Perioperative Medicine

ABSTRACT
Background: Difficult or failed intubation is a major contributor to mor-
bidity for patients and liability for anesthesiologists. Updated difficult airway

Management of Difficult management guidelines and incorporation of new airway devices into practice
may have affected patient outcomes. The authors therefore compared recent

Tracheal Intubation
malpractice claims related to difficult tracheal intubation to older claims using
the Anesthesia Closed Claims Project database.
Methods: Claims with difficult tracheal intubation as the primary damaging
A Closed Claims Analysis event occurring in the years 2000 to 2012 (n = 102) were compared to diffi-
cult tracheal intubation claims from 1993 to 1999 (n = 93). Difficult intubation
Aaron M. Joffe, D.O., Michael F. Aziz, M.D., claims from 2000 to 2012 were evaluated for preoperative predictors and
Karen L. Posner, Ph.D., Laura V. Duggan, M.D., F.R.C.P.C., appropriateness of airway management.
Shawn L. Mincer, M.S.W., Karen B. Domino, M.D., M.P.H.
Results: Patients in 2000 to 2012 difficult intubation claims were sicker
Anesthesiology 2019; 131:818–29 (78% American Society of Anesthesiologists [ASA] Physical Status III to V; n =
78 of 102) and had more emergency procedures (37%; n = 37 of 102) com-
pared to patients in 1993 to 1999 claims (47% ASA Physical Status III to V; n
EDITOR’S PERSPECTIVE = 36 of 93; P < 0.001 and 22% emergency; n = 19 of 93; P = 0.025). More
difficult tracheal intubation events occurred in nonperioperative locations in
What We Already Know about This Topic 2000 to 2012 than 1993 to 1999 (23%; n = 23 of 102 vs. 10%; n = 10 of
93; P = 0.035). Outcomes differed between time periods (P < 0.001), with a
• Difficult or failed intubation is a major contributor to morbidity for
higher proportion of death in 2000 to 2012 claims (73%; n = 74 of 102 vs.
patients and liability for anesthesiologists.
• Updated difficult airway management guidelines and incorpora- 42%; n = 39 of 93 in 1993 to 1999 claims; P < 0.001 adjusted for multiple
tion of new airway devices into practice may have affected patient testing). In 2000 to 2012 claims, preoperative predictors of difficult tracheal
outcomes. intubation were present in 76% (78 of 102). In the 97 claims with sufficient
information for assessment, inappropriate airway management occurred in
What This Article Tells Us That Is New 73% (71 of 97; κ = 0.44 to 0.66). A “can’t intubate, can’t oxygenate” emer-
• This article compared recent malpractice claims related to difficult gency occurred in 80 claims with delayed surgical airway in more than one
tracheal intubation to historic claims using the Anesthesia Closed third (39%; n = 31 of 80).
Claims Project database. Conclusions: Outcomes remained poor in recent malpractice claims
• Outcomes remained poor in recent malpractice claims related to related to difficult tracheal intubation. Inadequate airway planning and judg-
difficult tracheal intubation. The number of claims during the induc- ment errors were contributors to patient harm. Our results emphasize the
tion phase of anesthesia in this report is comparable with the previ- need to improve both practitioner skills and systems response when difficult
ous report of 1993 to 1999, but outcomes are poorer. or failed tracheal intubation is encountered.
• Inadequate airway planning and judgment errors were contributors
to patient harm. Almost three fourths exhibited judgment failures, (ANESTHESIOLOGY 2019; 131:818–29)
which were more common in elective and urgent intubation proce-
dures than emergency tracheal intubations.
• Delay in surgical airway initiation during “can’t intubate, can’t oxy-
and death associated with induction of anesthesia, but not
genate” emergencies remains an issue in airway management.
other phases of anesthesia.1 In contrast, Peterson et al.1 found
that claims before the adoption of the first American Society

D ifficult or failed airway management in anesthesia is a

major contributor to patient morbidity and mortality,
including potentially preventable adverse outcomes such as
of Anesthesiologists (ASA) Difficult Airway Guideline in
19936 showed severe injuries in all phases of anesthesia care.
Since the initial difficult airway guideline was published
airway trauma, brain damage, or death.1–5 A previous closed in 1993, it has been updated twice.7,8 In the nearly 15 yr
claims analysis by Peterson et al.1 of malpractice claims asso- since the Peterson report,1 multiple advanced airway devices,
ciated with adverse difficult intubation events from 1993 to including newer video laryngoscopes and supraglottic air-
1999 found a reduction in patient permanent brain damage way devices, have been introduced and incorporated into

This article has been selected for the Anesthesiology CME Program. Learning objectives and disclosure and ordering information can be found in the CME section at the front of
this issue. This article is accompanied by an editorial on p. 774. Preliminary findings were presented as an abstract (No. 16AP07-5) at the European Society of Anesthesiology
Meeting in Geneva, Switzerland, June 5, 2017.
Submitted for publication September 14, 2018. Accepted for publication April 19, 2019. From the Department of Anesthesiology and Pain Medicine, University of Washington,
Seattle, Washington (A.M.J., K.L.P., S.L.M., K.B.D.); the Department of Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, Oregon (M.F.A.);
and the Department of Anesthesiology, Pharmacology, and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada (L.V.D.).
Copyright © 2019, the American Society of Anesthesiologists, Inc. All Rights Reserved. Anesthesiology 2019; 131:818–29. DOI: 10.1097/ALN.0000000000002815

818 October 2019 ANESTHESIOLOGY, V 131 • NO 4

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 Management of Difficult Tracheal Intubation

