Insertion of endobronchial nitinol coils to improve lung function in emphysema

Emphysema is a progressive lung condition in which the small air sacs (alveoli) inside the lungs break down, resulting in abnormally large air spaces. These large spaces can compress surrounding airways and restrict the flow of air to healthy parts of the lung, making it difficult to breathe. Insertion of endobronchial nitinol coils aims to improve lung function by reducing the size of the diseased areas in the lungs, allowing air to reach healthy areas.

The National Institute for Health and Care Excellence (NICE) is examining the insertion of endobronchial nitinol coils to improve lung function in emphysema 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 the insertion of endobronchial nitinol coils to improve lung function in emphysema.

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• The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS.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: Tuesday 23rd of September 2014

Target date for publication of guidance: December 2014

 

 

 

 

1                      Provisional recommendations

1.1                  Current evidence on the safety and efficacy of the insertion of endobronchial nitinol coils to improve lung function in emphysema is limited in quantity and quality. Therefore the procedure should only be used in the context of research.

1.2                  Research studies should describe patient selection in detail. Outcome measures should include lung function, dyspnoea score, exercise tolerance, quality of life and long-term safety. Studies should also report on the influence of the procedure on subsequent lung surgery.

1.3                  NICE may review the procedure on publication of further evidence.

 

 

 

 

2                      Indications and current treatments

2.1                  Emphysema is a chronic lung disease, which is usually related to smoking but may also be inherited. It is one of a group of diseases referred to as chronic obstructive pulmonary disease (COPD). Common symptoms of emphysema are dyspnoea, coughing, fatigue and weight loss.

2.2                  Current treatment options include pulmonary rehabilitation (guidance on smoking cessation, patient and carer education, exercise training and breathing retraining) and use of inhaled or oral bronchodilators and glucocorticoids. Some patients benefit from oxygen treatment. In advanced disease, lung volume reduction surgery (thoracoscopic or open) or lung transplantation may be needed.

 

 

 

 

3                      The procedure

3.1                  Insertion of endobronchial nitinol coils is intended as a minimally invasive alternative to lung volume reduction surgery. The procedure reduces the volume of diseased areas of the lungs. This limits airflow to the least functional diseased lung segments, allowing air to flow to healthier parts of the lungs, with the aim of improving gas exchange and, as a result, lung function. The procedure is intended for patients with severe upper or lower lobe predominant emphysema, as well as patients with non-severe homogeneous emphysema.

3.2                  Insertion of endobronchial nitinol coils can be performed with the patient under general anaesthesia or sedation. The bronchial tree of the diseased area of the lung is visualised by bronchoscopy and a low-stiffness guidewire is advanced through the bronchoscope under fluoroscopic guidance. A catheter is then passed over the guidewire. The guidewire is removed and a straightened coil is introduced through the catheter. The catheter is withdrawn while the coil is held in place using a grasper. When released, the straightened coil springs back to a predetermined shape, pulling on the surrounding diseased tissue and so reducing lung volume. Typically up to 10 coils are used. The coils are intended to remain in place permanently.

 

 

 

 

 

4                      Efficacy

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 randomised controlled trial of 47 patients compared patients treated by endobronchial nitinol coils (n=24) against patients who received usual care (n=23; treatment included inhalers, bronchodilators, inhaled steroids and pulmonary rehabilitation). Mean baseline St George’s Respiratory Questionnaire scores (scores range from 0 to 100 with lower scores indicating better quality of life) decreased by 8.11 points (from 65.17) in the endobronchial nitinol coil group and increased by 0.25 points (from 53.12) in the usual care group at 3-month follow-up (p value between groups=0.04). In the same study, St George’s Respiratory Questionnaire scores improved by more than 8 points in 57% (13/23) of patients in the endobronchial nitinol coil group and 17% (4/23) of patients in the usual care group at 3-month follow-up (p=0.01).

4.2                  In the randomised controlled trial of 47 patients treated by endobronchial nitinol coils or usual care, mean modified Medical Research Council dyspnoea scores (scores range from 0 to 4 with lower scores indicating decreasing breathlessness) decreased by 0.24 points and 0.09 points respectively, at 3-month follow-up (p value between groups not significant). Baseline values were not reported.

