The Journal of Emergency Medicine, Vol. -, No. -, pp.

19, 2017
2017 Elsevier Inc. All rights reserved.
0736-4679/$ - see front matter

http://dx.doi.org/10.1016/j.jemermed.2017.04.003

Original
Contributions

MANAGEMENT OF PATIENTS WITH PREDICTED DIFFICULT AIRWAYS IN AN

ACADEMIC EMERGENCY DEPARTMENT

John C. Sakles, MD,* Matthew J. K. Douglas, MD,* Cameron D. Hypes, MD,* Asad E. Patanwala, PHARMD, and
Jarrod M. Mosier, MD*
*Department of Emergency Medicine, Department of Medicine, Section of Pulmonary, Critical Care, Allergy and Sleep, University of Arizona
College of Medicine, Tucson, Arizona, and Department of Pharmacy Practice and Science, University of Arizona College of Pharmacy,
Tucson, Arizona
Reprint Address: John C. Sakles, MD, Department of Emergency Medicine, University of Arizona College of Medicine, 1501 N. Campbell
Avenue, PO Box 245057, Tucson, AZ 85724

, AbstractBackground: Patients with difficult airways tubations. None of these difficult airway patients required
are sometimes encountered in the emergency department rescue with a surgical airway. Conclusions: Difficult airways
(ED), however, there is a little data available regarding their were predicted in 11% of non-arrest patients requiring intu-
management. Objectives: To determine the incidence, man- bation in the ED, the majority of which were managed using
agement, and outcomes of patients with predicted difficult an NMBA and a video laryngoscope with a high first-pass
airways in the ED. Methods: Over the 1-year period from success. 2017 Elsevier Inc. All rights reserved.
July 1, 2015 to June 30, 2016, data were prospectively
collected on all patients intubated in an academic ED. After , Keywordsdifficult airway; airway management;
each intubation, the operator completed an airway manage- tracheal intubation; intubation; video laryngoscopy; emer-
ment data form. Operators performed a pre-intubation gency department
difficult airway assessment and classified patients into
routine, challenging, or difficult airways. All non-arrest pa-
tients were included in the study. Results: There were 456
INTRODUCTION
patients that met inclusion criteria. Fifty (11%) had pre-
dicted difficult airways. In these 50 patients, neuromuscular
blocking agents (NMBAs) were used in 40 (80%), an awake Critically ill patients in the emergency department (ED)
intubation technique with light sedation was used in 7 frequently require tracheal intubation during their resus-
(14%), and no medications were used in 3 (6%). In the 40 citation. Because all of these patients are presumed to
difficult airway patients who underwent NMBA facilitated have a full stomach and are thus at high risk for aspira-
intubation, a video laryngoscope (GlideScope 21, Verathon, tion, neuromuscular blocking agents (NMBA) are
Bothell, WA and C-MAC 19, Karl Storz, Tuttlingen, Ger- typically used, with a rapid sequence intubation (RSI)
many) was used in each of these, with a first-pass success technique (1). More recently, delayed sequence intuba-
of 90%. In the 7 patients who underwent awake intubation, tion (DSI) has been used to optimize preoxygenation in
a video laryngoscope was used in 5, and a flexible fiberoptic
patients at high risk of desaturation (2). Before intubation
scope was used in 2. Ketamine was used in 6 of the awake in-
is attempted, it is common practice to perform a difficult
airway assessment to determine if an NMBA can safely
Disclosures: Dr. Sakles serves as an adviser to Verathon Med- be used (35). If a difficult airway is predicted, it is
ical. generally recommended that an awake intubation be

RECEIVED: 29 March 2017;

ACCEPTED: 5 April 2017

1
2 J. C. Sakles et al.

