Assessing motility of the gastrointestinal tract using a wireless capsule: consultation
Interventional procedure consultation document
Assessing motility of the gastrointestinal tract using a wireless capsule
In this procedure, a capsule with a tiny wireless transmitter is swallowed, and transmits information about the movements and contents of the gut to an external device. The capsule moves through the gut and is passed out of the bowel with the faeces.
The National Institute for Health and Care Excellence (NICE) is examining assessing motility of the gastrointestinal tract using a wireless capsule and will publish guidance on its safety and efficacy to the NHS. NICE’s Interventional Procedures Advisory Committee has considered the available evidence and the views of specialist advisers, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about assessing motility of the gastrointestinal tract using a wireless capsule.
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 provisional recommendations
- the identification of factual inaccuracies
- additional relevant evidence, with bibliographic references where possible.
Note that this document is not NICE’s formal guidance on this procedure. The recommendations are provisional and may change after consultation.
The process that NICE 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- The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS.
For further details, see the Interventional Procedures Programme manual, which is available from the NICE website.
Through its guidance NICE is committed to promoting race and disability equality, equality between men and women, and to eliminating all forms of discrimination. One of the ways we do this is by trying to involve as wide a range of people and interest groups as possible in the development of our interventional procedures guidance. In particular, we aim to encourage people and organisations from groups who might not normally comment on our guidance to do so.
In order to help us promote equality through our guidance, we should be grateful if you would consider the following question:
Are there any issues that require special attention in light of NICE’s duties to have due regard to the need to eliminate unlawful discrimination, advance equality of opportunity, and foster good relations between people with a characteristic protected by the equalities legislation and others?
Please note that NICE reserves the right to summarise and edit comments received during consultations or not to publish them at all where in the reasonable opinion of NICE, the comments are voluminous, publication would be unlawful or publication would otherwise be inappropriate.
Closing date for comments: 20 June 2014
Target date for publication of guidance: September 2014
1 Provisional recommendations
1.1 The evidence on assessing motility of the gastrointestinal tract using a wireless capsule raises no major safety concerns. There is evidence of efficacy in measuring gastrointestinal function but uncertainty about the clinical benefit of this, and about patient selection. Therefore this procedure should be used only with special arrangements for clinical governance, consent and audit or research.
1.2 Clinicians wishing to assess motility of the gastrointestinal tract using a wireless capsule should take the following actions:
· Inform the clinical governance leads in their NHS trusts.
· Ensure that patients understand the uncertainty about the procedure’s efficacy and provide them with clear written information. In addition, the use of NICE’s information for the public [[URL to be added at publication]] is recommended.
· Audit [URL to audit tool to be added at publication] and review clinical outcomes of all patients having assessing motility of the gastrointestinal tract using a wireless capsule (see section 7.1).
1.3 NICE encourages further research into assessing motility of the gastrointestinal tract using a wireless capsule. Studies should include clear details of patient selection. They should report on the diagnostic accuracy of the procedure in different parts of the gastrointestinal tract, and should provide data on the clinical benefits of the procedure for patients.
2 Indications and current treatments
2.1 The procedure is used to investigate gastrointestinal (GI) motility-related symptoms. In particular, it is intended for use in people with suspected gastroparesis or slow transit constipation. Gastroparesis is a chronic disorder of the stomach, characterised by delayed gastric emptying in the absence of mechanical obstruction. Treatment includes medical therapies (such as antibiotics and metoclopramide), botulinum toxin, gastric electrical stimulation, jejunostomy, and parenteral nutrition. Slow transit constipation comprises a number of symptoms including straining, hard stools, sensation of incomplete evacuation and infrequent bowel movements. Management includes medical therapies such as laxatives and lifestyle advice (for example increasing exercise, and intake of water and fibre).
2.2 The standard procedure used to assess upper GI motility is gastric emptying scintigraphy. It involves ingestion of a standardised radiolabelled meal. An X-ray is taken after 4 hours to determine the extent of gastric emptying.
2.3 Slow transit constipation is diagnosed using a radiopaque marker examination. The patient ingests a number of radiopaque markers and has an X-ray(s) after a predefined time period (usually 4 or 5 days) to determine whether markers have been evacuated.
3 The procedure
3.1 The aim of the wireless capsule procedure is to measure gastrointestinal (GI) motility (that is, gastric emptying time, small bowel transit time and/or colonic transit time) by assessing temperature, pressure and pH.
