Which Intraoperative Monitors are Essential for the Obese Surgical Patient?

Abstract

There is limited evidence on anesthetic management of obese and in particular of morbidly obese patients. Little is known of the pharmacokinetics (PK) and pharmacodynamics (PD) of anesthetic agents in obese. The anesthetic conduct is mainly adapted from that of normal weight subjects. Furthermore the modest knowledge acquired on obese patients is used to infer strategies for morbidly obese. The profound changes in body composition and organ function impose strict monitoring preoperatively. Monitoring is therefore the key to fill the gap between knowledge and patient safety. This chapter will discuss the controversial issue of what anesthetic monitor should be regarded as essential. Although formal recommendations are lacking, modifications in pathophysiology imposed by various degrees of obesity, along with modifications in PK and PD, suggest the need for additional monitoring. The rationale and available evidence are discussed.