Pharmacokinetics of propofol infusions in patients with cirrhosis

We have compared the pharmacokinetics of propofol as an infusion in 10 control and 10 patients with cirrhosis. Anaesthesia was induced within 3-4 min during administration of an infusion of propofol 21 mg kg-1 h-1. After 5 min, the infusion was decreased in a stepwise manner to 12 mg kg-1 h-1 and subsequently 6 mg kg-1 h-1. The mean recovery time after discontinuation of the infusion was significantly longer in the cirrhotic group; however, when patients opened their eyes, blood concentrations of propofol were similar in both groups (1 micrograms ml-1). Pharmacokinetic analysis was performed from the beginning of infusion to 8 h after termination. Total body clearance was not reduced significantly in cirrhotic (1.56 (SD 0.48) litre min-1) compared with control (1.75 (0.32) litre min-1) patients. The volume of distribution at steady state was significantly greater in patients with cirrhosis than in control patients (202 (82) litre vs 121 (49) litre). However, this difference did not change terminal elimination half-life. The pharmacokinetics of propofol given by infusion to maintain general anaesthesia were not affected markedly by moderate cirrhosis.