COPD (Chronic Obstructive Pulmonary Disease)
Chronic obstructive pulmonary disease
(COPD) is a group of lung diseases that cause swelling of the airways.
Emphysema and chronic bronchitis are the most common forms of COPD.
Emphysema is a lung disease that involves damage to the air sacs (alveoli)
in the lungs. The air sacs become dilated and are unable to deflate
completely with breathing. This renders them incapable of filling
with fresh air and limits their ability to move oxygen into the bloodstream,
thus decreasing the amount of oxygen that gets to the body tissues.
Bronchitis is an inflammation of the main airways (bronchi) that
persists for a long period of time or recurs repeatedly. It is characterized
by a cough that is productive of mucus for 3 months or more in at
least 2 consecutive years, without the presence of any other disease
that could account for this symptom.
Causes, incidence and risk factors
The leading cause
of COPD is smoking. Prolonged tobacco use causes lung inflammation
and destroys the air sacs in the lungs. Other risk factors for COPD
are exposure to second-hand smoke, male gender and working or living
in a polluted environment.
- Shortness of breath (dyspnea) persisting
for months to years
- Decreased exercise tolerance
- Cough with or without phlegm
- A chest X-ray can show an over-expanded
lung (hyperinflation), and a chest CT scan may show emphysema.
- A sample of blood taken from an artery (arterial
blood gas/ABG) may show low levels of oxygen (hypoxemia) and high
level of carbon dioxide.
- Pulmonary function
tests show decreased airflow rates while exhaling, and air-trapping.
Treatment includes inhalers that dilate
the airways (bronchodilators), decrease bronchospasm (anticholinergics)
and decrease inflammation (inhaled steroids). Stopping smoking is
essential to effective treatment.
Antibiotics are used in addition to
oral or IV steroids for severe flare-ups. Eventually, oxygen may
be required and lung rehabilitation programs have been shown to be
helpful in some individuals.