Impact of antimicrobial prophylaxis duration on wound infection in mesh repair of incisional hernia – preliminary results of a prospective randomized trial

Summary BACKGROUND: Surgical site infections are the second most common cause of nosocomial infections. Antibacterial prophylaxis in clean surgery is controversial; nevertheless in surgery for incisional hernia with mesh it is recommended. This study was undertaken to evaluate the impact of the duration of antimicrobial prophylaxis on the rate of wound-related infections in patients undergoing repair of incisional hernia with polypropylene mesh and in whom closed suction drains were used. Evidence-based data on this subject are lacking. METHODS: A prospective randomized study was conducted to analyze 44 consecutive patients undergoing elective surgery for abdominal incisional hernia requiring polypropylene graft and subcutaneous drains. Two patients who had inadvertent bowel entry were excluded. The remaining patients were randomly allocated into two groups: Group 1 (21 patients) was given a single dose of preoperative antibiotic prophylaxis. Group 2 (21 patients) had antibiotic cover pre- and postoperatively until the drain tubes were removed. The primary outcome measure was the occurrence of wound infection as defined according to the criteria of the Center for Disease Control. RESULTS: The groups were well matched for all variables studied. The occurrence of wound infection was 19% in Group 1 and in 33.3% in Group 2. This difference did not reach statistical significance. Most infections were mild (cellulitis and infiltrate), only in two patients purulent discharge occurred. Removal of mesh was required in one of these patients in group 1. CONCLUSIONS: Regardless of the duration of antibiotic prophylaxis, no statistically significant difference was found in wound-related complications in patients undergoing elective repair of incisional hernia with mesh and in whom subcutaneous drainage was employed. Nevertheless, a trend towards a better outcome in the single dose preoperative antimicrobial prophylaxis regimen seems to emerge. Larger studies are needed to establish firm, evidence-based guidelines.