Journal of Intensive Care Medicine
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Complications of Emergency Tracheal Intubation: Immediate Airway-related Consequences: Part II
Thomas C. Mort
J Intensive Care Med 2007; 22; 208
DOI: 10.1177/0885066607301359
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Complications of Emergency Tracheal
Intubation: Immediate Airway-related
Consequences: Part II
Thomas C. Mort, MD
Airway management in the stable, elective operating room
patient is typically exceptionally safe. Conversely, the
acute deterioration of an intensive care unit or floor
patient being rescued by a clinician unfamiliar with the
patient’s past and current history combined with an
incomplete physical examination places the critically ill
patient in a precarious, potentially life-threatening position. Emergency airway management in remote locations
outside the confines of the operating room is complex and
stressful due to immense airway challenges coupled with
the high risk of hemodynamic and airway complications.
Despite the commonality of difficulties with mask ventilation, laryngoscopy, and tracheal intubation in this population, relatively sparse literature deals with these subjects.
Consequences of airway management should be openly
discussed as a first step toward improving airway safety.
This is the second of 2 reviews, “Complications of
Emergency Tracheal Intubation,” and focuses on the
immediate airway-related consequences during emergency tracheal intubation in the remote location.
Key words:
airway management; intubation; complication
Of note to the reader: This review has made every
effort to evaluate available literature regarding the
topics at hand; however, emergency airway management is relatively still in its infancy regarding
studies defining consistent complications parameters
and reporting mechanisms. Therefore, the Hartford
Hospital database (3 700+ patients) was used, in
part, to convey and provide a basis for a discussion
on particular facets of emergency airway care that
are currently underappreciated or underreported.
Although several peer-reviewed publications have
resulted from this database, it continues to grow and
From Department of Anesthesiology, Hartford Hospital, Hartford,
CT.
Received Nov 6, 2005, and in revised form Oct 12, 2006. Accepted
for publication Oct 19, 2006.
Address correspondence to Thomas C. Mort, MD, Department of
Anesthesiology, 80 Seymour Street, Hartford Hospital, Hartford,
CT 06015, or e-mail [email protected].
Mort TC. Complications of emergency tracheal intubation: immediate airway-related consequences: part II. J Intensive Care Med.
2007;22:208-215.
DOI: 10.1177/0885066607301359
208
provide currently unpublished trends, incidences,
and risks of emergency intubation that are provided
to the reader for edification purposes only. This is the
second of 2 articles reviewing the major complications of emergency airway management.
The sharp contrast between the elective patient in
the operating room (OR) and the critically ill patient
requiring tracheal intubation in the remote location
is vast and certainly problematic. The elective patient
is typically ambulatory, has received nothing by
mouth (NPO) for more than 6 to 8 hours, and has
undergone a history and physical examination with
appropriate preoperative screening tests. In contrast,
a “stat” call to intubate a vomiting intensive care unit
(ICU) patient with hyperglycemia, febrility, tachycardia, tachypnea, hypotension, a metabolic acidosis,
mental status changes, and marginal oxygenation
may be challenging to the clinician. A hurried,
abridged history and physical examination contributes further to compromised patient safety.
This review focuses on the immediate airwayrelated consequences that could be considered significant and potentially life-threatening. Although
important, dental damage, awareness, lip and oral
cavity lacerations, and the like will not be discussed
in this review.
The consequence of most airway-related complications involves hypoxemia. Complications such as
esophageal intubation (EI), regurgitation, aspiration,
multiple intubation attempts, and main stem bronchus
intubation (MSBI) may each, singly or in combination, lead to oxygen desaturation. In an attempt to
thwart or limit desaturation during the intubation
process and provide a margin of safety in the event
of airway difficulties, efforts to provide adequate oxygen reserve should be aggressively pursued.
Elective preoxygenation incorporating either 4 to
8 maximal forced vital capacity breaths of 100% oxygen or 4 minutes of 100% oxygen by using a tightfitting face mask effectively elevates the PaO2 to
more than 400 mm reliably in the otherwise stable
patient [1-9]. The critically ill patient may be recalcitrant to standard noninvasive oxygen therapy.
Despite optimal preoxygenation, the pulse oximetry
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Emergency Intubation Complications
oxygen saturation (SpO2) may barely clear the 90%
saturation range commensurate to arterial oxygen
tensions in the 55 to 100 mm Hg range, thus rendering the patient at risk for potentially rapid desaturation [10]. Hypoxemia may be exaggerated if multiple
intubation attempts, EI, aspiration, uncorrected
MSBI, or loss of the airway complicates the intervention [10,11].
