Postcholecystectomy wound infection. The impact of prophylactic antibiotics on the epidemiology of infections.

The clinical courses of 347 patients undergoing gallbladder surgeries were monitored to study the epidemiology of postcholecystectomy wound infection in a hospital in which high-risk patients received prophylactic antibiotics. Overall, 3.8% of patients had wound infections. Patients who had positive bile cultures taken during surgery or positive intraoperative wound cultures had higher rates of infection than patients with negative cultures. However, there was a poor correlation among the bacterial isolates that were recovered from the bile or the wound surface during surgery and from postoperative infections. Antibiotic-sensitive enteric bacteria were recovered from bile samples at surgery, gram-positive organisms and enteric gram-negative bacteria were isolated from intraoperative cultures of the wound surface, and antibiotic-resistant gram-negative bacteria or enterococci were recovered from wounds that developed postoperative infections. There was a strong association between the prior receipt of prophylactic antibiotics and infections with antibiotic-resistant bacteria. Data suggest that bactibilia is still an important epidemiologic marker that identifies patients at high risk for subsequent wound infection. However, in patients who have received prophylactic antibiotics, intraoperative cultures cannot be relied on to guide the choice of empiric therapeutic antibiotics for postoperative infections. Bacteria responsible for these infections are not identified by cultures taken at the time of surgery and are often resistant to the class of antibiotics used for prophylaxis.