4.3                  In the randomised controlled trial of 47 patients treated by endobronchial nitinol coils or usual care, mean baseline forced expiratory volumes in 1 second (FEV₁) were 0.72 litres and 0.78 litres respectively. At 3-month follow-up, FEV₁ increased by 14.19% and 3.57% respectively (p value between groups=0.03). An improvement of at least 10% in FEV₁ values was observed in 57% (13/23) of patients in the endobronchial nitinol coil group and 26% (6/23) of patients in the usual care group (p value not significant).

4.4                  In the randomised controlled trial of 47 patients treated by endobronchial nitinol coils or usual care, mean baseline total lung capacity values decreased by 0.24 litres (from 7.97 litres) and by 0.13 litres (from 8.02 litres) respectively, at 3-month follow-up (p value between groups not significant).

4.5                  In a case series of 16 patients, the mean distance walked in 6 minutes increased by 35.4 metres (from 338 metres), 1 month after an initial endobronchial nitinol coil treatment, and by 69.8 metres 1 month after a second endobronchial nitinol coil treatment (p values<0.05). The mean distance walked in 6 minutes increased from baseline by 84.4 metres 6 months after a final endobronchial nitinol coil treatment (p<0.05).

4.6                  Specialist advisers listed key efficacy outcomes as reduction in the frequency of chronic obstructive pulmonary disease exacerbations, as well as improvements in exercise capacity (for example, 6-minute walk test), lung function (for example, forced expiratory volume in 1 second, forced vital capacity and residual volume) and quality of life (for example, St George’s Respiratory Questionnaire).

 

 

 

 

5                      Safety

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                  Pneumothorax was reported after 5% (2/44) of endobronchial nitinol coil procedures and in no patients who had usual care (including inhalers, bronchodilators, inhaled steroids and pulmonary rehabilitation) at 1-month follow-up in a randomised controlled trial of 47 patients treated by endobronchial nitinol coils (n=24) or usual care (n=23).

5.2                  Exacerbations of chronic obstructive pulmonary disease were reported in the randomised controlled trial of 47 patients after 5% (2/44) of endobronchial nitinol coil procedures and in 4% (1/23) of patients who had usual care, at 1-month follow-up. At 3-month follow-up, exacerbations of chronic obstructive pulmonary disease were reported after 7% (3/44) of endobronchial nitinol coil procedures and in 9% (2/23) of patients who had usual care.

5.3                  Chest pain was reported after 14% (4/28) of endobronchial nitinol coil procedures, within 1 month of first or second treatment, in the case series of 16 patients. In the same study, chest pain was reported after 7% (2/28) of endobronchial nitinol coil procedures between 1 and 6 months after treatment.

5.4                  Pneumonia was reported after 7% (2/28) of endobronchial nitinol coil procedures, within 1 month of first or second treatment, in the case series of 16 patients. In the same study, pneumonia was reported after 11% (3/28) of endobronchial nitinol coil procedures between 1 and 6 months after treatment.

5.5                  ‘Slight haemoptysis’ was reported after 75% (21/28) of endobronchial nitinol coil procedures, within 1 month of first or second treatment, in a case series of 16 patients.

5.6                  Paroxysmal atrial fibrillation was reported after 4% (1/28) of endobronchial nitinol coil procedures in the case series of 16 patients (time of occurrence not reported). The authors described this as anaesthesia-related. In the same study, phlebitis, headache, hoarseness and bronchospasm were reported after 4% (1/28), 7% (2/28), 11% (3/28) and 4% (1/28) of procedures respectively (time of occurrence not reported). These adverse events were also described as anaesthesia-related.

5.7                  Lower respiratory tract infections were reported in the randomised controlled trial of 47 patients after 5% (2/44) of endobronchial nitinol coil procedures and in no patients who had usual care at 1-month follow-up. At 3-month follow-up, lower respiratory tract infections were reported after 0% of endobronchial nitinol coil procedures and in 4% (1/23) of patients who had usual care.

5.8                  Hypertension was reported in 1 patient, up to 6 months after a first endobronchial nitinol coil treatment, in a case series of 10 patients.

5.9                  Specialist advisers listed bleeding, infection and pneumothorax as anecdotal adverse events. Haemorrhage, coil migration, pneumomediastinum, respiratory failure and the erosion of coils into major vessels were identified as theoretical adverse events.

Bruce Campbell
Chairman, Interventional Procedures Advisory Committee
August 2014