Preoxygenation
The objective of emergency airway management is
to primarily support oxygenation and ventilation
and provide airway protection, not simply to perform endotracheal intubation. Mask ventilation and
preoxygenation efforts have received tremendous
emphasis in the elective OR setting, but this cannot
be said for the higher risk ICU patient. The crucial
need for maximizing the patient’s oxygen stores in
the arterial, venous, and tissue beds⎯and not just
the lungs (functional residual capacity)⎯may be difficult to achieve, but effort should be expended,
nonetheless [10].
Mask ventilation may be extremely difficult in the
setting of obesity, limited jaw and cervical spine
mobility, a lack of dentition, a bearded face,
cachexia, facial bone overgrowth, facial trauma,
edema (external and internal), and age older than 60
years [11]. The effectiveness of preoxygenation has
been found to be limited in those with significant
cardiopulmonary pathology such as congestive heart
failure, pneumonitis, and respiratory failure complicated by excessive secretions, in contrast to patients
having their airway secured solely for the purpose of
“airway protection” [10]. Further investigation toward
identifying improved preintubation oxygen-delivery
methods for the critically ill population on the verge
of tracheal intubation is warranted.
Hypoxemia
What level of oxygen saturation (based on pulse
oximetry) represents a reasonable cutoff for clinical
reference? A SpO2 of less than 90% equates to a PaO2
of 58 to 61 mm Hg and appears to have some support in the literature [6,8]. This level of arterial oxygen is situated on the downward slope of the
oxyhemoglobin saturation curve, and further desaturation beyond this point may be rapid. Table 1 summarizes the SpO2, the estimated PaO2, and the
expected systemic hemodynamic response. The literature is replete with studies reporting an extremely
Table 1.
SpO2
Physiologic Changes With Hypoxemia
PaO2
Systemic Response
90
80
70
58-61/mm
50-53
36-39
60
28-32
<60
<30
None to mild ↑ HR, BP
None to moderate ↑ HR, BP
Moderate to significant ↑ HR,
BP, occasional ↓ HR < 40
Significant ↑ HR, BP, common
HR slowing
HR slowing in many, brady
cardiac-hypoxia arrest
SpO2 = pulse oximetry oxygen saturation; PaO2 = partial pressure
of arterial oxygen; BP = blood pressure; HR = heart rate; brady =
bradycardia.
low rate of hypoxemia during emergency intubation
of less than 2% to 10% [6-10,12-15], yet studies
specifically designed to determine the incidence of
hypoxemia, based on well-defined parameters, suggest a significantly higher incidence of 21% to 28%
[10,16-18].
The Influence of Age, Comorbid, and
Pathologic Conditions on Hypoxemia
Currently, there is little specific literature reporting
the influence of age, comorbid conditions, and particular pathologic states on the incidence of hypoxemia during emergency airway management [11].
Reviewing the Hartford Hospital database, age,
independent of all other factors, appeared to
increase the incidence of hypoxemia in the young
(<30 years, 14%) to the octogenarians and beyond
(≥80 years, 22%), representing a 50% rise. Moreover,
preexisting comorbidities such as hypertension, coronary artery disease, congestive heart failure, chronic
obstructive pulmonary disease (COPD), diabetes mellitus, and renal dysfunction appeared to influence
the incidence of hypoxemia by increasing the risk
of hypoxemia in a step-wise fashion of approximately 7% per comorbidity.
Overall, up to one third may suffer hypoxemia to
differing degrees, yet several pathologic conditions
may have influenced this rate. On one extreme, a
patient with a grand mal seizure had the lowest rate
of hypoxemia during intubation (6%) compared
with patients with primary pulmonary pathology
complicated by copious secretions (65%). Conversely,
pulmonary pathology with fewer secretions had a
much lower incidence of desaturation to less than
90% (COPD, 21%; aspiration pneumonitis, 25%;
bacterial/viral pneumonitis, 23%; and pulmonary
sepsis, 17%). Depending on the site of injury, 27%
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209
Mort
to 30% of trauma patients experienced hypoxemia.
Other specific groups included stroke/intracerebral
hemorrhage (often intubated for mental deterioration and airway protection), 15%; acute myocardial
infarction, 13%; congestive heart failure, 16%; cardiogenic shock, 15%; and upper gastrointestinal
bleeding, 28% (Hartford Hospital database).
The body mass index (BMI, body weight in
kg/height in m2) had a significant effect on the rate
of desaturation. A normal BMI (<25) had an incidence of 17%, as did the overweight category (BMI,
25-30). However, as the BMI increased into the
obese categories, there was a clear linear relationship: obese, 23% (BMI, 30-35); morbidly obese, 31%
(BMI, 35-50); and super morbidly obese, 34% (BMI
>50). The patient’s oxygenation reserves, obesityrelated pulmonary limitations, and difficulty encountered when handling the obese patient’s airway may
influence the incidence of hypoxemia [1,19].