3.2 The wireless capsule system consists of a single-use, non-digestible, wireless transmitting capsule, a receiver for acquiring and storing signals from the capsule and software for displaying data on a computer. The patient fasts for several hours before the procedure and then drinks some water and eats a standardised meal replacement before swallowing the capsule. The patient then fasts for several more hours and is advised to avoid vigorous exercise. While in the body, the capsule samples bowel contents and transmits data about pH, pressure and temperature to a portable receiver (worn by the patient) at regular intervals as it travels through the GI tract. The patient can record meals, sleep and bowel movements by pushing an event button on the receiver. The capsule is passed out of the bowel with the faeces. If not seen in the stool, loss of the recording signal and/or an abrupt temperature drop on the recording profile confirm exit of the capsule from the body.
This section describes efficacy outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the interventional procedure overview.
4.1 A review of 745 patients (12 studies) with suspected motility problems reported sensitivity of the wireless motility capsule in comparison to clinical diagnosis of gastroparesis to be 65 to 68% and specificity to be 82 to 87% in a subset of 560 patients (reported by 7 studies included in the review).
4.2 The review of 745 patients (12 studies) with suspected motility problems reported sensitivity of the capsule in comparison to gastric emptying scintigraphy to be 59 to 86% and specificity to be 64 to 81% in a subset of 560 patients (reported by 7 studies included in the review).
4.3 The review of 745 patients (12 studies) with suspected motility problems reported sensitivity of the capsule compared with a radiopaque marker to be 37% and specificity to be 95% in a subset of 78 patients (reported by 1 study included in the review) with constipation. A case series of 187 patients with constipation reported sensitivity of the capsule in comparison to radiopaque marker assessment for colonic transit time of 80% (95% CI: 67 to 98%, p=0.01) and specificity of 91% (95% CI: 83 to 96%, p=0.00001). The same study reported sensitivity of the capsule in comparison to radiopaque marker assessment for small and large bowel transit time of 79% (95% CI: 67 to 89%, p=0.01) and specificity of 91% (95% CI: 83 to 96%, p=0.00001).
4.4 A case series of 86 patients with suspected symptoms of upper GI or lower GI dysmotility reported that the capsule confirmed the clinical diagnosis in 58% (50/86) of patients and radiopaque marker examination or gastric emptying scintigraphy confirmed the clinical diagnosis in 44% (38/86) of patients (p<0.05).
4.5 A case series of 83 patients with suspected gastroparesis, intestinal dysmotility or slow transit constipation reported that in 53% (44/83) of patients, using the capsule led to a new diagnosis. In a case series of 43 patients with gastroparesis comparing the capsule with gastric emptying scintigraphy, the reported overall diagnostic gain with the capsule was 19% (p=0.04).
4.6 A review of 745 patients (12 studies) with suspected motility problems reported data from a subset of 3 studies. In these 3 studies, using the wireless capsule altered management (medicine, diet or surgery) in 50 to 69% of patients with suspected gastroparesis in a subset of 3 studies.
4.7 The specialist advisers listed key efficacy outcomes as pan enteric measurement of transit and motility measurements in gut regions.
This section describes safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the interventional procedure overview.
5.1 Device malfunction was reported in 4% (8/180) of those who ingested the wireless motility capsule in the case series of 187 patients with symptomatic constipation.
5.2 Software malfunction resulting in missing data was reported in 7% (12/165) of participants (group not specified) in a comparative study of 165 people (78 patients with chronic constipation versus 87 healthy subjects).
5.3 Capsule retention on X-ray, after 5 days, was reported in 21% (14/67) of patients with constipation in the comparative study of 165 patients. At day 21 X-ray 79% (11/14) of these patients had expelled the capsule. The other 3 recovered the capsule from their stools.
5.4 The case series of 187 patients with constipation reported 7 adverse events as being possibly or definitely related to the capsule; 2 cases of abdominal pain, 1 case of diarrhoea, 2 cases of dysphagia and 2 cases of nausea.
5.5 The specialist advisers stated theoretical adverse events include impaction of the capsule in patients with strictures, and the capsule not progressing beyond the stomach in patients with severe gastroparesis.
6 Committee comments
6.1 The Committee noted the difficulties of validating the accuracy of diagnostic procedures in the gastrointestinal tract, especially for patients with complex motility disorders, in whom a range of diagnostic procedures may be used. These issues contributed to the difficulty in assessing the efficacy of this procedure.
6.2 The Committee noted the particular difficulty of validating diagnostic procedures for motility disorders of the small bowel.
7 Further information
7.1 This guidance requires that clinicians undertaking the procedure make special arrangements for audit. NICE has identified relevant audit criteria and is developing an audit tool (which is for use at local discretion), which will be available when the guidance is published.
Chairman, Interventional Procedures Advisory Committee
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It is the responsibility of consultees to accurately cite academic work in order that they can be validated.
This page was last updated: 20 June 2014