pulmonary com-
ficult to deliver. Marked elevations of PIP would be pliance decreased).
noted.
Peak inspiratory pressure and plateau pressure
(1:960), (15:1081–1082), (10:254). measurements.

Initial One Hour Later

IB4a
59. C. According to the American Thoracic Society, dis- PIP 30 cm H2O PIP 40 cm H2O
continuous bubbling or crackling sounds should be de- Pplateau 15 cm H2O Pplateau 25 cm H2O
scribed as crackles. The older term, rales, had been
used in the past to describe both continuous and dis-
continuous abnormal sounds. Crackles are associated The plateau pressure represents the pressure holding
with the movement of airway secretions or the sudden the lungs inflated during an inflation hold. The fact
popping open of small airways. that the Pplateau rose from 15 cm H2O to 25 cm H2O in-
dicates that the lungs became stiffer (decreased lung
(1:312–313), (9:64), (15:444–445). compliance). The PIP  Pplateau difference is 15 cm

420 Chapter 6: Posttest

 H2O in both cases, signifying that the airway resis- priate for all patients. If a particular weaning method is
tance has remained constant. not successful for a specific patient, another approach
should be attempted.
Pressure generated to overcome airway resistance.
(2:530–533).
Initial One Hour Later

30 cm H2O  15 cm H2O 40 cm H2O  25 cm H2O IB4a

= 15 cm H2O = 15 cm H2O 66. D. Normal breath sounds auscultated over the
parenchyma are called vesicular breath sounds. They
are soft, muffled, low-pitched sounds heard over the
During volume-controlled mechanical ventilation, a
peripheral lung areas. The sound is heard primarily
constant volume is delivered to the patient, despite
upon inspiration, with only a minimal expiratory com-
changes in compliance and airway resistance.
ponent.
(1:858, 896), (10:195–196, 256–259), (16:661–662).
(1:312–314), (2:254), (9:63–65).
IA1e
IIID4
63. A. Pneumonia is typically apparent on a chest radi-
67. C. This patient is experiencing alveolar hypoventilation
ograph as an area of consolidation or opacification.
along with hyperoxia. Generally, when a patient is ini-
ABG and spirometric abnormalities are nonspecific in
tially established on mechanical ventilation, the tidal
regard to underlying pathology. Thoracotomy is more
volume is set between 10–15 cc/kg of IBW. Another
likely to be reserved for lung biopsy to diagnose ma-
guideline states that if a mechanically ventilated patient
lignancy.
is being hypoventilated with a ventilatory rate of fewer
(1:429–430), (9:160, 170). than 8 breaths/min., the ventilatory rate should be in-
creased. If the ventilatory rate is greater than 8
IIB1h(5) breaths/min., however, the tidal volume needs to be in-
creased—assuming that it is not greater than 15 cc/kg.
64. B. Polarographic and galvanic fuel-cell oxygen analyz-
ers are adversely influenced by water vapor and high To correct for alveolar hypoventilation, increasing ei-
closed-system pressures. Therefore, the analyzer’s sen- ther the tidal volume or the ventilatory rate will cor-
sor probe must be placed in-line before the gas reaches rect the problem. Increasing the tidal volume must
the humidifier. Because humidification dilutes the gas receive preferential consideration, however. Increas-
sample, a lower-than-actual oxygen concentration will ing the tidal volume by 100 cc usually does not pro-
be obtained. Also, water will condense on the sensor, duce as great an increase in the mean intrathoracic
causing interference with the readings. Closed-system pressure as does raising the ventilatory rate one or two
pressures (i.e., PEEP and CPAP) cause false readings breaths/min. The CRT generally has a tidal volume
from these types of oxygen analyzers. range of 10–15 cc/kg within which to work. Excep-
tions to this range include COPD or asthmatic patients.
(2:455), (5:282–284), (13:185–186).
These patients ordinarily are ventilated at 8–10 cc/kg.
Regarding the patient in this problem, the patient
IIIC1h weighs 42 kg and is receiving a 500-cc tidal volume.
65. D. In patients with a flail chest, paradoxical chest-wall
The following calculation enables the CRT to deter-
movement sometimes reappears several hours following
mine where the initial tidal volume lies within the gen-
initial attempts to wean the patient from mechanical
erally acceptable range.
ventilation. The reappearance of paradoxical chest-wall
movement in conjunction with an increased ventilatory 500 cc
rate and accessory-muscle usage for breathing indicates = 12 cc/kg
42 kg
that the patient is not ready to be weaned from the ven-
tilator. A severe flail chest usually requires a minimum This patient is receiving a tidal volume of 12 cc/kg.
of five days of mechanical ventilation to enable ade- Therefore, the CRT can increase the patient’s tidal vol-
quate rib stabilization. Significant areas of flailing re- ume by 100 cc to 600 cc and still remain within the ac-
quire stabilization of the chest wall to enable both bone ceptable tidal volume range:
healing and prevention of atelectasis.
600 cc
Most patients can be weaned by any of the following = 14.3 cc/kg
42 kg
weaning techniques: T-piece trials, IMV, SIMV, pres-
sure-support ventilation, and combinations of the four. This setting change would be appropriate in this case.
A single, rigid approach to weaning will not be appro- ABG analysis would need to be obtained again in 15 to

Chapter 6: Posttest 421

 20 minutes to assess the effect of the tidal-volume ad- III2c
justment. Also, at this time the CRT should give con- 71. D. Patients who have unilateral lung disease might de-
sideration to lowering the FIO2, because an arterial velop hypoxemia while positioned with the diseased
PO2 of 150 torr is unnecessary. lung in a gravity-dependent position. The physiological
(1:896–899), (10:207–210), (15:994–995). cause of this phenomenon is attributed to dependent-po-
sitioned lung segments being on the steepest portion of
the volume-pressure or compliance curve; hence, more
IA2f
net ventilation and gas exchange takes place in this area.
68. B. Pulse oximetry conducted with a strip recorder of- If a patient who has left lower-lobe pneumonia is placed
fers a useful means of screening for nocturnal hy- on his right side (i.e., right lateral decubitus, or the
poventilation. A representative gradual decrease in “good lung” down), hypoxemia will be minimized.
saturation gives evidence of hypoventilation during
sleep. An older technique required placement of an ar- (10:297–298).
terial line for serial blood-gas measurements. Transcu-
taneous monitoring is not useful for this condition in IB1b
the adult population. Plethysmography is not indi- 72. B. Bronchiectasis is characterized by sputum that is
cated. copious, purulent, bloody, and foul smelling (fetid)
and that separates into three layers when allowed to
(9:361), (15:584–585).
stand in the sputum collection cup. Cystic fibrosis is
often complicated by bronchiectasis.
IIIC1b
(1:459–460), (9:26, 95).
69. C. During an IPPB treatment, the CRT must perform a
number of evaluation procedures in conjunction with ID1b
this mode of therapy. These evaluation procedures in-
clude: (1) bilateral auscultation of breath sounds, (2) 73. C. For moderate to severe cases of sleep apnea, most
noting sputum characteristics, (3) measuring the VT sleep clinicians recommend CPAP. CPAP effectively
(volume-oriented IPPB), (4) inspecting the chest wall eliminates obstructive or central apneas in nearly all pa-
for equal and bilateral chest expansion, (5) noting pa- tients who can tolerate it. CPAP has emerged as an al-
tient sensorium, and (6) observing the patient’s breath- ternative treatment for obstructive sleep apnea. When
ing pattern. administered through a nasal device, it distends the
oropharynx and prevents occlusion by the tongue and
(1:563), (15:845–847). soft palate. In other words, it acts as a “pneumatic
splint” and increases the patency of the upper airway
IIB1b during inspiration. More recently, CPAP also has been
70. D. The humidity deficit is defined as the amount of wa- successfully used in central sleep apnea disorders. Ex-
ter that must be rendered to the inspired air by the res- actly why CPAP should be effective in central disorders
piratory epithelium to raise the inspired air to 100% is not entirely understood. Recent research suggests
body humidity. In other words, the humidity deficit is that upper-airway collapse might also play a role in the
the difference between the absolute humidity at satu- induction of central sleep apnea. Specifically, central
ration at body temperature (capacity) and the actual sleep apnea might result, in part, from a reflex inhibi-
humidity of the inspired air (content). The equation for tion of ventilation caused by activation of the supra-
solving for the humidity deficit is as follows: glottic mucosal receptors during upper-airway closure.

humidity deficit = capacity  content The elimination of snoring is one of the criteria used
for determining the appropriate level of CPAP. The key
This expression can be rearranged to solve for the con- is to identify the minimum CPAP level effective in
tent. completely eliminating the sleep apnea and snoring.
content = capacity  humidity deficit After approximately one hour of sleep without CPAP,
the CPAP trial is initiated at 5 cm H2O, and the num-
= 44.0 mg/liter  15.7 mg/liter ber of apneic episodes is noted. If loud snoring or ob-
= 28.3 mg/liter structive apneic episodes are present after a 30-minute
trial, the CPAP is increased by 2.5 cm H2O increments.
The amount of water in the inspired air is 28.3 mg/ This process is repeated until both snoring and apnea
liter. are eliminated.
(1:89–91), (2:20–21), (17:41–42). (1:560–563), (9:360–361).

422 Chapter 6: Posttest

IIIE3 system, and pressure-support ventilation.
74. A. The most serious potential side effect associated A continuous-flow IMV system does not use a demand
with the use of Mucomyst (n-acetylcysteine) is bron- valve. A one-way valve, communicating the IMV sys-
chospasm. This complication is especially true for tem with the ventilatory circuitry, remains continu-
asthmatics. The threat of this side effect is present for ously open until the ventilator delivers the preset
any type of patient, however. mandatory breaths. Between the mandatory breaths,
In the case presented, the COPD patient being treated the patient receives the benefit of a continuous flow of
with Mucomyst is likely experiencing the onset of a gas as spontaneous breathing occurs.
bronchospasm. Therefore, adding a bronchodilator Decreasing the SIMV rate in this circumstance would
(e.g., metaproterenol) to the nebulizer is indicated to tend to worsen the situation, because the patient’s
treat this threatening development. In fact, the manu- work of breathing would increase. Fewer mandatory
facturer of Mucomyst, Mead Johnson, has a premixed breaths would be delivered to the patient. Increasing
dosage of 10% acetylcysteine with 0.05% isopro- the preset tidal volume would not require any more or
terenol in 3 ml to 5 ml. In some clinical situations, any less negative pressure to open the demand valve.
MDI delivery of a bronchodilator is preferred before Therefore, the problem would not be corrected.
the administration of Mucomyst.
Switching to the control mode would not solve the
(1:580), (2:578–579), (8:165–167), (16:444). problem at hand. This action would remove the patient
from the weaning process, because the ventilator
IIIF1 would assume all of the patient’s work of breathing.
75. D. The effectiveness of closed-chest cardiac massage is Placing the patient in the control mode might cause the
largely associated with the ability to adequately com- patient to “fight” the ventilator.
press the heart between the sternum and the vertebrae. (1:976–986), (10:329–333).
Conditions such as marked scoliosis, kyphosis, pectus
excavatum, and pectus carinatum might preclude exter- IIIB2c
nal cardiac massage, because adequate compression 77. A. Bypassing the normal route of gas flow to the lungs
cannot occur between these structures. Pathological will impair important functions of the upper airways.
states causing a shift of the mediastinum result in sim- These functions include humidification, filtration, and
ilar difficulties. Likewise, crushed-chest injuries can heating. Decreased humidity in the inhaled gases will
create a situation making closed-chest cardiac massage cause secretions to change properties. The most im-
difficult to perform. The changes in the transthoracic portant changes will result in an increase in secretion
pressure that occur when the chest wall is alternatingly viscosity and a decrease in secretion water content. In-
compressed and decompressed during CPR, however, creased viscosity and decreased water content will
might assist the circulation of blood. The blood in pul- cause (1) a decrease in ciliary function, (2) dried, tena-
monary circulation can function as a reservoir. cious secretions, and (3) possibly mucous plugging of
(1:636–637), (15:1113–1120), (16:821–822). the artificial airway. Airway bleeding is not a common
problem related to maintaining a humidity deficit.
IIIC2c (1:607), (16:426–427).
76. C. Demand valves used in conjunction with SIMV
systems sometimes require an inordinate amount of IIB1a(3)
negative pressure on behalf of the patient to provide 78. D. Two types of CPAP systems are used clinically:
gas flow through the ventilator circuit. Demand valves continuous-flow CPAP and demand-flow CPAP. A
are intended to open in response to about –2 cm H2O continuous-flow CPAP system consists of blended
pressure. When demand valves do not operate accord- source gas at a high flow rate that flows continuously
ing to the manufacturer’s specifications, the patient’s past the patient, usually containing a large reservoir
work of breathing increases, which in turn creates a bag so that gas is available if the patient’s inspiratory
cascade of events that can jeopardize the weaning needs increase. The demand-flow CPAP system re-
process. quires the patient to generate a subatmospheric pres-
sure to open a one-way valve that enables a gas flow to
If the patient’s work of breathing appears to be in-
enter the system.
creasing beyond that expected for an SIMV system,
the CRT should (after troubleshooting the system) use In the situation described in this question, the problem
an alternate weaning procedure. Other weaning proce- cannot stem from a demand valve requiring an in-
dures available include continuous-flow IMV, T-piece creased effort to open on behalf of the infant, because

