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.
Cefoxitin versus erythromycin, neomycin, and cefazolin in colorectal operations. Importance of the duration of the surgical procedure.
Perioperative parenteral cefoxitin was compared with oral erythromycin, neomycin and parenteral cefazolin in a prospective, double-blind, randomized evaluation of 119 patients undergoing colorectal operations. Patients receiving cefoxitin had a higher wound infection rate than patients receiving erythromycin-neomycin-cefazolin (12.5% v 3.2%, respectively, p = .06). A direct correlation existed between the duration of the operation and the infection rate. Cefoxitin prophylaxis was as effective as erythromycin-neomycin-cefazolin in patients undergoing surgical procedures of 4 hours or less (infection rates of 4.8% and 4.0%, respectively). However, for surgical procedures lasting more than 4 hours, 5 of 14 patients (37.5%) receiving cefoxitin developed a wound infection v 0 of 13 patients receiving erythromycin-neomycin-cefazolin (p less than .05). It is speculative as to whether frequent two-gram doses of cefoxitin given during the operation would provide prophylaxis equivalent to erythromycin-neomycin-cefazolin.