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

Abstract

Purpose. To determine the pharmacokinetic parameters of propofol after a single-dose injection in Japanese adults.

Methods. 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.

Results. The half-lives of the central and peripheral compartment (t _1/2α and t _1/2β) 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.

Conclusions. Among the pharmacokinetic parameters determined in Japanese adults, t _1/2α, t _1/2β, 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.