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Approach to the difficult airway in adults outside the operating room

Calvin A Brown, III, MD, FAAEM
Section Editor
Deputy Editor
Jonathan Grayzel, MD, FAAEM


Most emergency department (ED) endotracheal intubations are performed on an emergent basis (ie, intubation cannot be delayed or avoided). The universal emergency airway management algorithm provides the recommended approach to emergency intubation (algorithm 1 and algorithm 2) [1,2]. This approach is based on two key assessments of the patient prior to intubation.

The first assessment is to determine if the patient has a "crash" airway (ie, presenting in extremis with little or no cardiovascular or respiratory activity, and unlikely to respond to insertion of a laryngoscope). If so, the crash airway algorithm is used (algorithm 3) [2].

If the patient is not a crash airway, the next step is to determine if the patient presents a difficult airway. This requires assessment of specific patient attributes to predict the likelihood of difficulty in performing any of the major procedures in airway management: direct laryngoscopy and intubation, bag-mask ventilation, surgical airway management, and ventilation using an extraglottic airway.

If the patient is felt to be neither a crash nor a difficult airway, then rapid sequence intubation is the recommended method for managing the airway. (See "Rapid sequence intubation for adults outside the operating room".)

The decision that the patient presents with a difficult airway is a critical determinant of the best approach to intubation. This topic review will discuss assessment and management of the difficult airway in adults. Other aspects of airway management, including pediatric airway management, are discussed separately. (See "The difficult pediatric airway" and "Emergency endotracheal intubation in children" and "Basic airway management in adults" and "Advanced emergency airway management in adults" and "Rapid sequence intubation for adults outside the operating room".)

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Literature review current through: Nov 2017. | This topic last updated: May 31, 2017.
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