clinical practice. A 2018 study of 421,581 anesthetics in a emergency room, intensive care unit (ICU), or hospital
regional community anesthesia practice found the rates of ward. Acute pain management and chronic pain medicine
difficult and failed tracheal intubation decreased fourfold claims were not included in this analysis. Claims associated
between 2002 and 2015.9 From 2011 to 2016, the rates of with difficult intubation of neonates immediately postde-
difficult and failed intubation were 1.6 per 1,000 and 0.06 livery were not included; there were no exclusions based
per 1,000 patients, respectively.9 Brain damage and death on age.
are very rare outcomes of difficult airway management.
The Fourth National Audit Project of the Royal College Definition of Variables
of Anaesthetists (London, United Kingdom) reported that
Claims in which difficult intubation (defined as multiple
brain damage or death occurred once for every 180,000
attempts at tracheal intubation or failed intubation) was
general anesthetics delivered in 2008.5 As malpractice claims
identified as the primary damaging event leading to injury
are useful to study rare adverse events with severe outcomes,
for events that occurred in the years 2000 to 2012 were
we analyzed claims in the Anesthesia Closed Claims Project
classified as “difficult tracheal intubation” claims for com-
database for injuries related to difficult tracheal intuba-
parison to difficult tracheal intubation claims previously
tion in the years 2000 to 2012. We compared patient and
analyzed by Peterson et al.1 Selection criteria for the claims
case characteristics, adverse outcomes, and timing of diffi-
analyzed by Peterson et al.1 were previously reported and
cult airway events in the more recent claims to those from
involved reviewer completion of a supplemental question-
1993 to 1999 in our previous report. We hypothesized that
naire concerning difficult airway management and tracheal
potentially preventable complications occur with difficult
intubation. This supplemental questionnaire was designed
or failed tracheal intubation despite updated practice guide-
to assess the impact of the 1993 difficult airway guidelines
lines and improved airway techniques.
on difficult airway management and was discontinued after
completion of the Peterson study. For the current study,
Materials and Methods only claims for events that occurred in 1993 to 1999 (after
The Anesthesia Closed Claims Project database is a structured adoption of guidelines for difficult airway management
collection of closed anesthesia malpractice claims in the United by the ASA) as analyzed by Peterson et al.1 were included.
States that has previously been described in detail.10 Procedures Claims in the Peterson et al.1 cohort that occurred in the
have been approved by the University of Washington Human years 1985 to 1992 were not included.
Subjects Committee (Seattle, Washington; Institutional Permanent brain damage was defined as brain damage with
Review Board application No. 43939). Data were obtained severity of injury in the permanent and disabling range (e.g., 6
from a panel of malpractice insurers from throughout the to 8 on the severity of injury scale). Airway injury and other
United States and were abstracted from insurance company clinical outcomes (other than permanent brain damage and
files by board-certified practicing anesthesiologists. Data were death) were classified exclusive of permanent brain damage
collected from depositions, medical records, autopsy reports, or death to yield outcomes in four mutually exclusive cate-
expert witness statements, claims manager summaries, con- gories: death, permanent brain damage, airway injury, and all
sultant evaluations, and other legal documents. Data collec- other injuries. Permanent brain damage or death were defined
tion included the type of surgery, details of the anesthesia by the status of the patient at claim resolution. The outcome
care provided, patient demographics, patient outcomes, legal for a patient suffering permanent brain damage in the time
proceedings, and any payments made. The on-site anesthe- period immediately after a difficult tracheal intubation who
siologist reviewer evaluated the type and severity of injury died before claim closure was classified as death in the database.
and the cause of injury (i.e., damaging event). The National The location and phase of care during which difficult
Association of Insurance Commissioners’ (Washington, D.C.) tracheal intubation occurred was classified as in Peterson et
10-point scale, which ranges from 0 (no apparent injury) to al.1: preinduction, induction, intraoperative or intraproce-
9 (death), was used to determine the severity of the injury dure, during extubation in the operating room, or during
to the patient in each claim.11 The on-site anesthesiologist recovery in the postanesthesia recovery unit. These claims
reviewer wrote a narrative summary of the claim, including were grouped as “perioperative” claims. Nonoperating
the sequence of events, potential causes of injury, and addi- room anesthetizing locations were classified as “periopera-
tional details relevant to that claim. On-site reviewer assess- tive” claims as well, with phase of care classified as described
ments were reviewed by the Closed Claims Committee for above. Claims that occurred in locations outside of the
consistency with study classifications. operating room or recovery area where an anesthesiologist
For this study, we used the Closed Claims Project data- was called to assist (rather than providing procedural anes-
base of 11,034 claims collected through December 31, thesia care) were classified as “outside location.”
2016. Inclusion criteria were surgical and procedural anes- For difficult tracheal intubation claims for events that
thesia, obstetric anesthesia, and claims in which the anes- occurred in the years 2000 to 2012, airway management
thesiologist was called for airway management outside of details were abstracted from the claim narratives and clas-
the operating room, e.g., the postanesthesia recovery room, sified by three of the authors (K.B.D., A.M.J., M.F.A.).

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 Perioperative Medicine

Agreement by two of the authors was required for clas- in a similar manner, with both unadjusted and Bonferroni
sification, with disagreements resolved through discussion. adjusted P values reported. Odds ratios were calculated by
Urgency of tracheal intubation was classified as emergency logistic regression. The interaction between study cohort
(intubation is required immediately and without delay), (2000 to 2012 claims vs. 1993 to 1999) and phase of care
urgent (intubation is required, but not immediately), or (induction vs. other phases) on outcomes was analyzed by
elective (no urgency, e.g., purely elective case or airway logistic regression. No statistical power calculation was con-
management). The authors identified potential predictors ducted before the study. The sample size was based on the
of difficult tracheal intubation including past history of available data. All statistical analysis employed IBM SPSS
difficult tracheal intubation, acute airway obstruction from Statistics 25 (International Business Machines Corporation,
any cause, Mallampati grade 3 or 4, limited cervical spine USA).
extension, limited mouth opening, secretions or blood in
the airway, short neck, thick or bull neck, previous neck Results
irradiation, short thyromental distance, swollen tongue,
There were 93 claims related to difficult tracheal intubation
preeclampsia, or prominent teeth if they were noted in
for events that occurred in 1993 to 99 and 102 in 2000 to
the on-site reviewer’s claim narrative. These three authors
12 (2000 to 2005: n = 61; 2006 to 2012: n = 41).
(K.B.D., A.M.J., M.F.A.) also assessed whether the airway
management was appropriate or not, based the 2013 ASA
practice guidelines for management of the difficult airway.8 Comparison of Difficult Tracheal Intubation Claims 2000
Indications of inappropriate management were classified as to 2012 versus 1993 to 1999
inadequate preoperative or airway evaluation, failure to plan Patient and Case Characteristics.  Difficult tracheal intuba-
for difficult intubation at induction, no backup plan for dif- tion claims that occurred in 2000 to 2012 had a higher pro-
ficult reintubation after (failed) extubation, failure to use a portion of ASA Physical Status III to V patients undergoing
supraglottic airway as a bridge for oxygenation during dif- emergency procedures compared to 1993 to 1999 claims
ficult intubation, perseveration, and delay or failure to call (P < 0.001 and P = 0.025, respectively; table 1). The distri-
for a surgical airway in a “can’t intubate, can’t oxygenate” bution of surgical procedures differed (P = 0.045, table 1),
emergency. Perseveration was defined as consistent appli- with higher proportions of orthopedic procedures in 1993
cation of any airway management technique or tool more to 1999 claims (23%) compared to 2000 to 2012 (9%; odds
than twice (i.e., greater than or equal to three attempts) ratio, 3.01 [1.30 to 7.0]; P = 0.008, P = 0.064 adjusted for
without deviation or change of technique, or the return to multiple testing). More difficult tracheal intubation events
a technique or tool that had previously been unsuccessful. occurred in outside locations in 2000 to 12 than in 1993 to
1999 (P = 0.035; table 1).There were no statistically signifi-
Statistical Analysis cant differences in age, sex, or primary anesthetic technique
between the two cohorts (table 1).
Interrater reliability was determined on a sample of 2000 to
2012 difficult airway claims for the individual indications of Phase of Care, Location, and Outcomes of Difficult Tracheal
inappropriate airway management using κ scores. Pairwise Intubation in Perioperative Locations. Difficult intubation
κ scores between the three evaluating authors were calcu- in perioperative locations were similarly distributed across
lated and the mean of the three pairwise scores reported. phases of anesthesia care between the 1993 to 1999 and
Patient and case characteristics, and clinical outcomes for 2000 to 2012 cohorts (P  =  0.808; table  2). Two thirds of
claims occurring in the year 2000 to 2012 were compared difficult intubation events occurred at induction, 13 to 14%
to claims that occurred in 1993 to 1999 using chi-square during the procedure, and 14 to 16% at extubation in the
test, Fisher exact test (when cells had expected counts of operating room. Another 4 to 7% occurred during recovery
less than five), and independent t test for equality of means in the postanesthesia care unit (table 2).
with two-tailed tests and P < 0.05 as the criterion for sta- Outcomes differed between time periods (P < 0.001;
tistical significance. For tables that were larger than 2 × 2 fig. 1). Patients in 2000 to 2012 difficult tracheal intubation
and expected cell counts of less than 5, Fisher exact test was claims were more likely to have suffered death than earlier
performed with Monte Carlo significance calculated using difficult intubation claims (n = 74 [73%] vs. n = 39 [42%]
10,000 sampled tables. In order to minimize the incidence for 1993 to 1999 claims; P < 0.001, P < 0.001 adjusted for
of type 1 error, we only tested individual table components multiple testing). Permanent brain damage was similar in
if the overall distribution in the table was statistically sig- the two time periods. Airway injury was more common
nificant at P < 0.05. For tables large than 2 × 2 where in the earlier claims (n = 32 [34%]; P < 0.001, P < 0001
statistically significant distributions were identified, post hoc adjusted for multiple testing). When both phase of care and
2 × 2 tests on collapsed variables were performed, with time period were included in an analysis of perioperative
both unadjusted and Bonferroni adjusted P values reported. claims, the odds of brain damage or death at induction was
Multiple testing of factors associated with appropriateness 5.5 times greater in 2000 to 2012 compared to 1993 to
of airway management (location and urgency) were handled 1999 (odds ratio, 5.5; 95% CI, 1.07 to 28.4; P = 0.041).

