Focused Pulse High-frequency Chest Wall Oscillation (FP-HFCWO) for Mucus Management in COPD (Chronic Obstructive Pulmonary Disease) and Asthma: A Single-center Cohort Study.

Abstract

Introduction: Mucus hypersecretion is a significant clinical challenge in patients with Chronic Obstructive Pulmonary Disease (COPD) and asthma, often contributing to poor disease control and frequent exacerbations despite maximal pharmacological therapy. Focused Pulse High-Frequency Chest Wall Oscillation (FP-HFCWO) therapy has been proposed as an adjunctive treatment to enhance mucus clearance and improve clinical outcomes. This retrospective cohort study aimed to assess the impact of FP-HFCWO therapy using the Respin 11 device in patients with COPD and asthma presenting with persistent mucus hypersecretion and inadequate disease control.

Methods: A retrospective, single-center analysis was conducted on patients with COPD or asthma attending the pulmonary outpatient clinic at San Carlo di Nancy Hospital in Rome from September 2023 to January 2025. Eligible patients were those receiving maximal inhalation therapy, daily mucolytics, and presenting with mucus hypersecretion, frequent exacerbations or radiological small airways impairment such as tree-in-bud or mucus plug. FP-HFCWO therapy was prescribed for 20 minutes daily, and clinical outcomes were evaluated using the COPD Assessment Test (CAT) and Asthma Control Test (ACT) scores. The effect of FP-HFCWO on CAT/ACT changes and moderate-to-severe exacerbations was evaluated.

Results: A total of 27 patients were included (COPD: n=17, asthma: n=10). The mean age was 74.2 years, with 78.0 for COPD and 67.8 for asthma. Baseline spirometry showed greater obstruction in COPD (FEV₁% predicted: 64.7%) compared to asthma (78.2%). Both groups share a significant small airway involvement on High-Resolution Computed Tomography (HRCT) and a smoking habit. FP-HFCWO significantly improved the clinical burden, CAT scores decreased by a mean of 7.5 points (p<0.001) in COPD, while ACT scores improved by 7.5 points (p<0.001) in asthma. The number of moderate-to-severe exacerbations was reduced by 66.6% in asthma (Δ-1.20 events) and by 73.0% in COPD (Δ-1.11 events), both statistically significant (p<0.001).

Discussion: These findings suggest that FP-HFCWO therapy may serve as a valuable adjunct to standard care in obstructive airway diseases. The observed improvements in symptom scores and reduction in exacerbations support its clinical relevance. Despite the retrospective design and limited sample size, the consistency of benefit across both COPD and asthma groups is noteworthy. This therapy could be considered in selected patients with chronic mucus hypersecretion and poor disease control. Further prospective studies are needed to confirm these promising results and define optimal patient selection criteria.

Conclusion: FP-HFCWO therapy (Respin 11, VitalAire®) demonstrated significant clinical benefits in patients with Chronic Mucus Hypersecretion (CMH) and poor disease control, leading to improved symptom burden and reduced exacerbation frequency in both COPD and asthma populations. These findings support the use of FP-HFCWO as an effective adjunctive therapy in COPD and asthma. However, given the study's limitations, including its retrospective design, small sample size, single-center setting, and short follow-up duration, further large-scale prospective studies are warranted to validate these results and assess long-term benefits.