Abstract:Objective To identify the risk factors for intra-abdominal infection (IAI) and establish a prediction model that can accurately predict IAI after anterior resection of rectal cancer. Methods Clinical and pathological data of patients who underwent anterior resection of rectal cancer in department of gastrointestinal surgery of a hospital from December 2017 to September 2020 were collected retrospectively, independent risk factors after anterior resection of rectal cancer were screened out by univariate analysis and multivariate logistic regression analysis. Based on the independent risk factors, nomogram risk prediction model was established, and performance of the model was evaluated. Results A total of 247 patients undergoing anterior resection of rectal cancer were included in the study, 32 patients developed IAI, with an infection rate of 13.0%. Univariate and multivariate logistic regression analysis showed that diabetes mellitus (OR=4.430, 95%CI: 1.177-16.668, P < 0.05), operation time ≥ 180 minutes (OR=5.502, 95%CI: 1.459-20.752, P < 0.05), post-operative anastomotic fistula (OR=18.171, 95%CI: 4.756-69.416, P < 0.05), and post-operative pulmonary infection (OR=7.689, 95%CI: 2.143-27.593, P < 0.05) were independent risk factors for IAI after anterior resection of rectal cancer. Nomogram prediction model was established based on above results, calibration curve showed that predicted occurrence probability of the nomogram model was consistent with the actual occurrence probability, C-index value calculated by Bootstrap method was 0.945, indicating a good degree of differentiation, the area under ROC curve was 0.945 (95%CI: 0.871-0.971), and decision analysis curve showed high value. Conclusion Nomogram prediction model based on the independent risk factors of IAI after anterior resection of rectal cancer in patients can directly predict the occurrence probability of post-operative IAI.