Specific concerns for emergency airway management that the airway clinician should appreciate
include (1) the limits of denitrogenation and adequate preoxygenation [10], (2) the rapid desaturation that may occur between face mask removal
and tracheal intubation, (3) the increased incidence
of multiple intubation attempts and desaturation,
and (4) the increased incidence of encountering a
“difficult airway” in the emergency setting [20].
An emergency department airway textbook suggests that if time is limited, one can forego the standard 3 to 5 minutes of 100% oxygen administration
and simply accomplish preoxygenation with 4 to 8
vital capacity breaths of 100% oxygen [21]. A critically ill patient would likely be incapable or uncooperative enough to perform such a request in the
face of tachypnea, agitation, altered mental status,
intoxication, and concurrent hypoxemia.
Airway-related Complications
Airway-related complications in the emergency setting are similar in variety but easily outflank their
elective counterparts in magnitude, occurrence, and
consequence. Excessive secretions, edematous airway tissues, and an increased tendency for airway
bleeding and swelling from instrumentation may
plague these interventions. Despite numerous studies of intraoperative anesthesia care and emergency
department airway management, the true incidence
of complications such as laryngospasm, bronchospasm, bleeding, tissue trauma, aspiration, inadequate ventilation, difficult intubation, difficulties
with extubation, and MSBI remain relatively poorly
documented in the literature.
210
Esophageal Intubation
Tachycardia
Regurgitation
Hypertension
Hypoxemia
Aspiration
Mainstem intubation
Hypotension
Bradycardia
Multiple Intubation attempts
Cardiac Arrest
Fig 1. This schematic depicts the central role that
hypoxemia plays in emergency airway management.
Complications and difficulties in airway management
contribute to hypoxemia, which may, in turn, lead to
additional patient morbidity and potentially mortality.
The efforts of the American Society of Anesthesiologist’s closed claim analysis have brought many
of these adverse respiratory events into the spotlight [22-25], but their incidences or risk factors
have been addressed in only a few instances [15-18,
20]. The relative lack of reporting may be related to
1. the inability to establish a consistent definition
or parameter of a complication,
2. little emphasis on airway management safety in
the emergency setting for the critically ill,
3. the minimization of concern for mishaps and critical events if they do not lead to life-threatening
consequences, and
4. the fear of medicolegal repercussions, embarrassment, and scrutiny by peers or the hospital
administration [20, 26-30].
Hypoxemia, often the consequence of an airwayrelated event, is the common link to altering the
patient’s already fragile physiologic state [16-18]
(Figure 1).
EI
Esophageal intubation and more specifically, the lack
of its recognition, has been identified as a leading
adverse respiratory event and is an important contributing factor in the occurrence of hypoxemia, regurgitation and aspiration, severe central neurologic damage,
and death. Its incidence varies by the series but is commonly 2% to 9% in the emergency setting [12-14,16,18,
20,31]. Morbidity and mortality related to EI have been
recently reviewed, and action to reduce its ill effects by
vigilant monitoring and rapid detection is warranted
[17,18]. Failure to recognize EI is not limited to inexperienced trainees, and despite the use of verification
devices, EI-related catastrophes persist.
Unrecognized EI is often preventable with better
monitoring because indirect clinical signs of detecting
tracheal tube location are imprecise and should be
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Emergency Intubation Complications
Table 2.
Methods of Endotracheal Tube Verification
Non-Fail-safe Methods
Less Than Fail-safe Methods
Fail-safe Methods
Checking breath sounds
Chest radiography
Epigastric auscultation
Reservoir bag movement
Reservoir bag compliance
Cuff maneuvers and cuff palpation
Condensation of vapor in ETT
Expelled gas with sternal compression
Transtracheal illumination
Pulse oximetry
CO2 detection
Esophageal detector device
Direct view of ETT through glottis
Fiberoptic view of glottis/trachea
Adapted from references 31 and 34. ETT = endotracheal tube.
augmented by capnography or other similar technology [22-25]. Auscultation of breath sounds, tube
condensation, chest wall excursions, reservoir bag
compliance and refilling, as well as many other
methods of detecting tracheal tube placement are
not infallible; each has shortcomings and difficulty
with interpretation under normal circumstances.
Their usefulness is reduced further under emergent
or urgent circumstances [31-34].
The fail-safe detection method of directly viewing the endotracheal tube (ETT) between the vocal
cords is impractical in 10% to 20% of emergency
patients due to anatomic limitations [16]. Fiberoptic
verification, ideally, is fail-safe yet is limited by the
presence of blood and secretions in the airway and
ETT, the need for qualified personnel to perform
the bronchoscopy, and rapid access to such
advanced equipment (Table 2) [31,34].
