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.
Amoxycillin and clavulanic acid versus cefotaxime and metronidazole as antibiotic prophylaxis in elective colorectal resectional surgery.
In a prospective randomised controlled trial, amoxycillin plus clavulanic acid was compared to a combination of cefotaxime and metronidazole as prophylactic antibiotics in 164 patients who underwent elective colorectal resectional surgery. Wound infection occurred in 15 patients (9.1%) and deep surgical infection in 4 (2.4%). Seven cases of wound infection and 2 cases of deep infection occurred in the amoxycillin plus clavulanic acid arm, while 8 cases of wound infection and 2 cases of deep infection occurred in the cefotaxime plus metronidazole arm. Eighty-eight percent of infections occurred in patients who had low anterior resection or abdominoperineal resection of the rectum. Both the amoxycillin plus clavulanic acid and the combination of cefotaxime and metronidazole offer the same degree of protection against post-operative infection. The use of amoxycillin plus clavulanic acid as antibiotic prophylaxis is recommended because of its easier use and cheaper cost.