Chapter 6: Posttest 423

 the CPAP system in operation here is a continuous- STEP 2: Set up a proportion to solve for VA.
flow type. A continuous-flow CPAP system does not
V̇A 0.6
incorporate a demand valve. =
Q̇ C 1
If the pressure-relief valve, which is generally set to re-
lease at a pressure 5 cm H2O greater than the set CPAP Q̇ C = 5 L/min.
pressure, were stuck in the closed position, the pres-
0.6 X
sure would not drop to near 0 cm H2O. In fact, the =
pressure would not drop at all. If the gas flow rate 1 5 L/min.
through this continuous-flow system was too high, the
(0.6)(5)
pressure developed in the system would increase, not = 3 L/min.
decrease. 1
Although infants are obligate nose breathers, crying V̇A = 3 L/min.
causes air to move through the infant’s mouth. Ordi-
(15:102–103), (2:179).
narily, if the infant is resting quietly, no air passes
through the mouth—and the pressure in the CPAP sys-
tem is maintained. If the infant cries, however, system IIIC1d
pressure will be lost when the mouth opens. Pressures 81. B. This patient is experiencing a respiratory acidosis
might rise higher than the set pressure because of the because of hypoventilation. The underventilation is
increasing resistance developing in the system when manifested by the high PaCO2. The PaO2 is less than
the infant’s mouth closes suddenly. normal but is acceptable. Usually, a PaO2 greater than
60 torr is reasonable. With premature newborns, it is
(1:785–786, 865), (10:281–282, 349–351), critical to maintain a relatively low PaO2 to lessen the
(15:915–917), (16:682). risk of the development of retinopathy of prematurity.
Because the PaCO2 is indirectly related to the alveolar
IIIE3 minute ventilation, it can be decreased by either in-
79. A. The purpose of mucolytic administration is to thin creasing the tidal volume or increasing the ventilatory
tenacious mucus, thus facilitating its removal. Because rate. Because infant ventilators are usually time-cycled
the patient’s cough has become productive of sputum, and pressure-limited, they do not have a tidal volume
it is apparent that the therapeutic goal is being setting that can be directly manipulated.
achieved. There is no need to institute CPT for mobi-
Some time-cycled, pressure-limited ventilators pro-
lization of secretions, because the patient is expecto-
vide for direct control of the ventilatory rate, whereas
rating them himself. A bronchodilator would be
others enable the ventilatory rate to be a function of in-
indicated only if wheezing developed.
dependent inspiratory and expiratory time controls. In
(1:580), (8:165–167), (15:188–189). the case of the former, increasing the ventilatory rate
directly will decrease the PaCO2, because the minute
ventilation then increases. Increasing the inspiratory
IB10b time (which does not affect the rate) increases the tidal
80. D. V̇A = alveolar minute ventilation volume and increases the I:E ratio, which also de-
Q̇ C = pulmonary capillary minute perfusion creases the PaCO2.

V̇A alveolar minute ventilation For time-cycled, pressure-limited ventilators that have
= separate inspiratory time and expiratory time controls,
Q̇ C pulmonary capillary perfusion alterations in the inspiratory time will influence both
STEP 1: Calculate the cardiac output (Q̇ T) according the ventilatory rate and the I:E ratio. In this instance, a
to the following formula: decreased inspiratory time will increase the rate and
decrease the I:E ratio, thereby lowering the PaCO2.
heart rate  stroke volume = Q̇ T
The PIP is the preset pressure limit. For a given airway
100 beats/min.  0.05 liter = 5 L/min. resistance and lung compliance, the PIP, in conjunc-
We assume here that normal physiology prevails. tion with the inspiratory flow rate and inspiratory time,
Therefore, right-ventricular output will equal left- determines the tidal volume. Therefore, increasing the
ventricular output. Because the right ventricle’s out- PIP increases the tidal volume, which increases the
put enters the pulmonary vasculature, the Q̇ C will minute ventilation and lowers the PaCO2.
also be approximately 5.0 L/min. (1:845), (10:205–206, 211).

424 Chapter 6: Posttest

IIB1c liters/min., this system would provide a total flow of
82. C. As with any nebulizer, there are four main compo- 40 liters/min. to the patient. That is,
nents: a jet, a baffle, a capillary tube, and a reservoir. Delivered flow rate with flow meter set at 10 LPM
Water levels will not affect the performance of a neb- (air-O2 ratio at 40% O2 is 3:1)
ulizer, because the capillary tube extends into the
reservoir. Pneumatic nebulizers operating at flow rates 3 parts air  10 liters/min. = 30 liters/min.
lower than 10 L/min. should still produce an adequate 1 part O2  10 liters/min. = 10 liters/min.
amount of aerosol. Atomizers will produce mist, al-
though they lack a baffle. The baffle merely reduces delivered flow rate = 40 liters/min.
the particle size to a therapeutic range. Finally, the cap- The patient has an inspiratory flow rate of 55
illary tube must be attached; otherwise, the nebulizer liters/min.; therefore, the delivered flow rate is inade-
will be unable to produce any mist. quate for this patient’s inspiratory needs.
The CRT should carefully and aseptically reattach the Increasing the flow of oxygen to 15 liters/min. would
capillary tube. Failure to follow a sterile technique will correct this problem. Hence,
result in gross contamination of the nebulizer. Because
nebulizers produce water droplets, they are capable of Delivered flow rate with flow meter set at 15 LPM
spreading bacteria to the respiratory tract and causing (air-O2 ratio at 40% O2 is 3:1)
a nosocomial pneumonia. 3 parts air  15 liters/min. = 45 liters/min.
(5:127–129), (13:106–107). 1 part O2  15 liters/min. = 15 liters/min.

IIIC2a delivered flow rate = 60 liters/min.

83. B. When PEEP or CPAP are instituted, the goal should No flow rates were specified for the double flow-meter
be to achieve adequate oxygenation with an acceptable setup. An air entrainment mask would provide sufficient
FIO2, without compromising the patient’s cardiovas- gas flow, but the patient has a tracheostomy. Adding 50
cular function. Deciding when the optimum PEEP cc of reservoir tubing would not address the inade-
level has been reached with a patient involves evaluat- quate inspiratory flow rate.
ing several factors. The level of best PEEP for this pa- (1:755–758), (13:77–79), (16:391–394).
tient is 12.5 cm H2O. Although the SaO2 improved at
15 cm H2O of PEEP, the mixed-venous oxygen satura-
IIB1h(4)
tion (Sv̄O2) and the C.O. deteriorated. The gain in im-
proving arterial oxygenation is offset by the falling 85. D. Generally, pulse oximeters used in critical-care sit-
cardiovascular status. uations are accurate to within 2% to 4%. A ten-
dency exists for erroneously high readings at the low
When available, mixed-venous indices (Pv̄O2 and end of the scale, however (i.e., SaO2 80%). Accuracy is
Sv̄O2) provide a more global picture of oxygenation also affected by factors such as abnormal hemoglobin
than arterial oxygen indices (PaO2 and SaO2), because (methemoglobin and carboxyhemoglobin), bright, ex-
mixed venous blood is an average of all venous blood ternal ambient light, low perfusion states, patient and
returning to the heart, and is a reflection of the inter- probe motion, skin pigment, nail polish, vascular dyes,
action of the pulmonary and cardiovascular systems. and optical shunting.
The oxygenation status of arterial blood is primarily a
reflection of only the pulmonary system. Continuous Optical shunting can occur when part of the light emit-
monitoring of the Sv̄O2 provides a useful way to mon- ted from the light-emitting diode (LED) reaches the
itor circulatory changes, because the Sv̄O2 usually de- photodetector without passing through the finger.
creases with the deterioration of the patient’s Deeply pigmented skin and the use of black, blue, and
cardiovascular status. PEEP therapy (and cardiovascu- green nail polish can significantly affect the accuracy
lar drugs) can be titrated to an optimum dosage of pulse oximeters. The use of the vascular dyes, such
through continuous Sv̄O2 monitoring. In general, an as methylene blue (used to treat methemoglobinemia),
increase in the Sv̄O2 is a positive response, whereas a indigo carmine, and indocyanine green can also affect
decrease is undesirable. the pulse oximeter’s red and infrared light absorption.
Methylene blue can significantly decrease SpO2 read-
(10:272–274). ings.

IIIE1e(1) Low perfusion states, which occur during cardiac ar-

rest or cardiopulmonary bypass, will affect pulse
84. C. The air-oxygen ratio for an FIO2 of 0.40 is 3:1; i.e., oximeters and cannot be considered reliable for the de-
three parts air to one part oxygen. Operating at 10 tecting of a pulse or determining the SpO2.

