PLASMA-LEVELS OF PIPERACILLIN AND VANCOMYCIN USED AS PROPHYLAXIS IN LIVER-TRANSPLANT PATIENTS

The pharmacokinetics of piperacillin and vancomycin used intravenously as antibioprophylaxis were measured in the plasma and bile during ort hotopic liver transplantation. Piperacillin (4 g and then 2 g every 4 h) and vancomycin (1 g and then 0.5 g every 6 h) were infused in 10 pa tients. During vascular clamping without venovenous bypass, clearance of both antibiotics decreased in relation to renal insufficiency. Duri ng the surgical procedure, volume of distribution of both drugs increa sed because of fluid redistribution. The peaks of piperacillin after f irst, second and third administrations were respectively 314, 265 and 210 mg.l-1, while trough levels were 46.5, 55.2 and 54.5 mg.l-1. The p eaks of vancomycin were 54.4,49.6 and 40.9 mg.-1, while first and seco nd trough levels were 9.5 and 12 mg.l-1. These plasma concentrations w ere quite similar to levels reported in healthy subjects despite large blood loss and fluid replacement. However, piperacillin trough concen trations (< 64 mg/l) were too low in relation to its concentration-dep endent antibacterial activity and vancomycin peak concentrations (grea ter-than-or-equal-to 40 mg/l) were slightly too high in relation to it s toxicity.