performed in order to maintain spontaneous ventilation ED intubations are the responsibility of the EM attending,
and avoid a potentially catastrophic cant intubate- and the vast majority are performed by EM residents,
cant oxygenate scenario (47). Surprisingly, there is with an EM attending always at the bedside. In-house
little research on the management of the difficult anesthesia back-up is available 24 h a day.
airway in the ED (8). The purpose of this investigation EM residents receive comprehensive airway training
is to determine the incidence, management and outcomes throughout their residency. During intern orientation
of patients with predicted difficult airways in the ED. there is a 1-day airway laboratory that includes both
didactics and hands-on experience in a simulation labora-
tory with a variety of airway devices. All interns in the
MATERIALS AND METHODS
university-based residency programs rotate on the anes-
Study Design and Setting thesia service for 1 month. Regular didactics on airway
management continue throughout the residency program,
This is a single-center prospective observational study of with ongoing training in both cadaver and simulation lab-
ED intubations performed over the 1-year period from oratories. There is a yearly difficult/failed airway labora-
July 1, 2015 to June 30, 2016, recorded in a continuous tory that all residents are expected to attend. Clinical
quality-improvement database. The study design com- experience with airway management is obtained on rota-
plied with recommendations of the Strengthening the Re- tions in the ED, in the operating room and in the intensive
porting of Observational Studies in Epidemiology care unit.
statement (9). This project received an exemption from
the University of Arizona Institutional Review Board. Selection of Participants
This study was conducted at a 61-bed tertiary care ac-
ademic ED certified by the American College of Sur- This study included all non-arrest patients that underwent
geons as a Level I Trauma Center. There are 36 adult intubation in the ED over the 1-year study period.
beds, 18 pediatric beds, and 7 trauma resuscitation
bays. The annual census is approximately 78,000 visits. Methods and Measurements
The ED has standard airway equipment as well as a
wide array of difficult airway equipment available. There After each ED intubation, a paper-based airway data form
are 12 portable airway rolls containing conventional is completed by the operator. Data collected on the airway
direct laryngoscopes with a variety of straight and curved form include patient, operator, and intubation characteris-
blades. There are three mobile GlideScope units (Vera- tics. This includes data such as patient age, sex and diag-
thon, Bothell, WA) with an assortment of adult hyperan- nosis, operator postgraduate year (PGY) and specialty,
gulated blades (LoPro T3 and LoProT4), standard reason for intubation, method of intubation, drugs used
geometry Macintosh blades (Mac T3 and Mac T4), and for intubation, device used on each attempt, number of
pediatric blades (Cobalt video baton size 1-2 with Cobalt attempts, outcome of each attempt, the presence of
Stat blades size 1 and 2). There are two mobile C-MAC difficult airway characteristics, and the occurrence of
units (Karl Storz, Tuttlingen, Germany) with a variety of any adverse events. Adverse events that are tracked,
standard geometry Macintosh blades (C-MAC Mac 2, 3 and their definitions, have been previously described
and 4) and straight blades (C-MAC Miller 0 and 1). A (10). Residents are taught to perform a rapid, focused,
portable flexible fiberoptic scope (Olympus MAF difficult airway assessment that includes multiple predic-
GM; Olympus, Center Valley, PA) and rigid intubating tors of difficult intubation. Because an airway assessment
optical stylet (Karl Storz Bonfils) are also both avail- has been shown to be challenging to do on many patients
able in the ED. There are three difficult airway carts in in the ED, a list of dichotomous variables is used to assess
the ED, which are stocked with tracheal tube introducers anatomic airway difficulty (11,12). These include airway
(bougies), LMA Fastrachs (size 3, 4 and 5; Teleflex edema, blood in the airway, cervical immobility, facial/
Medical Europe, Ltd, Westmeath, Ireland) and a surgical neck trauma, large tongue, obesity, restricted mouth
airway kit (Cook Universal Cricothyrotomy Catheter opening, short neck, small mandible, and vomit in the
Set; Cook Medical Europe Ltd, Limerick, Ireland). airway. After the difficult airway evaluation is
The ED is staffed full time by 65 board-eligible/board- completed, operators make a pre-intubation assessment
certified emergency physicians who serve as faculty for a of airway difficulty and categorize the patient into one
university-based 3-year emergency medicine (EM) resi- of three categories: routine airway, challenging airway,
dency program, a community-based 3-year EM residency or difficult airway. We did not specify the definition of
program, and a university-based 5-year combined EM/ each of these airway categories, as this is a subjective
pediatrics residency program. There are a total of 78 evaluation by the operator and can vary with patient,
residents in the combined EM training programs. All operator, and clinical circumstances.
Difficult Airway Management in the ED 3