Intuitively, the use of monitors and the performance of verification maneuvers do not reduce the
incidence of EI, but they may foreshorten the time
from ETT placement (misplacement) and its detection. Gastroesophageal insufflation from the misplaced ETT increases the risk of regurgitation and
aspiration [16-18]. The risk of aspiration, bradycardia, hypoxemia, and cardiac arrest is considerable
in those who experience EI in the emergency situation (Figure 2), especially when the ETT position
is confirmed without the benefit of nearly fail-safe
devices (capnography) [16-18]. Therefore, confirming ETT placement with a rapid, reliable, and
portable technique should be practiced in the delivery of emergency airway management services.
Regurgitation and Aspiration
The aspiration of gastric contents into the tracheobronchial tree is, fortunately, a rare occurrence in
30%
20%
10%
0%
Regurgitation
Aspiration
Bradycardia
Non-EI
Dysrhythmia
Cardiac Arrest
EI
Fig 2. Incidence of complications associated with (EI)
and without (Non-EI) esophageal intubation [17, 18]. All
EI-related complications were clinically significant when
compared with the non-EI group (P < .001).
the elective anesthesia setting. “Silent” regurgitation
and aspiration may occur frequently in the sleeping
adult as well as during anesthetic induction, maintenance, emergence, and postoperatively, with or
without the benefit of airway protection (intubation). The frequency of perioperative pulmonary
aspiration in adults and pediatric patients is approximately 1:2 600 [31,35]. The emergency setting itself,
and patients with a higher anesthesia risk classification, have a higher risk of aspiration [35,36]. The
incidence of regurgitation under emergency circumstances varies between 1.6% and 8.5% [12,16,18,37],
whereas the aspiration risk is 0.4% to 5% [13-16,
20,37,38].
The increased risk in the emergency situation is
because the airway manager has little control over
NPO status, a full stomach, intestinal ileus, gastrointestinal pathology (ie, bleeding, disease-induced
gastroparesis), or alteration of the airway protective
reflexes (Table 3). Statistics presented by Warner
[35] and Olsson et al [31] suggest the perioperative
aspiration risk is nearly 50 times less than in the
emergency setting (1:2 600 cases versus 1:50).
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211
Mort
Table 3.
Risk Factors for Regurgitation and Aspiration
Recent oral intake, enteral feeding
GI pathology
Bleeding, nausea, vomiting, obstruction
Ileus, incompetent sphincter, instrumentation
of GI tract (ie, NGT)
Opioids, CNS depressants, other medications
Neurologic neuromuscular disease
Extremes of age, debility
Air swallowing
Cardiovascular instability
Airway management difficulties
Esophageal intubation
Anesthetic induction agents
Neuromuscular blocking agents?
Difficult mask ventilation with aerodigestive
tract insufflation
Multiple laryngoscopic attempts
Chest compressions/CPR
Coma/unconsciousness of any etiology
GI = gastrointestinal; CNS = central nervous system; NGT = nasogastric tube; CPR = cardiopulmonary resuscitation.
Commensurate hypoxemia during regurgitation
is the rule: Less than 10% of those who regurgitated
or aspirated gastric contents maintained their SpO2
at more than 90%, respectively [16-18]. The risk of
bradycardia and cardiac arrest due to profound
hypoxemia was also exaggerated in the presence of
regurgitation and aspiration [16-18,31,35,36]. A riskreduction strategy that included the immediate
availability of accessory airway devices for emergency intubation coupled with equipment verifying
ETT placement led to a reduction of regurgitation
and aspiration by 43% and 75%, respectively [17,
39,40]. Upper gastrointestinal bleeding is particularly
risky (regurgitation, 4 times; aspiration, 7 times) in
undergoing emergency tracheal intubation compared
with nonbleeding patients [41,42].
Although it has been taught that a rapid-sequence
intubation is specifically indicated to reduce the risk
of aspiration, recent data suggest that an awake or
light sedation approach to emergency intubation
may be nearly equally protective, with less overall
risk to the patient, when the patient displays factors
associated with a difficult airway [43].
Airway Injury
Defining the airway as the area from the nose to the
tracheobronchial tree, represents the anatomical
sites within the “airway” and may sustain minor,
212
major, and even catastrophic degrees of trauma
during routine and emergency tracheal intubation.
Many injuries are short-lived or nondisabling, but
some may lead to life-threatening consequences.
Major airway injury may occur during routine or
emergency intubation unbeknownst to the practitioner and patient. Closed-claim analysis found that
difficult intubation was judged to be a factor in 39%
of laryngeal, pharyngeal, esophageal, and tracheal
injuries, and some led to death from mediastinal
soilage through perforation [44]. Severe esophageal
injuries often involve a difficult intubation; yet, in
one half of the esophageal perforation cases, intubation was believed to have been without consequence and atraumatic [22-25,44].
