A small Canadian study has examined for the first time the influence of pursed-lip technique on respiratory distress and endurance in patients with interstitial lung diseases.
We came across a work by scientists from the University of Montréal, Canada, with a simple and practical message: Patients with pulmonary fibrosis, a type of interstitial lung disease (ILD) should be informed that the pursed-lip as a breathing technique can have a negative effect on them during exercise dyspnea.
The small Canadian crossover study involved 35 ILD patients with a total lung capacity of < 80% of target (average forced vital capacity or FVC: 64 ± 10%/target) who served as their own controls: they completed the 6-minute walking test twice in randomized order, once with pursed-lip and once with normal breathing. Ventilation and metabolic parameters were measured using a metabolic cart and data comparison at one-minute intervals.
Using pursed-lip breathing, the respiratory rate was -significantly- lower and the breath volume larger, but the dyspnoea was stronger (5.2 vs. 4.2 points on the 10-point Borg scale) and the distance shorter (403 vs. 429 ). More than 80% of the patients (n = 29) found the pursed-lip less pleasant than normal breathing. In total ventilation and oxygen saturation, there were no relevant differences between the two walking tests. On the other hand, the use of the pursed-lip resulted in a higher average oxygen intake (13.9 ± 3.6 vs 12.9 ± 3.2 mL/kg/min) even after correction of the walking test types.
The authors conclude: In their study, the use of the pursed-lip improved neither the exercise dyspnea of ILD patients nor the walking distance or gas exchange compared to normal breathing, but was associated with a higher metabolic effort. These results cast doubt on the usefulness of pursed-lip breathing for ILD patients, which should be considered when tailoring pneumatological rehabilitation programs for this patient population.
ILD patients should be educated in a differentiated way
Our summary goes as follows:
In summary, given the findings of this study, please inform your ILD patients about the working principles and specific areas of application of the pursed-lip breathing.
Reference:
Parisien-La Salle S al. Effects of Pursed Lip Breathing on Exercise Capacity and Dyspnea in Patients With Interstitial Lung Disease: A randomized cross over study. J Cardiopulm Rehabil Prev 2019;39(2):112-7
Abbreviations:
FVC = forced vital capacity
ILD = interstitial lung disease