Physiologic assessment of the four commonly performed endorectal pullthroughs.

The popularity of the endorectal pullthrough for the treatment of benign mucosal diseases of the rectum has created a controversy regarding the need for a reservoir. The four currently advocated procedures, the straight endorectal anastomosis, the J pouch, the S pouch, and the lateral isoperistaltic ileal reservoir were evaluated in a puppy model with four animals in each experimental group. Measurement of rectal capacitance showed that all groups achieved 80-85% of control values at 6 months after surgery. Intestinal transit time decreased by one-half in all groups. Stool consistency, stool culture, water, and electrolyte absorption did not show any statistical superiority of one group over another. Stool frequency varied widely at 6 months; 10 stools per 8-hour period were counted in the lateral reservoir group versus 25 with the J pouches, and 16 with the straight and S groups. Stool frequency did not correlate with transit time, stool consistency, or rectal capacitance. Barium enemas showed that straight pullthroughs more closely resembled the measurements of the normal animal's endorectal canal. Based on these studies, there appears to be no advantage to adding a reservoir to the endorectal pullthrough.