Pharyngolaryngeal mucosal injury may only present with nonspecific symptoms but more often
resolves without sequelae. Major airway injury is
often shrouded by generalized signs and symptoms,
and this contributes to the difficulties with diagnosis.
Furthermore, patients who remain intubated, heavily
sedated, and unable to communicate may limit the
practitioner’s consideration of the existence of an
injury [44]. Any occurrence of a pneumothorax, subcutaneous emphysema, pneumomediastinum, dysphasia, chest pain, coughing, and deep cervical pain
advancing to a febrile state should be investigated in
light of difficulty encountered during airway management. Early signs of a perforation are not the rule,
hence, a delay in diagnosis is common. It would
be prudent to communicate to the primary care
providers any difficulties that arise during the intubation process so that symptomatology may be
promptly investigated [44].
Bronchial Intubation
Main stem bronchus intubation (MSBI) occurs relatively frequently under elective anesthetic conditions but is quickly detected in most cases by initial
chest auscultation and determination of the appropriate depth of the ETT. If it remains undetected
and uncorrected, it may lead to hypoxemia, atelectasis, bronchospasm, lobar collapse, coughing, and
the potential for barotrauma. Palpation of the
inflated cuff above the sternal notch is a useful test
in elective patients to verify the location of the ETT
and may decrease the risk of MSBI or impingement
of the ETT on the carina [45]. Fiberoptic evaluation
is definitive and any of the above clinical signs
should prompt its use. Major morbidity may occur
quickly or be delayed [46,47]. Any unexplained
oxygen desaturation, coughing, bronchospasm, or
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Emergency Intubation Complications
changes in peak inspiratory pressures (volume controlled ventilation), or an abrupt or gradual reduction in tidal volume (pressure control ventilation),
should prompt evaluation [45-47].
Undetected MSBI discovered by a postintubation
chest radiograph in the emergency intubation scenario is relatively common (3.5%). The incidence
nearly triples after difficult intubation (EI, regurgitation, and ≥3 intubation attempts) [16]. Schwartz
et al [47] noted 15.5% of ETT placed in an emergency were inappropriately positioned (within 2
cm of the carina on chest radiograph), especially in
women. The fiberoptic bronchoscope is one of the
most underutilized yet clinically applicable diagnostic tools to investigate a suspected MSBI and
potentially reverse its consequences.
Simplifying the approach to emergency airway
management has been stressed in the emergency
department literature to recommend that a rapidsequence intubation technique is the preferred
approach compared with sedation alone [12-14,21,
51]. Unfortunately, airways are as individual as their
owners, and the skill level amongst practitioners is
extremely variable. Thus, each patient may benefit
from an individualized approach rather than a standard regimen or protocol. Incorporating an airway
management strategy that provides practitioners
with suggested management maneuvers that
depend on their own personal skill and experience,
the airway itself, and any previously failed technique, has recently gained momentum and may
lead to a lower incidence of complications and loss
of the airway [39,40,43,52-55].
Multiple Intubation Attempts
What is the threshold number of intubation
attempts that should prompt the practitioner to categorize the number of attempts as an “airway complication”? National guidelines define difficult
intubation as the inability to intubate within 3
attempts [48,49]. These guidelines have further suggested, on the basis of expert opinion, that the
practitioner should limit the number of laryngoscopic attempts to 3, at which point alternative airway techniques should be used to secure the
airway.
Limiting laryngoscopy attempts is suggested
because of concern that repeated interventions may
potentiate tissue trauma, bleeding, and mucosal
edema and may transform a ventilatable airway to
one that is not (cannot ventilate, cannot intubate)
[48,49]. This opinion has recently been substantiated by a study that demonstrated that the rate of
complications was directly related to the number of
laryngoscopic attempts during emergency airway
management. The risk of airway and hemodynamic
complications increased with the second laryngoscopic attempt and accelerated rapidly with 3 or
more attempts [16,43].
A high level of suspicion should be placed on all
critically ill patients who require emergency airway
management, and each should be regarded as
potentially difficult (“unanticipated difficult airway”). A limit of 1 or 2 attempts under optimal conditions before rapidly moving to a secondary plan
or an alternative strategy seems prudent in light of
the complications associated with repetitive laryngoscopy [16,17,39,40,50].
Current Literature
Although a large number of emergency intubation
studies are available, relatively few report a wide
breadth of complications. The rate of complications, adverse events, and serious consequences
are categorized differently by the various authors,
with no clear defining parameters to assist the
reader in comparing the studies. Many of these
studies have not focused on 2 important questions:
What was the specific immediate airway-related
complications of the emergency intubation? And
what may be done to limit patient morbidity?
