Inside the respiratory system, there are very small sacs of air called alveoli and the passages that lead to these sacs of air are called bronchioles. In pulmonary emphysema, the bronchioles become permanently distended with air. This condition reduces the number of blood vessels because of the loss of elasticity in the lung tissues. Consequently, the ability of the lungs to provide oxygen continues to decrease and the person becomes breathless very easily.

Not all smokers contract emphysema and it also occurs in non smokers. Some feel that the white cells in the lungs produce a substance called elastase. Smoke or dust interferes with the cells causing them to release this elastase. If this happens, it may attack the lung tissue.

Subcutaneous emphysema can also result from a broken rib that punctures the lung or from whooping cough.

Some patients become cyanosed due to a lack of oxygen in the blood. This bluish discolouration is most noticeable on the lips and under the fingernails.

The progress of pulmonary emphysema may be slowed with treatment but it cannot be cured. Some bronchodilator drugs give relief, particularly if the patient also has chronic bronchitis. Breathing pure oxygen from a cylinder allows enough gas to enter the blood stream.

Emphysema can sometimes be slowed but lung damage cannot be repaired, so it is better not to begin smoking.