Evaluation of ileal W pouch-anal anastomosis for restorative proctocolectomy

Clinical defaecatory function, neorectoanal manometry and pouchography were assessed in 16 patients treated by restorative proctocolectomy with ileal W-reservoir. The duration after ileostomy closure was 6 to 28 months (mean 17 months). There were no operative deaths and no failures where the reservoir had to be removed. Partial anastomotic dehiscence occurred in one patient, and intestinal obstruction requiring laparotomy in two. Anastomotic stricture, which could be corrected easily by dilatation, occurred in three patients. Daily stool frequency was 4.3 +/- 1.2 at 6 months after ileostomy closure, 3.8 +/- 1.2 at 12 months, and 3.3 +/- 1.0 at 24 months. The clinical score for neorectal function gradually and steadily improved with time as well as daily stool frequency. In the manometric and pouchographic studies, mean anal canal length (3.4 +2- 0.6 cm), mean maximal anal sphincter resting pressure (57.1 +/- 9.7 cm water) and mean maximal reservoir resting pressure (4.3 +/- 2.0 cm water) tended to be less than normal controls but not significantly so. Neorectoanal inhibitory reflex disappeared completely or was greatly decreased in all patients. However, all were capable of spontaneously controlled defaecation. There was an inverse linear relationship between daily stool frequency and maximal tolerated reservoir volume (p less than 0.01). There were inverse linear relationships also between daily stool frequency and horizontal diameter of the reservoir measured on pouchography (p less than 0.05), and daily stool frequency and dilatation ratio of the reservoir (p less than 0.01). From these results, we conclude that a large and wide reservoir allows better defaecatory function.