For the purposes of this study, the following methods of Primary Data Analysis
intubation were defined. If an NMBA was used for intuba-
tion, this was considered an NMBA facilitated intubation All results are reported descriptively as proportions. The
(NMBA). This included both RSI and DSI (2,13). If no only continuous variable was age, which was reported as
NMBA was used, this was considered a non-NMBA the mean with standard deviation.
facilitated intubation (No NMBA). If only a sedative
agent was used for intubation, at a full induction dose, RESULTS
this was considered a deep sedation intubation (DEEP
Incidence and Assessment of Difficult Airways
SED). If a sub-induction dose of a sedative agent was
used in conjunction with a topical anesthetic agent for
A total of 526 intubations were performed in the ED over
intubation, this was considered an awake intubation
the 1-year study period. Seventy patients were excluded
(AWAKE). If patients were unresponsive and no drugs
because they were in cardiac arrest. This left 456 patients
were used, these patients were classified as no
in the study group. Of these, operators classified 237
medication intubations (NO MEDS).
(52.0%) as a routine airway, 169 (37.1%) as a challenging
The senior investigator reviewed all airway data
airway, and 50 (11.0%) as a difficult airway (Figure 1).
forms and cross-referenced them with a query of the
The baseline clinical characteristics of these three cohorts
electronic medical record. Any missing or incomplete
are summarized in Table 1.
forms were given to the operator for completion. This
resulted in 100% compliance with the airway
data forms. The data from the paper forms were Management of Difficult Airways
entered into Excel for Windows 2013 (Microsoft,
Redmond, WA) and then transferred and coded into Of the 50 patients in the difficult airway cohort, 80%
STATA 13 (StataCorp, College Station, TX) for (n = 40) underwent NMBA facilitated intubation. When
statistical analysis. an NMBA was used, an RSI technique was used in 85%

456
Non-arrest
ED Intuba ons

Rou ne Challenging Dicult

237/456 169/456 50/456
52.0% 37.1% 11.0%

NMBA No NMBA NMBA No NMBA NMBA No NMBA

234/237 3/237 160/169 9/169 40/50 10/50
98.7% 1.3% 94.7% 5.3% 80.0% 20.0%

2 Deep Sed 4 Deep Sed 0 Deep Sed

1 No Meds 5 No Meds 3 No Meds

RSI DSI Awake RSI DSI Awake RSI DSI Awake

233/234 1/234 0 158/160 2/160 0 34/40 6/40 7/10
99.6% 0.4% 0% 98.8% 1.2% 0% 85.0% 15.0% 70.0%
%
Figure 1. Flow diagram of patients in the study. ED = emergency department; RSI = rapid sequence intubation; DSI = delayed
sequence intubation; Awake = awake intubation; Deep Sed = deep sedation; No Meds = no medications used;
NMBA = neuromuscular blocking agent.
4 J. C. Sakles et al.

