The National Institute for Clinical Excellence is examining vagus nerve stimulation for refractory epilepsy in children and will publish guidance on its safety and efficacy to the NHS in England and Wales. 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 vagus nerve stimulation for refractory epilepsy in children.

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

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 the Final Interventional Procedure Document (FIPD) and submit it to the Institute.
• The FIPD may be used as the basis for the Institute's guidance on the use of the procedure in the NHS in England and Wales.

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: 23 December 2003

Target date for publication of guidance: March 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 vagus nerve stimulation for refractory epilepsy in children appears adequate to support the use of the procedure, provided that the normal arrangements are in place for consent, audit and clinical governance.

The procedure should only be used to treat children whose epilepsy has failed to respond adequately to medical treatment.

The procedure should only be undertaken by specialist paediatric epilepsy teams.

Current evidence on the efficacy of the procedure appears adequate as a means of reducing seizure frequency. However the effect on quality of life remains uncertain. Future audit and research should include quality of life measures. Patients, carers and children should be informed about the unpredictability of benefit. Use of the Institute's Information for the Public is recommended.

Vagus nerve stimulation is indicated for use as an adjunctive therapy in reducing the frequency of seizures in patients whose epileptic disorder is dominated by partial seizures (with or without secondary generalisation) or generalised seizures, which are refractory to anti-epileptic medications.

A battery-powered pulse-generating device is implanted under the skin of the upper left chest. A wire is tunnelled under the skin and connected to the left vagus nerve in the neck. The stimulation parameters (pulse width and frequency, current intensity, on/off cycles) are programmed into the pulse generator via a programming wand. Patients or carers can give additional stimulation or temporarily inhibit stimulation. The battery lasts 8-10 years and can be replaced under local anaesthesia. A typical treatment regimen might comprise intermittent stimulation for 30 seconds every 5 minutes throughout the day and night.

In one study of 50 children aged 12 years and younger, 23 (46%) experienced a greater than 50% reduction in seizure frequency. In a smaller study of 28 children aged 12 years and younger, a mean reduction of 62% in seizure frequency was reported at one year. There was some evidence to suggest that quality of life improved following the procedure. Comparisons are difficult to make among the studies because of variations in the patient populations, the reporting of outcomes and the methods of outcome assessment. For more details, refer to the sources of evidence (see Appendix).

The Specialist Advisors considered that about 50% of patients having vagus nerve stimulation experienced approximately a 50% reduction in seizure frequency. One Specialist Advisor stated that this figure was documented for adults, and although the outcomes seemed similar in children, not enough data had been published. Two Advisors also noted that the procedure seemed to have some benefits in terms of mood and quality of life.

The most commonly reported complications were hoarseness, sore throat and cough. In a case series of 125 children, 58% and 38% of children experienced voice alteration and coughing, respectively, during stimulation. More serious adverse events included infection (requiring device removal) and breathing irregularities, but these only occurred in a small number of patients. For more details, refer to the sources of evidence (see Appendix).

The Specialist Advisors believed that this is a safe procedure with no major complications.

NICE is in the progress of developing a clinical guideline on epilepsy. The expected date of issue is June 2004.

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

• Interventional Procedure Overview of Vagus nerve stimulation for refractory epilepsy in children, June 2003

Available from: www.nice.org.uk/ip122boverview