Objective    To investigate pharmacokinetics of propofol administered by target-controlled infusion (TCI) in patients with liver failure.     Methods    Nine ASA Ⅳ patients with liver failure aged 32-53 years

weighing 60-81 kg

who would undergo liver transplantation

were enrolled in this study

and nine ASA Ⅰ-Ⅱ patients aged 22-59 years

weighing 46-70 kg

who would undergo selective upper abdominal surgery

were as control group. In the two groups

propofol was administered for 60 min by TCI via Graseby 3500 infusion pump incorporated with Stelpump software

while the target plasma propofol concentration was set at 2.5 μg/ml. Arterial blood samples were taken immediately before and at 2

5

10

20

30

40

50

60

62.5

65

70

75

80

85

90 min after the start of propofol infusion

and the plasma concentrations of propofol were measured by using gas chromatography-mass spectrometry. The data obtained were analyzed by DAS pharmacokinetic software.     Results    The central volume of distribution (Vc)

apparent volume of distribution (Vp) and total clearance (CL) were significantly larger in liver transplantation group than those in control group (P0.05)

but no significant differences in distribution half-time (T

1/2

α)

elimination half-time (T

1/2

β) were found between the two groups.     Conclusion    The volume of distribution and clearance of propofol increased in the patients with liver failure

which will not lead to drug accumulation and long duration of action.