(34/40) and a DSI technique was used in 15% (6/40). A used, the first-pass success was 90% (36/40). When an
video laryngoscope was used in all patients who under- awake technique was used, the first-pass success was 57%
went RSI or DSI (GlideScope 21, C-MAC 19). Succinyl- (4/7). Most patients (90%, 45/50) were intubated within
choline was the most common NMBA used (75%; 30/40), two attempts, all were intubated within 4 attempts and
and etomidate was the most common sedative used (78%; none required a surgical airway. Adverse events occurred
31/40) (Table 2). In the 26 trauma patients in the difficult in 40% (28/50) of patients in the difficult airway cohort,
airway cohort, 89% (n = 23) underwent NMBA with hypoxemia being the most commonly reported adverse
facilitated intubation (RSI 22 and DSI 1). Three patients event (28%; 14/50) (Table 4). There were three difficult
underwent intubation with no drugs. No patient under- airway patients that suffered a peri-intubation arrest, none
went awake intubation. In the 24 patients with medical of which were due to a failed airway.
conditions in the difficult airway cohort, 71% (n = 17) un-
derwent NMBA facilitated intubation (RSI 12 and DSI 5) DISCUSSION
and 29% (n = 7) underwent awake intubation.
An awake technique was used in 14% (7/50) of pa- The difficult airway, though in principle understood by all
tients in the difficult airway cohort. A video laryngoscope airway managers, is, in reality, a complex concept that is
(GlideScope 1, C-MAC 4) was used in 5 and a flexible based on the interplay of many different factors. The
fiberoptic scope was used in 2. The most common seda- American Society of Anesthesiologists cites the
tive agent used for awake intubation in the difficult following factors that can contribute to difficult airway
airway cohort was ketamine (86%; 6/7) (Table 3). management: difficulty with patient cooperation, diffi-
Almost all the patients in the difficult airway cohort were culty with face mask ventilation, difficulty with supra-
managed by an EM resident (94%; 47/50). Senior EM res- glottic device placement, difficulty with laryngoscopy,
idents at the PGY 3, 4, or 5 level managed roughly half of difficulty with intubation, and difficulty with surgical
the difficult airway patients (52%; 26/50) (Table 2). airway access (4). Contextual aspects of difficult airway
management have also been described (14). Many guide-
Outcomes of Difficult Airways lines suggest that when a difficult airway is anticipated,
an awake intubation should be performed (4,5,7).
The first-pass success in the entire difficult airway cohort Traditionally, this has been accomplished with a
was 82% (41/50). When an RSI or DSI technique was flexible fiberoptic scope (15).

Table 1. Clinical Characteristics of Patients by Airway Classification

Airway Classification

Routine Airway Challenging Airway Difficult Airway

n = 237 n = 169 n = 50

Age
Years, mean (6SD) 47 (624) 44 (621) 49 (623)
Sex
Male 150 (63.3%) 110 (65.1%) 34 (68.0%)
Medical/trauma
Trauma 51 (21.5%) 68 (40.2%) 26 (52.0%)
Specific anatomic difficult airway
characteristics
Airway edema 2 (0.8%) 4 (2.4%) 7 (14.0%)
Blood in airway 17 (7.2%) 44 (26.0%) 16 (32.0%)
Cervical immobility 45 (19.0%) 62 (36.7%) 20 (40.0%)
Facial/neck trauma 11 (4.6%) 28 (16.6%) 20 (40.0%)
Large tongue 11 (4.6%) 31 (18.3%) 16 (32.0%)
Obesity 28 (11.8%) 46 (27.2%) 18 (36.0%)
Restricted mouth opening 7 (3.0%) 17 (10.1%) 8 (16.0%)
Short neck 16 (6.8%) 36 (21.3%) 11 (22.0%)
Small mandible 14 (5.9%) 26 (15.4%) 9 (18.0%)
Vomit in airway 14 (5.9%) 27 (16.0%) 12 (24.0%)
Other 1 (0.4%) 8 (4.7%) 11 (22.0%)
Number of anatomic difficult airway
characteristics
0 129 (54.4%) 24 (14.2%) 1 (2.0%)
1 68 (28.7%) 49 (29.0%) 11 (22.0%)
2 26 (11.0%) 39 (23.0%) 11 (22.0%)
$3 14 (5.9%) 57 (33.7%) 27 (54.0%)
Difficult Airway Management in the ED 5

Table 2. Method of Intubation, Drugs, Devices and Initial Operators by Airway Classification

