Prospective randomized controlled study of clinical function and anorectal physiology after low anterior resection: Comparison of straight and colonic J pouch anastomoses

Abstract

Clinical function and anorectal physiology were studied prospectively in patients with rectal cancer after low anterior resection, randomized to either a straight anastomosis or an 8‐cm colonic J pouch anastomosis. Sixteen patients (mean(s.e.m.) age 61·2(3·2) years; ten men, six women) had a straight anastomosis and 17 (mean(s.e.m.) age 61·2(3·8) years; six men, 11 women) a colonic pouch anastomosis. At 1 year after low anterior resection, a bowel function questionnaire was administered and anorectal physiology tests were performed. Patients with a straight anastomosis had significantly more frequent stools (median 6 (range 3–7) daily) compared with those who had a pouch (median 3 (range 2–7) daily; P = 0·02). A frequent sensation of incomplete defaecation was found in three patients with a straight anastomosis compared with ten who had a pouch anastomosis (P = 0·02). The mean resting anal pressures were lower after colonic pouch anastomosis (P = 0·049) but there were no differences in anal squeeze pressure, rectal sensation, volume of first sensation and compliance between the two groups. The decreased stool frequency with an 8‐cm colonic pouch was not associated with measured improvements in rectal reservoir function. It is possible that reversed propulsive activity may be important in smaller colonic J pouches.