Chapter 6: Posttest 425

 Typically, in the presence of bright, external ambient (Pierson, D., “Indications for Mechanical Ventilation
lights, the pulse search alarm flashes, and the digital in Acute Respiratory Failure,” 1983, Respiratory Care,
display is blank. Sensors should be covered with pp. 721–735).
opaque material to prevent the affect of ambient light.
Pulse oximetry can be misleading in the patient who IIA1a(2)
has recent exposure to carbon monoxide, because the 87. A. The room air-to-oxygen entrainment ratio (air:O2)
saturation measured by pulse oximetry is functional for an oxygen concentration of 35% is 5:1. With this
SaO2. The oximeter cannot distinguish abnormal oxygen device operating at 5 L/min., the patient will
forms of hemoglobin from oxygenated hemoglobin. receive a total flow rate of 30 L/min. (25 L/min. of air
For example, if 30% carboxyhemoglobin were pre- and 5 L/min. of oxygen). Because the patient’s inspi-
sent, the SaO2 measured via co-oximetry (fractional ratory flow demand is 35 L/min., the delivery system
SaO2) could be 60%, whereas the pulse oximeter would NOT meet or exceed his inspiratory flow rate.
would read 90%. Therefore, the patient would need to inspire an addi-
(1:928–929), (5:300–301), (10:97–98). tional 5 L/min. of room air to meet this requirement.
Entraining an additional 5 L/min. of room air would
cause the delivered FIO2 to be less than 0.35. To cor-
IC1b
rect this situation, the CRT could simply increase the
86. A. The CRT can obtain numerous ventilatory mea- oxygen flow rate to 6 L/min., which would provide a
surements when evaluating a patient’s need for me- total flow rate of 36 L/min. on an FIO2 of 0.35, ex-
chanical ventilation. Table 6-3 provides a list of the ceeding the patient’s inspiratory flow demand.
commonly measured lung mechanics. One must re-
member an important point when reviewing this table. (15:822–887), (2:410–412).
These values are only guidelines, not absolute indica-
tors for mechanical ventilation. In addition, the patient IIIC2c
must be alert and willing to cooperate for these mea-
88. C. During endotracheal suctioning of an intubated pa-
surements to be clinically significant.
tient, the tip of the suction catheter often touches the
carina (bifurcation of the trachea into the left and right
Table 6-5: Lung mechanics data mainstem bronchi), the epithelial lining of surrounding
portions of the trachea, and perhaps either the right or
Normal Critical left mainstem bronchus itself. These airway structures
Measurement Range Value contain mechanical or irritant receptors in their subep-
Tidal volume (VT) 5–8 ml/kg <5 ml/kg ithelial region. These receptors respond to mechanical,
Ventilatory rate (f) 12–20 breaths/min. >35 breaths/min. chemical, and physiological stimuli.
Minute ventilation Stimulation of these receptors can cause bron-
(V̇E) 18 L/min. >10 L/min.
chospasm, glottic closure, coughing, bradycardia, and
Vital Capacity (VC) 65 to 75 ml/kg <15 ml/kg
Maximum Inspiratory
decreased blood pressure. The cardiovascular re-
Pressure (MIP) –50 to –100 cm H2O < –20 cm H2O sponses (bradycardia and decreased blood pressure)
Maximum Expiratory are described as the vagovagal reflux.
Pressure (MEP) +100 cm H2O <40 cm H2O The vagovagal reflux might be stimulated during tra-
cheobronchial suctioning. If bradycardia develops, or
Tidal volume, carbon dioxide production, and physio- if a significant alteration in the patient’s heart rate and
logic dead space will determine the patient’s PaCO2 rhythm occurs, suctioning must be terminated imme-
level. The MEP, MIP, and VC are indicators of a pa- diately—and 100% oxygen should be administered.
tient’s ability to cough and clear secretions. If the pa- (1:154, 619), (16:602, 1138).
tient’s ventilatory frequency is excessively high, the
risk of respiratory muscle fatigue is also high. Finally,
an excessively high minute ventilation, especially if IIIC2a
the patient’s PaCO2 level is within the normal range, 89. C. This patient is displaying an adequate alveolar ven-
indicates a large physiologic dead space-to-tidal vol- tilation based on his arterial PCO2, pH, and HCO 3̄. His
ume ratio (VD/VT). Normally, the VD/VT should be ap- arterial PO2, however, is lower than it should be at an
proximately 0.3–0.4. A VD/VT of greater than 0.6 is FIO2 of 0.40 while on a PEEP of 8 cm H2O. According
considered an additional indicator for mechanical ven- to the alveolar air equation, the PaO2 should be 244
tilation. torr.

426 Chapter 6: Posttest

 IC1b
PaO2 = 0.4(760 torr  47 torr)  36 torr
( 0.4 +
0.8 )
1  0.4 91. B. The MIP reflects the status of a patient’s ventilatory
muscle strength. The MIP is measured when the pa-
tient’s airway is occluded for as long as 20 seconds.
= 0.4(713 torr)  36 torr(1.15) The ventilatory muscles generate the greatest inspira-
= 285.2 torr  41.4 torr tory pressure when inspiration begins at a lung volume
between FRC and RV. The MIP in normal, healthy,
= 244 torr young adults is between –80 cm H2O and –110 cm
H2O. In addition to inspiratory muscle strength and
Therefore, the arterial PO2 should be greater than 200 lung volume, the MIP is also determined by patient ef-
torr. Consequently, this patient is not oxygenating to the fort and ventilatory drive. Intubation does not affect
degree that one would expect. His ventilatory mechanics the MIP; rather, pressure is transmitted through a tube
are sufficient to support spontaneous breathing. His IBW with no loss in magnitude than through a normal air-
is 178 lbs, or 81 kg. Note the following calculations: way. Because the MIP is measured over a short time
interval (20 seconds), it cannot assess muscle en-
durance. An MIP of –30 cm H2O can predict success-
(MEN) IBW (lbs) =
ful weaning from mechanical ventilation for some
106 + [6  (height in inches  60)]
patients, but it should not be used as the sole predictor
= 106 + [6  (72 inches  60)] of successful weaning.
= 106 + 72 (1:825, 971, 1096), (2:260), (15:555–560, 1021).
= 178 lbs
IBW (kg) = 178 lbs IIIC2a
92. B. The CPAP mode should be used on a patient who
2.2 lbs/kg does not require ventilatory support, despite having
= 81 kg capillary shunting. Oxygen therapy is generally inef-
fective in relieving hypoxemia resulting from capillary
shunting, because the inspired oxygen cannot enter
This patient’s vital capacity (2.0 liters) is about 25 collapsed (or fluid-filled) alveoli. The underlying
cc/kg, which is greater than the guideline of 15 cc/kg problem in capillary shunting is loss of functional
used to suggest that spontaneous ventilation can be alveoli; therefore, effective treatment should be di-
supported. Additionally, his MIP is –35 cm H2O, rected toward restoring these alveoli to a functional
which indicates adequate ventilatory reserve and mus- state. The efficacy of PEEP (or CPAP, its equivalent in
cle strength necessary for spontaneous breathing. spontaneously breathing patients) lies in its capability
Again, the patient’s oxygenation status is suboptimal. to prevent or reverse alveolar collapse and increase
He is unable to maintain an adequate PaO2. Consider- lung volume, thus reducing the absolute or capillary
ing this clinical shortcoming and the patient’s adequate shunt.
ventilatory mechanics, the patient can likely breathe The efficacy of IPPB deserves mention in the treat-
on his own but will continue to require supplemental ment of atelectasis when discussing PEEP and CPAP.
oxygen. Therefore, instituting CPAP at 8 cm H2O pres- IPPB has been successfully employed to treat atelecta-
sure would be a reasonable therapeutic approach. Set- sis associated with the failure to take deep breaths. In
ting the IMV rate on zero (eliminating the mechanical delivering intermittent, elevated airway pressure to
breaths) will enable the administration of CPAP at the open atelectatic areas, one must ask the following
original level (i.e., 8 cm H2O pressure). question: Does the intermittent administration of pos-
(2:532). itive pressure during inspiration prevent atelectatic ar-
eas from recollapsing during the expiratory phase of
IIB1f(2) the breathing cycle?
90. D. A pressure-cycled ventilator terminates its inspira- (1:779, 783–786), (10:267–268).
tory phase when it has reached its preset pressure. If
the preset pressure is unable to be achieved because of
a leak, the ventilator will remain in the inspiratory IIB1c
phase. A deflated or ruptured ET tube cuff would pre- 93. D. The couplant chamber should be filled with dis-
vent the device from reaching the preset pressure; tilled water. Under normal circumstances, no commu-
therefore, the ventilator would not cycle off. nication between the couplant chamber and the
nebulization compartment exists. In the case of a leak
(1:845), (15:953–961).

Chapter 6: Posttest 427

 between the two compartments, solution in the nebu- creased from 70 torr to 85 torr. Additional PEEP be-
lization compartments will mix with distilled water yond 5 cm H2O is associated with a progressive de-
from the couplant chamber, causing contamination of crease in the C.O., PaO2, and oxygen delivery. Neither
the solution that is being nebulized. Nebulization will the blood pressure nor the heart rate significantly
not be affected. No electrical involvement is present changed.
related to the equipment presented here.
(2:535–545), (10:272–274), (15:727, 968–969).
(5:154–160), (13:108–109).
IIA1q
IIIB1d 97. C. Although a full MDI canister will contain approxi-
94. B. The most common cause of airway obstruction is mately 200 puffs, recording the number of puffs used
blockage of the pharyngeal passage by the posterior is not a practical or accurate method of determining
tongue. Extension of the neck with forward traction on how much medication is remaining. Placing the canis-
the mandible pulls the tongue forward, opening the air- ter in a bowl of water is the simplest method to deter-
way. mine the degree of MDI fullness. A full canister will
sink. If the canister is half full, it will float with the
(1:632–633), (15:40–41).
nozzle down and the flat bottom of the MDI above the
surface. An empty canister will float on its side.
IIB1k
95. A. The patient is holding the incentive spirometer cor- (13:104).
rectly; however, the patient is generating an inspiratory
flow rate that is too high and too rapid. A rapid inspi- IIIA2b(1)
ratory flow rate will not promote uniform distribution 98. C. Idiosyncrasy is a rare, paradoxical reaction to a
of air throughout the lungs. The inspiratory effort dur- specific drug (e.g., the onset of bronchospasm follow-
ing incentive spirometry should be relatively moder- ing the administration of a beta-two agonist). Toxicity
ate. With the IS device described here (Triflo II), the is a dose-related side effect observed in most people if
patient generally attempts to sustain elevation of the enough of the drug is given. Anaphylaxis describes an
ball in the first chamber for three seconds (600 cc/sec. extreme allergic reaction characterized by cardiovas-
flow rate). Then, the patient works at getting the balls cular collapse and respiratory distress. Tachyphylaxis
in the first two chambers to rise (900 cc/sec. flow rate). is diminution of effectiveness following frequent use.
The ball in the third chamber is not intended to elevate.
(8:32), (15:177).
If it rises, the patient is generating too rapid an inspi-
ratory flow rate, which will not help achieve the thera-
peutic objective. Flow-oriented incentive spirometry IIB1d
often helps prevent the patient from inspiring too 99. A. During a cardiac or respiratory arrest, the CRT must
quickly. know how to maximize oxygen delivery. Using an
oxygen reservoir, increasing the flow, and using the
(5:186–187), (13:250–251), (15:844–845). longest possible refill time all act to increase oxygen
delivery. Rapid ventilatory rates decrease the possible
IIIE2d refill time, thereby acting to decrease the oxygen de-
96. A. The purpose of PEEP is to increase the functional livery.
residual capacity (FRC), to reduce intrapulmonary
(1:649–650), (5:251), (15:1051, 1128).
shunting, and to improve oxygenation. PEEP elevates
the mean intrathoracic pressure, however, thereby im-
peding venous return and reducing the C.O. When IIIF1
PEEP is to be applied, the CRT should monitor the 100. D. Assuming that all ECG leads are intact and that the
composite effect of PEEP (i.e., the PaO2, C.O., oxygen monitor is functioning properly, attempting to arouse
delivery [C.O.  CaO2], and pulmonary compliance). the patient is unnecessary. Once pulselessness and the
All of these components should be considered because absence of spontaneous ventilations have been deter-
of the widespread ramifications of PEEP. mined, the first step is to begin one-rescuer CPR. A
precordial thump is inappropriate in this situation, be-
Based on the physiologic variables measured, the cause the rescuer did not witness the cardiac arrest.
PEEP of 5 cm H2O appears to be the optimum level. Upon initiating CPR, the rescuer should attempt to call
Although the C.O. decreased from 5.0 to 4.9 L/min., for help.
the oxygen delivery (C.O.  CaO2) improved from
925 ml/min. to 937 ml/min., and the arterial PO2 in- (1:630–637), (16:562).

