Recovery of physiologic and clinical function after low anterior resection of the rectum for carcinoma

Abstract

The aim of this study was to examine the serial changes that take place in the first year after low anterior resection for rectal carcinoma, in terms both of anorectal physiology and clinical bowel function. Our hypothesis was that some patients never regain satisfactory anorectal function, because the operative procedure leads to permanent impairment of anorectal reflex and motor function. Nineteen patients underwent serial tests of anorectal function, before and for one year after low anterior resection. The median level of the anastomosis above the anal high-pressure zone was 3 (range, 1-6) cm. Anal resting pressure (median (interquartile range)) was significantly decreased three months after operation (62 (46-72) cm H2O) and one year after operation was still significantly less (58 (48-73) cm H2O) than before operation (77 (58-93) cm H2O)(PCONCLUSIONS: Anal resting pressure decreased significantly after low anterior resection and did not recover in the course of the first year after operation. Moreover, the volume of an air-filled balloon in the neorectum that was required to elicit maximum inhibition of the anal sphincter was significantly less after anterior resection than before operation. These long-term and presumably permanent changes in physiologic behavior of the anoneorectum after low anterior resection provide an explanation for the failure of some patients to regain satisfactory bowel function following that procedure.