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Emergency airway management in the morbidly obese patient

Christian Arbelaez, MD, MPH
Susan Bartels, MD, MPH
Calvin A Brown, III, MD, FAAEM
Section Editor
Deputy Editor
Jonathan Grayzel, MD, FAAEM


In patients presenting with acute respiratory or ventilatory failure, the emergency clinician's first responsibilities are to ensure oxygenation and secure the airway. Obesity-related anatomic and physiologic changes make airway management more difficult, and studies have shown a correlation between obesity and difficulty with endotracheal intubation [1-4].

This topic will review emergency airway management in obese and morbidly obese patients outside of the operating room. Other aspects of airway management and care of the obese patient are discussed separately. (See "Approach to the difficult airway in adults outside the operating room" and "Rapid sequence intubation for adults outside the operating room" and "Advanced emergency airway management in adults" and "Basic airway management in adults" and "Anesthesia for the obese patient" and "Obesity in adults: Overview of management".)


Definitions — The evaluation and classification of obesity is discussed in detail separately. A brief overview and aspects of obesity of particular relevance to airway management are reviewed here. (See "Obesity in adults: Prevalence, screening, and evaluation", section on 'Measurements'.)

Overweight is defined as weight above the normal range. Obesity is defined as an abnormally high percentage of body weight as fat. Body mass index (BMI) is used to distinguish between the two terms and also determines the degree of excess weight.

BMI = body weight (in kg) ÷ height (in meters) squared

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Literature review current through: Nov 2017. | This topic last updated: May 10, 2017.
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