The predictive value of bacterial contamination at operation in post-operative wound sepsis.

Wounds of 53 surgical patients were studied prospectively both clinically and bacteriologically. There were 26 males and 27 females with a mean age of 38.3 yr. Culture of fascia-deep wound swabs at closure of wound at the end of operation was related to culture if postoperative wound infection occurred. Overall wound infection rate was 15.1% with an infection rate for clean wounds of 3.7% being lowest and the dirty wound infection rate of 60% being highest. Pathogenic organisms in seven of eight infected wounds had been isolated at wound closure while in one instance they were different from organisms in the wound at closure. Risk of development of subsequent infection was significant if enteric organisms rather than Staphylococcus were isolated from the wound at closure. Wounds that had negative culture at the end of operation had no post-operative infection. The study underlines the importance of bacteriological analysis of wounds at the end of operation in identifying those at risk of post-operative infection and the probable causative pathogenic organisms. This will be useful in the choice of prophylactic antibodies for treatment of high-risk patients.