Penetration of cefoperazone into ascites

The pharmacokinetics of cefoperazone was studied in eleven cirrhotic patients with ascites after i.v. administration of a single dose of 15 mg.kg-1 (n = 7) or after three doses of 15 mg.kg-1 given at 12 h intervals (n = 4). The concentrations of cefoperazone in serum and ascitic fluid were determined by HPLC. The peak serum cefoperazone concentration after a single i.v. injection of 15 mg.kg-1 was 96.0 mg.l-1. The serum elimination half-life was longer (5.0 h) than in normal subjects. The penetration of cefoperazone into ascites was satisfactory (32.3% and 58.3% after single and repeated injections, respectively). Ascitic fluid concentrations of cefoperazone exceeded 5.4 mg.ml-1 from 0.5 to 6 h after the single i.v. injection, levels which are well above the MIC of most pathogens found in spontaneous bacterial peritonitis. Adjustment of the dose of cefoperazone in cases of severe hepatic insufficiency does not appear to be necessary provided that renal function is normal.