Airway Classification

Routine Airway Challenging Airway Difficult Airway

n = 237 n = 169 n = 50

Method of intubation
NMBA (RSI or DSI) 234 (98.7%) 160 (94.7%) 40 (80.0%)
Awake (Light Sedation) 0 0 7 (14.0%)
Sedative (Deep Sedation) 2 (0.8%) 4 (2.4%) 0
No meds (No drugs used) 1 (0.4%) 5 (3.0%) 3 (6.0%)
Drugs Used
NMBA
Succinylcholine 151 (63.7%) 100 (59.2%) 30 (60.0%)
Rocuronium 83 (35.0%) 60 (36.7%) 10 (20.0%)
None 3 (1.3%) 9 (5.3%) 10 (20.0%)
Sedative
Etomidate 205 (86.5%) 134 (79.3%) 31 (62.0%)
Ketamine 14 (5.9%) 19 (11.2%) 15 (30.0%)
Midazolam 9 (3.8%) 7 (4.1%) 1 (2.0%)
Propofol 7 (3.0%) 3 (1.8%) 0
None 2 (0.8%) 6 (3.6%) 3 (6.0%)
Initial device used
Direct laryngoscope 26 (11.0%) 12 (7.1%) 0
GlideScope video laryngoscope 87 (36.7%) 84 (49.7%) 23 (46.0%)
C-MAC video laryngoscope 124 (52.3%) 73 (43.2%) 25 (50.0%)
Flexible fiberoptic scope 0 0 2 (4.0%)
Initial operator specialty
Emergency medicine resident 223 (94.1%) 162 (95.9%) 47 (94.0%)
Emergency medicine attending 1 (0.4%) 0 1 (2.0%)
Anesthesia attending 0 0 1 (2.0%)
Other* 13 (5.5%) 7 (4.1%) 1 (2.0%)
Initial operator PGY
PGY-1 49 (20.7%) 30 (17.8%) 6 (12.0%)
PGY-2 98 (41.4%) 64 (37.9%) 16 (32.0%)
PGY-3, 4, 5 83 (35.0%) 73 (43.2%) 26 (52.0%)
Attending (0.4%) 0 2 (4.0%)
Other 6 (2.5%) 2 (1.2%) 0

NMBA = neuromuscular blocking agent; RSI = rapid sequence intubation; DSI = delayed sequence intubation; PGY = postgraduate year.
* Other = Non-EM/non-anesthesia physician.
Other = Medical student or paramedic student.

In this study we sought to determine the incidence of difficulty. Second, difficult anatomic characteristics
the predicted difficult airway in the ED and how opera- are only one component of the difficult airway
tors chose to manage these. We found that operators pre- assessment (4). Other important considerations are the
dicted a difficult airway in 11% of non-arrest patients assessment of the likelihood that rescue oxygenation
requiring intubation in the ED. Interestingly, the major- will be successful with face-mask ventilation, supra-
ity of these patients underwent an NMBA facilitated glottic device ventilation, or if necessary, by performing
intubation using an RSI or DSI technique. While this a surgical airway. If an operator thinks that rescue
might seem somewhat surprising and contrary to recom- oxygenation is likely to be successful, they may have
mended guidelines, there are several explanations why feel that RSI/DSI is still the best approach to achieve
operators might have chosen to use a NMBA despite tracheal intubation, knowing that they have a safe
the prediction of a difficult airway. First, the traditional back-up plan for oxygenation. Third, although awake
predictors for an anatomically difficult airway are based intubation may be an appropriate technique in
on the use of the direct laryngoscope for intubation. controlled settings, in the ED it may not be practical
When using a video laryngoscope, many of or safe due to a multitude of issues. For example, pa-
these anatomic predictors are probably not as relevant tients requiring intubation in the ED frequently have
(1620). Thus, if an operator has access to a video altered mental status and may be agitated due to head
laryngoscope and is skilled with its use, they might trauma, intoxicants, or hypoxemia. An awake intubation
think that intubation is likely to be successful despite in uncooperative patients is often not possible and may
the presence of traditional anatomic predictors of be more dangerous than performing a NMBA facilitated
6 J. C. Sakles et al.

