Effect of high-flow nasal therapy during exercise training in COPD patients with chronic respiratory failure: study protocol for a randomised controlled trial

Background

The benefit of pulmonary rehabilitation (PR) in symptomatic chronic obstructive pulmonary disease (COPD) is well known. However, advanced patients with chronic respiratory failure (CRF), a category excluded from most studies, are frequently unable to sustain a work-load sufficiently high to obtain the full benefit of PR on exercise tolerance. Recent studies involving heated and humidified high flow oxygen therapy (HFOT) showed positive effects on breathing pattern and ventilatory efficiency during effort. We thus plan to compare, in COPD patients with CRF undergoing a high-intensity exercise programme, the effect of using HFOT versus standard oxygen delivery via Venturi Mask (V-mask), at the same inspiratory oxygen fraction, on improving exercise endurance.

Methods/Design

This is a multicentre randomised controlled trial that will involve 156 COPD inpatients with CRF recruited from seven PR hospitals. Patients will be randomised to one of two groups – V-mask versus HFOT. All patients will undergo the same high-intensity exercise programme using either of the oxygen delivery devices as per their group allocation. Training will consist of 20 sessions, over 1 month (5 sessions per week) within the hospitalisation period. Anthropometric and clinical data, including body mass index, diagnosis, spirometry and comorbidities (Cumulative Rating Scale) will be collected at baseline. At baseline and at the end of the exercise programme (primary assessment time) evaluation will include exercise tolerance (Constant Work Rate Exercise Test) (primary outcome), functional capacity (6-min walk test), maximal inspiratory pressure/maximal expiratory pressure, peripheral muscle strength (biceps and quadriceps) by manual dynamometer, respiratory exchanges (blood gases analysis), disability (Barthel Index and Barthel Dyspnoea Index), impact of disease (COPD Assessment test), and quality of life (Maugeri Respiratory Failure Scale-26). At the end of the training period, patient satisfaction will be evaluated.

Discussion

This study will add knowledge about the exercise response in advanced COPD with CRF and verify if an alternative tool, namely HFOT, can increase the benefit obtained from PR.

Trial registration

ClinicalTrials.gov ID NET03322787

Registered: 6 November 2017

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3440-2) contains supplementary material, which is available to authorized users.

Методи дослідження ефективності фізичної терапії та легеневої реабілітації осіб з хронічним обструктивним захворюванням легень (аналіз систематичних оглядів)

Вступ. У більшості сучасних протоколів легеневої реабілітації та менеджменту пацієнтів із ХОЗЛ подано рекомендації щодо діагностичних методів дослідження та обґрунтування показників з урахуванням стратегії лікування. Недостатніми є рекомендації щодо методів дослідження та показників, які доцільно використовувати як критерії ефективності фізіотерапевтичного втручання. Мета дослідження. Проаналізувати методи дослідження, що найчастіше використовують для оцінювання ефективності фізичної терапії та легеневої реабілітації осіб з хронічним обструктивним захворюванням легень. Матеріали і методи дослідження. Проаналізовано 8 систематичних оглядів веб-бібліотеки Cochrane, присвячених фізичній терапії та легеневій реабілітації, які базувалися на аналізі 145 рандомізованих досліджень. Визначено методи дослідження та показники, використані для оцінювання результатів і ефективності фізичної терапії та легеневої реабілітації. Результати. Проаналізовано 550 методів дослідження та показників. Висновки. Більшість методів обстежень, використаних у рандомізованих дослідженнях, які стосуються легеневої реабілітації та фізичної терапії пацієнтів з ХОЗЛ, можна умовно розподілити на такі групи оцінювання: 1) якість життя та його компоненти, прояв симптомів захворювання; 2) рівень фізичної працездатності та витривалості, рухової сфери; 3) стан кардіореспіраторної системи; 4) інтегральні показники; 5) показники госпіталізації, загострень і смертності; 6) показники інформованості, грамотності й освіченості пацієнтів. Жоден окремий метод дослідження не може відобразити різноманіття патогенетичних проявів ХОЗЛ або належно описати характер чи важкість захворювання, дати інформацію про ефективність фізичної терапії. Для всебічного реабілітаційного оцінювання пацієнтів із ХОЗЛ доцільно застосовувати хоча б по одному із методів дослідження з кожної виокремленої групи.

