Comparison Between End-to-side and Side-to-side Anastomosis After Laparoscopic Right Hemicolectomy

All patients will be received a laparoscopic right hemicolectomy by three experienced colorectal surgeons and randomly divided into two groups according to the method of anastomosis: - the end-to-side anastomosis group and the side-to-side anastomosis group. After the surgery, enhanced recovery program will be implemented. The primary endpoint is the cumulative recovery rate according to the method of anastomosis. The cumulative recovery rate is defined as the percentage of patients who are satisfied with all aspects of recovery time, including i) tolerance of diet for 24 hours, 2) analgesic-free (oral or intravenous (IV) analgesic drugs not necessary after cessation of patient-controlled analgesia (PCA)), 3) safe ambulation (ambulation of 600m without assistance), 4) afebrile status without major complications (fever was defined as body temperature greater than 37.2°C at axilla). Secondary endpoints are postoperative hospital stay, complications, the failure rate of the enhanced recovery program, and the readmission rate within 1 month after surgery. The expected cumulative recovery rate in postoperative day 7 is 90% in the end-to-side anastomosis group and 70% in the side-to-side anastomosis group. The sample size of 130 patients was calculated as follow: Based on the assumption that cumulative recovery rate will increase to 20% using the end-to-side anastomosis, it was calculated that 65 patients should be in each group. The sample size was calculated by the formula for a power 80%, alpha error of 0.05 and dropout rate of 10%.