The bacteriology of primary wound sepsis in potentially contaminated abdominal operations: the effect of irrigation, povidone-iodine and cephaloridine on the sepsis rate assessed in a clinical trial.

Two hundred and nine potentially contaminated abdominal operations were randomly allocated to prophylaxis with a single dose of 1 g cephaloridine intraincisionally, irrigation of the wound at the end of the operation with saline or spraying of the wound with povidone-iodine. In high risk operations (ileocolorectal or those in obese patients) the rate of major wound sepsis in those protected by cephaloridine was 3.8% compared with 13.2% in the irrigation and 16.7% in the povidone-iodine groups. In low risk operations no significant differences in sepsis rates were found. Bacteriological studies of incised organs, subcutaneous fat and pus showed that the majority of wound infections arose from endogenous sources. The outstanding problem remains that of prevention of contamination of the abdominal wall during surgery.