Pharmacokinetics and pharmacodynamics of cefoperazone-sulbactam in patients on continuous ambulatory peritoneal...

This study was conducted to determine the pharmacokinetics of the fixed combination antibiotic cefoperazone-sulbactam in patients receiving continuous ambulatory peritoneal dialysis (CAPD). In addition, the pharmacodynamic profile of this combination was determined by the use of mean bactericidal titers against selected bacterial strains. Six noninfected CAPD patients were given a fixed dose of cefoperazone (2 g) and sulbactam (1 g) either intravenously or intraperitoneally over 10 min in a randomized, two-way crossover fashion. The mean peak cefoperazone concentration in serum after intravenous administration was 280.9 micrograms/ml. The mean peak concentration in serum after intraperitoneal cefoperazone administration was 38.9 micrograms/ml and occurred 2 to 4 h postdose. The mean peak sulbactam concentration in serum after intravenous administration was 82.2 micrograms/ml. The mean peak concentration in serum after intraperitoneal sulbactam administration was 24.4 micrograms/ml and occurred at 6 h. The absolute bioavailability of the intraperitoneal dose was 61% for cefoperazone and 70% for sulbactam. Cefoperazone total body and renal clearances were unaffected by renal failure and dialysis. However, both clearance values for sulbactam were reduced markedly. Only intraperitoneal dosing provided peak inhibitory and bactericidal titers in dialysate for all organisms tested. Intravenous dosing provided satisfactory dialysate titers only for very susceptible bacterial strains. End-stage renal disease and CAPD do not alter cefoperazone pharmacokinetics; however, sulbactam dosing may need to be adjusted.