Pursed Lip Breathing in Interstitial Lung Disease

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

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.

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.

In this arm, patients will be asked to perform a six-minute walking test while continuously using the pursed lip breathing technique.

In this control arm, patients will be asked to perform a six-minute walking test while breathing normally.

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.

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

Parisien-La Salle S, Abel Rivest E, Boucher VG, Lalande-Gauthier M, Morisset J, Manganas H, Poirier C, Comtois AS, Dube BP. Effects of Pursed Lip Breathing on Exercise Capacity and Dyspnea in Patients With Interstitial Lung Disease: A RANDOMIZED, CROSSOVER STUDY. J Cardiopulm Rehabil Prev. 2019 Mar;39(2):112-117. doi: 10.1097/HCR.0000000000000387.