Prophylactic oral antibiotic bowel preparation for colorectal surgery in Japan: results of a nationwide questionnaire survey.

Surgical site infections (SSIs) incur a large burden in colorectal surgery. The importance of oral antibiotic bowel preparation (OABP) in SSI prevention has been affirmed; however, the current trends in Japan are unknown. This investigated bowel preparation practices among Japanese surgeons, focusing on OABP. A nationwide online questionnaire was distributed to 456 surgeons from 412 institutions through the Japan Society for Surgical Infection. The rates of each bowel preparation protocol, mechanical bowel preparation (MBP) alone, MBP plus OABP, OABP alone, and no preparation, were as follows: 52.3 %, 43.1 %, 0.7 %, and 4.0 % for right-sided colon; 54.7 %, 44.2 %, 0.2 %, and 0.9 % for left-sided colon; 53.0 %, 46.2 %, 0.2 %, and 0.7 % for rectum; and 32.5 %, 66.0 %, 0.4 %, and 1.1 % for intracorporeal anastomosis, respectively. Combination of metronidazole and kanamycin was selected as oral antibiotic regimen in 88.1 % of respondents, and oral antibiotics were administered only on the day before surgery in 91.4 % of respondents, and this method was introduced within the last 10 years. Factors associated with OABP usage were performing over 100 colorectal cancer surgeries per year, colorectal specialization, intracorporeal anastomosis, and lower self-reported SSI rates. Although there was no significant difference, only 25 % of respondents of younger surgeons (within 10 years of the career of surgery) used OABP. Nearly half of surgeons routinely use OABP, and its adoption has grown over the past decade, although it remains less prevalent in Japan than in the United States. These finding may help optimize perioperative strategies and improve colorectal surgery outcomes in Japan.