Epidural block associated with improved long-term survival after surgery for colorectal cancer: A retrospective cohort study with propensity score matching

To investigate the effect of epidural anesthesia on the long-term prognosis of patients after selective colorectal cancer resection surgery. This was a retrospective cohort study and approved by local institution review board. Patients who underwent selective colorectal cancer resection surgery from August 2011 to December 2012 in Peking University First Hospital were enrolled. The patients were divided into general anesthesia (GA) group and combined epidural-general anesthesia (EGA) group according to anesthesia type. Primary outcome was patient's long-term survival status. Secondary outcome included the overall incidence of in-hospital complications and length of postoperative in-hospital stay. Propensity score was used to match cases between the two groups based on the probability of receiving EGA. Survival was analyzed by Kaplan-Meier analysis and compared by Log-rank test between the two groups. Multivariate Cox regression analysis was used to investigate the relationship between epidural anesthesia and