Meta-analysis of colonic reservoirs versus straight coloanal anastomosis after anterior resection

Background and methods: The comparative benefits and drawbacks of straight coloanal anastomosis (CAA), colonic J-pouch and coloplasty anastomosis after anterior resection are uncertain. Studies published between 1986 and 2005 of colonic J-pouch versus transverse coloplasty or straight CAA were analysed. Endpoints included postoperative complications, and functional and physiological outcomes measured within 6 months, 1 year and 2 years or more after the procedure. A random-effect model was used to aggregate the study endpoints and assess heterogeneity. Results: Thirty-five studies containing 2240 patients (1066 straight CAA, 1050 J-pouch and 124 coloplasty) were included. There was no significant difference in postoperative complications between the three groups. There was a significant reduction in the frequency of defaecation per day by 1.88, 1.35 and 0.74 motions at the three time intervals in the J-pouch group compared with the straight CAA group. Faecal urgency was less prevalent in patients with a J-pouch than those with a straight CAA (odds ratio 0.27 at 6 months or less and 0.21 at 1 year). There was no difference in functional outcome between J-pouch and coloplasty anastomosis. Conclusions: The colonic J-pouch provided functional benefits over straight anastomosis with no increase in postoperative complications. Coloplasty appeared to have similar benefits but further studies are required for validation.