Table 3. Outcomes by Airway Classification

Airway Classification

Routine Airway Challenging Airway Difficult Airway

n = 237 n = 169 n = 50

Success
First pass success 224 (94.5%) 143 (84.6%) 41 (82.0%)
Success within 2 attempts 232 (97.9%) 161 (95.3%) 45 (90.0%)
Success within 3 attempts 235 (99.2%) 166 (98.2%) 49 (98.0%)
Overall success 237 (100%) 169 (100%) 50 (100%)
Number of adverse events
0 210 (86.6%) 132 (78.1%) 30 (60.0%)
1 22 (9.3%) 32 (18.9%) 14 (28.0%)
2 5 (2.1%) 4 (2.4%) 4 (8.0%)
$3 0 1 (0.6%) 2 (4.0%)
Specific adverse events
Hypoxemia 13 (5.5%) 25 (14.8%) 14 (28.0%)
Hypotension 8 (3.4%) 7 (4.1%) 2 (4.0%)
Dysrhythmia 0 0 1 (2.0%)
Aspiration 3 (1.3%) 2 (1.2%) 0
Esophageal intubation 1 (0.4%) 2 (1.2%) 3 (6.0%)
Peri-intubation arrest 1 (0.4%) 1 (0.6%) 3 (6.0%)
Number of operators
1 232 (97.9%) 155 (91.7%) 42 (84.0%)
2 4 (1.7%) 13 (7.7%) 7 (14.0%)
3 0 1 (0.6%) 1 (2.0%)
4 1 (0.4%) 0 0
Rescue operators
Emergency medicine resident 2 (0.8%) 5 (3.0%) 3 (6.0%)
Emergency medicine attending 3 (1.3%) 8 (4.7%) 5 (10.0%)
Pulmonary fellow 0 0 1 (2.0%)
Number of devices used
1 232 (97.9%) 165 (97.6%) 46 (92.0%)
2 5 (2.1%) 3 (1.8%) 2 (4.0%)
3 0 0 2 (4.0%)
4 0 1 (0.6%) 0

intubation. Fourth, emergency physicians have consid- Limitations

erable experience with RSI, as it is the most common
technique to achieve airway control in the ED (1,21). There are several important limitations to this study. One
In contrast, most emergency physicians have limited limitation is that all the data collected in the study were
experience with awake intubation techniques, documented on the airway form by the operator perform-
particularly flexible fiberoptic intubation. Thus, when ing the intubation. Thus, the data are subject to operator
faced with a difficult airway, operators may feel that bias with potential for under- or over-reporting, which
using a technique with which they are very familiar has been well documented (24,25). Kerrey et al. used
and skilled at is the best option for safely achieving video review of ED intubations and compared this
intubation. information with what was documented in the medical
There is little research available on difficult airway record (24). They found that first-pass success was
management in the ED with which to compare our re- over-reported by 612% in the medical record compared
sults. Soyuncu et al. performed a 2-year prospective with what was seen on video review. Additionally, oxy-
observational study and found a 23.5% incidence of the gen desaturation was observed to occur in 33% of patients
difficult airway, which was defined as a failed first intuba- on video review, but in the medical record was docu-
tion attempt (22). In a multicenter study of 4034 patients mented to have occurred in only 19%. Cemalovic et al.
by Hagiwara et al., a difficult airway was retrospectively used trained observers to document various elements of
defined as two or more attempts (23). They found that us- intubation in the ED and compared this information
ing this definition, a difficult airway was encountered in with the perception of the operators (25). They found
5.4% of patients intubated with a direct laryngoscope that operators perceived desaturation to have occurred
and 7.4% of patients intubated with a video laryngoscope in 13% of patients, but an observer recorded a desatura-
(23). Though the methodology of these studies is not tion event in 23%. Therefore, our data probably suffers
directly comparable to our study, the incidence of diffi- from some degree of under- or over-reporting, with the
cult airways we observed was in this range. first-pass success likely higher and the adverse events
Difficult Airway Management in the ED 7

