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 (pCO<sub>2</sub>) of ≤45 mm Hg or with pCO<sub>2</sub> >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 pCO<sub>2</sub> ≤45 mm Hg (<i>n</i> = 157) and pCO<sub>2</sub> >45 mm Hg (<i>n</i> = 40) showed similar baseline characteristics. Patients with pCO<sub>2</sub> ≤45 mm Hg demonstrated a significant increase in forced expiratory volume in 1 s (<i>p</i> < 0.001), a significant decrease in residual volume (RV) (<i>p</i> < 0.001), and significant improvements in the quality of life and 6-MWT at the 3-month follow-up. Patients with pCO<sub>2</sub> >45 mm Hg had significant improvements in RV only (<i>p</i> < 0.05). There was a significant decrease in pCO<sub>2</sub> between baseline and follow-up in hypercapnic patients, relative to the decrease in patients with pCO<sub>2</sub> ≤45 mm Hg (<i>p</i> = 0.008). Patients who were more hypercapnic at baseline showed a greater reduction in pCO<sub>2</sub> after valve placement (<i>r</i> = −0.38, <i>p</i> < 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.

Recent advances in bronchoscopic lung volume reduction for severe COPD patients

“…Remarkably, arterial blood gas analysis at follow-up showed that 40% of the patients had a normalized pCO 2 , probably due to improved respiratory mechanics effectuated by the reduction in hyperinflation. These conclusions were also supported in a multicentre trial by Lenga et al 14 ,. showing a greater reduction in pCO 2 after valve placement in patients who were more hypercapnic at baseline when compared to normocapnic patients.…”

Response to endobronchial valve treatment: it's all about the target lobe

“…This is consistent with previous publications that showed that patients with baseline measures below (previously) recommended selection criteria (such as residual volume ≤175% pred [ 23 ] or FEV 1 ≤20% pred [ 24 , 25 ]) can also significantly benefit from EBV treatment [ 5 ]. Furthermore, EBV treatment was found to be safe and clinically beneficial in patients with a lower level of D LCO (≤20% pred [ 26 , 27 ]) or clinically relevant hypercapnia (partial pressure of carbon dioxide ≥45 mmHg [ 28 , 29 ]). Of course, it would be helpful, especially for pulmonary physicians starting up a lung volume reduction programme at their hospital to have guidance on patient selection and thus clear cut-off values on standard baseline measures such as pulmonary function outcomes.…”

“…Furthermore, EBV treatment was found to be safe and clinically beneficial, inpatients with a lower level of DLCO (≤20% of predicted) [27,28] or clinical relevant hypercapnia (pCO2≥ 45mm Hg). [29,30] Of course, it would be helpful, especially for pulmonary physicians starting up a lung volume reduction programme at their hospital to have guidance on patient selection and thus clear cut-off values on standard baseline measures such as pulmonary function outcomes. However, our results, together with these previous publications suggest that using strict selection criteria might lead to undertreatment of potential responders and that it is more important to look at the bigger picture in which the 'quality' of the target lobe plays a critical role.…”