Bowel Dysfunction and Colon Transit Time in Brain-Injured Patients

OBJECTIVE: To report the defecation patterns of brain-injured patients and evaluate the relationship between functional ability and colon transit time (CTT) in stroke patients. METHOD: A total of 55 brain-injured patients were recruited. Patient interviews and medical records review of pattern of brain injury, anatomical site of lesion, bowel habits, constipation score, and Bristol scale were conducted. We divided the patients into constipation (n=29) and non-constipation (n=26) groups according to Rome II criteria for constipation. The CTTs of total and segmental colon were assessed using radio-opaque markers Kolomark(R) and functional ability was evaluated using the functional independence measure (FIM). RESULTS: Constipation scores in constipation and non-constipation groups were 7.32+/-3.63 and 5.04+/-2.46, respectively, and the difference was statistically significant. The CTTs of the total colon in both groups were 46.6+/-18.7 and 32.3+/-23.5 h, respectively. The CTTs of total, right, and left colon were significantly delayed in the constipation group (p<0.05). No significant correlation was found between anatomical location of brain injury and constipation score or total CTT. Only the CTT of the left colon was delayed in the patient group with pontine lesions (p<0.05). CONCLUSION: The constipation group had significantly elevated constipation scores and lower Bristol stool form scale, with prolonged CTTs of total, right, and left colon. In classification by site of brain injury, we did not find significantly different constipation scores, Bristol stool form scale, or CTTs between the groups with pontine and suprapontine injury.

Change of Tetrodotoxin Sensitive Inhibitory Neural System of the Colon in Spinal Cord Injured Rats

OBJECTIVE: To investigate the effect of spinal cord injury (SCI) on contractions of whole colonic preparation isolated from rats under the inhibition of nitrergic inhibitory neural system using tetrodotoxin (TTX). METHOD: Twenty Sprague-Dawley rats were used. A complete spinal cord transection was performed surgically at the T10 cord level in spinal cord injured group. After 1 week of operation, sensory and motor functions were assessed and colon was removed under anesthesia for in vitro motility study. Whole colon was divided into four segments: proximal, two mid colon and distal colon. Each segment of colon was mounted with longitudinal direction in a 10 ml organ bath. After 1 hour of equilibration, frequency, area under the curve of spontaneous contraction and the response to acetylcholine (Ach), KCl and TTX were measured in each segment. Also the responses to Ach and KCl response under TTX pretreatment were measured. RESULTS: Enhanced contractile response to KCl solution (40 mM), TTX (1 micrometer) and Ach (10(-6) M) was observed in both group. There was no statistical difference in spontaneous, Ach and KCl induced contraction between control and SCI rats, but TTX induced contraction was decreased in SCI group than control group (p<0.05). In addtion, the Ach and KCl responses under the TTX pretreatment were significantly decreased in SCI group than control group (p<0.05). CONCLUSION: These results suggest that the change of colonic contractility after the SCI is caused by at least partly from the change of TTX related inhibitory neural system.