Table 4. Assessment, Management and Outcomes in difficulties and did not collect information on other as-
Difficult Airway Cohort by Method of Intubation
pects of difficult airway management such as potential
NMBA Awake difficulty with rescue oxygenation, including difficult
Group Group face-mask ventilation, difficult supraglottic device venti-
n = 40 n=7 lation, and difficult surgical airway access. These assess-
Assessment ments are likely to contribute to airway management
Specific anatomic difficult decisions, in particular, if an NMBA can be safely used
airway characteristics to facilitate intubation. For example, even if an anatomi-
Airway edema 6 (15.0%) 1 (14.3%)
Blood in airway 14 (35.0%) 0 cally difficult airway is predicted, the operator might feel
Cervical immobility 18 (45.0%) 1 (14.3%) that RSI/DSI is still a safe choice if rescue oxygenation
Facial/neck trauma 19 (47.5%) 0 with face-mask ventilation is predicted not to be difficult.
Large tongue 11 (27.5%) 5 (71.4%)
Obesity 13 (32.5%) 5 (71.4%) Another limitation is that we did not provide specific def-
Restricted mouth opening 6 (15.0%) 1 (14.3%) initions of the three different airway classifications on the
Short neck 7 (17.5%) 4 (57.1%) airway data form. Instead we relied solely on the opera-
Small mandible 7 (17.5%) 2 (28.6%)
Vomit in airway 10 (25.0%) 0 tors assessment after their airway evaluation. A final lim-
Other* 7 (17.5%) 3 (42.9%) itation is that the vast majority of intubations in this study
Number of anatomic difficult were managed by residents in EM and thus might not
airway characteristics
0 1 (2.5%) 0 reflect actual clinical practice by seasoned clinicians in
1 9 (22.5%) 1 (14.3%) non-academic medical centers. Additionally, the EM res-
2 9 (22.5%) 2 (28.6%) idents in this program receive extensive training and have
$3 21 (52.5%) 4 (57.1%)
Management a great deal of clinical experience with both hyperangu-
Drugs used lated and standard geometry video laryngoscopes, and
NMBA thus, the results might be applicable to operators with
Succinylcholine 30 (75.0%) NA
Rocuronium 10 (25.0%) NA less video laryngoscopy experience.
Sedative
Etomidate 31 (77.5%) 0 CONCLUSION
Ketamine 8 (20.0%) 6 (85.7%)
Midazolam 0 1 (14.3%)
None 1 (2.5%) 0 In this study we found that a difficult airway was pre-
Initial device used dicted in 11% of non-arrest patients requiring intubation
Direct laryngoscope 0 0
GlideScope video laryngoscope 21 (52.5%) 1 (14.3%) in a large urban academic ED. The majority of these pa-
C-MAC video laryngoscope 19 (47.5%) 4 (57.1%) tients were managed with an RSI or DSI technique and a
Flexible fiberoptic laryngoscope 0 2 (28.6%) video laryngoscope, with a high first-pass success.
Outcomes
Success A small number underwent an awake intubation, which
First pass success 36 (90.0%) 4 (57.1%) was most commonly performed with a video laryngo-
Success within 2 attempts 39 (97.5%) 5 (71.4%) scope and ketamine. A flexible fiberoptic scope was
Success within 3 attempts 39 (97.5%) 7 (100%)
Success within 4 attempts 40 (100%) - rarely used. There were no failed airways requiring
Specific adverse events rescue with a surgical airway. Further research is
Hypoxemia 12 (30.0%) 2 (28.6%) warranted on the optimal management of patients with
Hypotension 2 (5.0%) 0
Dysrhythmia 0 1 (14.3%) difficult airways requiring intubation in the ED.
Aspiration 0 0
Esophageal intubation 2 (5.0%) 0
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Difficult Airway Management in the ED 9

ARTICLE SUMMARY
1. Why is this topic important?
Patients requiring airway management in the emer-
gency department (ED) occasionally may have difficult
airways, and the current management of these patients
is unknown.
2. What does this study attempt to show?
This study attempts to determine the incidence of pre-
dicted difficult airways in the ED and to describe how
they were managed.
3. What are the key findings?
One in 10 patients were predicted to have a difficult
airway in the ED. The majority of them were intubated us-
ing a neuromuscular blocking agent and a video laryngo-
scope with a high first-pass success.
4. How is patient care impacted?
Rapid sequence intubation with a video laryngoscope
may be a reasonable management option for patients
with difficult airways in the ED if rescue oxygenation is
predicted to be successful.