Single lumen ileum with myectomy: A possible alternative to the pelvic reservoir in restorative proctocolectomy

An alternative procedure to construction of a pelvic ileal reservoir was assessed which avoids the need for a pouch, while providing an adequate rectal substitute and good continence. Thirty‐six female adult beagles were allotted randomly to undergo total colectomy with (a) ileo—anal anastomosis alone, (b) ileo‐anal anastomosis with two 15 cm myectomies, (c) ileo‐anal anastomosis and myectomy with an ileo‐ileal valve, or (d) ileo‐anal anastomosis with a duplicated J pouch. The animals were studied before operation and at 4‐weekly intervals for 20 weeks after operation. Mortality rates were similar. Ileal compliance was increased significantly by myectomy from 0·64 ml/mm Hg (median, interquartile range 0·49–0·78) after ileo‐anal anastomosis alone to 1·65 mmHg (1·16–1·93), P < 0·01, an increase which was maintained. Heal capacity was also increased both by myectomy and by the J pouch: ileo‐anal anastomosis = 85 ml (75–100 ml), ileo‐anal anastomosis and myectomy = 139 ml (116–156 ml), ileo‐anal anastomosis and myectomy and ileo‐ileal valve = 125 ml (range 85–145 ml), ileo—anal anastomosis and J pouch = 130 ml (range 75–165 ml) (P < 0·01). Bowel function in the other three groups was markedly superior to ileo—anal anastomosis alone. Mean transit time was significantly less after ileo—anal anastomosis, 5·2 h (2·6–8·2 h) than after both ileo—anal anastomosis and myectomy, 10·5 h (9·6–13·9 h), P < 0·05 and ileo‐anal anastomosis and J pouch, 11·0 h (8·4–13·0 h), P < 0·05, but addition of an ileo‐ileal valve did not produce a further increase in transit time, 12·9 h (range 10·5–14·5 h), P = n.s‥ Myectomy of single lumen ileum may be a useful alternative to a pelvic Heal reservoir in restorative proctocolectomy.