Endoscopic Lung Volume Reduction with One-Way Valves in Patients with Severe Chronic Obstructive Pulmonary Disease with Hypercapnia

Abstract

<b><i>Background:</i></b> Robust clinical evidence on the efficacy and safety of endoscopic lung volume reduction (ELVR) with one-way valves in patients with severe lung emphysema with chronic hypercapnic respiratory failure is lacking. <b><i>Objective:</i></b> The aim of this study was to compare patient characteristics, clinical outcome measures, and incidences of adverse events between patients with severe COPD undergoing ELVR with one-way valves and with either a partial pressure of carbon dioxide (pCO₂) of ≤45 mm Hg or with pCO₂ &#x3e;45 mm Hg. <b><i>Methods:</i></b> This was a multicentre prospective study of patients with severe lung disease who were evaluated based on lung function, exercise capacity (6-min walk test [6-MWT]), and quality-of-life tests. <b><i>Results:</i></b> Patients with pCO₂ ≤45 mm Hg (<i>n</i> = 157) and pCO₂ &#x3e;45 mm Hg (<i>n</i> = 40) showed similar baseline characteristics. Patients with pCO₂ ≤45 mm Hg demonstrated a significant increase in forced expiratory volume in 1 s (<i>p</i> &#x3c; 0.001), a significant decrease in residual volume (RV) (<i>p</i> &#x3c; 0.001), and significant improvements in the quality of life and 6-MWT at the 3-month follow-up. Patients with pCO₂ &#x3e;45 mm Hg had significant improvements in RV only (<i>p</i> &#x3c; 0.05). There was a significant decrease in pCO₂ between baseline and follow-up in hypercapnic patients, relative to the decrease in patients with pCO₂ ≤45 mm Hg (<i>p</i> = 0.008). Patients who were more hypercapnic at baseline showed a greater reduction in pCO₂ after valve placement (<i>r</i> = −0.38, <i>p</i> &#x3c; 0.001). Pneumothorax was the most common adverse event in both groups. <b><i>Conclusions:</i></b> ELVR with one-way valves seems clinically beneficial with a remarkably good safety profile for patients with chronic hypercapnic respiratory failure.