PHYSIOLOGICAL-CHARACTERISTICS OF STRAIGHT AND COLONIC J-POUCH ANASTOMOSES AFTER RECTAL EXCISION FOR CANCER

PURPOSE: The colonic J-pouch anastomosis has been advocated to obviate urgent and frequent defecations following a sphincter-saving rectal e xcision. Physiologic characteristics of the colonic J-pouch were compa red with those of the traditional straight anastomosis and related to clinical function. METHOD: Patients with total mesorectal excision for carcinoma were randomized to either a straight (n = 23) or a colonic pouch anastomosis (n = 23). The patients were examined before and at o ne year after surgery (n = 42), which included laboratory studies, and a questionnaire regarding anorectal function was completed. RESULTS: Preoperative compliance of the rectum was restored after surgery in th e pouch group, 2.9 (2.2-3.4) ml/cm H2O but there n as a significant de crease after surgery in the straight anastomosis group, 2.9 (1.1-2.3) P < 0.001 (median (interquartile range)). Sphincter pressures in both groups were similar. In a multiple regression analysis, high complianc e mas associated with favorable clinical function. and hypermotility o f the anal canal was associated with adverse clinical function. CONCLU SIONS: Colonic pouch-anal anastomosis restores neorectal compliance, w hich is important for good function after low anterior resection. Pres ence of an unstable internal sphincter is a negative factor for clinic al function in both straight and pouch anastomoses.