Pursed Lip Breathing in Interstitial Lung Disease

Study Overview
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Brief Summary
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This randomized, cross-over study aims at describing the effect of pursed lip breathing on exercise-induced dyspnea and exercise capacity in patients with interstitial lung disease.

Detailed Description
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The use of pursed lip breathing (PLB) to improve exercise tolerance in COPD patients has been widely documented. However, its efficacy in patients with interstitial lung disease (ILD) has yet to be confirmed. This study aims to determine if PLB improves perceived exertion and exercise capacity during a six-minute walk test (6MWT) in patients with ILD. To achieve this, a prospective randomized crossover trial will be performed, in which patients with ILD and restrictive ventilatory defect will be recruited via the ILD clinic of Hôpital Notre-Dame. The study will be performed in a single visit, on the day where patients attend a routine physician-prescribed follow-up 6MWT. Patients will be asked to perform a total of two 6MWT. Patients will be randomized to perform the first test with or without using PLB, and the order will be reversed for the second test, with patients serving as their own control. During tests, ventilatory variables will be continuously measured using a portable metabolic cart. The observed parameters will be: perceived exertion using the Modified-Borg Scale, respiratory rate, minute-ventilation, heart rate, peripheral oxygen saturation, and 6-minute walk distance (6MWD). It is expected that the use of PLB will be associated with a decrease of at least one unit on the Modified Borg Scale, which would be clinically significant. Moreover, it is expected that the decrease in dyspnea with PLB will be related to a decrease in respiratory rate minute ventilation during 6MWT. The clinical impact of this study could be significant as therapies allowing the improvement of dyspnea in patients with ILD are scarce.

Official Title
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Effects of Pursed Lip Breathing on Exercise Capacity and Dyspnea in Patients With Interstitial Lung Disease: a Randomized Crossover Study

Conditions
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Interstitial Lung Disease

Intervention / Treatment
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* Behavioral: Pursed lip breathing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of interstitial lung disease, based on the results of a multidisciplinary diagnosis discussion. Restrictive ventilatory defect (i.e. total lung capacity (TLC) < 80% of predicted value) on pulmonary function testing. Exclusion Criteria: Active cancer History of severe heart disease Neurological or orthopaedic problem that could interfere with exercise performance Physiological mixed syndromes (i.e. concomitant restrictive and obstructive defects) Exacerbation of disease or hospitalisation in the last 4 weeks prior to enrollment Long-term oxygen therapy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Pursed lip breathing<br>In this arm, patients will be asked to perform a six-minute walking test while continuously using the pursed lip breathing technique. | Behavioral: Pursed lip breathing<br>* Pursed lip breathing will be taught to the participants following the chronic obstructive pulmonary disease (COPD) Foundation recommendations: Breathe in through your nose (as if you are smelling something) for about 2 seconds. Pucker your lips like you're getting ready to blow out candles on a birthday cake. Breathe out very slowly through pursed-lips, two to three times as long as you breathed in. Repeat.<br>|
| No Intervention: Usual breathing<br>In this control arm, patients will be asked to perform a six-minute walking test while breathing normally. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Exertional dyspnea | Patient-reported dyspnea will be measured using the Borg scale | On the day of randomization | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Six-minute walking distance |  | On the day of randomization | 
| Oxygen uptake (ml/min) | Non-invasive real-time measurements will be performed using a portable metabolic cart system. | On the day of randomization, at each minute of the 6-minute walking test | 
| Carbon dioxide output (ml/min) | Non-invasive real-time measurements will be performed using a portable metabolic cart system. | On the day of randomization, at each minute of the 6-minute walking test | 
| Respiratory rate (br/min) | Non-invasive real-time measurements will be performed using a portable metabolic cart system. | On the day of randomization, at each minute of the 6-minute walking test | 
| Tidal volume (ml) | Non-invasive real-time measurements will be performed using a portable metabolic cart system. | On the day of randomization, at each minute of the 6-minute walking test | 
| Minute-ventilation (l/min) | Non-invasive real-time measurements will be performed using a portable metabolic cart system. | On the day of randomization, at each minute of the 6-minute walking test | 
| Peripheral oxygen saturation (%) | Non-invasive real-time measurements will be performed using a portable metabolic cart system. | On the day of randomization, at each minute of the 6-minute walking test | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pursed lip breathing, interstitial lund disease, exercise physiology