Antibiotics covering aerobic and aerobic bacteria should be delivered orally and intravenously prior to colorectal surgery.  Antibiotics delivered within this framework will reduce the risk of postoperative SWI by at least 75%.  Further research is required to establish the optimal timing and duration of dosing, and frequency of longer-term adverse effects such as Clostridium difficile pseudomembranous colitis.
Sulbactam/ampicillin compared with cefoxitin for chemoprophylaxis in elective colorectal surgery.
In a prospective, randomized, comparative study, patients undergoing elective major colorectal surgery received four six-hour doses of either sulbactam (a beta-lactamase inhibitor) with ampicillin (1 gm with 1 gm), or cefoxitin (2 gm) commencing at induction of anesthesia. The groups were well matched for age, sex, diagnosis, and surgical procedures. Three patients in the sulbactam group (N = 44), and four in the cefoxitin group (N = 48) developed significant wound sepsis. Minor wound sepsis occurred in an additional four sulbactam patients, and in five cefoxitin patients. There was no difference between the groups in deep sepsis or anastomotic leak rates (sulbactam, four patients; cefoxitin, seven patients). No serious side effects were recorded in either group. These results suggest that sulbactam combined with ampicillin provides a safe, effective alternative to cefoxitin for prophylaxis in colorectal surgery.