Pharmacokinetic profile of propofol after a single-dose injection during general anesthesia in Japanese adults.

Abstract

To determine the pharmacokinetic parameters of propofol after a single-dose injection in Japanese adults. This study was carried out in adult patients who underwent minor surgery under general anesthesia with sevoflurane. We injected 1.0, 1.5, or 2.0 mg.kg(-1) of propofol at a constant rate using a syringe pump. Arterial blood samples were taken for 480 min after the administration of propofol. The whole-blood concentration of propofol was determined with gas chromatography, and a time-blood concentration curve was analyzed by a two-compartment open-model analysis and a model-independent analysis. The half-lives of the central and peripheral compartment ( t(1/2)alpha and t(1/2)beta) were 2.26 +/- 0.69 and 47.9 +/- 22.1 min, respectively. The volume of the central compartment (V(c)) was 0.582 +/- 0.170 l.kg(-1), and the apparent volume of distribution at a steady state (V(dss)) was 2.62 +/- 1.06 l.kg(-1). The total body clearance (Cl) and mean residence time (MRT) were 53.7 +/- 11.9 ml.min(-1).kg(-1) and 98.1 +/- 16.4 min, respectively. Among the pharmacokinetic parameters determined in Japanese adults, t(1/2)alpha, t(1/2)beta, and Vc were similar, V(dss) was smaller, and Cl was larger, as compared with values in Caucasians. These findings suggest that propofol could be eliminated well during minor surgery in Japanese adults.