EC Pulmonology and Respiratory Medicine

Background: Chronic Obstructive Pulmonary Disease (COPD) is a complex pathological respiratory condition characterized by a range of heterogeneous disorders that variably affect the airways and/or lung parenchyma, with significant morbidity, mortality and socio-economic impact. This underlying heterogeneity results in distinct clinical phenotypes that are rarely investigated in routine clinical practice using standard spirometric parameters. The Emphysema Severity Index (ESI) is a lung function parameter recently developed to evaluate the presence and severity of the emphysema component in COPD patients using standard spirometry. ESI is derived from a biomechanical model of the airways, which analyzes the shape of the descending slope of the maximal expiratory flow-volume (MEFV) curve. The consistency of ESI following bronchodilation has not yet been examined. This study aimed to evaluate the effect of bronchodilation on ESI computation in COPD patients.

Methods: Parameters such as FEV₁, FVC, FEV₁/FVC, RV, TLC, RV/TLC, PEF, MEF (75%, 50%, 25%), and ESI were measured before and 30 minutes after inhalation of 400 mcg of salbutamol in COPD patients, and the results were compared.

Results: A total of 51 COPD patients (31 males [60.8%], mean age 70.4 ± 12.2 years, mean BMI 25.6 ± 4.7) were automatically and anonymously selected from the database based on inclusion and exclusion criteria. All parameters reflecting parenchymal involvement, including RV, TLC, Motley index, and ESI in particular, remained completely unchanged following bronchodilation.

Conclusion: Bronchodilation does not significantly impact the computation of ESI in COPD patients.

 Keywords: COPD; Emphysema; Airway Obstruction; Bronchodilation; ESI

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