820 Anesthesiology 2019; 131:818–29 Joffe et al.

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 Management of Difficult Tracheal Intubation

Table 1.  Patient and Case Characteristics

1993 to 1999, 2000 to 2012, Odds Ratio

n (% of 93) n (% of 102) (95% CI) P Value

Male 44 (47%) 62 (61%) 1.73 (0.98 to 3.05) 0.063

ASA Physical Status III to V (n = 178) 36 (47%) 78 (76%) 0.277 (0.146 to 0.53) < 0.001
Emergency (n = 187) 19 (22%) 37 (37%) 0.46 (0.241 to 0.89) 0.025
Pediatric 2 (2%) 2 (2%) 1.10 (0.152 to 8.0) 1.000*
Age in yr: mean ± SD 50 ± 17 52 ± 13 2.14 (–2.13 to 6.4) 0.325
Age > 65 yr 17 (18%) 17 (17%) 1.12 (0.53 to 2.34) 0.851
Obese (n = 151) 44 (62%) 54 (68%) 0.79 (0.40 to 1.53) 0.499
Primary anesthetic 0.092*
 General 83 (89%) 82 (80%) 2.02 (0.89 to 4.6)
 Regional 2 (2%) 0 (0%) NA
  Monitored anesthesia care 3 (3%) 8 (8%) 0.392 (0.101 to 1.52)
 None 4 (4%) 11 (11%) 0.372 (0.114 to 1.21)
 Combined general + regional 1 (1%) 1 (1%) 1.10 (0.068 to 17.8)
Procedures 0.042*
  General surgery 24 (26%) 16 (16%) 1.87 (0.92 to 3.79)
 Orthopedics 21 (23%) 9 (9%) 3.01 (1.30 to 7.0)
  Head, neck, ear, nose, and throat 20 (22%) 25 (25%) 0.84 (0.43 to 1.65)
 Vascular/cardiothoracic 10 (11%) 16 (16%) 0.65 (0.278 to 1.51)
 Neurologic/spine 5 (5%) 10 (10%) 0.52 (0.172 to 1.59)
 Cesarean delivery 2 (2%) 3 (3%) 0.73 (0.118 to 4.4)
 Gynecology/urology 6 (6%) 10 (10%) 0.63 (0.221 to 1.82)
 Other† 5 (5%) 13 (13%) 0.389 (0.133 to 1.14)
Location of difficult airway event 0.035
 Perioperative 83 (89%) 79 (77%) 2.42 (1.08 to 5.398)
  Outside location 10 (11%) 23 (23%) 0.41 (0.185 to 0.92)

Total N = 195 unless otherwise indicated. Claims with missing data excluded. Percentages may sum to greater than or less than 100% due to rounding. P values by chi-square or
Fisher exact test for proportions and t test for age. Odds ratios based on 1993 to 1999 as the indicator and 2000 to 2012 as the reference category.
*P values by Fisher exact test with Monte Carlo significance using 10,000 sampled tables. †Other procedures included ventilator management (n = 6), resuscitation (n = 8), place/
change arterial or central venous catheter (n = 2), eye (n = 1), and endoscopy (n = 1).
ASA, American Society of Anesthesiologists; NA, odds ratio undefined.

Table 2.  Timing of Perioperative Difficult Airway Claims and Outcomes

1993 to 1999 (n = 83) 2000 to 2012 (n = 79)

Phase Claims, No. (column %) BD/D, No. (row %) Claims, No. (column %) BD/D, No. (row %)

Preinduction 1 (1%) 1 (100%) 0 0

Induction 52 (63%) 15 (29%) 53 (67%) 40 (75%)
Intraprocedure 12 (14%) 10 (83%) 10 (13%) 7 (70%)
Extubation in OR 12 (14%) 10 (83%) 13 (16%) 12 (92%)
Recovery/PACU 6 (7%) 4 (67%) 3 (4%) 3 (100%)

Perioperative defined as preinduction through recovery in the OR or PACU. P = 0.808 by Fisher exact test for phase by time period. Odds ratio for interaction between phase (excluding
preinduction) and time period on outcome = 5.5 (95% CI, 1.07 to 28.4); P = 0.041. Odds ratio by multiple logistic regression.
BD/D, permanent brain damage or death; OR, operating room; PACU, postanesthesia care unit.

