Effect of electrical stimulation in constipated patients with impaired rectal sensation.

Abstract

A subgroup of constipated patients complain of absent or diminished sense of wanting to defecate, suggesting that one of the causes of constipation is impaired rectal sensation. Electrical stimulation therapy (EST) has recently been used to treat patients with urinary and/or fecal incontinence. This study evaluated the efficacy of EST in constipated patients, especially those with impaired rectal sensation. Of the 130 patients with functional constipation as defined by Rome II criteria, 22 patients who had impaired rectal sensation (rectal desire threshold volume > or =90 ml) on an anorectal manometry were selected. We treated 12 with EST and 10 with biofeedback therapy (BFT) according to a randomized order. Overall symptoms of patients significantly improved after each therapy in both groups. Interestingly, frequency of sense of wanting to defecate improved only after EST. On objective findings there was significant improvement in anal residual pressures on attempted defecation only after BFT solely. On the other hand, rectal sensory threshold volumes for desire and urge to defecate and maximal tolerated volume improved significantly only in the EST group. Our findings show that the efficacy of EST can be comparable to BFT in a subgroup of constipated patients, especially those with impaired rectal sensation. EST might be considered as an adjunctive therapeutic modality for the management of functional constipation with impaired rectal sensation.