Efficacy of Sacral Nerve Stimulation Before Definitive Implantation (SNStest)
Sacral nerve stimulation (SNS) is an emerging treatment for patients with severe fecal incontinence. The test stimulation is minimally invasive, associated to low morbidity and relatively cheap. On the contrary, implantation of the definite stimulator is related to higher morbidity and considerable costs. A careful patent selection for definite implantation is therefore crucial. However, indication for implantation is actually based only on the subjective criteria reported in the patients´ diary only. Patients and care providers are likely to overestimate the real effect of SNS leading to an unjustified overuse of this expensive device. It is therefore necessary to evaluate real efficacy of SNS during the testing phase in a unbiased setting in order to avoid unnecessary morbidity and costs.
|Study Design:||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||Efficacy of Sacral Nerve Stimulation Before Definitive Implantation: a Multicenter Randomized, Double Blind, Crossover Trial|
- Primary success rate of SNS after 7 days. By convention this is assessed by >50% reduction in the number of episodes in the symptom diary. [ Time Frame: 24 months ]
|Study Start Date:||September 2007|
|Estimated Study Completion Date:||December 2009|
|Estimated Primary Completion Date:||December 2009 (Final data collection date for primary outcome measure)|
Phase 1: sacral nerve stimulation crossover Phase 2 : sham stimulation
|Procedure: sacral nerve stimulation|
Phase 1: sham stimulation crossover Phase 2: sacral nerve stimulation
|Procedure: sacral nerve stimulation|
Sacral nerve stimulation (SNS) is an emerging treatment for patients with severe faecal incontinence when conservative measures fail and surgical repair is not indicated. In a minimally-invasive approach and under local anaesthesia, an electrode is placed around sacral nerve root S2-4 and electrical stimulation is applied to the sacral spinal nerves. Effectiveness of SNS is definitively not only explained by placebo effect but the pathophysiologic mechanisms remain unclear. Suggested pathways include modulation of afferent nerve fibres and direct stimulation of the pelvic floor and anal sphincter muscle. After placement of the electrode, the patient is stimulated by an external stimulator for 1-3 weeks. During this period, the patient documents the number of faecal incontinence episodes or urgencies in a symptom diary. By convention, indication for permanent stimulation is based on a 50% reduction in the number of episodes. After a successful testing period, the permanent stimulator is implanted, generally in the upper gluteal region.
Previous studies report success rates up to 80%. The only randomized trial with a proper sample size evaluated the efficacy of SNS after definite implantation. In this study, 63% of the patients felt improved during the placebo period and might not really benefit from the device. The real success rate of SNS is therefore likely to be considerably lower. Efficacy of SNS during the testing phase has never been assessed in a blinded randomized study.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00522691
|Visceral surgery, university hospital|
|Lausanne, Vaud, Switzerland, 1005|
|Principal Investigator:||Martin Hubner, MD||Visceral Surgery, University Lausanne, Switzerland|
|Study Director:||Jean-Claude Givel, Professor||Visceral Surgery, University Lausanne, Switzerland|
|Study Chair:||Nicolas Demartines, Professor||Visceral Surgery, University Lausanne, Switzerland|