Background: Addition of a colonic pouch to an ultralow anterior resection or a coloanal anastomosis can improve the functional outcome, but may also cause evacuation difficulties. This study was conducted to evaluate the selective use of colonic pouches, based upon the diameter of the proximal colon.
Methods: Twenty-nine rectal cancer patients underwent ultralow anterior resection or coloanal anastomosis, between July 1998 and January 2000. Seventeen had a stapled straight anastomosis, while 12 had a stapled colonic pouch-anal anastomosis. The method of reconstruction was selected intraoperatively based on the diameter of the proximal colon as measured by metal sizers. The colonic J-pouch was constructed with 6-cm limbs using GIA60. Median follow-up was 9 months (range 6- 23 months). Data about complications, tumour characteristics and height of anastomoses were collected. Postoperative bowel function was assessed at 3 and 6 months after surgery or closure of ileostomy using a standard bowel function questionnaire.
Results: The 2 groups were comparable regarding age, sex, Dukes stage, resection margins and height of the anastomosis. All anastomoses were 2 - 5.5 cm from the anal verge. The operations were covered by a loop ileostomy in 2 of the straight anastomoses and 4 of the pouches. Two patients had intraoperative complications; splenic injury needing splenectomy and bleeding from pelvic side walls requiring packing. One patient died from multiorgan failure on the 6th postoperative day and was excluded from functional analysis. Four patients had postoperative complications including 2 adhesive bowel obstructions, major wound infection and a subphrenic collection. There were no clinical leaks or pouch-vaginal fistulae. Colonic pouches proved to result in superior functional result in the first 6 months postoperatively compared with straight anastomoses. Pouch patients had less frequency, urgency and need for constipating drugs. None of the pouch patients had evacuation difficulties. Adaptation of straight anastomosis patients resulted in comparable bowel function after 6 months in most patients.
Conclusions: Patients with narrow proximal colon, not accepting 31 mm sizer need a colonic pouch added to ultralow or coloanal anstomosis to achieve good postoperative bowel function. Other patients with capacious proximal colon can be expected to achieve equally good functional results after 6 months without the need for a colonic pouch