The National Institute for Clinical Excellence is examining artificial anal sphincter implantation and will publish guidance on its safety and efficacy to the NHS in England, Wales and Scotland. The Institute's Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisors, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about artificial anal sphincter implantation.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

• comments on the preliminary recommendation
• the identification of factual inaccuracies
• additional relevant evidence.

Note that this document is not the Institute's formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that the Institute will follow after the consultation period ends is as follows:

• The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
• The Advisory Committee will then prepare draft guidance, which will be the basis for the Institute's guidance on the use of the procedure in the NHS in England, Wales and Scotland.

For further details, see the Interim Guide to the Interventional Procedures Programme, which is available from the Institute's website (www.nice.org.uk/ip).

Closing date for comments: 24 February 2004

Target date for publication of guidance: May 2004

Note that this document is not the Institute's guidance on this procedure. The recommendations are provisional and may change after consultation.

Current evidence on the safety and efficacy of artificial anal sphincter implantation does not appear adequate for this procedure to be used without special arrangements for consent and for audit or research.

Clinicians wishing to undertake artificial anal sphincter implantation should take the following action.

• Inform the clinical governance leads in their Trusts.
• Ensure that patients understand the uncertainty about the procedure's safety and efficacy and provide them with clear written information. Use of the Institute's Information for the Public is recommended.
• Audit and review clinical outcomes of all patients having artificial anal sphincter implantation. Publication of safety and efficacy outcomes will be useful in reducing the current uncertainty. The Institute may review the procedure upon publication of further evidence.

It is recommended that this procedure be carried out only in units with a specialist interest in faecal incontinence.

The causes of faecal incontinence are diverse. Existing treatment options include medical therapy, biofeedback techniques and surgery in selected patients. Surgical treatments include sphincter repair, sacral nerve stimulation, encirclement procedures and muscle transposition (for example, dynamic graciloplasty). Some patients may require a colostomy if other treatments fail.

Implantation of an artificial anal sphincter is used to treat severe faecal incontinence. In this procedure, a fluid-filled cuff is implanted around the anal canal. Tubing from the cuff is channelled under the skin of the perineum and connected to a control pump placed subcutaneously in the scrotum or labia. The control pump is connected by tubing to a pressure-regulating balloon implanted in the abdominal wall. The cuff simulates the natural function of the sphincter muscle; when the fluid is displaced from the cuff to the balloon via the patient-controlled pump, defaecation can take place. Once defaecation is complete, the fluid is slowly returned to the cuff and continence is again achieved. For more details, refer to the sources of evidence (see Appendix).

No controlled studies were identified. Some of the studies identified were small and some had high losses to follow-up. Among the studies identified, removal of the artificial sphincter system was required for 19% (10/53) to 41% (7/17) of patients. For patients who had not undergone explantation, all the studies showed improvement in continence. However, different measures of continence were used among the studies. The studies that reported manometric results showed increased mean anal pressures after implantation. For more details, refer to the sources of evidence (see Appendix).

The Specialist Advisors considered the main efficacy concern to be the frequent need to remove the implanted artificial sphincters.

The largest study identified reported that device-related complications occurred in 86% (99/115) of patients. The most common adverse events reported in this study were: infection 33% (38/115); pain 32% (37/115); erosion 21% (24/115); faecal impaction 18% (21/115); faecal incontinence 18% (21/115); constipation 17% (20/115); surgical injury 13% (15/115); wound problems 10% (11/115); difficult evacuation 9% (10/115); and wound dehiscence 9% (10/115). For more details, refer to the sources of evidence (see Appendix).

The Specialist Advisors considered the main safety concerns to be infection, erosion and evacuation difficulties.

The procedure may have a place in the treatment of patients who are unsuitable for sacral nerve stimulation.

There is a significant rate of complications such as infection, cuff erosion, wound dehiscence and haematoma, and patients may require revisional surgery or removal of the device. Fully informed consent is therefore particularly important.

The following document, which summarises the evidence, was considered by the Interventional Procedures Advisory Committee when making its provisional recommendations.

• Interventional Procedure Overview of artificial anal sphincter implantation, November 2002

Available from: www.nice.org.uk/ip128overview