Long-term results of subtotal colectomy for severe slow-transit constipation in patients with normal rectal function

The outcome of subtotal colectomy for severe constipation may be difficult to predict. One factor, which probably is of major importance for the functional outcome, is rectal function. The aim of the study has been to evaluate long-term results after subtotal colectomy with ileo-rectal anastomosis in a group of patients with severe slow-transit constipation but without evidence of impaired rectal emptying.

Of 273 patients with constipation referred for surgical evaluation 18 (7%) fulfilled our criteria for subtotal colectomy. Slow-transit was confirmed by radio-opaque marker studies and normal rectal function by emptying of viscous fluid and normal emptying at defecography.

At follow up between 3 and 9 years 15 patients had a bowel frequency between 2 and 6 daily. One patient, who had an ileostomy because of anastomotic leak, had not wanted bowel continuity restored. One patient with opiate abuse became less constipated with 2-3 bowel movements a week. One patient was still constipated one year after the operation and subsequently had an ileal pouch-anal anastomosis. This patient who had normal rectal emptying had a very high volume tolerability with a maximum tolerable volume of 700 ml. In 4 of 7 patients abdominal pain persisted after the operation, and 3 developed diarrhoea, which required daily intake of loperamide.

Subtotal colectomy for severe slow-transit constipation is justified provided anorectal function is normal. In spite of normal rectal emptying very high rectal volume tolerability may be an indicator of functional megarectum and impaired rectal emptying postoperatively.