A physiological comparison between idiopathic and post-hysterectomy constipation

Abstract

SUMMARY
In order to gain more insight into the pathophysiology of
severe constipation, anorectal manometry, sphincter electromyography,
whole gut tansit time and a test of defaecation
of a simulated stool were carried out in 22 female patients
with severe idiopathic constipation, 14 patients with
severe constipation after hysterectomy and 20 female normal
controls. Only 1/23 patient with idiopathic constipation
compared with 6/14 patients with post hysterectomy
constipation showed normal transit time (p<0.01). In those
with abnormal transit, the markers were in the distal colon
in patients with post hysterectomy constipation but were
likely to be spread along the colon in patients with idiopathic
constipation. Seven patients with post hysterectomy
constipation showed abnormal anal pressure oscillations
[amplitude: 10-50cmH2O (median=25cmH2O); frequency:
4-10min-1 (median=8min-1)] during basal recordings, compared
with only 1 patient with idiopathic constipation
(p<0.01). There were no significant differences in basal and
squeeze anal pressures between any of the groups, but similar
percentages of patients in each constipated group
showed paradoxical increases in the electrical activity of
the EAS when they strained to pass a simulated stool. The
lowest rectal volumes required to induce initial and sustained
anal relaxation and to elicit sensations of desire to defaecate and discomfort were significantly higher (p<0.05)
in both groups of patients with constipation compared with
normal controls. In conclusion, though the two groups of
constipation share some similarities, the defect is more localized
in the anorectum in patients with post hysterectomy
constipation.
Key words: Post-hysterectomy, idiopathic, constipation
inhibition in 50%