428 Chapter 6: Posttest

IIA2 ufacturer as too rapid to promote uniform distribution
101. C. Indicator tape ensures that the conditions of steril- of the inspired gas.
ization are met but does not ensure that sterilization By changing the incentive spirometer to a volume-
has occurred. Biological indicators provide a reliable oriented device, the CRT can get a more accurate
monitoring method for equipment sterilization. measurement of the patient’s inspiratory volume and a
(1:59), (2:628–634), (17:525). better indication of the patient’s progress.
(2:451), (5:186–189), (13:248–251).
IIIA3
102. B. A patient who has croup (laryngotracheobronchitis) IIIE1b(1)
has likely been infected with the respiratory syncytial 104. C. Deflection of the pressure manometer in a counter-
virus (RSV) or the parainfluenza virus. Both of these clockwise direction reflects the patient’s effort to initi-
microorganisms warrant the use of contact precau- ate inspiration. The machine should be set so that the
tions. Contact precautions include the following re- patient can trigger inspiration with minimal effort. A
quirements: sensitivity of –1 to –2 cm H2O is usually appropriate. If
the patient is having to generate greater than –2 cm
1. a private room
H2O to cycle on the machine, the CRT should make the
2. gloves and handwashing
IPPB machine easier to trigger (i.e., make the machine
3. a gown
more responsive to the patient’s inspiratory efforts).
As usual, standard precautions must also be applied. (1:781), (5:194).
(Centers for Disease Control and Prevention).
IIB1c
IIIE1c 105. D. Because the oxygen-delivery device referred to
103. C. Incentive spirometry (IS) devices can generally be here is operating via an air-entrainment system, the
categorized as volume or flow oriented. Volume-oriented FIO2 delivered to the patient depends on the ratio of
devices actually measure and visually indicate the vol- entrained air to source gas (air:O2). Collection of wa-
ume achieved during a sustained maximum inspiration ter in the tubing will increase the resistance (frequently
(SMI). Flow-oriented devices (such as the Triflo) mea- termed back pressure) to gas flow, thus increasing the
sure and visually indicate inspiratory flow. This flow is pressure in the tubing and at the nebulizer air-entrain-
equated with volume by assessing the duration of in- ment port. This condition will decrease the amount of
spiration or time (flow  time = volume). air entrained, thus increasing the FIO2.

Because this patient is inspiring rapidly, the estimated (1:752–753), (15:18).

inspired volume might be grossly inaccurate. Volume
measurements derived from flow-oriented ISs should be IB7a
treated only as rough estimates of the actual inspired 106. C. Unless ET tube position has been confirmed by di-
volume, given the lack of precision of such devices and rect visualization of the carina by using a fiberoptic
the errors inherent in the bedside measurement of these laryngoscope, the chest X-ray coupled with other as-
short time intervals. A common problem in initial in- sessments should be used to confirm appropriate ET
struction is that the patient might tend to inspire tube position. In the adult patient, the tip of the tube
rapidly. Demonstration of the proper technique and ap- should be higher than 2 cm above the carina (generally
propriate coaching might eliminate her tendency to 4 to 6 cm), with the cuff below the glottis. If the tube
perform the maneuver at a rapid rate without a sus- is within 2 cm of the carina, unequal air distribution
tained effort at end-inspiration. between the two lungs might occur. Also, with neck
flexion and extension, the tube tip might move as
Furthermore, when the Triflo IS device is properly
much as several centimeters, so a tube tip that is posi-
used, the third ball should remain at the bottom of its
tioned within 2 cm of the carina might easily move
chamber, according to the manufacturer’s instructions.
into a mainstem bronchus (usually the right) with
According to the manufacturer’s literature, inspiratory
movement of the neck. Because it is not always possi-
flow rates of 600 and 900 cc/sec. are acceptable and
ble to view the carina, other landmarks can be used.
are intended to enhance uniform distribution of the in-
The carina is generally located around T6; therefore,
spired air throughout the lungs. Inspiratory flow rates
the tip should be between T2 and T4, or at the level of
that achieve or exceed 1,200 cc/sec., however, will
the aortic knob.
cause the ball in the third chamber to rise to the top.
Such inspiratory flow rates are considered by the man- (1:596–599), (15:835).

Chapter 6: Posttest 429

IID3 (“AARC Clinical Practice Guidelines. Oxygen Ther-
107. B. The application of mechanical ventilation might apy in the Acute Care Hospital,” 1991, Respiratory
lead to acid-base disturbances. When the PaCO2 is Care, 36, pp. 1410–1413).
lower than the patient’s normal value, and when the
pH reflects a respiratory alkalosis, excessive alveolar IIIE1e(2)
ventilation is present. Respiratory alkalosis can result 110. B. The selection of the type of oxygen-delivery device
from an excessive tidal volume or a rapid ventilatory to use for a particular patient is made after one consid-
rate. ers the range of FIO2 values that will be required, the
type of humidification system required, the patient’s
When a patient is receiving oxygen therapy, the PaO2
age, and the acceptance of the treatment or device. For
value might be normal or high, despite the presence of
this newborn who is requiring low to moderate levels
substantial pulmonary dysfunction. A PaO2 value of 100
of oxygen, an oxyhood is the most suitable device. Be-
torr might be called normal, but it is indicative of intra-
cause of its relative simplicity and capability to pro-
pulmonary shunting if the patient is breathing an FIO2
vide controlled and stable FIO2 values to the head and
of 0.80. In normal patients, the PaO2 value is approxi-
face of neonates and small infants, the oxyhood en-
mately five times higher than the percentage of oxygen
ables nursing care to other portions of the body with-
being inspired. Thus, the normal PaO2 on 40% oxygen
out affecting the FIO2. When used with an oxygen
is about 200 torr (i.e., 40  5 = 200).
blender and humidification system, oxyhoods can pro-
(1:216–217, 233, 238). vide warmed and humidified gas at any FIO2. Oxygen
concentrations can be regulated inside the hood with a
large-volume nebulizer by adjusting the nebulizer col-
IB5a lar setting, bleeding in air and oxygen mixtures, or at-
108. C. To assess a patient’s level of orientation, he should taching the nebulizer on a 100% oxygen setting to an
be asked questions to determine whether he is aware of air-oxygen blender. The air-oxygen blender with the
current person, place, and time. The question, “What is nebulizer set at 100% is the most desirable setup.
your full name?” assesses the patient’s orientation to
person. The query, “Where are you right now?” evalu- (2:359), (18:66, 282–284).
ates the patient’s orientation to place. Asking the pa-
tient, “What day is today?” identifies orientation to IIA1m(1)
time. 111. A. The correct method of measuring cuff pressure is to
The inquiry, “How long has it been since you received adjust the cuff volume and monitor the pressure si-
a breathing treatment?” would not ensure that the pa- multaneously. If the in-line manometer is attached to
tient knew the correct time of day or day of the week. the pilot balloon directly, air is compressed within the
Similarly, knowing the state in which one resides does system. When the pilot balloon is detached from the
not verify that the patient is aware he is in the hospital manometer, air is lost from the cuff (refer to Figure
or in some other health-care facility. 6-5). Consequently, an erroneously low reading will
result. In addition, when air is lost from the cuff, it in-
(1:301–302), (15:426). creases the chances of the patient aspirating any secre-
tions that are located above the cuff. The three-way
IIA1a stopcock establishes a communication among the sy-
ringe, manometer, and cuff simultaneously. Three-way
109. C. A patient complaining of pain radiating down his
stopcock enabling simultaneous communication
left arm is suspected of having a myocardial infarction
among the syringe, manometer, and cuff
(MI) until proven otherwise by a physician. Standard
procedure is to administer low-flow oxygen at 2 to 4 In Figure 6-5, the three handles on the stopcock indi-
L/min. via a nasal cannula if a patient is suspected of cate open channels. The side of the handle with no pro-
having an MI. The purpose for administering oxygen jections is the direction that is not in communication
to patients who recently have had an MI or who are with the other three (Figure 6-6).
suspected of being candidates for one is to reduce the
(1:609), (10:255–256), (13:133–134).
work of the heart and to make more oxygen available
to an irritable myocardium. An irritable myocardium
places the patient at risk for developing a dysrhythmia. IIB2p
High concentrations of oxygen have not been found to 112. C. Improper use of MDIs is prevalent. Among the
be helpful in most patients and might be contraindi- problems leading to improper MDI usage is a need for
cated in patients who have carbon dioxide retention. hand-breath coordination on behalf of the patient.

430 Chapter 6: Posttest

 In-line manometer

cm H2O

Air

ET tube Three-way stopcock

pilot balloon
ballon

Figure 6-5: Three-way stopcock enabling simultaneous communication

among the syringe, manometer and cuff.

No communication Patients who develop postextubation edema generally

exhibit difficulty breathing or shortness of breath,
along with inspiratory stridor. The inspiratory stridor is
usually audible with the unaided ear.
The treatment for postextubation subglottic edema
varies. Table 6-6 lists various forms of treatment for
this condition.
Table 6-6

Treatment for Postextubation Edema

Figure 6-6: Stopcock position indicating no communication • bland aerosol of sterile water or isotonic saline with
among the three components of this system
or without oxygen
• nebulized racemic epinephrine (0.5 ml of 2.25% in
Therefore, proper and detailed instruction by the CRT is para-
3 ml of normal saline)
mount. Deposition of the larger particles in the upper airways
• nebulized dexamethasone (1 mg in 4 ml of normal
increases systemic absorption and can lead to the development
saline)
of opportunistic fungal infections. Spacers reduce the need for • 60%–40% helium-oxygen mixture via a non-
hand-breath coordination, decrease the deposition of larger rebreathing mask
aerosol particles in the upper airways, and reduce systemic ab-
sorption by increasing vaporization and decreasing gas flow.
Also, having the spacer in-line obviates the need to have the According to the AARC Clinical Practice Guidelines
patient tilt her head back. With the spacer in place, all the pa- for Bland Aerosol Administration, bland aerosol is in-
tient has to do is actuate the MDI, inhale slowly to TLC, and dicated for upper-airway edema (i.e., laryngotracheo-
breath hold five seconds at end-inspiration. Spacers are espe- bronchitis, subglottic edema, postextubation edema,
cially useful for children and elderly patients. and post-operative management of the upper airway).

