A controlled trial of parenteral prophylactic gentamicin therapy in biliary surgery

This trial has investigated the value of gentamicin therapy in patients requiring biliary surgery. One hundred consecutive patients were randomly allocated to receive either gentamicin or no antibiotic. Post-operative infection was assessed by an independent observer. Cultures and gentamicin assays were performed on bile and blood sampled during and after operation. The minimum inhibitory concentrations of gentamicin were measured with isolated bacterial. In 80 per cent of patients biliary organisms were inhibited by 2 mug/ml of gentamicin. Twice this concentration was found in the serum at operation in 88 per cent, but in the bile in only 18 per cent. Nevertheless, gentamicin lowered the incidence of bacteria in the bile from 42 to 25 per cent. There was a reduction in wound sepsis from 21 to 6 per cent (P less than 0-05). Bacteriaemia was demonstrated in only 1 patient receiving gentamicin compared with 5 controls and 1 death occurred from endotoxaemia in the control group. These data suggest that gentamicin will reduce the morbidity of biliary surgery, particularly in patients in whom the bile is infected at operation.