Operative time and surgical efficiency in end-to-end versus side-to-end colorectal anastomosis for rectal cancer

Background: Side-to-end anastomosis (SEA) and end-to-end anastomosis (EEA) are widely used techniques in colorectal cancer surgery, yet their comparative outcomes remain a subject of debate. This study evaluates operative time, surgical efficiency, and functional outcomes of SEA versus EEA in patients undergoing low anterior resection for rectal cancer. Methods: A prospective observational study was conducted at Bangabandhu Sheikh Mujib Medical University, (BSMMU) Dhaka, from March to November 2023. Forty-four patients were purposively sampled and randomized into SEA and EEA groups. Intraoperative variables, postoperative outcomes, and functional results, including low anterior resection syndrome (LARS) scores, were evaluated at multiple intervals. Data were analyzed using SPSS version 25, with p<0.05 considered significant. Results: The ASA PS classification and preoperative tumor stages were similar across groups. Splenic flexure mobilization was universally performed in SEA (100%) and in 90.9% of EEA patients (p=0.385). Blood loss was comparable between groups (<100 mL in 90.9% of SEA and 95.5% of EEA, p=0.157). Operative time was significantly longer in SEA (183.0±10.2 minutes) compared to EEA (151.0±12.8 minutes, p<0.05). Postoperative LARS scores revealed no significant differences, with major LARS observed in 39% of EEA patients and 61% of SEA patients (p>0.05). Anastomotic line bleeding was infrequent in both groups, with no statistically significant differences. Conclusions: Both SEA and EEA demonstrated comparable safety and functional outcomes in rectal cancer surgery. SEA was associated with longer operative times but offered similar functional and surgical efficiency. The findings highlight the viability of both techniques, with the choice depending on patient-specific and surgical considerations.