Colectomy for slow-transit constipation: preoperative functional evaluation is important but not a guarantee for a successful outcome.

Purpose: This study was designed to assess the results of preoperative functional evaluation of patients with severe slow-transit constipation in relation to functional outcome.

Methods: Four hundred thirty-nine patients with chronic intractable constipation were evaluated by marker studies. Twenty-one patients underwent colectomy and ileorectal anastomosis for slow-transit constipation. Mean colorectal transit time was 156 hours (normal, <45 hours). Small-bowel transit time was normal in ten patients and delayed in five patients. Six were nonresponders. Morbidity was 33 percent. Small-bowel obstruction occurred in six patients; relaparotomy was done in four patients. Follow-up varied from 14 to 153 (mean, 62) months.

Results: After three months, defecation frequency was increased in all. Mean stool frequency improved from one bowel movement per 5.9 days to 2.8 times per day. Sixteen patients felt improved after surgery. Seventeen continued to experience abdominal pain, and 13 still used laxatives and enemas. Satisfaction rate was 76 percent (16 patients). After one year, defecation frequency was back at the preoperative level in five patients. An ileostomy was created in two more patients because of incontinence and persistent diarrhea. Eleven patients (52 percent) still felt improved. A relation between small-bowel function and functional results could not be demonstrated.

Conclusions: Preoperative evaluation is important but not a guarantee for, successful outcome. Colectomy remains an ultimate option for patients with disabling slow-transit constipation, but patients should be informed that, despite an increased defecation frequency, abdominal symptoms might persist. Any promiscuous use of colectomy to treat constipation should be discouraged.