Chronic obstructive pulmonary disease Health Article

Definition

Chronic obstructive pulmonary disease (COPD) is lung disease that makes it difficult to breathe. There are two main forms of COPD:

• Chronic bronchitis, which causes long-term swelling and a large amount of mucus in the main airways in the lungs
• Emphysema, a lung disease that destroys the air sacs in the lungs

Most people with COPD have symptoms of both.

Alternative Names

COPD; Chronic obstructive airways disease; Chronic obstructive lung disease; Chronic bronchitis; Emphysema; Bronchitis - chronic

Causes, incidence, and risk factors

Smoking is the leading cause of COPD. The more a person smokes, the more likely that person will develop severe bronchitis. Secondhand smoke may also cause chronic bronchitis. Air pollution, infection, and allergies make chronic bronchitis worse.

In rare cases, nonsmokers who lack a protein called alpha-1 antitrypsin can develop emphysema.

Other risk factors for COPD are:

• Exposure to certain gases or fumes in the workplace
• Exposure to heavy amounts of secondhand smoke and pollution
• Frequent use of cooking gas without proper ventilation

Symptoms

• Cough that produces mucus - may be streaked with blood
• Fatigue
• Frequent respiratory infections
• Headaches
• Shortness of breath (dyspnea) that gets worse with mild activity
• Swelling of the ankles, feet, or legs, which affects both sides
• Wheezing

Some people may have few or no symptoms.

Signs and tests

The health care provider make hear wheezing or abnormal breathing sounds when listening to the chest and lungs with a stethoscope. However, lung sounds can be normal during the exam.

In severe cases, a person with COPD can seem anxious and may breathe through pursed lips (the shape lips make when you whistle).

During a flare up, the muscles between the ribs contract while the person is breathing in. This is called intercostal retractions. The person will use other muscles to breathe. The number of breaths per minute (respiratory rate) may be high.

The best test for COPD is lung function testing.

A chest x-ray may show that the lung is expanding too much. A chest CT scan may reveal emphysema.

A sample of blood taken from an artery (arterial blood gas) can show low levels of oxygen and high levels of carbon dioxide (respiratory acidosis).