The effect of intrapulmonary percussive ventilation on clinical parameters and the deposition of inhalation products in patients with stable COPD

Abstract

Background: Intrapulmonary percussive ventilation (IPV) has demonstrated efficacy in acute settings for treating chronic obstructive pulmonary disease (COPD) exacerbations. Its routine use as an airway clearance technique in stable COPD patients lacks strong scientific support.

Purpose: This study assessed the impact of 4 weeks of IPV treatment in nonhospitalized patients with stable COPD by clinical endpoints, parameters obtained by quantified CT-thorax and a deposition study of inhaled compounds.

Methods: In this prospective study, ten stable patients with severe to very severe COPD were recruited. Each patient received IPV treatment three times a week for four weeks in addition to their existing treatment. The baseline and posttreatment assessments included a chest CT scan, lung function tests, the Clinical COPD Questionnaire (CCQ), and a 6-minute walking distance (6MWD). Dyspnea was scored using the Borg scale. The CT endpoints included mucus plug count and volume, lobe volume, airway volume, proportion of pulmonary blood in small pulmonary vessels (BV5%), and deposition of inhaled triple therapy (beclomethasone, formoterol, glycopyrronium) and a short-acting bèta2 mimetica (SABA) (salbutamol). The Wilcoxon signed rank test was used to determine significant differences. To take into account regional differences, an additional mixed model analysis at the lobar level was performed.

Results: In total, 9 patients (5 M/4 F) completed the study. The 6MWD increased from 329 m to 379 m (p = 0.008). The patient-reported outcomes, measured by the CCQ, tended to improve. The mucus plugs volume and count declined in patients with high baseline values. A decrease in lobe volume at the lobar level, measured at the TLC (p = 0.003), and an increase in lobe volume at the lobar level, measured at the FRC (p = 0.003), were observed. At the lobar level, BV5% decreased (p = 0.044). The distal deposition of triple therapy and SABA medication increased by 11% and 9%, respectively.

Conclusion: IPV for 4 weeks in patients with stable chronic obstructive pulmonary disease had a positive effect on exercise capacity and patient-reported outcomes. This effect is likely due to decreased hyperinflation, recruitment of small airways, mucus clearance, ameliorated gas exchange and increased distal deposition of inhaled therapy. IPV is a promising treatment for patients with severe to very severe COPD.

Keywords: Chronic obstructive pulmonary disease; Functional respiratory imaging; Intrapulmonary percussive ventilation.

Fig. 1

Quantifying changes in mucus plug volume and count. A decrease in the blood vessel volume of the small pulmonary vessels of 1.25 to 5 mm² in the cross-sectional area of the intrapulmonary vessels was observed at the lobar level (p = 0.044). Furthermore, the study revealed a decrease in volume at the lobar level, measured at the TLC (p = 0.003), and an increase in lobe volume at the lobar level, measured at the FRC (p = 0.003). Accordingly, the airway volume at TLC decreased significantly overall and at the lobar level. The airway volume at the FRC increased, but the difference was not statistically significant.

Fig. 2

Deposition of inhaled triple therapy and SABA at Visits 1 and 2. Distal deposition was calculated as the proportion of the delivered dose of inhaled compounds provided using computational fluid dynamics (CFD). This revealed an increase in the distal deposition of inhaled triple therapy and short-acting bèta2 mimetica of 11% and 9%, respectively, as depicted in Fig. 2