COPD (Chronic Obstructive Pulmonary Disease) refers to a set of lung disorders that make breathing difficult and worsen over time.The airways and air sacs in your lungs are normally elastic or stretchy. When you inhale, the airways transport air to the air sacs.Like a little balloon, the air sacs inflate with air. When you exhale, the air sacs deflate and the air escapes. If you have COPD, less air moves into and out of your airways due to one or more of the following issues: your lungs airways and air sacs become less elastic, Many of the air sacs' walls have been damaged; the airway walls thicken and become irritated.