Non-invasive ventilation during exercise training for people with chronic obstructive pulmonary disease

BACKGROUND

Exercise training as a component of pulmonary rehabilitation improves health-related quality of life (HRQL) and exercise capacity in people with chronic obstructive pulmonary disease (COPD). However, some individuals may have difficulty performing exercise at an adequate intensity. Non-invasive ventilation (NIV) during exercise improves exercise capacity and dyspnoea during a single exercise session. Consequently, NIV during exercise training may allow individuals to exercise at a higher intensity, which could lead to greater improvement in exercise capacity, HRQL and physical activity.

OBJECTIVES

To determine whether NIV during exercise training (as part of pulmonary rehabilitation) affects exercise capacity, HRQL and physical activity in people with COPD compared with exercise training alone or exercise training with sham NIV.

SEARCH METHODS

We searched the following databases between January 1987 and November 2013 inclusive: The Cochrane Airways Group specialised register of trials, AMED, CENTRAL, CINAHL, EMBASE, LILACS, MEDLINE, PEDro, PsycINFO and PubMed. 

SELECTION CRITERIA

Randomised controlled trials that compared NIV during exercise training versus exercise training alone or exercise training with sham NIV in people with COPD were considered for inclusion in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion in the review, extracted data and assessed risk of bias. Primary outcomes were exercise capacity, HRQL and physical activity; secondary outcomes were training intensity, physiological changes related to exercise training, dyspnoea, dropouts, adverse events and cost.

MAIN RESULTS

Six studies involving 126 participants who completed the study protocols were included. Most studies recruited participants with severe to very severe COPD (mean forced expiratory volume in one second (FEV1) ranged from 26% to 48% predicted). There was an increase in percentage change peak and endurance exercise capacity with NIV during training (mean difference in peak exercise capacity 17%, 95% confidence interval (CI) 7% to 27%, 60 participants, low-quality evidence; mean difference in endurance exercise capacity 59%, 95% CI 4% to 114%, 48 participants, low-quality evidence). However, there was no clear evidence of a difference between interventions for all other measures of exercise capacity. The results for HRQL assessed using the St George's Respiratory Questionnaire do not rule out an effect of NIV (total score mean 2.5 points, 95% CI -2.3 to 7.2, 48 participants, moderate-quality evidence). Physical activity was not assessed in any study. There was an increase in training intensity with NIV during training of 13% (95% CI 1% to 27%, 67 participants, moderate-quality evidence), and isoload lactate was lower with NIV (mean difference -0.97 mmol/L, 95% CI -1.58mmol/L to -0.36 mmol/L, 37 participants, moderate-quality evidence). The effect of NIV on dyspnoea or the number of dropouts between interventions was uncertain, although again results were imprecise. No adverse events and no information regarding cost were reported. Only one study blinded participants, whereas three studies used blinded assessors. Adequate allocation concealment was reported in four studies.

AUTHORS' CONCLUSIONS

The small number of included studies with small numbers of participants, as well as the high risk of bias within some of the included studies, limited our ability to draw strong evidence-based conclusions. Although NIV during lower limb exercise training may allow people with COPD to exercise at a higher training intensity and to achieve a greater physiological training effect compared with exercise training alone or exercise training with sham NIV, the effect on exercise capacity is unclear. Some evidence suggests that NIV during exercise training improves the percentage change in peak and endurance exercise capacity; however, these findings are not consistent across other measures of exercise capacity. There is no clear evidence that HRQL is better or worse with NIV during training. It is currently unknown whether the demonstrated benefits of NIV during exercise training are clinically worthwhile or cost-effective.