Repair of incisional hernia.

Because wound infection is a major cause of incisional hernia, the question posed is whether or not repairs of incisional hernias are at a higher risk for wound infection also. To answer this, we analyzed the incidence of wound infection after repair of incisional hernias during a 30 month period and compared it with the infection rate in all other clean procedures performed during the same period. All repairs of incisional hernias were performed upon patients with completely healed incisions without clinical signs of infection. Patients undergoing concomitant procedures upon the gastrointestinal tract were excluded. During the 30 month period, 995 clean operations were performed. In the 80 repairs of incisional hernias, there were 13 infections proved by culture, yielding an over-all infection rate of 16 per cent. In the remaining 915 clean procedures, there were 14 wound infections (1.5 per cent, p less than 0.0001). Of these 915 clean operations, 241 were repairs of inguinal hernias. Two infections occurred in this subgroup (0.8 per cent, p less than 0.0001, compared with repairs of incisional hernias). In patients undergoing repairs of incisional hernias with previously documented wound infections, 41 per cent had infected repairs. By comparison, only 12 per cent of patients without a prior infection had infections develop in the hernial repair (p less than 0.05). The infection rate for patients not receiving prophylactic antibiotics (21 per cent) was almost twice the rate for those receiving antibiotics (11 per cent), p = 0.07. We concluded that repair of incisional hernias has a significantly higher rate of infection than do other clean general surgical procedures. Herniorrhaphy of a wound that was previously infected is at a higher risk for reinfection, despite complete healing of the skin and absence of clinical signs of infection. Perioperative antibiotic prophylaxis may be indicated, but randomized studies are needed. For reporting and surveillance purposes, repairs of incisional hernias should not be classified as clean surgical procedures.