What is a primary consequence of emphysema?

• A. Poor gas exchange
• B. Increased lung capacity
• C. Enhanced oxygen uptake
• D. Improved airway resistance

Answer: (A)

The primary consequence of emphysema is poor gas exchange. Emphysema is characterized by the destruction of the alveoli, the tiny air sacs in the lungs where gas exchange occurs. This destruction leads to a decrease in the surface area available for oxygen and carbon dioxide exchange, resulting in impaired oxygen uptake and difficulty in eliminating carbon dioxide from the bloodstream. As a result, patients often experience symptoms such as shortness of breath and reduced exercise tolerance due to this ineffective gas exchange.

In contrast, the other options do not accurately represent the consequences of emphysema. The condition does not lead to increased lung capacity; in fact, lung capacity may appear increased due to hyperinflation, but effective capacity for gas exchange is diminished. There is no enhanced oxygen uptake; rather, the opposite is true due to the alveolar damage. Lastly, airway resistance is often increased in emphysema due to loss of elastic recoil, not improved. Thus, poor gas exchange is the significant consequence that arises from the pathophysiological changes associated with emphysema.