Rectal Prolapse - Clinical Assessment

Ian Adams, Sheffield Teaching Hospitals NHS Trust

Powerpoint File

Many surgeons contend that patients with rectal prolapse should go straight to surgery without any need for further investigations, apart from a rigid sigmoidoscopy to exclude a rectal polyp or cancer. Some however have consistently argued that this should not be the case. They assert that the variable results of prolapse repair reported in the literature "behoves us to select a procedure which will best correct the functional disturbances as well as the prolapse". This opinion leads to a question - how should such patients be clinically assessed? Most authors suggest that the investigations requested should be dictated by 3 clinical criteria - the presence or absence of constipation, diarrhoea or incontinence - along with what is found at a careful digital examination.

Constipation. The importance of establishing a history of constipation is well accepted, as many surgeons would advocate sigmoid resection at the time of rectopexy in constipated patients. However, it is important to exclude those patients who might have slow transit, which might benefit from subtotal colectomy with rectopexy instead. Where doubt as to the aetiology of constipation occurs, colonic transit studies are recommended.

Diarrhoea. A subgroup of rectal prolapse patients have diarrhoea, often with associated incontinence. Bowel investigations should be considered in the diarrhoea subgroup, especially in younger patients. Our policy in Sheffield is to perform at least flexible sigmoidoscopy in all rectal prolapse patients with diarrhoea, although data to support this is sparse.

Incontinence. Resting and squeeze anal pressures are reduced in rectal prolapse patients with incontinence, with evidence suggesting both internal and external sphincter dysfunction. This dysfunction will improve in a proportion of patients following surgery. There is some evidence that anorectal manometry might predict which patients remain incontinent after surgery, suggesting some value in measurement in those patients for whom continuing incontinence is a particular concern.

Examination. Although some patients can readily demonstrate a prolapse in the left lateral position, this is not the usual state of affairs. A patient may give a good history of prolapse but be too embarrassed demonstrate it. More of a problem is the patient with a history of mucus discharge and bleeding in the presence of incontinence/disordered defaecation who is unaware of a prolapse. A full examination for prolapse should include asking the patient to squat down and strain. If unsuccessful, then the patient should be examined whilst straining on a toilet/commode should. If clinical suspicion continues despite negative examination, defaecating proctogram will often reveal the problem.

Differential diagnosis during examination from prolapsing piles can be a problem. Along with differentiation by careful digital examination, straining during proctoscopy should also help distinguish the difficult case. Another possible cause for confusion is the case of a defect in the external anal sphincter resulting in a prolapsing area of mucosa overlying the injury. Digital examination will easily feel the gutter deformity. Documentation of obstetric history is appropriate in all cases of rectal prolapse.

Conclusion. A careful history and examination along the lines above remains the cornerstone of successful operative management in rectal prolapse, and indeed for the appropriate counselling of patients for the entry into the PROSPER trial.