What kind of obstruction is primarily present in COPD?

In Chronic Obstructive Pulmonary Disease (COPD), the primary characteristic of airway obstruction is that it is worse during expiration. This condition is typified by a progressive limitation of airflow, which is particularly apparent when the patient exhales. The underlying pathophysiology often involves chronic inflammation, which leads to narrowing of the airways and parenchymal destruction, making it harder to expel air from the lungs.

During expiration, increased intrathoracic pressure can further compress the narrowed airways, exacerbating the obstruction. Patients may struggle to breathe out, resulting in air trapping and hyperinflation of the lungs. This phenomenon leads to a classic presentation of symptoms, such as breathlessness, especially during physical activities when the demand for airflow increases.

The other aspects of airway obstruction noted in the other choices do not accurately depict the typical patterns seen in COPD. For instance, obstruction that improves with deep inhalation (the first option) is not characteristic of COPD, as the disease primarily affects expiratory airflow, not the inhalation phase. Obstruction occurring at rest (the third option) is misleading, as COPD patients often experience exacerbations, but the obstruction is not defined strictly by being at rest. Lastly, while there is some degree of