11 - Effects of obesity on anesthetic agents

Summary

This chapter reviews several factors that affect pharmacokinetics (PK) and pharmacodynamics (PD) of anesthetic agents in the obese population and specifies certain dosing scalars. It presents the current knowledge of obesity's effects on the clinical pharmacology of specific drugs that produce or reverse anesthesia. In a PK study in which patients received thiopental to induce anesthesia, absolute total body clearance was significantly larger in the obese than in normal weight patients. In hemodynamically unstable morbid obesity (MO) patients or patients with obesity cardiomyopathy, anesthesic induction with etomidate may be a better choice than either thiopental or propofol. Opioids effectively block somatic and autonomic responses during surgery. Target-controlled infusion (TCI), an anesthetic dosing technique developed during the last decades, allows interactive drug dosing on the basis of common PK-PD models. Sugammadex can reverse profound neuromuscular blockade.