Systemic absorption of bacitracin after peritoneal lavage

Nine patients underwent intraoperative peritoneal lavage with a solution containing 50,000 units of bacitracin in 200 ml of 0.9 per cent sodium chloride. The solution was removed by suction at 2 or 5 minutes, and venous blood samples were obtained at 15 minute intervals for 2 hours after lavage. Concentrations of bacitracin in serum were determined by agar diffusion assay. In the majority of patients, peak concentrations of bacitracin in serum occurred by 15 minutes post lavage. The mean peak serum concentration was 3.8 units/ml, which exceeds peak concentrations after intramuscular injection of 50,000 units. Due to potential nephrotoxicity, bacitracin should be used cautiously in peritoneal lavage solutions and should be abandoned in patients who have renal impairment in whom prolonged elevated serum concentrations could develop.