Mechanical bowel preparation combined with oral antibiotics in colorectal cancer surgery: a nationwide population-based study

Background The guidelines for reducing surgical site infection in colorectal surgery recommend mechanical bowel preparation with oral antibiotics; however, this recommendation remains controversial. This study aimed to reveal the effect of oral antibiotics combined with mechanical bowel preparation in colorectal surgery. Methods This study was a nationwide population-based retrospective study. Data between January 1, 2016, and December 31, 2018, from the Korean National Health Insurance Service database were analyzed. Patients who underwent elective colorectal cancer surgery were included. Results A total of 20,740 patients were finally included, comprising 14,554 (70.2%) who underwent mechanical bowel preparation alone and 6186 (29.8%) who underwent mechanical bowel preparation with oral antibiotics. The mechanical bowel preparation alone group was older than the mechanical bowel preparation with oral antibiotics group (65.7 ± 11.9 vs. 64.7 ± 11.8 years, p