(15:810–813). (AARC Clinical Practice Guidelines for Bland

Aerosol Administration), (1:988), (10:337), (16:442).
IIIE3
113. D. Post-extubation edema is not an uncommon occur- IIID4
rence. All patients who are extubated should be 114. A. One of the objectives of therapeutic positioning or ki-
watched carefully for the signs and symptoms of sub- netic therapy is to facilitate the mobilization of secre-
glottic edema. tions. When a patient who has large amounts of retained

Chapter 6: Posttest 431

 secretions is placed on a kinetic therapy/lateral rotation symptoms described here and will only delay the
bed or begins intensive CPT, secretions might be mobi- needed change in the procedure.
lized so rapidly that suctioning might be required as fre-
(1:454–455, 582), (2:579), (8:218), (15:188).
quently as every 10 minutes (or more often) to keep the
airway patent.
IIIC1a
(RESTCUE Dynamic Air Therapy, Support Systems 118. A. Re-expansion of atelectatic alveoli is best accom-
International, Inc., product literature). plished by encouraging the patient to breathe deeply.
Incentive spirometry can be a useful way to manage a
IIA1f(3) cooperative patient, assuming that he is capable of
115. B. A fenestrated (“windowed”) tracheostomy tube is a generating a sufficient inspiratory effort. Spontaneous
special tube with an opening on the posterior portion breathing is preferable to positive-pressure breathing,
of the tube above the cuff. This opening is occluded by because spontaneous breathing provides better distrib-
the use of an inner cannula when a seal is preferred. In- ution of ventilation.
sertion of the inner cannula and inflation of the cuff re-
(1:772), (9:161), (15:856).
sults in the patient breathing through the tracheostomy
tube. When the inner cannula is removed, the patient
can speak after the tube is occluded by a decannulation IIIB2b
cannula, which seals the outer cannula, and after the 119. C. When ET suctioning is being performed, the CRT
cuff is deflated. In addition to speaking, the fenestrated must be mindful that, in addition to the removal of tra-
tube will enable the CRT to assess the patient’s ability cheobronchial secretions, lung volume is also being
to have the tube removed. evacuated. The removal of air from the lungs during
(1:614), (13:131). the suction procedure can cause hypoxemia. The hy-
poxemia, in turn, can result in cardiac dysrhythmias,
especially if the patient already has an irritable my-
IC1a
ocardium. A variety of dysrhythmias can develop, one
116. B. In terms of oxygen therapy to premature infants, of which is premature ventricular contraction (PVC).
concern exists about providing too much or too little A PVC occurs when a ventricular ectopic focus stim-
oxygen. The dangers of hypoxemia are many and well ulates ventricular depolarization. This ectopic stimulus
understood. The dangers are more significant with im- is out of phase with the regular cardiac cycle, resulting
mature infants who are still developing neurologically. in a compensatory pause before the next regular ven-
The danger of hyperoxemia includes retinopathy of tricular contraction.
prematurity, which is believed to occur at PaO2s
greater than 100 mm Hg. Pulse oximetry is accurate to Preoxygenating the patient with 100% oxygen will
within 4% for SpO2 readings in the range of 70% usually reduce the risk of developing hypoxemia, be-
and higher. The accuracy decreases to 6% when the cause the blood-oxygen stores become elevated. The
SpO2 dips lower than 70%. Therefore, an SpO2 reading increased level of oxygenation in the blood might be
of 95% could be as much as 99%, which would repre- enough to stave off the development of cardiac dys-
sent (in most cases) a PaO2 that is greater than 100 mm rhythmias. The method of preoxygenating a chronic
Hg. In addition, it is a good idea to keep the PaO2 of CO2 retainer involves using lower levels of oxygen be-
the premature infant in the range of 50 to 80 mm Hg to fore suctioning, thereby lowering the risk of developing
provide some margin of safety. Under normal circum- microatelectasis or oxygen-induced hypoventilation if
stances, an SpO2 of 90% will approximate a PaO2 of the patient is breathing via his or her hypoxic drive. It
60 mm Hg. is inappropriate to use lidocaine prophylactically to re-
duce the risk of PVCs, although lidocaine is an effec-
(15:492–494), (16:375, 862–863). tive antidysrhythmic agent.

IIIE3 (1:619–620), (2:430), (16:602).

117. A. Cromolyn sodium occasionally causes cough and
bronchospasm. Administering a bronchodilator con- IIB1j
currently or before the cromolyn sodium can prevent 120. B. Minimal oxygen flows of 10 to 12 L/min. are re-
bronchospasm. If this sequence is not effective, the pa- quired to maintain oxygen percentages between 40%
tient’s medication should be reviewed. A temperature and 50% and to limit carbon dioxide concentrations
and a rash might be indicative of an allergic response lower than 1%. Although supplemental flow from an
to the cromolyn sodium. An allergic reaction is un- ultrasonic nebulizer would be sufficient to maintain
common with cromolyn sodium, but it can occur. Giv- minimum carbon dioxide levels, it would not increase
ing the medication faster or slower will not help the the oxygen concentration. An open-top tent would pre-

432 Chapter 6: Posttest

 vent carbon dioxide buildup, but it is not recommended rhythm indicates that the procedure should be stopped
when oxygen administration is desired. and that the practitioner should administer oxygen to
the patient while further evaluation is made.
(5:78–79), (18:285–286).
(1:619–620), (2:430), (15:836).
IIIA2e
121. D. When the expiratory flow is interrupted as the in- IIA1d
spiratory flow begins, auto-PEEP develops. In other 123. D. Because of concern about the possibility of con-
words, the ventilator cycles to inspiration before the tracting a disease from a patient or vice-versa, mouth-
expiratory flow has reached the baseline. The flow- to-valve mask devices for resuscitation have become
time waveform in Figure 6-7 illustrates this situation. common. Health-care workers are reluctant to perform
mouth-to-mouth resuscitation for this reason. Newer
Expiratory Flow mouth-to-valve mask units on the market provide an
Does Not Reach oxygen inlet, a filter to protect both the patient and res-
Baseline
cuer, an exhalation valve, and a lightweight, transpar-
Inspiration Inspiration Switch over ent mask.
from Inspiration
to Expiration (5:251). (Hess, D., “Evaluation of Mouth-To-Mask
Ventilation Devices,” 1989, Respiratory Care, 34,
p. 191).
Baseline
Flow

Time
IIIA2d
Inspiratory Flow 124. B. Bronchial hygiene in this chest trauma patient
Expiration Begins Before presently requires a modification in procedures. Pain
Expiratory Flow
Ends
medication before therapy might improve therapeutic
tolerance. If the patient does not tolerate the procedure
Figure 6-7: A flow-time waveform depicting the presence of any better with the coordination of pain medication,
auto-PEEP. Note how the gas flow rate during expiration
does not reach the baseline and how the flow rate during the CRT should review the patient’s chart to determine
the ensuing inspiration interrupts the preceding expiratory whether the agitation is positional. Modifying the pro-
flow rate. cedure by eliminating clapping should also be at-
tempted. Paralyzing and sedating are not indicated.
The inspiratory flow rate is shown as a positive upward
(5:251).
deflection along the flow-time waveform. Inspiration
continues as the inspiratory flow rate plateaus. At a
ID1b
preset time, inspiratory flow shuts off and expiration
begins. Expiratory flow is designated by the down- 125. B. The medical literature is replete with evidence that
ward slope above the baseline from the end of inspira- deep breathing can reverse atelectasis. Incentive
tion and continues below the baseline. Once below the spirometry incorporates mechanical devices to en-
baseline, the expiratory flow moves in the direction of courage the patient to breathe deeply. These devices
the baseline, or zero flow. are either flow-oriented or volume-oriented, enabling
the patient and CRT to establish therapeutic goals
The expiratory flow is prevented from reaching zero, based on having the patient attain various levels of
however, because the inspiratory flow begins before flow rates or volumes.
the expiratory flow reaches zero.
The development of atelectasis following upper-ab-
(1:952–953), (16:319–320, 322). dominal surgery is quite common. Atelectasis will de-
crease compliance and create a restrictive impairment.
IIIA2b(4) At the same time, it will lower the intrapleural pressure
122. A. Hypoxemia, vagal stimulation, mucosal trauma, in the affected area of the lung, producing findings
and increased intracranial pressure are all potential such as elevated hemidiaphragms or even mediastinal
complications of the ET suctioning procedure. Recog- shift, if extensive. The reduced lung volumes caused
nizing the difference among the various complications by the atelectasis will result in an increased work of
and their signs and symptoms is necessary to ensure breathing. Incentive spirometry promotes deep inspi-
patient safety. Tachycardia is frequently caused by hy- ration, which increases the tethering forces surround-
poxemia or patient agitation, whereas bradycardia is ing the parenchyma. As the alveoli open because of
more commonly caused by vagal stimulation or parox- these forces, lung volumes increase, and the work of
ysmal coughing. Any major change in cardiac rate or breathing decreases.

Chapter 6: Posttest 433

 Incentive spirometry does not increase the strength or STEP 2: Compute the expiratory time (TE); the TCT
improve the endurance of inspiratory muscles, as does and the TI are known.
an inspiratory muscle trainer. Incentive spirometry
TCT = TI + TE
does involve the use of these ventilatory muscles,
however, and does contribute to their improved per- TE = TCT  TI
formance. Nonetheless, only an inspiratory muscle-
= 6 sec.  1 sec.
training device can be expected to increase the
strength and endurance of inspiratory muscles. = 5 sec.
(1:774), (16:529–530). (“AARC Clinical Practice STEP 3: Use the following formula to calculate the
Guidelines. Incentive Spirometry,” 1991, Respiratory I:E ratio:
Care, 36, pp. 1402–1405).
TI TE
I:E = :
IIA1h(5) TI TI
126. A. Oxygen analyzers, which function according to the 1 sec. 5 sec.
polarographic principle, incorporate an anode and a = :
cathode connected by an electrolyte gel or solution. 1 sec. 1 sec.
Oxygen molecules diffuse through a membrane and The I:E ratio equals 1:5.
are reduced at the cathode by releasing electrons,
The I:E ratio is the relationship between the time used
while the metal anode gains these electrons and is ox-
to inspire and the time used to exhale, plus any
idized. In this oxidation/reduction reaction, oxygen
pause(s) between breaths.
molecules are consumed. The greater the number of
oxygen molecules in the sample, the larger the electric (1:860), (10:205–206).
current produced. The higher electric current corre-
lates with a high FIO2. IIB1m
(5:283–284), (13:185–186), (17:209–210, 213). 129. B. Aneroid manometers are used on many types of
respiratory-care equipment for measuring pressure. A
IIID7 CRT can check these manometers periodically to ensure
their accuracy. The CRT should check the gauge against
127. D. ABGs are traditionally thought of as the standard
a mercury column or water column. Mercury and water
for assessing ventilation and oxygenation. A combina-
columns are not subject to fatigue or drift, which ac-
tion of assessments should be used to evaluate the ef-
company gauges that have moving or electrical compo-
fectiveness of mechanical ventilation, however. When
nents. Consequently, the CRT can rely on their accuracy.
the patient is first connected to the ventilator, the ini-
The two devices should be linked to a syringe via a
tial step is to listen to breath sounds to confirm ade-
three-way stopcock. In this manner, the pressures can be
quate volume delivery and proper ET tube placement.
adjusted with a syringe until the aneroid manometer and
Monitoring the tidal volume of the mechanically ven-
the mercury manometer read the same level of pressure
tilated patient is crucial. Discrepancies in the set ver-
(refer to Figure 6-8). A calibrated “super syringe” is
sus the measured tidal volume can alert the
used to calibrate devices measuring volume, not pres-
practitioner to leaks in the ventilator circuit or an ET
sure.
tube cuff leak.
(10:255).
(1:909), (10:234).
IIIF1
IA1f(2)
130. B. The oxygen flow rate, the reservoir capacity, and
128. B. The I:E ratio, based on the respiratory data pre-
the bag-recovery (refilling) time are the factors in de-
sented, is calculated as shown:
termining the delivered FIO2. A flow rate greater than
STEP 1: Determine the length of each ventilatory cy- 8 L/min. is required. Bag reservoir refill time should
cle or total cycle time (TCT). be maximized by a short inspiratory time.
60 sec./min. (5:4–5), (13:238).
= TCT
f
IIIE1g(4)
60 sec./min. 131. B. Ideally, cuff pressures should be maintained be-
= 6 sec./breath
10 breaths/min. tween 25 and 27 cm H2O. Using the minimal leak
technique, the practitioner can ascertain whether the

