Does every morbidly obese patient need a complete preoperative workup?

Abstract

The perioperative management of morbidly obese patients is an intimidating challenge for anesthesiologists. Due to the high frequency of many organ system abnormalities, do all morbidly obese patients require a full workup preoperatively? In other words, in the absence of clinical signs or symptoms of pathology, are clinicians obligated to perform testing for cardiac function, coronary artery patency, obstructive sleep apnea, pulmonary, hepatic and renal disease and other common obesity-related diseases that may impact surgical and anesthetic outcome? There is currently insufficient evidence to clearly support either a comprehensive approach, which may be expensive, inefficient and possibly harmful or a workup consistent with the same standard of care as non-obese patients. Nevertheless, there is acceptable safety data and expert opinion that supports a targeted symptom-based approach to preoperative evaluation. For moderate or severe risk procedures, all morbidly obese patients should have a comprehensive metabolic panel and chest X-ray. An EKG is reasonable, but only necessary in the presence of known risk factors. Anesthesiologists must have a high index of suspicion for common obesity-related problems such as obstructive sleep apnea, atrial fibrillation, heart failure, coronary artery disease, decreased functional residual capacity, poor glycemic control and gastro-esophageal reflux and provide appropriate screening questions during the preanesthetic history and physical. A comprehensive workup with testing is likely unnecessary and may not improve outcomes.