Incidence and risk factors of surgical site infection following colorectal surgery in China: a national cross-sectional study

PURPOSES: Surgical site infection (SSI) after colorectal surgery is a frequent complication associated with the increase in morbidity, medical expenses, and mortality. To date, there is no nationwide large-scale database of SSI after colorectal surgery in China. The aim of this study was to determine the incidence of SSI after colorectal surgery in China and to further evaluate the related risk factors. METHODS: Two multicenter, prospective, cross-sectional studies covering 55 hospitals in China and enrolling adult patients undergoing colorectal surgery were conducted from May 1 to June 30 of 2018 and the same time of 2019. The demographic and perioperative characteristics were collected, and the main outcome was SSI within postoperative 30 days. Multivariable logistic regressions were conducted to predict risk factors of SSI after colorectal surgery. RESULTS: In total, 1046 patients were enrolled and SSI occurred in 74 patients (7.1%). In the multivariate analysis with adjustments, significant factors associated with SSI were the prior diagnosis of hypertension (OR, 1.903; 95% confidence interval [CI], 1.088–3.327, P = 0.025), national nosocomial infection surveillance risk index score of 2 or 3 (OR, 3.840; 95% CI, 1.926–7.658, P < 0.001), laparoscopic or robotic surgery (OR, 0.363; 95% CI, 0.200–0.659, P < 0.001), and adhesive incise drapes (OR, 0.400; 95% CI, 0.187–0.855, P = 0.018). In addition, SSI group had remarkably increased length of postoperative stays (median, 15.0 d versus 9.0d, P < 0.001), medical expenses (median, 74,620 yuan versus 57,827 yuan, P < 0.001), and the mortality (4.1% versus 0.3%, P = 0.006), compared with those of non-SSI group. CONCLUSION: This study provides the newest data of SSI after colorectal surgery in China and finds some predictors of SSI. The data presented in our study can be a tool to develop optimal preventive measures and improve surgical quality in China. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12879-020-05567-6.