For 2000 to 2012 claims, in all locations except the brain damage or death, most (76%, n = 13) occurred during
operating room, all claims resulted in brain damage or induction of anesthesia (table 2).
death. The operating room was the only location in which
some difficult tracheal intubation claims did not result in Patient Characteristics and Airway Management
permanent brain damage or death (n = 17); brain damage Techniques in 2000 to 2012 Claims
or death was the result for difficult intubation events in all Patient Characteristics and Urgency of Tracheal Intubation.
other locations (n = 33 in ICU, 3 postanesthesia care unit, Patients were obese in two thirds (n  =  54) of the difficult
6 emergency room, 2 ward, 1 cardiac catheterization lab, 1 tracheal intubation claims. Most were adults, with only four
radiology). Of the 17 claims that did not result in permanent obstetric patients (all were obese and two were diagnosed

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 Perioperative Medicine

Table 3.  Predictors of Difficult Tracheal Intubation and

Judgment Failures in Airway Management

Claims,
Question No. %

Indicate any predictors of difficult tracheal intubation

(whether known/recognized at the time or not) or
factors that contributed to difficult airway management.
  Airway obstruction from any cause* 31 30%
  Past history of difficult intubation 21 21%
  Mallampati grade 3 to 4 19 19%
  Limited cervical spine extension 16 16%
  Limited mouth opening 13 13%
Fig. 1.  Clinical outcomes in difficult tracheal intubation claims   Secretions/blood in airway 12 12%
1993 to 1999 versus 2000 to 2012. Airway injury and “all other”   Short neck 10 10%
  Swollen tongue 6 6%
outcomes exclude death or permanent brain damage. P < 0.001
  Short thyromental distance 6 6%
by chi-square test.  Thick or bull neck 6 6%
  History of neck irradiation 5 5%
 Preeclampsia 2 2%
with preeclampsia; all four had difficult tracheal intubation at   Prominent teeth 1 1%
Number of predictors
induction) and two were pediatric patients (age 24 months;  0 24 24%
undergoing cleft lip and palate with difficult reintubation  1 36 35%
during phase 1 recovery and age 16 with posttonsillectomy   2 to 6 42 41%
bleeding with difficult intubation at induction). Inappropriate difficult airway management
  Failure to use supraglottic airway as a bridge (κ = 0.552) 27 26%
Preoperative predictors of a difficult tracheal intubation   Perseveration (κ = 0.489) 25 25%
were present in 76% of difficult tracheal intubation claims   Failure to plan for difficult tracheal intubation 23 23%
(n = 78), with nearly half (n = 42) possessing two or more (induction; κ = 0.627)
predictors of a difficult airway (table 3). The most common   Delayed calling for, or did not call for, a surgical 20 20%
airway (κ = 0.436)
predictors were airway obstruction, past history of difficult   Inadequate preoperative or airway evaluation (κ = 0.664) 17 17%
intubation, Mallampati grade 3 to 4, and limited cervical   No backup plan for difficult reintubation 14 14%
spine extension (table 3). (extubation; κ = 0.664)
More than one third of difficult tracheal intubations Number of judgment failures (n = 97)†
  None of the above (appropriate management) 26 27%
involved elective intubations (36%; n  =  37 of 102), with  1 34 35%
almost all occurring in operating room or nonoperating room   2 to 5 37 38%
anesthetizing locations (97%; n = 36 of 102). Urgent tracheal
Percentages based on n = 102 claims unless otherwise noted.
intubation comprised 20% of claims (n = 20 of 102) and all *Causes of airway obstruction: neck hematoma (n = 13), allergic reaction (n = 4),
occurred in operating room or nonoperating room anesthe- infection (n = 4 [3 neck abscess, 1 acute epiglottis]), other upper airway obstruc-
tizing locations. Emergency tracheal intubation comprised tion (n = 6 [2 pharyngeal mass, 4 miscellaneous upper airway obstruction]), and
infraglottic obstruction (n = 4 [1 tracheal stenosis, 3 tracheal compression from
almost half of the claims (44%; n = 45 of 102) and occurred in goiter]). †Five claims were excluded from the count of judgment problems because
a variety of locations (operating room, n = 20; nonoperating an evaluation of the appropriateness of airway management could not be made.

room anesthetizing locations, n = 1; recovery room, n = 3;

intensive care unit, n = 12; emergency room, n = 6; and other
[ward or nonanesthetizing locations where anesthesia was
or video laryngoscopy while exchanging these tubes. In
called to assist with airway management], n = 3).
one case the initial technique was jet ventilation. The initial
Airway Management Techniques. The most common technique could not be determined in seven claims.
method used for tracheal intubation during initial attempts Subsequent techniques used after the initial intubation
was direct laryngoscopy (n  =  72; 71%). Flexible fiberop- attempt included direct laryngoscopy in 68 cases (67%),
tic intubation was the initial technique attempt in 10 cases supraglottic airway in 38 (37%), flexible fiberoptic in 20
(10%). Other techniques used for initial attempts included (20%), and video laryngoscopy in 9 (9%). Additional tech-
supraglottic airway (n  =  6), video laryngoscopy (n  =  2), niques subsequent to the initial intubation attempt also
and blind nasal intubation (n = 2). The initial technique in included blind nasal (n = 5), retrograde intubation (n = 2),
another two cases involved use of a Cook airway exchanger tube changer (n = 2), rigid laryngoscopy by the otolaryn-
(Cook Medical, USA) to replace a double lumen endotra- gology surgeon (n = 1), and bronchoscopy (unclear if rigid
cheal tube with a single lumen tube or to replace a single or flexible; n = 1).
lumen tube with a double lumen tube. There was no infor- Attempts at awake tracheal intubation occurred, but
mation regarding use of an assistive device such as direct failed, in 11 claims; a flexible fiberoptic scope was used

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 Management of Difficult Tracheal Intubation

