Obesity and Anesthetic Pharmacology: simulation of target-controlled infusion models of propofol and remifentanil

The prevalence of obesity is increasing and the number of surgeries of obesity-induced diseases and obesity itself is on the rise. Besides the comorbidities of obesity, pharmacokinetic (PK) and pharmacodynamic (PD) changes in obese patients make it difficult to control the appropriate dose of anesthetic agents. Factors that affect the pharmacokinetic changes in obese individuals includes increase of adipose tissue, increase of lean body weight, increase of extracellular fluid and increase of cardiac output. These physiologic and body compositional changes affect the changes of PKPD parameters. Increased central volume of distribution and clearance affect the plasma concentration of propofol and remifentanil in obese population. Obese can affect even pharmacodynamic properties of EC50 or Ke0. Simulation of target-controlled infusion based on the PKPD models in which obese populations is included help physicians understand the effect of obese on the PKPD changes of anesthetic drugs.