GASTROINTESTINAL TRANSIT AND PROLONGED AMBULATORY COLONIC MOTILITY INHEALTH AND FECAL INCONTINENCE

Background-Colonic motor function has not been studied in the ambulato ry setting over a prolonged period in the unprepared state. Furthermor e, the disturbance of this function in patients with faecal incontinen ce is unknown. Aim-To study colonic function over two to three days in the ambulatory unprepared state in health and in patients with idiopa thic faecal incontinence. Methods-Six healthy women and six women with faecal incontinence and a structurally intact anal sphincter ingested a dual radioisotope meal, and had a six sensor, solid state manometri c probe colonoscopically inserted into the left colon. Scanning was pe rformed until radioisotope left the gut and pressure was recorded for a median of 44 hours. Results-Three of six patients showed abnormal ga stric emptying. Patients showed no disturbance of colonic radioisotope transit. Controls had a median of 12, whereas patients had a median o f 16, high amplitude propagated waves per 24 hours. In three patients urge incontinence was associated with high amplitude (up to 500 cm wat er) propagated waves which often reached the rectum. These high pressu re waves were identical to those occuring in healthy subjects, the onl y difference being the]lack; of adequate sphincter response. Passive i ncontinence was not associated with colonic motor activity. Defaecatio n in all subjects was associated with identical propagated waves, and distal movement of 13% (median) of right colonic content and excretion of 32% from the left colon and rectum. The urge to defaecate was asso ciated with either propagated waves (45%) or non-propagated contractio ns (55%). Rectal motor complexes were recorded in both groups of subje cts, but similar rhythmic activity was also recorded in the sigmoid an d descending colon. Conclusions-Normal colonic function consists of fr equent high pressure propagated waves. Rhythmic activity occurs both p roximal to and in the rectum. Defaecation is characterised by high pre ssure propagated waves associated with coordinated anal sphincter rela xation. Patients with faecal incontinence may have a widespread distur bance of gut function. Urge incontinence, an urge to defaecate, and de faecation can all be associated with identical high amplitude propagat ed pressure waves.