Abstract
Chronic obstructive pulmonary disease (COPD) is a chronic progressive disease that is characterized by irreversible airflow limitation with a partially reversible component. The pathologic abnormalities of COPD are associated with lung inflammation, an imbalance of proteinases and antiproteinases, and oxidative stress that are induced by noxious particles and gases in susceptible individuals. The physiologic changes of COPD are mucus hypersecretion, ciliary dysfunction, airflow limitation, pulmonary hyperinflation, gas exchange abnormalities, pulmonary hypertension, cor pulmonale, and systemic effects. The airflow limitation results principally from an increase in the resistance of the small conducting airways and a decrease in the pulmonary elastic recoil due to emphysematous lung destruction. This article provides a general overview of the pathophysiology of COPD.
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