Determination of bone and fat concentrations following systemic cefamandole and regional cefuroxime administration in patients undergoing knee arthroplasty.

Five patients undergoing routine total knee replacement received standard antibiotic prophylaxis of 1000 mg of iv cefamandole and also regional administration of 750 mg of cefuroxime. Regional dosing was carried out at the start of the operation, following the application of a mid-thigh tourniquet, by administration into a foot vein. Samples of bone and fat were collected during the operation and assayed for cefuroxime and cefamandole by HPLC analysis. The mean cefuroxime bone (133.1 mg/l) and fat (88.4 mg/l) levels following regional administration were significantly higher (P less than 0.001) than the mean cefamandole bone (9.1 mg/l) and fat (9.8 mg/l) levels following systemic dosing. The possibility of administration of prophylaxis by the regional route is suggested.