in five claims with direct laryngoscopy used in an addi- A surgical airway was performed in 76% of the “can’t
tional five (one unknown technique). Patients were intubate, can’t oxygenate” emergencies (n  =  61 of 80
sedated in seven of these claims and were not sedated claims). Surgical airways in the operating room (n  =  45)
in three (one unknown). Reasons for failed awake intu- were mostly performed by the case surgeon (general, tho-
bation, where known, included no or inadequate topical racic, or vascular, ear-nose-throat, or spine surgeons [60%;
anesthesia (n = 3), airway obstruction during topical anes- n  =  27]). A different surgeon was called to the operating
thesia (n = 1), and oversedation resulting in apnea, airway room to perform a surgical airway in 29% (n = 13). Less
obstruction, and inability to ventilate (n = 5). In 16 claims commonly, anesthesiologists attempted surgical airways
(16%), a supraglottic airway was used as a conduit for intu- (n  =  2; 1 successful, 1 not) in the operating room. In all
bation. Intubation was successful in three of these claims, 61 claims with attempted surgical airways, the surgical air-
and unsuccessful in the remainder. way was difficult to achieve in 28% of the cases (n = 17).
In claims with sufficient information to evaluate (n = 87), Difficulty was attributed to difficult anatomy (n = 8), sub-
a “can’t intubate, can’t oxygenate” emergency occurred in cutaneous emphysema from jet ventilation (n = 4), bleeding
the majority (92%; n = 80).Transtracheal jet ventilation was and other complications from a surgical airway (n = 4), or
used in eight cases with five resulting in barotrauma (sub- surgeon inexperience (n = 1). Complications occurred in
cutaneous emphysema with or without pneumothorax). six surgical airways including tracheal transection, esopha-
Subsequent attempts at surgical airway proved difficult in geal laceration, substantial bleeding, loss of surgical blade in
four of five of these cases due to presence of subcutaneous the trachea, or failure to achieve a surgical airway.
emphysema. One fifth of the claims (n = 21; 21%) had systems issues
Of the 80 claims where a “can’t intubate, can’t oxygen- including lack of assistance and equipment, or lack of sys-
ate” emergency was known to have occurred, obtaining a tematic communication for airway issues. The more com-
surgical airway was delayed in more than one third of the mon equipment issues were lack of a difficult airway cart
cases (n  =  31; 39%). In almost two thirds of these delays, in a suitable location (nine cases with delays to obtain cart)
the delay was due, at least in part, to a delay by the anes- and lack of surgical airway equipment (five cases where lack
thesiologist in calling for a surgical airway (n = 20). Other of timely availability of emergency airway equipment con-
delays in obtaining a surgical airway occurred because the tributed to delays in accomplishing surgical airways during
surgeon was not in the hospital (n = 4), the surgeon failed “can’t intubate, can’t oxygenate” emergencies). In five cases
to respond to pager (n = 1), or the surgeon was reluctant to of difficult reintubation after extubation in the ICU, there
perform a surgical airway (n = 3). had been inadequate communication that intubation in the
In cases where a “can’t intubate, can’t oxygenate” emergency operating room had been difficult.
developed, placement of a supraglottic airway was attempted as Appropriateness of Airway Management. In the 97 difficult
a bridge to oxygenation in 36 claims and not attempted in 26. airway claims with sufficient information for assessment,
There was insufficient information to evaluate in the remain- inappropriate difficult airway management occurred in 73%
ing “can’t intubate, can’t oxygenate” claims. In 23 of the claims (n = 71; κ = 0.44 to 0.66; table 3). Two or more judgment
where placement of a supraglottic airway was attempted, the failures occurred in 38% (n = 37; table 3). Only 27% of claims
“can’t intubate, can’t oxygenate” emergency occurred on (n = 26; table 3) lacked any judgment failures.The most com-
induction of anesthesia; oxygenation with a supraglottic air- mon failures included failure to use a supraglottic airway as a
way was unsuccessful in 19 of these cases. Factors contributing bridge for oxygenation (n = 27; 26% of 102 difficult airway
to lack of successful supraglottic airway oxygenation included claims; κ = 0.55), perseveration (n = 25; 25%; κ = 0.49), and
upper airway obstruction or pathology such as neck abscess or failure to plan for difficult tracheal intubation on induction
previous neck irradiation (n = 5), multiple intubation attempts (n = 23; 23%; κ = 0.63; table 3). Clinical examples of each
before supraglottic airway placement (n = 5), and morbid obe- type of judgment failure are provided in the appendix.
sity (n = 2). In another 3 of the 23 cases where supraglottic In-hospital location of tracheal intubation was not asso-
airway was used as a bridge to oxygenation during induction, ciated with differences in appropriateness of difficult airway
it was successful but too late to prevent hypoxic injury in two management. In the 97 claims in which an evaluation could
cases and hypoxemia due to negative pressure pulmonary be made, perioperative locations (n = 16 of 74 appropri-
edema occurred in the third case. Other cases where supra- ate; 22%) was not significantly different compared to airway
glottic airway was attempted as a bridge during “can’t intubate, management in outside locations (n = 10 of 23 appropri-
can’t oxygenate” emergencies (not during induction) included ate; 43%; P  =  0.039, 0.078 adjusted for multiple testing).
nine cases where difficult tracheal reintubation occurred at Management of difficult tracheal intubation in elective
emergence and three cases during the procedure; oxygenation or urgent circumstances was more frequently judged as
was unsuccessful in all of these cases. In another two cases, inappropriate (84%; n = 46 of 55) in contrast to manage-
supraglottic airway was attempted as a bridge to oxygenation ment during emergency intubation (60%; n  =  25 of 42;
during resuscitation; this was unsuccessful in one case and was P = 0.008, 0.016 adjusted for multiple testing; odds ratio,
successful but delayed in the other. 3.48; 95% CI, 1.35 to 8.9).

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 Perioperative Medicine

Discussion were more common in elective and urgent procedures com-

pared to emergency tracheal intubation procedures. This
Our analysis of difficult tracheal intubation claims in the
result underscores the absence of an airway strategy for
United States highlights several important findings. Claims
elective or urgent cases where the setting may encourage a
for difficult tracheal intubation events in more recent years
false sense of security.
(2000 to 2012) more often involved sicker patients (76%
A lack of adequate planning for intubation difficulty or
ASA III to V) undergoing emergency procedures compared
failure contributed to the injuries in our study. Published
to claims from 1993 to 1999. The proportion of difficult
guidelines recommend an airway strategy (coordinated
tracheal intubation events that occurred in an outside loca-
series of airway plans)5 when predictors of difficulty are
tion in 2000 to 2012 claims was also greater than in the ear-
present.8,16,17 This error was also apparent in claims data
lier claims (23% vs. 11%; P = 0.035). Seventy-six percent of
from Denmark from 1996 to 20042, a Norwegian report
patients in 2000 to 2012 claims had preoperative predictors
spanning a 15-yr period (2001 to 2015),4 and the Fourth
of difficult tracheal intubation. Almost three fourths of 2000
National Audit Project of the Royal College of Anaesthetists
to 2012 claims exhibited judgment failures, including lack
study in the United Kingdom in 2008 to 2009.5
of a proper airway management plan and, during a “can’t
Our study again highlights the considerable risk associ-
intubate, can’t oxygenate” emergency, the failure to utilize a
supraglottic airway as a bridge to oxygenation and delay in ated with the immediate postoperative period. When dif-
attempting a surgical airway. ficult tracheal intubation occurred outside the induction
phase, brain damage or death was common and there was
no improvement in outcomes from 2000 to 2012 com-
Comparison of Difficult Tracheal Intubation Events 1993
pared to 1993 to 1999 (table 2). Only one article regard-
to 1999 versus 2000 to 2012
ing extubation is published for every 36 articles published
Outcomes of difficult tracheal intubation were poor, with a regarding tracheal intubation (Ovid Medline search criteria:
high proportion of death in claims related to difficult intu- airway extubation, intratracheal intubation;Wolters Kluwer;
bation in both time periods. However, claims in 2000 to http://www.ovid/site/catalog/databases/901.jsp, accessed
2012 exhibited an increased proportion of brain damage or May 23, 2018). More research and education should be
death associated with induction of anesthesia compared to focused on this high-risk stage of care, particularly when
claims in 1993 to 1999 (P < 0.001; table 2). The increased difficult tracheal intubation has been encountered, or the
proportion of brain damage or death associated with more nature of the surgery (e.g., procedures around the head and
recent difficult tracheal intubation claims may be related neck, those with fluid shifts, and steep head-down position-
to more high-risk patients, different surgical procedures, ing) may make postextubation airway management more
and/or more emergency care. However, the difference may difficult.
reflect different study methodology in the two time periods Perseveration, defined as the consistent application
with use of a supplemental data collection instrument in the of any airway management technique or tool in three or
early time period, but not in 2000 to 2012 claims. Inclusion more attempts without deviation or change, or the return
criteria differed as 1993 to 1999 cases were not included to a technique or tool that was previously unsuccessful,
if the on-site reviewer did not complete the supplemental was noted in a quarter of 2000 to 2012 claims (table  3).
form. Nonetheless, these findings represent an opportunity Perseveration is a distinct judgment error related to situ-
to re-evaluate the efficacy of our current algorithms and ational awareness and potentially lack of equipment and
training for airway management. the skills to use other devices. Moving along a coordinated
series of plans in an airway strategy also means not dwelling
Clinical Details of Difficult Tracheal Intubation events on techniques already attempted unsuccessfully.
2000 to 2012 Anesthesiologists appeared reluctant to move down
Deficiencies in clinical judgment occurred in the majority the difficult airway algorithm to placement of a surgical
of recent claims (73%; n  =  71 of 97) that could be ade- airway. In cases where enough clinical detail was present
quately assessed in our study. Our study is not unique in this for review, 80 of 102 claims ultimately degenerated into a
finding.5,12–15 In the Danish Anesthesia Database, of emer- “can’t intubate, can’t oxygenate” emergency. In nearly 4 of
gency surgical airway procedures over a 6-yr study period, 10 “can’t intubate, can’t oxygenate” claims, obtaining the
nontechnical skills were judged satisfactory in only 37%.12 surgical airway was delayed due to delay in calling for a
In the Fourth National Audit Project of the Royal College surgical airway, lack of surgeon availability, and delay in per-
of Anaesthetists study, nontechnical skill deficits were iden- forming a surgical airway. Our results stand in contrast to
tified in 40% of cases with one quarter considered to be a current guidelines for management of the “can’t intubate,
major contributor to the poor outcome.5,14 Our findings can’t oxygenate” emergency, which recommend placing a
differ from these reports in that ours studied malpractice supraglottic device while preparing, in parallel, to perform
claims, which would be expected to have more judgment an immediate emergency “surgical airway” should the supra-
errors. However, it is notable that we found judgment errors glottic airway fail to oxygenate the patient.8,16,17

