The American Thoracic Society defines emphysema as permanent enlargement of the distal airspaces, destruction of their walls, and no obvious fibrosis. Over time, air space becomes deadened with little or no participation in blood–gas exchange. Dyspnea is a hallmark sign of this disorder. About 2 million Americans have this disease; almost 1 million have both chronic bronchitis and emphysema.

Chronic bronchitis involves inflammation of the bronchi (the main passages in the lungs), excessive bronchial mucus production, and a chronic productive cough. Increased mucus volume and consistency impairs mucociliary function in the bronchioles and distal airways. As mucus and inflammation thicken bronchial passages, the risk of infection also increases.

In end-stage chronic bronchitis, the patient may have severe exacerbations, reduced alveolar ventilation, abnormal ventilation-perfusion, hypoxemia (PaO₂ < 50%to 60%), increasing levels of PaCO₂, and polycythemia (compensation for decreased PaO₂).

Treatment and supportive measures for patients with COPD include monitoring of diagnostic criteria and patient education. Because COPD progresses slowly, ongoing monitoring can help you detect changes early and intervene promptly. Monitoring may include:

Urge the patient to avoid smoke and to stop smoking if applicable. Clearly, this task may be very difficult for a patient who has already tried repeatedly to stop smoking. Suggest that the patient also avoid other triggers that could cause COPD to flare up, such as pollution, chemicals, noxious fumes, and infections — although doing so may increase the patient’s sense of isolation and limitation.

Also, teach the patient about the disease process, symptom management, and drug therapy to help manage COPD symptoms. Some patients medically qualify for lung volume reduction surgery, which improves oxygenation and quality of life for about 4 years after it’s performed. Recommend annual flu vaccination and regular vaccination against pneumococcal pneumonia.

The goal of drug therapy is to decrease inflammation in the distal bronchioles and alveoli, aid bronchodilation, decrease mucus production, and treat infection if needed. Drug therapy can’t stop changes that have already occurred in the lung tissue, but it can relieve some symptoms.



Bronchodilators, (including beta₂ agonists, anticholinergics, and methylxanthines), leukotriene inhibitors, mucolytics, and corticosteroids are used most often. (See Drugs for chronic obstructive pulmonary disease.)