The effect of surgical starting time on elective colorectal cancer surgery: A propensity score matching analysis

The purpose of the current study is to analyze whether surgical starting time affects the short-term outcomes of elective colorectal cancer (CRC) surgery. We retrospectively collected CRC patients who underwent elective surgery from Jan 2008 to Jan 2021 in a single clinical center. The effect of surgical starting time (morning surgery vs afternoon surgery, day surgery vs night surgery) on elective CRC surgery was analyzed using propensity score matching (PSM). A total of 6783 patients were included in the current study. There were 5751 patients in day surgery group and 1032 patients in night surgery group, and there were 2920 patients in morning surgery group and 2831 patients in afternoon surgery group. After 1:1 ratio PSM, there were no significant difference in terms of the baseline information (P > .05). Day surgery group had longer operation time (P = .000) and longer hospital stay (P = .029) than night surgery group after PSM. Morning surgery group had longer operation time than afternoon surgery group before PSM (P = .000) and after PSM (P = .000). Univariate and multivariate analysis of the total of 6783 patients were conducted to find predictors of complications, and found that night surgery was a predictor of major complications (P = .002, OR = 1.763, 95% CI = 1.222-2.543) but not a predictor of overall complications (P = .250, OR = 1.096, 95% CI = 0.938-1.282). Night surgery is a predictor of major complications after elective CRC surgery, therefore, surgeons should be careful when operating at night.