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.
Tinidazole and doxycycline compared to doxycycline alone as prophylactic antimicrobial agents in elective colorectal surgery.
Forty-two patients admitted for elective colorectal surgery were given tinidazole and doxycycline or doxycycline alone as prophylactic antimicrobials in a double-blind study. There was altogether one abdominal wound infection (2.4%), and one patient developed a perineal fistula three months after the operation. No significant difference in postoperative infections between the two groups could be demonstrated. It is concluded that doxycycline seems effective in reducing wound sepsis after operations on the large intestine and that additional administration of tinidazole will yield little in prophylaxis.