(Table 4).
Conclusion
Airway-related complications appear to be relatively
common in the emergency management of the airway outside the OR. These critically ill patients
appear to be at higher risk for numerous critical incidents and adverse events than their elective counterparts. Although there is no panacea to halt these
mishaps from taking place, improving the delivery of
emergency airway service by optimizing medical
staff preparation and education; assuring equipment
availability in a variety of patient locations; and formulating an “airway management game plan” to
handle the potential failure of an airway securing
technique should provide an improved level of
patient care and reduce the risk of airway-related
complications in this population.
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213
Mort
Table 4.
Airway-Related Events
First Author
Hypox
(%)
Mateer [9]
30
Sakles [12]
3.3
EI
(%)
5.4
Regurg
(%)
1.6
Tayal [13]
18
Dufour [14]
Schwartz [15]
Walls [18]
Aspir
(%)
?
Gnauck [37]
MSBI
(%)
3.0
5.3
14
28
0.5
1.4
8
4
4
8
?
?
?
?
?
2.3
8.5
3.3
8.5
22
Norwood [38]
0.4
1
1.5
2
0
?
0.3
3
0.2
Rotondo [59]
Vijayakumar [60]
Mort [16, 20]
1.1
6
Levitan [57]
Taryle [58]
“Cric”
(%)
2.6
Sagarin [51]
Sagarin [56]
M. Att
(%)
2.5
20
1.7
4.85?
1.5
3.5
6?
9
5.3
1.6
5.2
4
3
0.7
7
1
6?
9
3.1
0.4
Comment by Authors
We…monitor pulse oximetry
for intubations in ED
8% complication rate, “low
rate of serious complications”
Complication rate is high,
consider formal training
RSI is a safe and effective
approach to intubation
“Associated with a significant
frequency of complications”
Only 3% have serious
complications
Intubation protocols using
paralyzing agents are needed
Intubation is a safe method
of airway control
High success rate, ED
residents are successful
High success rate, low rate of
serious adverse events
High success rate, low rate
of complications
1.4% had major adverse events,
RSI…few major events
“Low morbidity, no mortality
and can be used safely”
15% had difficult intubations
Airway and hemodynamic
mishaps are very common
Hypox = hypoxemia; EI = esophageal intubation; Regurg = regurgitation; Aspir = aspiration; MSBI = mainstem bronchus intubation; M.
Att = multiple attempts (3+), Cric =cricothyrotomy; ED = emergency department; RSI = rapid-sequence intubation.
9.
References
1.
2.
3.
4.
5.
6.
7.
8.
214
Goldberg ME, Norris MC, Larijani GE, Marr AT, Seltzer JL.
Preoxygenation in the morbidly obese: a comparison of
two techniques. Anesth Analg. 1989;68:650-652.
Ggambee AM, Hertzka R, Fisher D. Preoxygenation techniques: comparison of three minute and 4 breaths. Anesth
Analg. 1987;66:468-470.
Valentine SJ, Marjot R, Monk CR. Preoxygenation in the
elderly: a comparison of the 4-maximal breath and 3-minute
techniques. Anesth Analg. 1990;71:516-519.
McCarthy G, Elliott P, Mirakhur K, McLoughlin C. A comparison of different pre-oxygenation techniques in the
elderly. Anaesthesia. 1991;46:824-827.
Benumof JL. Best method for both efficacy and efficiency?
Anesthesiology. 1999;91:603-605.
Benumof JL, Dagg R, Benumof R. Critical hemoglobin
desaturation will occur before return to an unparalyzed
state following 1 mg/kg intravenous succinylcholine.
Anesthesiology. 1997;87:979-982.
Baraka AS, Taha SK, Aouad MT, El-Khatib MF, Kawkabani NI.
Preoxygenation: comparison of maximal breathing and tidal
volume breathing techniques. Anesthesiology. 1999;91:612-616.
Farmery AD, Roe PG. A model to describe the rate of oxyhemoglobin desaturation during apnoea. Br J Anaesth.
1996;76:284-291.
10.
11.
12.
13.
14.
15.
16.
17.
Mateer JR, Olson DW, Stueven HA, Aufderheide TP.
Continuous pulse oximetry during emergency endotracheal
intubation. Ann Emerg Med. 1993;22:675-679.
Mort TC. The value of preoxygenation in the critically ill
patients requiring emergency intubation. Crit Care Med. 2005;
33:2672-2675.
Langeron O, Masso E, Huraux C, et al. Prediction of difficult mask ventilation. Anesthesiology. 2000;92:1229-1236.
Sakles JC, Laurin EG, Rantapaa AA, Panacek EA. Airway
management in the emergency department: a one year
study of 610 intubations. Ann Emerg Med. 1998;31:325-332.
