Preanesthesia medical evaluation of the obese patient
- Roman Schumann, MD
Roman Schumann, MD
- Associate Professor of Anesthesiology
- Tufts University School of Medicine
As the prevalence of obesity increases worldwide, an increasing number of obese surgical patients will require anesthesia. Planning for anesthesia must take into account both physiologic changes caused by obesity, and the presence of comorbid conditions associated with obesity; consequently, the preanesthetic evaluation should determine and evaluate the relevant issues for the individual patient.
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 (WHO) and the National Institutes of Health (NIH) have adopted a classification of obesity defined by BMI:
●Overweight – BMI ≥25 to 29.9 kg/m2.
●Obesity – BMI ≥30 kg/m2.
●Obesity class 1 – BMI of 30 to 34.9 kg/m2.
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- THE "OBESITY PARADOX" IN ANESTHESIA
- PREOPERATIVE EVALUATION
- Patients with known comorbidities
- Screening for comorbidities
- Airway assessment
- - Predictors of airway difficulty
- PREOPERATIVE PREPARATION
- Positive airway pressure therapy
- Patients with previous weight-loss surgery
- Ambulatory versus inpatient surgery
- SUMMARY AND RECOMMENDATIONS