824 Anesthesiology 2019; 131:818–29 Joffe et al.

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 Management of Difficult Tracheal Intubation

A supraglottic airway was not attempted as a bridge difficult airway situations, should be rehearsed on a regular
for oxygenation in 26% of our study (table 4). A supra- basis with the healthcare team, which will aid in focusing
glottic airway can effectively provide rescue oxygenation on technical skills, but also will imbue and maintain ade-
in the management of difficult mask oxygenation and quate crew resource management. Incorporation of cogni-
tracheal intubation.18,19 The Danish Anaesthesia Database tive aids specific to difficult airway management may cue
recently reported that placement of a supraglottic airway practitioners to the need to move on to another plan in
was attempted in only 12.4% of all difficult airway cases.20 their airway strategy while “in the heat of the moment.”
In documented cases of “can’t intubate, can’t oxygenate,” Finally, the education should be malleable so the curric-
reported rates of attempted supraglottic airway place- ula can swiftly incorporate new evidence as it becomes
ment are not much higher, ranging from 18.9 to 35%.20,21 available.
Cognitive aids and team practice in managing the inevi-
table “can’t intubate, can’t oxygenate” emergency may be Limitations
useful.22
Analysis of closed malpractice claims has well-described
Our study also illustrated that poor outcomes after failed
limitations: retrospective analysis, lack of randomization,
tracheal intubation may occur despite adherence to practice
selection, and hindsight bias.10 The database lacks denomi-
guidelines. Awake intubation wasn’t always effective, inser-
nators and cannot estimate risk. Cause-effect relationships
tion of a supraglottic device may not improve oxygenation,
cannot be established. Claims take 3 to 7 yr between event,
and waking a patient up after multiple intubation attempts
claim closure, and incorporation into the database. Hence,
may still yield a poor outcome. Our findings emphasize that
new clinical practices and technologies are not fully cap-
supraglottic airway devices cannot be considered fail-safes
tured. However, our results are relevant for current practice
for the difficult airway in the presence of supra or infraglot-
as Fei et al. reported that the rate of emergency surgical air-
tic obstruction, multiple preceding intubation attempts, and
ways was unchanged from 2008 to 2015 despite increased
previous radiation therapy.
use of video laryngoscopy for tracheal intubation.26
We acknowledge the controversy regarding the best tech-
Data abstraction in 2000 to 2012 claims relied on nar-
nique to establish a surgical airway during a “can’t intubate,
ratives by reviewers using primary data sources at liability
can’t oxygenate” emergency that will achieve both high-
insurers, which may result in missing information. However,
est first-pass success and least amount of patient harm.23
reliability of assessments was acceptable (moderate to sub-
Traditionally, transtracheal jet ventilation has been recom-
stantial: 0.436 to 0.664). κ values were derived from pair-
mended as a bridge to a definitive surgical airway. However,
wise assessments; evaluation of each claim by three authors
a recent systematic review found transtracheal jet ventilation
to derive the final assessment improved reliability above the
in “can’t intubate, can’t oxygenate” was associated with a 32%
measured kappa values. With an overall failed intubation
incidence of barotrauma, 42% incidence of device failure,
incidence of 1.3 events of 10,000 patient encounters,9 dif-
and, in several cases, subsequent difficulty with open surgi-
ficulty in conducting prospective randomized trials study-
cal airway attempts due to obliterated anatomy.24 Our study
ing these high-impact low frequency events is self-evident.9
further supports that attempts at transtracheal jet ventilation
Although risk for injury cannot be determined from closed
before surgical airway need to be weighed against the pos-
claims analysis, it identifies patient safety hazards and stim-
sibility of making subsequent surgical airway more difficult.
ulates research.
Recommendations to Improve Management of Difficult
Conclusions
Tracheal Intubation
In summary, recent difficult intubation claims showed poor
Based on our findings and the literature, we offer some com-
outcomes and failures in judgment. Our results emphasize
mon sense recommendations related to training and edu-
the need to improve both practitioner skills and systems
cation. Human factors and nontechnical skills (situational
response when difficult or failed tracheal intubation is
awareness, communication, teamwork), or lack thereof, are
encountered.
important drivers of adverse difficult airway management
outcomes.21–25 Didactics may be useful to impart knowl-
edge and familiarize practitioners with current guide- Acknowledgments
lines but are not adequate by themselves. Practitioners The authors acknowledge the closed claims reviewers from
must familiarize themselves with locally available airway the American Society of Anesthesiologists (Schaumburg,
equipment, which should be placed appropriately within Illinois) and participation of the following liability insur-
the construct of published difficult airway guidelines.8,16,17 ance companies who have given permission to be acknowl-
Simple task trainers and/or dedicated manikins should edged: Anesthesia Service Medical Group, Inc. (San
be used to train appropriate handling of this equipment. Diego, California); COPIC Insurance Company (Denver,
Correct application of equipment, according to recent Colorado); ISMIE Mutual Insurance Company (Chicago,
guidelines, when faced with complex and unanticipated Illinois); MAGMutual Insurance Company (Atlanta,

