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Anesthesia for the obese patient

Roman Schumann, MD
Section Editor
Stephanie B Jones, MD
Deputy Editor
Marianna Crowley, MD


As the prevalence of obesity increases worldwide, an increasing number of obese surgical patients will require anesthesia. Obesity is typically defined by body mass index (BMI), the ratio of weight (in kilograms) to the square of height (in meters) (calculator 1). In adults, the World Health Organization and the National Institute of Health define obesity as a BMI ≥30 kg/m2.

This topic reviews the changes in anatomy and physiology in obese patients that affect anesthetic management, anesthetic drug dosing in obesity, and planning the anesthetic (type of anesthesia, equipment, appropriate monitoring, and analgesic plan) as it differs from patients with normal BMI. Preoperative medical evaluation of obese patients, the impact of obstructive sleep apnea on anesthetic management, and general principles and techniques in anesthesia are discussed separately.

(See "Preanesthesia medical evaluation of the obese patient".)

(See "Surgical risk and the preoperative evaluation and management of adults with obstructive sleep apnea".)

(See "Intraoperative management of adults with obstructive sleep apnea".)

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Literature review current through: Dec 2017. | This topic last updated: Sep 11, 2017.
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