Effect of enteral versus parenteral feeding on hepatic blood flow and steady state propofol pharmacokinetics in ICU patients.
OBJECTIVE
The main objective of this study was to evaluate the effect of switching from parenteral to enteral feeding on liver blood flow and propofol steady-state blood concentrations in patients in the intensive care unit (ICU).


METHODS
Steady-state blood concentrations of propofol were measured in eight ICU patients before (on days D -3, D -2, and D -1) and after (on days D + 1, D + 2, and D + 3) switching from parenteral to enteral feeding (on day DO). All patients received a continuous intravenous infusion of propofol (4.5 mg x kg(-1) x h(-1)) from several days before the start of the study, continuing throughout the experimental period. Hepatic blood flow was estimated by measuring steady-state D-sorbitol hepatic clearance.


RESULTS
Hepatic blood flow was high and was not affected by switching from parenteral to enteral feeding: 33 +/- 8 ml x min(-1) x kg(-1) (mean +/- SD) and 33 +/- 10 ml min(-1) x kg(-1) on D -3 and D -1, respectively, as compared to 37 +/- 11 ml x min(-1) kg(-1) and 34 +/- 8 ml x min(-1) x kg(-1) on days D + 1 and D + 3, respectively. Systemic clearance of propofol was much higher than liver blood flow with average values on the six observation days ranging from 74.0 to 81.2 ml x min(-1) x kg(-1) and was not affected by switching from parenteral to enteral feeding.


CONCLUSIONS
Liver blood flow and systemic clearance of propofol were not affected by switching from parenteral to enteral feeding in the eight ICU patients studied. Extrahepatic clearance accounted for at least two thirds of the overall systemic clearance of propofol.
Van Brandt
N
N
Laboratory of Pharmacokinetics, School of Pharmacy, UCL/FATC 7355, Brussels, Belgium.
Hantson
P
P
Horsmans
Y
Y
Mahieu
P
P
Verbeeck
R K
RK
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D003422:Critical Care / Q000379:methods*; D004750:Enteral Nutrition; D018565:Food-Drug Interactions; D006801:Humans; D006993:Hypnotics and Sedatives / Q000493:pharmacokinetics*; D008099:Liver / Q000098:blood supply*; D008137:Longitudinal Studies; D008875:Middle Aged; D010288:Parenteral Nutrition; D015742:Propofol / Q000493:pharmacokinetics*; D013152:Splanchnic Circulation / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
D006993:Hypnotics and Sedatives; D015742:Propofol