STANDARDIZING PRACTICE
Defining the Difficult Airway
W
hat's a "difficult airway" anyway?
Although there's no formal, standard
definition, the American Society for
CONSENSUS DESCRIPTION
The ASA task force has
provided a way to define and
describe difficult airways in
patient documentation.
Anesthesiologists Task Force on the Difficult Airway
sought to create one based on the literature and a
consensus involving consultants, experts and members practicing nationwide. This process devised a
streamlined definition: "The clinical situation in
which a conventionally trained anesthesiologist experiences difficulty with face mask ventilation of the
upper airway, difficulty with tracheal intubation, or both." The task force suggests further describing a
difficult airway in case documentation these ways:
1. Difficult facemask or supraglottic airway (SGA) ventilation. This includes situations in which,
despite use of a laryngeal mask airway, intubating LMA and laryngeal tube, the anesthesia provider
can't provide adequate ventilation. Issues may include one or more of the following: inadequate mask or
SGA seal, excessive gas leak, or excessive resistance to the ingress or egress of gas. Physical signs
include the following: absent or inadequate chest movement, absent or inadequate breath sounds, auscultatory signs of severe obstruction, cyanosis, gastric air entry or dilatation, decreasing or inadequate
oxygen saturation (SpO2), absent or inadequate exhaled carbon dioxide, absent or inadequate spirometric measures of exhaled gas flow, and hemodynamic changes associated with hypoxemia or hypercarbia (hypertension, tachycardia, and arrhythmia, for example).
2. Difficult SGA placement. SGA placement requires multiple attempts, in the presence or absence of
tracheal pathology.
3. Difficult laryngoscopy. It's not possible to visualize any portion of the vocal cords after multiple
attempts at conventional laryngoscopy.
4. Difficult tracheal intubation. Multiple attempts are required, whether or not tracheal pathology is
present.
5. Failed intubation. Endotracheal tube placement fails after multiple attempts.
— Robert Caplan, MD
J A N U A R Y 2013 | S U P P L E M E N T
TO
O U T PAT I E N T S U R G E R Y M A G A Z I N E
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