Anesthesiology
Joffe et al. 2019; 131:818–29 825
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 Perioperative Medicine

Georgia); MLMIC Insurance Company (New York, New 4. Fornebo I, Simonsen KA, Bukholm IRK, Kongsgaard
York); Midwest Medical Insurance Company (Minneapolis, UE: Claims for compensation after injuries related to
Minneapolis); NORCAL Mutual Insurance Company airway management: A nationwide study covering 15
(San Francisco, California); Physicians Insurance A Mutual years. Acta Anaesthesiol Scand 2017; 61:781–9
Company (Seattle, Washington); Preferred Physicians 5. Cook TM, Woodall N, Frerk C; Fourth National Audit
Medical Risk Retention Group (Overland Park, Kansas); Project: Major complications of airway management in
Risk Management Foundation (Cambridge, Massachusetts); the UK: Results of the Fourth National Audit Project
State Volunteer Mutual Insurance Company (Brentwood, of the Royal College of Anaesthetists and the Difficult
Tennessee); The Doctors’ Company (Napa, California); and Airway Society. Part 1: anaesthesia. Br J Anaesth 2011;
The University of Texas System (Austin, Texas). 106:617–31
6. Caplan RA, Benumof JI, Berry FA, Blitt CD, Bode
Research Support RH, Cheney FW, Connis RT, Guidry OF: Ovassapian:
Supported in part by the American Society of guidelines for management of the difficult airway. A
Anesthesiologists (Schaumburg, Illinois) and the Anesthesia report by the American Society of Anesthesiologists
Quality Institute (Schaumburg, Illinois). All opinions Task Force on Management of the Difficult Airway.
expressed are those of the authors and do not reflect the policy Anesthesiology 1993; 78:597–602
of the American Society of Anesthesiologists or Anesthesia 7. Caplan RA, Benumof JI, Berry FA, Blitt CD, Cheney
Quality Institute. REDCap (Research Electronic Data FW, Connis RT, Guidry OF, NIckinovich DG:
Capture) electronic data capture tools hosted at University Practice guidelines for management of the difficult
of Washington (Seattle, Washington) was provided by the airway: An updated report by the American Society
Institute of Translational Health Science through grant No. of Anesthesiologists Task Force on Management
UL1 TR002319 from the National Center for Advancing of the Difficult Airway. Anesthesiology 2003;
Translational Sciences of the National Institutes of Health 98:1269–77
(Bethesda, Maryland). Additional support was provided by 8. Apfelbaum JL, Hagberg CA, Caplan RA, Blitt CD,
institutional funding. Connis RT, Nickinovich DG, Hagberg CA, Caplan
RA, Benumof JL, Berry FA, Blitt CD, Bode RH,
Competing Interests Cheney FW, Connis RT, Guidry OF, Nickinovich DG,
Ovassapian A; American Society of Anesthesiologists
The authors declare no competing interests. Task Force on Management of the Difficult Airway:
Practice guidelines for management of the difficult air-
Correspondence way: An updated report by the American Society of
Address correspondence to Dr. Domino: Department of Anesthesiologists Task Force on Management of the
Anesthesiology and Pain Medicine, Box 356540, University Difficult Airway. Anesthesiology 2013; 118:251–70
of Washington, Seattle,Washington 98195-6540. kdomino@ 9. Schroeder RA, Pollard R, Dhakal I, Cooter M,Aronson
uw.edu. Information on purchasing reprints may be found at S, Grichnik K, Buhrman W, Kertai MD, Mathew JP,
www.anesthesiology.org or on the masthead page at the Stafford-Smith M: Temporal trends in difficult and
beginning of this issue. Anesthesiology’s articles are made failed tracheal intubation in a regional community
freely accessible to all readers, for personal use only, 6 anesthetic practice. Anesthesiology 2018; 128:502–10
months from the cover date of the issue. 10. Cheney FW, Posner K, Caplan RA, Ward RJ:

Standard of care and anesthesia liability. JAMA 1989;
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Appendix: Examples of Inappropriate Difficult unsuccessful. A difficult airway cart was called, but it was a
Airway Management floor away. Eventually a surgical airway was performed after
the patient arrested. The patient sustained brain death.
Inadequate Preoperative or Airway Evaluation (Failure to
Recognize a Potentially Difficult Airway) Case 2
Case 1 A 55- to 65-yr-old American Society of Anesthesiologists
A morbidly obese 30- to 40-yr-old woman with severe pre- (ASA) Physical Status III man with metastatic laryngeal
eclampsia was scheduled for elective cesarean section. The cancer treated with neck radiation was scheduled for a gas-
preoperative assessment was cursory and did not describe trostomy tube placement due to dysphagia. While a com-
preeclampsia, an airway exam, other pertinent physical and plete preoperative evaluation had been performed earlier, it
laboratory findings, or the patient’s past history of a difficult was not available at the time of surgery.The anesthesiologist
endotracheal intubation.After multiple unsuccessful attempts performed a hasty assessment with limited airway evalu-
at a subarachnoid block, general anesthesia was induced via ation. General anesthesia was induced with propofol and
rapid sequence induction using propofol and succinylcho- succinylcholine. The patient’s trachea could not be intu-
line.The patient’s mouth was difficult to open and bag-mask bated and the patient could not be ventilated with mask or
ventilation difficult. Additional succinylcholine was admin- supraglottic airway. Transtracheal jet ventilation was unsuc-
istered, a laryngoscope inserted, and the larynx was not cessful and caused a pneumothorax. A surgical airway was
visualized. A supraglottic airway was placed, but ventilation performed after the patient arrested. The patient was resus-
was unsuccessful.Two-handed bag-mask ventilation was also citated but died the next day.

