Analysis Of Risk Factors Of Abdominal Infection After Laparoscopic Low Anterior Resection For Rectal Cancer And Establishment Of Nomogram Prediction Model

Objective:By collecting the clinical data of patients undergoing laparoscopic-assisted radical resection of rectal cancer,the risk factors of abdominal infection after laparoscopicassisted radical resection of rectal cancer were analyzed,and the risk prediction model of abdominal infection was constructed to guide the clinical decision-making of surgeons.Methods:A retrospective cohort study was conducted to collect the relevant clinical data of332 patients who underwent laparoscopic-assisted radical resection for rectal cancer in the Department of Gastrointestinal Surgery of Jiangxi Provincial People’s Hospital from September 2016 to September 2021.The patients were divided into postoperative abdominal infection group and non-postoperative abdominal infection group according to whether postoperative abdominal infection occurred.Univariate analysis was performed on the potential risk factors of postoperative abdominal infection:(1)Preoperative general information: gender,age,height,weight,BMI,ASA score,preoperative comorbity(hypertension,diabetes or COPD),hemoglobin and albumin;(2)Intraoperative conditions: operation time and intraoperative blood loss;(3)Postoperative status: p TNM stage,degree of differentiation,tumor site,neutrophil percentage(NEUT%)at day 1,3 and 7 after surgery.The potential risk factors selected by univariate analysis were analyzed by multivariate Logistic regression to obtain the independent risk factors affecting postoperative abdominal infection of rectal cancer.Then,the independent risk factors obtained were used to construct the risk prediction model for postoperative abdominal infection of rectal cancer.The R software was used to draw a line graph and conduct internal verification.The ROC curve and the area under the curve,correction curve and decision curve were drawn by R language to verify the effectiveness of the prediction model.Postoperative survival time of patients in the two groups was collected,and Kaplan-Meier survival curve was drawn to compare postoperative survival differences between the two groups.Results:A total of 332 patients undergoing peritoneal assisted radical resection for rectal cancer were collected,among which 31 patients(9.34%)developed postoperative abdominal infection.Univariate analysis showed that: ASA score ≥3 points,BMI<18.5kg/m2,complications,preoperative hemoglobin <90g/L,preoperative hypoalbumin,operative time >180min,intraoperative blood loss >100ml,p TNM stage III,T stage,and NEUT% on the third day after surgery had statistical significance(P<0.05).It is a risk factor for abdominal infection after rectal cancer surgery.Multivariate logistic regression analysis showed that ASA score ≥3,BMI<18.5kg/m2,complications,preoperative low albumin,p TNM stage III,and NEUT% on the third day after surgery were independent risk factors for postoperative abdominal infection of rectal cancer.The selected independent risk factors were used to construct and verify the risk prediction model of postoperative abdominal infection of rectal cancer.The area under ROC curve was 0.905(95%CI:0.855-0.956).The internal verification of Bootstrap method shows that the C index is 0.905,indicating that the model has good predictive value.Kaplan-Meier survival analysis showed that there was a difference in postoperative survival between the two groups.The survival time of the non-abdominal infection group was longer than that of the abdominal infection group,and the difference was statistically significant(P=0.005).Conclusion:In this study,it was concluded that ASA score ≥3,BMI<18.5kg/m2,complications,preoperative low albumin,p TNM stage III,and NEUT% on the third day after surgery were independent risk factors for postoperative abdominal infection of rectal cancer.The above independent risk factors were included in the construction of a risk prediction model for postoperative abdominal infection of rectal cancer and the model efficacy was verified.Kaplan-Meier survival analysis verified that the non-abdominal infection group had a better prognosis than the abdominal infection group.The establishment of this model provides good reference and clinical practice guidance for clinicians to make clinical decisions.It will be more conducive to the prevention and control of postoperative abdominal infection in patients with rectal cancer undergoing laparoscopic surgery,so as to improve the prognosis of patients and bring considerable benefits to patients.