Tayal VS, Riggs RW, Marx JA, Tomaszewski CA, Schneider
RE. Rapid-sequence intubation at an emergency medicine
residency: success rate and adverse events during a twoyear period. Acad Emerg Med. 1999;6:31-37.
Dufour DG, Larose DL, Clement SC. Rapid sequence intubation in the emergency department. J Emerg Med.
1995;13:705-710.
Schwartz DE, Matthay MA, Cohen NA. Death and other
complications of emergency airway management in critically ill adults. A prospective investigation of 297 tracheal
intubations. Anesthesiology. 1995;82:367-373.
Mort TC. Emergency tracheal intubation: complications
associated with repeated laryngoscopic attempts. Anesth
Analg. 2004;99:607-613.
Mort TC. The incidence and risk factors for cardiac arrest
during emergency tracheal intubation: a justification for
Journal of Intensive Care Medicine 22(4); 2007
Downloaded from http://jic.sagepub.com at UNIV OF PITTSBURGH on January 1, 2008
© 2007 SAGE Publications. All rights reserved. Not for commercial use or unauthorized distribution.
Emergency Intubation Complications
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
incorporating the ASA Guidelines in the remote location.
J Clin Anesth. 2004;16:508-516.
Mort TC. Esophageal intubation with indirect clinical tests
during emergency tracheal intubation: a report on patient
morbidity. J Clin Anesth. 2005;17:255-262.
Combes X, Sauvat S, LeRoux B, et al. Intubating laryngeal
mask airway in morbidly obese and lean patients: a comparative study. Anesthesiology. 2005;102:1106-1109.
Mort TC. Unplanned tracheal extubation outside the operating room: a quality improvement audit of hemodynamic and
tracheal airway complications associated with emergency
tracheal reintubation. Anesth Analg. 1998;86:1171-1176.
Walls RM. Rapid sequence intubation. In: Walls RM, Luten
RC, Murphy MF, et al, eds. Manual of Emergency Airway
Management. Philadelphia, PA: Lippincott, Williams &
Wilkins; 2000:8-15.
Cooper JB, Newbower RS, Long CH, McPeek B.
Preventable anesthetic mishaps: a study of human factors,
Anesthesiology. 1978;49:299-302.
Caplan RA, Posner KL, Ward RJ, Cheney FW. Adverse respiratory events in anesthesia: a closed claims analysis.
Anesthesiology. 1990;72:828-833.
Cheney RW, Posner KL, Caplan RA. Adverse respiratory
events infrequently leading to malpractice suits: a closed
claim analysis. Anesthesiology. 1991;75:932-936.
Domino KB, Posner KL, Caplan RA, Cheney FW. Airway
injury during anesthesia: a closed claims analysis.
Anesthesiology. 1991;91:1703-1711.
Chopra V, Bovill JG, Spierdi KJ. Accidents, near accidents
and complications during anesthesia: a retrospective analysis of a 10 year period in a teaching hospital. Anaesthesia.
1990;45:3-6.
Kumar V, Barcellos WA, Mehta MP, Carter JG. An analysis
of critical incidents in a teaching department for quality
assurance. A survey of mishaps during anaesthesia.
Anaesthesia. 1998;43:883-886.
Short TG, O’Regan A, Lew J, Oh TE. Critical incident reporting in an anaesthetic department quality assurance programme. Anaesthesia. 1992;47:3-7.
Sanborn KV, Castro J, Kuroda M, Thys DM. Detecting of
intraoperative incidents by electronic scanning of computerized anesthesia records. Anesthesiology. 1996;85:977-987.
Katz RJ, Lagasse RS. Factors influencing the reporting of
adverse perioperative outcomes to a quality management
program. Anesth Analg. 2000;90:344-350.
Olsson GL, Hallen B, Hambraeus-Jonzon K. Aspiration during
anaesthesia: a computer aided study of 185,358 anaesthetics. Acta Anaesthesiol Scand. 1986;30:84-92.
Beecher HK, Todd DP. A study of the deaths associated
with anesthesia and surgery base on a study of 599,548
anesthetics in ten institutions, 1948-1952. Ann Surg. 1954;
140:2-35.
Utting JE, Gray TC, Shelly FC. Human misadventure in
anaesthesia. Can Anaesth Soc J. 1979;26:472-475.
Salem MR, Baraka A. Confirmation of tracheal intubation.
In: Benumof JL, ed. Airway Management: Principles and
Practice. St. Louis, MO: Mosby; 1996:531-560.
Warner MA. Is pulmonary aspiration still an important problem in anesthesia? Curr Op Anaesthesiol. 2000;13:215-218.
