During normal respiration, air travels through the nose, down the trachea, and into smaller and smaller airways called bronchi. The bronchi divide into bronchioles and finally into tiny grape-like clusters of thin, fragile sacs called alveoli. In alveoli, oxygen is exchanged for carbon dioxide in the blood.
Inhaled toxic vapors, such as those found in cigarette smoke, can lead to the development of emphysema, an irreversible disease that jeopardizes the lungs’ ability to function.
Emphysema destroys the alveoli and the alveolar ducts. As your lungs lose elasticity, the alveoli rupture, creating large airspaces that reduce the surface area needed by your body to absorb oxygen and remove carbon dioxide waste. This can cause shortness of breath that progressively worsens and results in damage to the lungs and the heart.