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.
Value of oral antibiotic prophylaxis in colorectal surgery.
A total of 169 patients undergoing colorectal surgery were randomly allocated to receive either gentamicin plus metronidazole or oral ciprofloxacin plus metronidazole as prophylaxis; they were also allocated to receive cover for 1 or 3 days. Twenty-eight patients (17 per cent) developed postoperative wound infections. The proportion of patients with wound infections and other infective complications was significantly less (P < 0.02) in those receiving oral ciprofloxacin. Cover for 3 days was no better than that for only 1 day. Oral ciprofloxacin for prophylaxis may offer advantages in efficacy and ease of administration compared with parenteral antibiotics.