Gas exchange can become impaired in individuals with chronic obstructive pulmonary disease. Some mechanisms behind impaired gas exchange in COPD can include one or a combination of the following: airways or alveoli that have lost elasticity and cannot expand and deflate to their full capacity when you breathe in and out, alveoli walls that have been destroyed, leading to reduced surface area for gas exchange, long-term inflammation that’s led to thickening of the airway walls, airways that have become clogged with thick mucus. Impaired gas exchange is often treated using supplemental oxygen. This helps counteract the effects of hypoxemia by delivering oxygen directly into your lungs. You’ll breathe in supplemental oxygen through a nasal cannula or a mask. Depending on the severity of your symptoms, you may need supplemental oxygen all the time or only at certain times. Oxygen therapy needs to be carefully monitored, as it can worsen hypercapnia in some situations. Treatment for hypercapnia involves noninvasive ventilation therapy, often called BiPAP, which is the name of a brand of ventilation therapy machine. During BiPAP, you wear a mask that provides a continuous flow of air into the lungs, creating positive pressure and helping the lungs expand and stay expanded longer. Get the full story at healthline.com.