434 Chapter 6: Posttest

 Mercury column
Aneroid manometer

mm Hg
mm Hz

Three-way stopcock
Figure 6-8: Method for verifying the accuracy of an aneroid manome-
ter by using a mercury column.

cuff is inflated to the appropriate level to seal the air- (1:380–386), (2:239–240), (6:36–40), (11:36–39),
way. If 30 cm H2O are required to seal the airway, a (15:461).
larger ET tube needs to be inserted to prevent mucosal
damage. IIIA2b(1)
(1:610), (10:255–256), (15:827). 133. C. If a patient refuses therapy, the CRT must clearly
communicate the indications for the treatment to the
patient. If that does not help, the CRT must document
IA1d
the refusal in the medical record. The problem must
132. D. Normally, at least 75% of the vital capacity can be ex- also be communicated to the patient’s nurse or physi-
haled in the first second of a FVC maneuver. The FVC is cian. Trying to coerce or force the patient to take treat-
often expressed as a percentage of the forced expiratory ments can be a violation of the patient’s rights or might
volume in one second (FEV1); that is, FEV1/FVC or even constitute battery. Enlisting the aid of family
FEV1%. Patients who have obstructive lung disease have members to encourage a patient to cooperate might be
low expiratory flow rates and exhale fewer than 65% of appropriate.
their vital capacities in the first second. Restrictive lung-
disease patients have small vital capacities and often ex- (1:26).
hale up to 100% of their vital capacities in one second.
Subjects who have normal pulmonary function exhale IC2a
75% to 83% of their vital capacities in one second. Table 134. B. Several methods are used to compare a patient’s
6-7 outlines the normal values for measurements ob- FEV1 to the predicted normal value and to quantify the
tained from an FVC maneuver. severity of pulmonary impairment. A common method
of comparison is to compute a percentage of the pre-
Table 6-7: Normal values for measurements
obtained from a forced vital capacity maneuver
dicted normal value (i.e., actual/predicted  100). De-
termining whether the subject’s value is within one or
Measurement Range two standard deviations of the predicted normal value
is an alternate method used in some cardiopulmonary
FVC 5.00 L laboratories. Although ranges of percent predicted
FEV1 4.20 L vary somewhat, commonly a range of 80% to 120% is
FEV1/FVC or FEV1% 75%–85%
considered normal. Abnormal ranges include 65% to
FEV2/FVC or FEV2% 86%–93%
FEV3/FVC or FEV3%
79% for mild impairment, 50% to 64% for moderate
94%–97%
FEF200–1200 8.70 L/sec. impairment, and less than 50% for severe impairment.
FEF25%–75% 5.20 L/sec. In the example cited here, the patient’s FEV1 (63%)
and FEV1% (65%) fall within the range categorized as
The percentage of the forced expiratory volume ex- moderate obstructive impairment. At the same time, it
pired in one second (FEV1%) is calculated as follows. would be useful to know whether this degree of airway
obstruction is reversible; hence the recommendation of
FEV1 (liters) a postbronchodilator study.
 100 = FEV1%
FVC (liters) (1:380–386), (6:36–40), (11:36–43).

Chapter 6: Posttest 435

IIIB2d 60 beats/min. In the clinical setting, sinus bradycardia
135. C. The normal cough reflex has four phases. The initial is most often associated with an increased level of
event, known as irritation, occurs when a stimulus pro- parasympathetic tone, as may be produced by vagal
vokes an impulse from the sensory fibers to the cough stimulation or adrenergic blocking agents. Manipula-
center. The cough center then stimulates the respiratory tion of tracheostomy ties or of the tube itself, perfor-
muscles to trigger a deep inspiration. During the third mance of a Valsalva maneuver, or tracheal suctioning
phase, known as the compression phase, the glottis can increase vagus nerve tone and cause transient sinus
closes (vocal cords adduct) and expiratory muscles bradycardia.
(predominantly abdominal muscles) contract force- (1:326).
fully, raising the intrapleural pressure well above at-
mospheric pressure. In the final (or expulsion) phase, IIIE1d(3)
the glottis opens (vocal cords abduct), and the contin- 139. A. Small-volume nebulizers operating continuously
ued contraction of respiratory muscles causes a violent, deliver medication to the patient’s airways only during
expulsive egress of air from the lungs. inspiration. During exhalation, the medication is
(1:792–793), (9:21–23), (15:39). vented to the atmosphere. To optimize the nebulization
of the drug, most small-volume nebulizers can be
IIIC1a equipped with an adaptor for intermittent nebulization.
136. C. When teaching diaphragmatic breathing, the CRT
should place a hand over the epigastric region directly
below the xiphoid process. The patient is instructed to
inhale air “into the abdomen” in a forceful attempt to
lift the CRT’s hand.
(2:444).

ID1c
137. B. Anti-inflammatory agents, corticosteroids, and cro-
molyn sodium are the most important drugs in the
treatment of chronic asthma. The early and late phases
of an allergic response, as well as bronchoconstriction
caused by exercise and cold air, can be inhibited by the Figure 6-9: Small-volume nebulizer equipped with an adap-
tor for intermittent nebulization.
ongoing administration of cromolyn sodium. Prophy-
lactic treatment with cromolyn sodium will inhibit the Figure 6-9 illustrates a small-volume nebulizer with a
release of chemical mediators (e.g., histamine, thumb control port operated by the patient. When the
leukotrienes, heparin, ECF-A, etc.) from the mast cells, patient places his thumb over the small hole, nebuliza-
which causes the inflammation. tion occurs. The thumb control port is covered during
inspiration and is uncovered during exhalation. Be-
Similarly, corticosteroids will interfere with the release
cause no nebulization occurs during exhalation with
of chemical mediators from the mast cell, block in-
the thumb control port open, the time for complete
flammatory effects of arachidonic acid metabolites,
drug nebulization increases. Therefore, total treatment
and increase responsiveness to beta agonists. In the
time increases. A patient needs to have adequate coor-
asthmatic patient, anti-inflammatory agents are used to
dination to accomplish this form of nebulization.
prevent mucosal edema, bronchospasm, and mucous
plugging. The National Asthma Education Program al- (1:694–697), (5:128).
gorithm for the treatment of chronic moderate asthma
recommends the use of anti-inflammatory agents in a IIIE1d(3)
patient with 60% to 80% baseline values for the FEV1 140. C. Airway temperatures over 44ºC can potentially burn
or the peak expiratory flow rate. the patient’s mucosal lining. The first response would
(National Asthma Education Program, Executive be to disconnect the patient from the gas source imme-
Summary: Guidelines for the Diagnosis and Manage- diately, and apply manual ventilation. The temperature
ment of Asthma, June 1991), (1:455), on the heating unit should be turned down and the unit
(8:137–139, 214–219). inspected for malfunction. Silencing the alarm will not
help the patient, nor will turning off the ventilator. The
IIID5 temperature of a humidified gas should be maintained
between 32ºC and 37ºC.
138. A. Sinus bradycardia meets all the criteria for a normal
sinus rhythm except for the heart rate, which is below (1:855), (10:166, 294–295).

436 Chapter 6: Posttest

 References
1. Scanlan, C., Spearman, C., and Sheldon, R., Egan’s 12. Koff, P., Eitzman, D., and New, J., Neonatal and Pedi-
Fundamentals of Respiratory Care, 7th ed., Mosby- atric Respiratory Care, 2nd ed., Mosby-Year Book,
Year Book, Inc., St. Louis, MO, 1999. Inc., St. Louis, MO, 1993.
2. Kacmarek, R., Mack, C., and Dimas, S., The Essen- 13. Branson, R., Hess, D., and Chatburn, R., Respiratory
tials of Respiratory Care, 3rd ed., Mosby-Year Book, Care Equipment, J. B. Lippincott, Co., Philadelphia,
Inc., St. Louis, MO, 1990. PA, 1995.
3. Shapiro, B., Peruzzi, W., and Kozlowska-Templin, R., 14. Darovic, G., Hemodynamic Monitoring: Invasive and
Clinical Applications of Blood Gases, 5th ed., Mosby- Noninvasive Clinical Application, 2nd ed., W. B. Saun-
Year Book, Inc., St. Louis, MO, 1994. ders Company, Philadelphia, PA, 1995.
4. Malley, W., Clinical Blood Gases: Application and 15. Pierson, D., and Kacmarek, R., Foundations of Respi-
Noninvasive Alternatives, W. B. Saunders Co., ratory Care, Churchill Livingston, Inc., New York,
Philadelphia, PA, 1990. NY, 1992.
5. White, G., Equipment Theory for Respiratory Care, 16. Burton et al., Respiratory Care: A Guide to Clinical
3rd ed., Delmar Publishers, Inc., Albany, NY, 1999. Practice, 4th ed., Lippincott-Raven Publishers,
6. Ruppel, G., Manual of Pulmonary Function Testing, Philadelphia, PA, 1997.
7th ed., Mosby-Year Book, Inc., St. Louis, MO, 1998. 17. Wojciechowski, W., Respiratory Care Sciences: An In-
7. Barnes, T., Core Textbook of Respiratory Care Prac- tegrated Approach, 3rd ed., Delmar Publishers, Inc.,
tice, 2nd ed., Mosby-Year Book, Inc., St. Louis, MO, Albany, NY, 2000.
1994. 18. Aloan, C., Respiratory Care of the Newborn and
8. Rau, J., Respiratory Care Pharmacology, 5th ed., Child, 2nd ed., Lippincott-Raven Publishers, Philadel-
Mosby-Year Book, Inc., St. Louis, MO, 1998. phia, PA, 1997.
9. Wilkins, R., Sheldon, R., and Krider, S., Clinical As- 19. Dantzker, D., MacIntyre, N., and Bakow, E., Compre-
sessment in Respiratory Care, 3rd ed., Mosby-Year hensive Respiratory Care, W. B. Saunders Company,
Book, Inc., St. Louis, MO, 1995. Philadelphia, PA, 1998.
10. Pilbeam, S., Mechanical Ventilation: Physiological 20. Farzan, S., and Farzan, D., A Concise Handbook of
and Clinical Applications, 3rd ed., Mosby-Year Book, Respiratory Diseases, 4th ed., Appleton & Lange,
Inc., St. Louis, MO, 1998. Stamford, CT, 1997.
11. Madama, V., Pulmonary Function Testing and Car-
diopulmonary Stress Testing, 2nd ed., Delmar Publish-
ers, Inc., Albany, NY, 1998.

