Effects of Conical Positive Expiratory Pressure Mask Application During Exercise Training on Pulmonary Rehabilitation Outcomes in Moderate to Severe COPD Cases: A Randomized Controlled Trial.

Abstract

Background: The use of positive expiratory pressure (PEP), which includes conical-PEP breathing, has been proposed for use during exercise among patients with chronic obstructive pulmonary disease (COPD) to reduce dynamic hyperinflation (DH) and improve exercise capacity. However, evidence on the effects of exercise training with conical-PEP for pulmonary rehabilitation (PR) remains limited. This study was conducted to evaluate the aforementioned effects on exercise capacity, DH, and quality of life among patients with moderate to very severe COPD.

Methods: Forty-two patients with moderate to very severe COPD were assigned to a home-based PR program. They were then randomly allocated to exercise training with conical-PEP (n = 21, age 64.5 ± 6.8 years) or without conical-PEP (control group, n = 21, age 67.2 ± 8.0 years) for 8-10 weeks. The outcomes of the 6-min walk distance (6MWD), the endurance spot marching test (ESMT) for endurance time, an inspiratory capacity (IC) test to assess DH, the transition dyspnea index (TDI), St. George's Respiratory Questionnaire (SGRQ), and the COPD Assessment Test (CAT) were recorded at baseline and at the program's end (post-PR).

Results: There were no significant differences in 6MWD (p = 0.116) or ESMT endurance time (p = 0.247) between the conical-PEP and control groups at post-PR. Compared to baseline, the post-PR measurements showed a significant reduction in end-exercise IC in the control group (Δ -0.08 L, 95% CI: -0.16 to -0.01 L, p = 0.033) but no significant reduction in the conical-PEP group (Δ -0.07 L, 95% CI: -0.19 to 0.05 L, p = 0.193). No significant differences were found between the groups at post-PR in terms of TDI (p = 0.277), SGRQ (p = 0.687), or CAT (p = 0.704) scores.

Conclusion: The addition of conical-PEP during exercise training for PR in COPD did not provide significant benefits over exercise training without conical-PEP. Further research is warranted.