Functional and prognostic effect of dynamic airway collapse in patients with chronic obstructive pulmonary disease

Abstract

Background Chronic obstructive pulmonary disease (COPD) is a disease characterized by diffuse airway obstruction affecting small and large airways. Airway collapse is more during expiration. Aim To investigate excessive expiratory airway collapse and its frequency in patients with COPD, with correlation to clinical and functional parameters. Patients and methods The study was carried out at Chest Department, Zagazig University Hospital during the period from August 2017 to August 2018. It included 40 patients with COPD meeting GOLD criteria. All patients underwent pulmonary function tests and low-dose computed tomography scan at three times: at end inspiration, at end expiration, and at dynamic expiration. The degree of dynamic airway collapse is evaluated and correlated with GOLD stage, clinical data, and BODE index. Results There is a negative correlation between forced expiratory volume in 1 s% predicted with the dynamic airway collapse at the arch of the aorta (r=−0.72, P=0.000), at bronchus intermedius (r=−0.06, P=0.000), and with the dynamic airway collapse at carina (r=−0.32, P=0.03). There is a significant difference among different GOLD scale categories regarding dynamic collapse at aortic arch (P=0.000) and dynamic collapse at bronchus intermedius (P=0.000), with no correlation with other physiological parameters or the need of noninvasive positive pressure ventilation or mechanical ventilation. Conclusion Dynamic airway collapse is not infrequent in patients with COPD, and it can affect patients’ pulmonary functional parameters and disease severity but does not affect the overall prognosis.

Keywords

• collapse
• chronic obstructive pulmonary disease
• computed tomography
• excessive dynamic airway collapse