Clinical Pharmacology of Intravenous and Intraperitoneal Aminoglycoside Antibiotics in the Prevention of Wound Infections

Abstract

Seventeen patients had intraoperative peritoneal lavage with a solution containing one gram of kanamycin in 200 ml of 0.9% NaCl. The solution was removed by suction at two or five minutes. Venous blood samples were obtained at 15 minute intervals for two hours following lavage. Despite diligent attempts, an average of only 60% of the solution was recovered by suction. The peak concentration of kanamycin in serum correlated directly with the kanamycin dose (p < 0.025). In six patients lavaged for five minutes, peak absorption occurred at 15 minutes with serum concentrations of 20.3 ± 2.0 μg/ml. In five patients lavaged for two minutes insignificantly (p > 0.1) lower peak serum concentrations (15.3 ± 1.8 μg/ml) occurred at 15 minutes. Six additional patients had peak kanamycin serum concentrations which occurred at 75 minutes and reached 23.2 and 24.0 μg/ml in two patients. In three patients who received intravenous gentamicin prior to surgery, nine paired serum and peritoneal fluid samples obtained during three hours preceding lavage showed no significant differences in gentamicin concentrations (p > 0.5). These pharmaco-kinetic data demonstrate the penetration of parenterally administered aminoglycosides into intraoperative peritoneal fluid. Kanamycin lavage for wound prophylaxis should be used cautiously and should be abandoned in patients who have renal impairment where prolonged toxic serum concentrations could develop.