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.
Low-dose, single-shot perioperative antibiotic prophylaxis in colorectal surgery.
Reductions of frequency of administration and dosage of antibiotic agents used in colorectal surgery may lower costs and the occurrence of adverse side effects. In a prospective randomized trial we evaluated two single-short regimens, a low dose of 1 g cefotiam against a standard dose of 2 g cefotiam, both in combination with 500 mg metronidazole. The low-dose group had twice the number of patients with wound sepsis (4 of 30) than the group receiving the standard antibiotic regimen (2 of 30). Two hours after infusion, the antibiotic concentrations in samples of serum, subcutaneous fatty tissue, and colonic wall of those patients receiving 1 g cefotiam were < 1 mg/l. The concentrations after administration of 2 g cefotiam were higher, as expected, and without any adverse side effects. In conclusion, we prefer infection prophylaxis by the standard dose of 2 g cefotiam plus 500 mg metronidazole in colorectal surgery.