Objective: Constipation is a major problem for patients with chronic spinal cord injury (SCI). However, it is not clear whether abnormal colonic transit is restricted to the rectosigmoid region or involves the entire colon. We assessed regional colonic transit with emphasis on the ascending and transverse segments in patients with chronic SCI and compared the results with those of controls using scintigraphic techniques.
Methods: Seven patients with SCI below T1 and 10 control subjects were studied after oral ingestion of a capsule containing indium-111-labeled Amberlite (Sigma Chemical, St. Louis, MO) pellets. The capsule was coated with a pH-sensitive polymer that prevents disintegration until it reaches the ileocecal region. Assessments of the half-time of emptying and residence time of contents in ascending and transverse segments were made, as well as an assessment of the velocity of contents throughout the entire colon, including the descending colon.
Results: A significantly slower half-time of emptying was found in SCI patients (ascending: 29 +/- 27 hr in SCI, 6.81 +/- 3.03 hr in controls, p < 0.01; ascending + transverse: 42 +/- 12 hr in SCI, 15.3 +/- 7.16 hr in controls, p < 0.01). The residence time of the median position of the contents was significantly prolonged in SCI patients (ascending: 31 +/- 23 hr in SCI, 8.75 +/- 4.68 hr in controls, p < 0.05; transverse: 26 +/- 3 hr in SCI, 5.0 +/- 4.4 hr in controls, p < 0.05). Overall, the velocity of the median position of contents throughout the entire colon was significantly lower in SCI (0.63 +/- 0.33 cm/hr in SCI, 2.58 +/- 1.20 cm/hr in controls, p < 0.001).
Conclusions: Patients with chronic SCI have prolonged colonic transit that involves the entire colon. Hence, treatment of constipation in these patients may need to include prokinetic agents as well as local rectal maneuvers.