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 Perioperative Medicine

Failure to Plan for a Difficult Tracheal Intubation Anesthesia was induced with a rapid sequence induction
(Induction) with propofol and succinylcholine. Upon laryngoscopy,
considerable tongue and paraglottic swelling was noted.
Case 3
The cords could not be visualized; however, the anesthesi-
A 55- to 65-yr-old ASA IIIE man with a neck abscess was
ologist successfully intubated the patient’s trachea using a
scheduled for incision and drainage by an ear-nose-throat
bougie passed under the epiglottis. At the end of the pro-
surgeon.The anesthesiologist decided to do a rapid sequence
induction after noting blood and pus in the posterior phar- cedure, an anesthesia team member decided to extubate
ynx. The cords were not visualized on direct laryngoscopy. the patient because the patient was fighting the tube and
Bag-mask ventilation was attempted but was unsuccessful. appeared strong. The oxygen saturation measured by pulse
Ventilation was also not successful after a supraglottic air- oximetry (Spo2) fell after extubation and an anesthesia team
way was placed. The surgeon was called to the room to member attempted to open the airway with placement of
perform an emergency surgical airway, but there were not a nasal and oral airway. Mask ventilation was very difficult.
any instruments available in the room.The patient sustained Many intubation attempts were made using a variety of
anoxic brain injury and later died. blades and devices. An ear-nose-throat surgeon was called
to perform a surgical airway, who suggested a supraglot-
Case 4 tic airway be inserted instead. After the supraglottic airway
A 55- to 65-yr-old ASA IIIE woman with neck swell- was placed, the patient became impossible to ventilate and
ing, hoarseness, and shortness of breath was brought to went into cardiac arrest. The surgical airway was placed
the operating room for drainage of a neck hematoma with some difficulty. The patient sustained severe hypoxic
post–cervical spine fusion. The anesthesiologist per- brain and died.
formed a rapid sequence induction before the surgeon
was present. Multiple attempts at intubation were made Case 7 (Intensive Care Unit)
using direct laryngoscopy, all without success. Ventilation A 60- to 70-yr-old ASA III man with an odontoid fracture/
was difficult and the patient arrested. The surgeon arrived C2 dislocation after an accident in a halo collar was extu-
and attempted to perform an emergency surgical airway, bated by the intensive care unit team after he met mechan-
at which time the anesthesiologist successfully intubated ical extubation criteria. The patient’s trachea had been
the patient’s trachea as the hematoma was drained. The initially intubated at the accident scene. Immediately after
patient was resuscitated but later died of anoxic brain extubation, the patient developed upper airway obstruc-
damage. tion, bag-mask ventilation was unsuccessful, and the patient
arrested. An anesthesiologist was called but could not intu-
Case 5 bate. A difficult airway cart had to be retrieved from storage.
A 20- to 30-yr-old ASA IIIE woman was scheduled for The breast plate was removed and a surgical airway inserted;
incision and drainage of a submental salivary gland abscess. however, the patient had little neurologic activity and sup-
The anesthesiologist suggested monitored anesthesia care port was withdrawn.
due to airway concerns, but the surgeon desired general
anesthesia. Anesthesia was induced with propofol, fentanyl, Failure to Use a Supraglottic Airway as a Bridge to
and succinylcholine, and the cords were not visualized with Oxygenation
direct laryngoscopy. The anesthesiologist called for a video Case 8
laryngoscope, but the nurses were not able to find it. The A 50- to 55-yr-old ASA I woman underwent bilateral
patient could not be ventilated and went into cardiac arrest. breast augmentation under monitored anesthesia care
The anesthesiologist asked the nurses to bring the difficult using propofol, ketamine, and fentanyl in a plastic sur-
airway cart, which they also couldn’t find. The anesthesi- geon’s office. Due to airway obstruction, general anes-
ologist had to leave the room to search for the cart. The thesia was induced, succinylcholine was administered,
anesthesiologist asked the surgeon to perform an emer- and the anesthesiologist attempted (unsuccessfully)
gency cricothyrotomy. However, the surgeon insisted that to intubate. Spo2 decreased to 70% for 40 min during
an electrocautery to be set up first. Nine minutes after car- the many attempts to mask ventilate and intubate the
diac arrest, a surgical airway was secured by the surgeon. patient’s trachea. The surgeon performed a cricothy-
The patient was resuscitated but remained in a persistent rotomy after the patient had marked bradycardia and
vegetative state. hypotension. The patient was quickly resuscitated after
the cricothyrotomy and required treatment for bilateral
No Backup Plan for Difficult Reintubation (Extubation) pneumothoraces. The patient recovered without neuro-
Case 6 (Operating Room) logic injury, but she complained of difficulty swallow-
A 40- to 50-yr-old ASA IIE man was scheduled for inci- ing, a visible scar, an altered voice, and posttraumatic
sion and drainage of a submandibular/submental abscess. stress disorder.

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 Management of Difficult Tracheal Intubation

Perseveration Delay in Surgical Airway during “Can’t Intubate, Can’t

Case 9 Oxygenate”
A 60- to 70-yr-old ASA III obese man underwent gen- Case 11
eral anesthesia using a supraglottic airway for a urologic A 1- to 3-yr-old child underwent a cleft palate repair under
procedure in the lithotomy position. Due to inadequate general anesthesia and was extubated at the end of the case.
ventilation, the anesthesiologist tried to intubate with In the recovery room, the patient had substernal retractions
direct laryngoscopy, but was unable to visualize the vocal with Spo2 of 85 to 89%. An hour later, the patient required
cords. Mask ventilation was difficult and the anesthesiolo- cardiac resuscitation due to heart rate of 30 per min and
gist called for help. Three additional anesthesiologists also cyanosis. Multiple intubation attempts and supraglottic air-
attempted direct laryngoscopy multiple times and all failed. way insertion were made for more than an hour before a
An intubating supraglottic airway was attempted without surgical airway was performed. At that time, the patient was
success. The patient arrested. Finally, the patient’s trachea asystolic and had a tension pneumothorax.The patient died.
was successfully intubated and he was resuscitated. He sus-
tained severe anoxic brain damage and later died in a long- Case 12
term care facility. A 50- to 60-yr-old ASA III morbidly obese woman with
obstructive sleep apnea presented for elective laparoscopic
Case 10 gastric bypass. The patient’s preoperative airway evaluation
The anesthesiologist was called urgently to the cardiac did not predict a difficult intubation. After induction with
catheterization laboratory to intubate a 60- to 70-yr-old propofol and rocuronium, ventilation was easy. The larynx
morbidly obese ASA IVE man undergoing coronary revas- was not visualized on direct laryngoscopy on two attempts.
cularization after a myocardial infarction. The anesthesiol- After the second attempt, bag-mask ventilation became more
ogist gave the patient midazolam before performing direct difficult, Spo2 was in the 80s, and the anesthesiologist called
laryngoscopy but was not able to visualize the vocal cords for help. A supraglottic airway was inserted without adequate
upon multiple attempts. Bag-mask ventilation became dif- ventilation and a difficult airway cart brought to the operat-
ficult. A second anesthesiologist was called and was also ing room.The surgeon was called multiple times but without
unable to intubate with multiple direct laryngoscopies and response as ventilation became impossible. The patient had
a fiberoptic intubation. Spo2 decreased to 25 to 30% and the a hypoxic cardiac arrest. The surgeon arrived 22 min after
patient arrested. A surgeon was called to place a cricothy- induction and secured an emergency surgical airway. The
rotomy. The patient was resuscitated but had severe anoxic patient was resuscitated but sustained hypoxic brain damage
brain damage and died. requiring assistance with activities of daily living.

Anesthesiology
Joffe et al. 2019; 131:818–29 829
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