Skeletal muscle kinetics of propofol in anaesthetized sheep: effect of altered muscle blood flow.
1. The kinetics of propofol were studied in vivo in a skeletal muscle bed of the hindlimb of the anaesthetized sheep at normal and low rates of blood flow. 2. Propofol kinetics in muscle were determined during and after a 20-min i.v. infusion of propofol (10 mg min-1) via paired arteriofemoral venous blood sampling. One-and-a-half hours later, the study was repeated but with a concurrent left femoral artery infusion of adrenaline (0.004 mg min-1) to lower the muscle blood flow by vasoconstriction. 3. Muscle blood flow in the low flow state was 28% of that in the normal state. The kinetics were poorly described by a single flow-limited compartment model, but were better described by a model with a flow-limited component and a deeper distribution component. There were no significant differences in muscle retention of propofol between normal and low flow states. 4. There was an apparent arteriovenous shunt of approximately 24% of total muscle blood flow for the low flow state, but not for the normal blood flow state.
Zheng
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University of Adelaide/Royal Adelaide Hospital, North Terrace, Adelaide, SA 5005, Australia. da.zheng@adelaide.edu.au
Upton
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Martinez
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A
D000322:Adrenergic Agonists / Q000494:pharmacology; D018686:Anesthetics, Intravenous / Q000493:pharmacokinetics*; D000818:Animals; D019540:Area Under Curve; D004837:Epinephrine / Q000494:pharmacology; D006439:Hemodynamics; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D015233:Models, Statistical; D018482:Muscle, Skeletal / Q000378:metabolism*; D009132:Muscles / Q000098:blood supply* / Q000187:drug effects*; D010101:Oxygen Consumption / Q000187:drug effects; D015742:Propofol / Q000493:pharmacokinetics*; D012756:Sheep; D013997:Time Factors
D000322:Adrenergic Agonists; D018686:Anesthetics, Intravenous; D015742:Propofol; D004837:Epinephrine