Chapter 6: Posttest 437

 APPENDIX 1

Quick Reference Material—Clinical Data

Cylinder Sizes and Correction Factors 440

Atmospheric Pressure Equivalents 440
Causes of Hypoxemia 440
Classification of Hypoxemia 440
Criteria for Instituting Mechanical Ventilation 441
Indications for PEEP 441
Mechanical Ventilation Weaning Criteria 441
Static and Dynamic Compliance Changes () 442
Static and Dynamic Compliance Changes () and Associated Diagnoses 442
Acid-Base Interpretations 443
Normal Adult Hemodynamic Values 443
Normal Adult Systemic Arterial Pressures 444
Pulmonary Function Interpretations 444
Pulmonary Function Interpretations and Values 444
Blood-Gas Analyzer Electrode Accuracy and Calibration Ranges 444
Physical Examination of the Chest for Some Common Pulmonary
Diseases and Conditions 445

439
 Cylinder Sizes and Correction Factors

Cylinder Size Correction Factor

D 0.16 L/psig
E 0.28 L/psig
G 2.41 L/psig
H or K 3.14 L/psig

Atmospheric Pressure
Equivalents

760 mm Hg
760 torr
1034 cm H2O
14.7 psig
101.33 kPa

Causes of Hypoxemia

Decreased FIO2 or PIO2

A/C membrane diffusion impairment
Hypoventilation (↓ V̇A)
R-L shunting
V̇A/V̇C mismatching

Classification of Hypoxemia

Classification PaO2 (torr)

Normal 80–100
Mild 60–79
Moderate 40–59
Severe less than 40

440 Appendix 1
 Criteria for Instituting Mechanical Ventilation

Measurement Normal Value Critical Value

VC 65–75 ml/kg < 15 ml/kg

V̇E 5–6 L/min. > 10 L/min.
f 12–20 breaths/min. > 35 breaths/min.
VT 5–7 ml/kg < 5 ml/kg
MIP (20 sec.) –80 to –100 cm H2O > –20 cm H2O ( 20 sec.)
VD/VT 0.3–0.4 > 0.6
PaCO2 35–45 torr > 55 torr
pH 7.35–7.45 < 7.25
PaO2 80–100 torr < 50 torr at 0.50 FIO2
P(A-a)O2 5–10 torr > 350 torr at 1.00 FIO2

Indications for PEEP

PaO2 < 60 torr on FIO2 0.60–0.80

Q̇S /Q̇ T > 0.30
P(A-a)O2 > 300 torr on FIO2 1.0

Mechanical Ventilation Weaning Criteria

Physiologic Measurement Acceptable Values

Spontaneous f  25 breaths/min.
Spontaneous VT  3 ml/kg
VC  10–15 ml/kg
MIP  –20 to –25 cm H2O
( 20 sec.)
Spontaneous V̇E < 10 L/min.
CT on ventilator > 30 ml/cm H2O
Q̇ S /Q̇ T < 15%
VD/VT < 0.55–0.60
PaO2/FIO2 > 100
P(A-a)O2 on 100% O2 < 300–350 torr
PaO2 on 100% O2 > 300 torr
PaO2 on < 40% O2  60 torr
PaO2/PaO2 > 0.15

Appendix 1 441
 Static and Dynamic Compliance Changes ()

Condition  Cstatic  Cdynamic

Increased Raw No  Decrease

Decreased Raw No  Increase
Increased CTotal Increase Increase
Decreased CTotal Decrease Decrease
Increased Raw and decreased CTotal Decrease Decrease
Decreased Raw and increased CTotal Increase Increase
Increased CTotal and increased Raw Increase No  or decrease
Decreased CTotal and decreased Raw Decrease No  or increase

Static and Dynamic Compliance Changes ()

and Associated Diagnoses

Cstatic Cdynamic Diagnosis

Decrease Decrease High-pressure (cardiogenic) pulmonary edema

Decrease Decrease Pneumonia
Decrease Decrease Adult respiratory distress syndrome (ARDS)
Decrease Decrease Atelectasis
Decrease Decrease Pneumothorax
No  Decrease Bronchospasm
No  Decrease Retained secretions

442 Appendix 1
 Acid-Base Interpretations

Acid-Base Abnormality PaCO2 (mm Hg) HCO 3̄ (mEq/liter) pHa

Uncompensated (acute)
respiratory acidosis > 45 22–26 < 7.35
Compensated (chronic)
respiratory acidosis > 45 > 26 Just under 7.35
Uncompensated (acute)
respiratory alkalosis < 35 22–26 > 7.45
Compensated (chronic)
respiratory alkalosis < 35 < 22 Just above 7.45
Uncompensated (acute)
metabolic acidosis 35–45 < 22 < 7.35
Compensated (chronic)
metabolic acidosis < 35 < 22 Just below 7.35
Uncompensated (acute)
metabolic alkalosis 35–45 > 26 > 7.45
Compensated (chronic)
metabolic alkalosis > 45b > 26 > 7.45b
aCompensatory mechanisms ordinarily do not return the pH value to within normal limits. When compen-
sation has occurred, the pH will generally be just below the lower limit of normal (compensated acidosis)
or just above the upper limit of normal (compensated alkalosis), depending on the primary acid-base dis-
turbance.
bThe PaCO rarely exceeds 50 mm Hg during a compensated metabolic alkalosis. Therefore, the pH in
2
this situation will generally be somewhat higher than the upper limit of normal.

Normal Adult Hemodynamic Values

Physiological Measurement Acceptable Range

CVP 0–7 cm H2O (0–5 mm Hg)

RA pressure < 10 mm Hg
RV diastolic 0–8 mm Hg
RV systolic 15–38 mm Hg
PA diastolic 4–15 mm Hg
PA systolic 12–30 mm Hg
PA mean 8–20 mm Hg
PCWP mean 6–12 mm Hg
LV diastolic 4–11 mm Hg
LV systolic 80–140 mm Hg
Cardiac output (C.O.) 4–8 L/min.
Stroke volume (SV) 60–130 ml
Cardiac index (CI) 2.5–4.2 L/min./m2
Q̇ S /Q̇ T < 5.0%

Appendix 1 443
 Normal Adult Systemic
Arterial Pressures

Measurement Acceptable Range (mm Hg)

Diastolic 60–90
Systolic 100–140
Mean 70–100

Pulmonary Function Interpretations

Obstruction

Measurement Restriction Air Trapping Hyperinflation

TLC Decreased Normal Increased

VC Decreased Decreased Normal
FRC Decreased Increased Increased
RV Decreased Increased Increased
RV/TLC Normal Increased Increased

Pulmonary Function Interpretations and Values

Obstruction

Measurement Normal Restriction Air Trapping Hyperinflation

TLC (ml) 6000 3600 (60% pred.) 6000 (100% pred.) 7500 (125% pred.)
VC (ml) 4800 2850 (59% pred.) 3600 (75% pred.) 4575 (95% pred.)
FRC (ml) 2400 1400 (58% pred.) 3500 (145% pred.) 4000 (167% pred.)
RV (ml) 1200 750 (63% pred.) 2400 (200% pred.) 2925 (243% pred.)
RV/TLC (%) 20% 20% 40% 40%

Blood-Gas Analyzer Electrode Accuracy

and Calibration Ranges

Electrode Accuracy Calibration

pH  0.01 6.840 (low)

7.384 (high)
PCO2  2.0% or  1 torr at 40 torr 5.0% CO2 (low)
10.0% CO2 (high)
PO2  3.0% or  2.5 torr at 80 torr 0% O2 (low)
12% or 20% O2 (high)

444 Appendix 1
 Physical Examination of the Chest for Some Common Pulmonary Diseases and Conditions*
Disease/Condition Inspection Palpation Percussion Auscultation

Chronic bronchitis Prolonged exhalation; accessory ventilatory- Generally normal Usually unremarkable; Early inspiratory crackles; expiratory
muscle use and cyanosis in severe form or hepatomegaly with cor wheezing depending on severity;
during acute exacerbation; thoracic excursions pulmonale prolonged exhalation; loud P2 with
might be normal or decreased depending on pulmonary hypertension (cor pul-
severity; jugular venous distention with cor monale)
pulmonale; slight overweight appearance
Pulmonary Barrel chest; increased AP chest-wall diameter; Decreased chest-wall expan- Hyperresonance; de- Dimished breath sounds; heart
emphysema kyphosis; accessory ventilatory-muscle use; sion; reduced and/or more creased diaphragmatic sounds distant; prolonged
prolonged exhalation; clavicular lift during midline point of maximum excursions exhalation
inspiration; pursed-lip breathing; prominent impulse; decreased tactile
anterior chest with elevated ribs; emaciated fremitus
appearance
Asthma Accessory ventilatory-muscle use; prolonged Frequently normal; decreased Frequently normal; Prolonged exhalation and expiratory
exhalation; intracostal and supraclavicular chest-wall expansion and hyperresonance during wheezing; inspiratory and expiratory
retractions based on severity; increased AP decreased tactile fremitus acute exacerbation wheezing, or diminished air move-
diameter if severe depending on severity ment with severity
Bacterial (lobar) Accessory ventilatory-muscle use and Reduced thoracic expansion Dull percussion note or Bronchial breath sounds over
pneumonia cyanosis depending on severity; increased over affected lung area; decreased resonance consolidated area; if bronchial ob-
ventilatory rate increased tactile fremitus over over consolidated area struction is total, breath sounds will
consolidated (affected) area be diminished or absent; coarse in-
spiratory crackles in affected region
Lobar atelectasis Increased ventilatory rate (accessory-muscle Decreased tactile fremitus over Dull percussion note Decreased or absent breath sounds
use) and shallow breathing; mediastinal and atelectatic region; reduced over atelectatic region over collapsed region (no air entry);
tracheal shift toward affected (atelectatic) chest-wall expansion over late inspiratory crackles indicate air
region; cyanosis if severe affected region entry through partial obstruction,
inflating atelectatic alveoli
Pneumothorax Tachypnea (ventilatory distress) and cyanosis Absent tactile fremitus over Hyperresonance over Absent or diminished breath
(unilateral) depending on severity; mediastinal and affected lung; reduced chest- affected lung sounds over affected lung
tracheal deviation away from affected lung, wall expansion over involved
varying with severity lung
Pleural effusion Increased ventilatory rate (respiratory Absent tactile fremitus over Dull percussion note Absent breath sounds over affected
Appendix 1

(unilateral) distress) and cyanosis varying with severity; affected area; decreased over affected area region
mediastinal and tracheal shift away from chest-wall expansion on
affected side based on severity (size of the affected side
effusion)

The actual clinical manifestations and physical examination findings will vary with the severity of the presentation.
*
445
 APPENDIX 2

Quick Reference Material—

Spirogram, ECG, Pulmonary Artery
Catheter, and Capnography

Spirogram showing lung volumes and capacities 447

Normal Lead II ECG tracing 448
Normal pulmonary artery catheter pressure tracings during
catheter insertion 449
Pressure-time waveforms representing various modes of
mechanical ventilation 450–451
Capnography tracings 452
 1. Spirogram showing lung volumes and capacities

Inspiratory
IRV Reserve Volume

Total Lung Capacity

IC Inspiratory
Capacity
VC
Resting
TLC TV Tidal
Volume Vital
Capacity
Expiratory
ERV
Functional Reserve Volume
FRC Residual
RV RV Capacity Residual
Volume

Appendix 2 447
2. Normal Lead II ECG tracing showing electrophysiologic events (numbers) and electrocardiographic representa-
tion (letters)

T
P
Q RS U

2 8
3 7
6

1 4 5

Sequential electrical events of the cardiac cycle Electrocardiographic representation

1. Impulse from the sinus node Not visible

2. Depolarization of the atria P wave
3. Depolarization of the AV node Isoelectric
4. Repolarization of the atria Usually obscured by the QRS complex
5. Depolarization of the ventricles QRS complex
a. intraventricular septum a. initial portion
b. right and left ventricles b. central and terminal portions
6. Activated state of the ventricles immediately ST segment; isoelectric
after depolarization
7. Repolarization of the ventricles T wave
8. After-potentials following repolarization U wave
of the ventricles

448 Appendix 2
3. Normal pulmonary artery (Swan-Ganz) catheter pressure tracings during catheter insertion

Pulmonary Pulmonary
Right Atrium Right Ventricle Artery Artery “Wedge”

Pulmonary
Artery
Catheter
location

Normal 2-6 torr 30/0 torr 30/15 torr 4-12 torr

values

40

30
mmHg

20
Normal
Waveform 10

0
Time

Appendix 2 449
Pressure-time waveforms representing various modes of mechanical ventilation

A.
Mandatory breath
+

PRESSURE
(cm H2O)
0
I E
–

TIME (sec)

B.
Assisted breath
+
PRESSURE
(cm H2O)

0
I E Subambient (negative)
– pressure generated by patient
triggering assisted breath

TIME (sec)

C.

