Detection of Dynamic Lung Hyperinflation

Abstract

Chronic obstructive pulmonary disease (COPD) is the general term for what has traditionally been referred to as chronic bronchitis and emphysema. COPD is commonly caused by inhaling toxic substances, harmful gases, and air pollution. COPD is an irreversible pathology that causes airflow obstruction and ventilation impairment. Until now, there is no complete treatment for COPD, and the main focus is on symptomatic treatment to improve symptoms and delay pathological progression. Airflow obstruction in COPD is caused by a decrease in pulmonary elastic contractile pressure due to peripheral airway involvement and emphysematous lesions, resulting in collapsed airways and the trapping of air in the lungs during forced expiration (referred to as unk or unk air trapping). Air trapping caused by collapsed peripheral airways strengthens with exertion or exercise, causing further lung hyperinflation. In COPD, dynamic lung hyperinflation (DLH) is one of the most significant determinants of short of breath (SOB) on exertion and exercise capacity. It is also an essential determinant in patients with significant lung hyperinflation and emphysema-dominant COPD. Measurement of DLH requires expensive equipment and instruments and is rarely evaluated in routine clinical practice. This review provides a summary of methods for measuring DLH, reaffirms how DLH and its therapeutic effects can be evaluated in routine practice, and outlines new methods that are being proposed.