Warner MA, Warner ME, Warner DO, Warner LO, Warner
EJ. Perioperative pulmonary aspiration in infants and
children. Anesthesiology. 1999;90:66-71.
Gnauck K, Lungo JB, Scalzo A, Peter J, Nakanishi A.
Emergency intubation of the pediatric medical patient: use
of anesthetic agents in the emergency department. Ann
Emerg Med. 1994;23:1242-1247.
Norwood S, Myers MB, Butler TJ. The safety of emergency
neuromuscular blockade and orotrachreal intubation in the
acutely injured trauma patient. J Am Coll Surg. 1994;179:
646-652.
39. Donahue S, Mort TC. Emergency airway management: a
strategy to improve the first pass success rate and improve
patient safety. Crit Care Med. 2004;32;A80.
40. Sugarman J, Mort TC. Efficacy of an emergency airway
management algorithm toward improving resident intubation success rate. Crit Care Med. 2004;32:A76.
41. Oliwa N, Mort TC. Airway management of the upper GI
bleeding patient: are extra measures warranted? Crit Care
Med. 2005;33:S-195421.
42. Oliwa N, Mort TC. Is a rapid sequence intubation always
indicated for emergency airway management of the upper
GI bleeding patient? Crit Care Med. 2005;33:S-195423.
43. Mort TC. The importance of a laryngoscopy strategy and
optimal conditions in emergency intubation. Anesth Analg.
2005;100:900.
44. Domino KB, Posner KL, Caplan RA, Cheney FW. Airway injury
during anesthesia: a closed claims analysis. Anesthesiology.
1999;91:1703-1711.
45. Pollard RJ, Lobato EB. Endotracheal tube location verified
reliably by cuff palpation. Anesth Analg. 1995;81:135-138.
46. McCoy EP, Russell WJ, Webb RK. Accidental bronchial intubation. An analysis of AIMS incident reports from 1988 to
1994 inclusive. Anaesthesia. 1997;52:24-31.
47. Schwartz DE, Liberman JA, Cohen NH. Confirmation of
endotracheal tube position. Crit Care Med. 1995;23:1307-1308.
48. Practice guidelines for the management of the difficult airway:
an updated report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway.
Anesthesiology. 2003;98:1269-1277.
49. Benumof JL. ASA refresher course lecture. The ASA
Difficult Airway Algorithm: an update. Presented at:
American Society of Anesthesiologists; October 9-10, 1999;
Dallas, Tex.
50. Rose EK, Cohen MM. The airway: problems and predictions
in 18,500 patients. Can J Anaesth. 1994;41:372-379.
51. Sagarin MJ, Barton ED, Chng YM, Walls RM. Airway management by US and Canadian emergency medicine residents: a
multi-center analysis of more than 6,000 endotracheal intubation attempts. Ann Emerg Med. 2005;46:328-336.
52. Combes X, Le Roux B, Suen P, et al. Unanticipated difficult
airway in anesthetized patients: prospective validation of a
management algorithm. Anesthesiology. 2004;100:1146-1150.
53. Langeron O, Semjen F, Bourgain JL, et al. Comparison of
the intubating laryngeal mask airway with the fiberoptic
intubation in anticipated difficult airway management.
Anesthesiology. 2001;94:968-972.
54. Rosenblatt WH. Preoperative planning of airway management
in critical care patients. Crit Care Med. 2004;32:S186-S192.
55. Ferson DZ, Rosenblatt WH, Johansen MJ, Osborn I,
Ovassapian A. Use of the intubating LMA-Fastrach in 254
patients with difficult-to-manage airways. Anesthesiology.
2001;95:1175-1181.
56. Sagarin MJ, Chiang V, Sakles JC, et al. Rapid sequence intubation for pediatric emergency airway management. Ped
Emerg Care. 2002;18:417-423.
57. Levitan RM, Rosenblatt B, Meiner EM, et al. Alternating day
emergency medicine and anesthesia resident responsibility
for management of the trauma airway: a study of laryngoscopy performance and intubation success. Ann Emerg
Med. 2004;43:48-53.
58. Taryle DA, Chandler JE, Good TJ, Potts DE, Sahn SA.
Emergency room intubations-complications and survival.
Chest. 1979;75:541-554.
59. Rotondo MF, Mcgonigal MD, Schwab CW, Kauder DR,
Hanson CW. Urgent paralysis and intubation of trauma
patients: is it safe? J Trauma. 1993;34:242-246.
60. Vijayakumar E, Bosscher H, Renzi FP, et al. The use of neuromuscular blocking agents in the emergency department
to facilitate tracheal intubation in the trauma patient: help
or hindrance? J Crit Care. 1998;13:1-6.
Journal of Intensive Care Medicine 22(4); 2007
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