Assisted breath Mandatory (controlled) breath

+
PRESSURE
(cm H2O)

0
I E I E Subambient (negative)
– pressure generated by patient
triggering assisted breath

TIME (sec)

D.
Mandatory Spontaneous
breath ventilations
+
PRESSURE

Stacked
(cm H2O)

breath
0
I E I E I E I E
–

TIME (sec)

450 Appendix 2
E. SYNCHRONIZED INTERMITTENT MANDATORY
VENTILATION (SIMV)
Mandatory Breaths
Spontaneous Ventilations
+

PRESSURE
(cm H2O)
0
I E I E I E I E
–

TIME (sec)

F. PRESSURE CONTROL VENTILATION (PCV)

Mandatory Breaths
+
PRESSURE
(cm H2O)

0
I E I E
–

TIME (sec)

G. PRESSURE SUPPORT VENTILATION (PSV)

Patient Triggered Breaths (patient determines VT & f)
+
PRESSURE
(cm H2O)

0
I E I E Subambient (negative) Pressure
Generated By Patient
–

TIME (sec)

Appendix 2 451
Capnography tracings

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0

Alveolar plateau cleft, signifying partial recovery from neuromuscular blockade.

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0

Abrupt, transient increase in end-tidal CO2, reflecting an acute rise in CO2 delivery to the pul-
monary vasculature.

POTENTIAL INTERPRETATIONS:
• bicarbonate (HCO 3̄ ) administration
• release of limb tourniquet

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0

Abrupt baseline elevation, signaling a contaminated sample cell requiring cleaning and recalibration.

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0

Progressive drop in end-tidal CO2, suggesting a decreasing V̇CO2 or a decreasing pulmonary

perfusion.

POTENTIAL INTERPRETATIONS:
• hypovolemia
• decreasing cardiac output
• hypoperfusion
• hypothermia

452 Appendix 2
 APPENDIX 3

Quick Reference Material—Mechanical

Ventilation Waveforms

Pressure time waveforms 454

Capnography Tracings 455
Pressure-time waveforms representing various modes
of mechanical ventilation 457
Mean airway pressure 459
Flow-time waveforms 459
Pressure, volume, and flow waveforms demonstrating
controlled mechanical ventilation 460
Pressure, volume, and flow waveforms showing SIMV with PSV and PEEP 461
Pressure, volume, and flow waveforms showing SIMV with PSV 462
Pressure, volume, and flow waveforms depicting pressure
control ventilation (PCV) 463
Pressure, volume, and flow waveforms depicting assist/control ventilation 464
Pressure, volume, and flow waveforms illustrating SIMV 465
Pressure-volume loop 466
Mechanical Ventilator Characteristics 466
Pressure time waveforms

Peak Inspiratory Pressure

Inspiratory Pause

Plateau Pressure

Pressure

Inspiration Expiration

Time

PIP – Pplat = pressure generated to overcome Raw

Peak Inspiratory
Pressure (PIP)
40

30
VT
Cdyn =
Pressure (cm H2O)

PIP – PEEP
20

VT
10 Plateau Pressure Cstatic =
Pplat – PEEP
(Pplat)
0
Inspiration Expiration

Time

454 Appendix 3
Capnography Tracings

CO2 Waveform A–B: Exhalation of CO2-free gas from dead

space
D
38 B–C: Combination of dead space and alveolar
C
gas
C–D: Exhalation of mostly alveolar gas (alveolar
plateau)
E D: “End-tidal” point—CO2 exhalation at
A B
maximum point
Time

D–E: Inhalation of CO2 free gas

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0
Normal, fast-speed CO2 waveform highlighting tracing components.
Abrupt end-tidal CO2 decrease to 0 torr or near 0 torr, reflecting the potential loss of ventilation.

POTENTIAL INTERPRETATIONS:
• esophageal intubation
• ventilator disconnection
• ventilator malfunction
• obstructed or kinked ET tube
Exponential decrease in end-tidal CO2, signifying

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0

interrupted blood flow.

POTENTIAL INTERPRETATIONS:
• cardiac arrest with continued alveolar ventilation
• hypotensive episode (hemorrhage)
• pulmonary embolism
• cardiopulmonary bypass (continues)

Appendix 3 455
(continued)

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0

Progressively increasing end-tidal CO2.

POTENTIAL INTERPRETATIONS:
• hypoventilation
• increasing body temperature
• partial airway obstruction
• absorption of CO2 from exogenous source (e.g., laparoscopy)

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0

Consistently low end-tidal CO2, characterized by a well-defined alveolar plateau indicating a widened P(a-
A) CO2 gradient.

POTENTIAL INTERPRETATIONS:
• hyperventilation
• COPD (pulmonary emphysema, chronic bronchitis)
• asthma
• pulmonary embolism
• hypovolemia

CO2 Waveform CO2 Trend 30 Minutes

76 76

38 38

0 0
Abrupt fall in end-tidal CO2, but not to 0 torr—indicating incomplete sampling of the patient’s expirate.

POTENTIAL INTERPRETATIONS:
• ventilator circuit leak
• partial ventilation circuit disconnection
• retained secretions causing partial airway obstruction
• ET tube in hypopharynx

456 Appendix 3
Pressure-time waveforms representing various modes of mechanical ventilation

A. CONTROLLED MECHANICAL VENTILATION

Mandatory breath
+

PRESSURE
(cm H2O)
0
I E
–

TIME (sec)

B. ASSISTED MECHANICAL VENTILATION

Assisted breath
+
PRESSURE
(cm H2O)

0
I E Subambient (negative)
– pressure generated by patient
triggering assisted breath

TIME (sec)

C. ASSIST/CONTROL MECHANICAL VENTILATION

Assisted breath Mandatory (controlled) breath

+
PRESSURE
(cm H2O)

0
I E I E Subambient (negative)
– pressure generated by patient
triggering assisted breath

TIME (sec)

D. INTERMITTENT MANDATORY VENTILATION (IMV)

Mandatory Spontaneous
breath ventilations
+
PRESSURE

Stacked
(cm H2O)

breath
0
I E I E I E I E
–

TIME (sec)
(continues)

Appendix 3 457
(continued)

E. SYNCHRONIZED INTERMITTENT MANDATORY

VENTILATION (SIMV)
Mandatory Breaths
Spontaneous Ventilations
+

PRESSURE
(cm H2O)
0
I E I E I E I E
–

TIME (sec)

F. PRESSURE CONTROL VENTILATION (PCV)

Mandatory Breaths
+
PRESSURE
(cm H2O)

0
I E I E
–

TIME (sec)

G. PRESSURE SUPPORT VENTILATION (PSV)

Patient Triggered Breaths (patient determines VT & f)
+
PRESSURE
(cm H2O)

0
I E I E Subambient (negative) Pres
Generated By Patient
–

TIME (sec)

458 Appendix 3
Mean airway pressure
50 50

Pressure (cm H2O)

Pressure (cm H2O)

25
25

w
Pa

Pa
Paw 0
0 1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
Time (seconds)
Time (seconds)

The slashed lines within the pressure-time tracing repre-

The slashed lines within the pressure-time tracing repre- sent the mean airway pressure (P̄ AW) in the presence of
sent the mean airway pressure (P̄ AW) in the presence of PEEP. The area under the curve divided by the total cy-
PEEP. The area under the curve divided by the total cy- cle time equals the P̄AW.
cle time equals the P̄AW.

Flow-time waveforms

100
Flow (L/min.)

50

0
1 2 3 4 5 6 7 8 9 10 100

Time (seconds)
Flow (L /min.)

50
Square flow-time waveform.
100
0
Flow (L /min.)

1 2 3 4 5 6 7 8 9 10

50 Time (seconds)

Decelerating flow-time waveform.

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

Sinusoidal flow-time waveform.

Appendix 3 459
Pressure, volume, and flow waveforms demonstrating controlled mechanical ventilation.

Pressure (cm H2O) 25

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)
Volume (L)

0.5

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

120
Flow (L /min.)

60

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

460 Appendix 3
Pressure, volume, and flow waveforms showing SIMV with PSV and PEEP.

50

Pressure (cm H2O)

25

PEEP PEEP PEEP

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

1.0
Mandatory Breaths
Volume (L)

0.5 Spontaneous Breaths

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

(The spontaneous volume is increased because the

breath is pressure supported.)

100
Flow (L /min.)

50

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

Appendix 3 461
Pressure, volume, and flow waveforms showing SIMV with PSV.

50

Pressure (cm H2O)

25

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

1.0
Mandatory Breaths
Volume (L)

0.5 Spontaneous Breaths

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

(The spontaneous volume is increased because the

breath is pressure supported.)

100
Flow (L /min.)

50

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

462 Appendix 3
Pressure, volume, and flow waveforms depicting pressure control ventilation (PCV).

50

Pressure (cm H2O)

25

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

1.0

0.5
Volume (L)

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

100
Flow (L /min.)

50

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

Appendix 3 463
Pressure, volume, and flow waveforms depicting assist/control ventilation.

50

Pressure (cm H2O)

25

0
1 2 3 4 5 6 7 8 9 10
Time (seconds)

1.0
Volume (L)

0.5

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

120
Flow (L /min.)

60

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

464 Appendix 3
Pressure, volume, and flow waveforms illustrating SIMV.

50

Pressure (cm H2O)

25

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

1.0
Mandatory Breaths

0.5
Volume (L)

Spontaneous Breaths

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

100
Flow (L/min.)

50

0
1 2 3 4 5 6 7 8 9 10

Time (seconds)

Appendix 3 465
Pressure-volume loop Cdyn

VT
a
Vi
d
a te
er on
en ti

H
G tila

EX
Volume
p
o en
Lo V
e ure
um s s
ol re

SP
-V e P

IN
e
r ti v
su si
es Po
Pr
PIP

Pressure

Mechanical Ventilator Characteristics

Constant Flow Constant Pressure Variable Flow

Ventilator Ventilator Ventilator
Modes control & SIMV control & SIMV control

Variables Independent Variable Independent Variable Independent Variable

• Flow • Pressure • Volume

Dependent Variable Dependent Variables Dependent Variable

• Pressure • Volume • Pressure
• Flow

Limiting Variable Limiting Variable Limiting Variable

• Volume • Pressure • Volume

Triggering Variables Triggering Variables Triggering Variables

• Time • Time • Time
• Pressure • Pressure • Pressure
• Flow • Flow • Flow

Waveform Analysis • Pressure-time • Pressure-time • Pressure-time

waveform is affected waveform is not waveform is affected
by airway resistence affected by by compliance
changes. compliance and changes.
airway resistence
changes.

• Flow-time • Flow-time • Flow-time

waveform is not waveform is affected waveform is not
affected by by compliance and affected by airway
compliance and airway resistence resistence
airway resistence changes. changes.
changes.

• Volume-time • Volume-time • Volume-time

waveform is not waveform is affected waveform is not
affected by by compliance and affected by
compliance and airway resistence compliance and
airway resistence changes. airway resistence
changes. changes.

466 Appendix 3