Short-term intravenous antimicrobial prophylaxis for elective rectal cancer surgery: results of a prospective randomized non-inferiority trial

PURPOSE: To investigate the non-inferiority of postoperative single-dose intravenous antimicrobial prophylaxis to multiple-dose intravenous antimicrobial prophylaxis in terms of the incidence of surgical site infections (SSIs) in patients undergoing elective rectal cancer surgery by a prospective randomized study. METHODS: Patients undergoing elective surgery for rectal cancer were randomized to receive a single intravenous injection of flomoxef (group 1) or five additional doses (group 2) of flomoxef after the surgery. All the patients had received preoperative oral antibiotic prophylaxis (kanamycin and erythromycin) after mechanical cleansing within 24 h prior to surgery, and had received intravenous flomoxef during surgery. RESULTS: A total of 279 patients (including 139 patients in group 1 and 140 in group 2) were enrolled in the study. The incidence of SSIs was 13.7 % in group 1 and 13.6 % in group 2 (difference [95 % confidence interval]: −0.2 % [−0.9 to 0.7 %]). CONCLUSION: The incidence of SSIs was not significantly different in patients undergoing elective rectal surgery who were treated using a single dose of postoperative antibiotics compared to those treated using multiple-dose antibiotics when preoperative mechanical and chemical bowel preparations were employed.