Chronic obstructive pulmonary disease
COPD, Chronic Airway Obstruction, Asthma, Emphysema
What is Chronic obstructive pulmonary disease?
Chronic obstructive pulmonary disease (COPD) is a group of lung disorders characterized by obstruction of the outflow of air from the lungs. The obstruction may be caused by an anatomical and/or functional disorders of the lung. It does not improve significantly over time. Other names used for the same group of disorders are chronic obstructive lung disease (COLD) and chronic airway obstruction (CAO). Emphysema and chronic bronchitis are types of COPD.
Occasionally, asthma is referred to as a type of COPD, particularly chronic asthmatic bronchitis, which has characteristics of both asthma and bronchitis. Because of the varied and overlapping nature of the diseases included under COPD, it is important that a more specific diagnosis be obtained to assess treatment, prognosis, and any disabling factors.
Over 14 million Americans are afflicted with COPD. The most prevalent diagnosis is chronic bronchitis. There is significant research that suggests cigarette smoking is a major cause of COPD. The risk of developing COPD is 10 to 30 times higher in smokers compared to non-smokers, and the decline of lung function is directly related to the amount of smoking. Other risk factors are air pollution, environmental and occupational exposures, genetic predisposition, airway hyperactivity, and exposure to second hand smoke as a child.
Asthma and chronic bronchitis occur between the ages of 18 and 65. Emphysema occurs in individuals over 45, the majority of whom are over 65 years old.
How is it diagnosed?
COPD signs and symptoms
Symptoms may not appear until middle-age even though COPD is thought to begin early in adult life.
- Frequent cough or coughing spasms usually with sputum.
- Shortness of breath.
- Sputum that is thick and difficult to cough up. Sputum color and characteristics change according to whether infection is present.
- No symptoms in the early stages (often).
- Shortness of breath that increases in severity over several years.
- Occasional recurrent infections of the lungs or bronchial tubes.
- Weight loss.
- Minimal wheezing or coughing.
- Scant sputum.
History includes shortness of breath with exertion, cough, wheezing, frequent colds, and a history of smoking.
Physical exam in the individual with emphysema usually reveals a barrel chest, rapid and labored breathing, rapid heart rate, atrial tachycardia, and normal skin color; breath sounds are faint.
Individuals with chronic bronchitis have less distressed breathing, but the skin may appear blue; breath sounds indicate secretions in the airways (rhonchi).
Tests: Chronic obstructive pulmonary disease is specifically diagnosed by pulmonary function tests (PFTs). Simple spirometry can be done in the doctor's office to confirm COPD.
The diagnosis, classification of severity, prognosis, and guidance of treatment is determined by a complete PFT done in a standardized PFT laboratory. PFTs will show decreased airflow with normal lung volumes and diffusing capacity in the bronchitic individual and decreased airflow with increased residual lung volumes and decreased diffusing capacity in the emphysematous individual.
Blood gas analysis is another indicator of severity of disease.
A chest x-ray can also provide information on the severity of COPD.
How is Chronic obstructive pulmonary disease treated?
The general treatment goals for Chronic obstructive pulmonary disease are to optimize lung function, slow down or stop disease progression, prevent acute flare-ups and complications, and maintain quality of life. Specific treatment includes smoking cessation, bronchodilators, antibiotics, supplemental oxygen, and occasionally corticosteroids. Certain treatments may be used chronically and others may be added during acute exacerbation or infections. A few individuals may be candidates for surgical removal of large bullae or for lung transplantation.
What might complicate it?
The two most serious complications of Chronic obstructive pulmonary disease are right-sided heart failure (cor pulmonale) and respiratory failure. Exposure to inhaled irritants, high altitudes, cold air, the common cold, sinusitis, acute bronchitis, pneumonia or other pulmonary infections will worsen the already existing symptoms of COPD. If the impairment is severe enough, the individual may succumb to respiratory failure. Most COPD individuals recover from their first few episodes of respiratory failure. However, episodes of respiratory failure that occur more frequently are signs of the last stages of this chronic disease. Some COPD individuals develop single or multiple large irregular shaped air spaces called bullae. These bullae can be large enough to compromise good portions of the lung by crowding and compressing them. They can also break, causing an accumulation of air in the chest cavity (pneumothorax) that further compromises pulmonary function.
If smoking is stopped during the early stages of COPD, some of the damage in the small airways may return to normal. Individuals with mild COPD that is treated early may be free of disability, except for acute worsening during other illnesses. Individuals with severe COPD will continue to have progressively deteriorating lung function despite treatment and usually become permanently disabled.
Other conditions with some similarities are pneumonia, a tumor of the throat or lungs, acute bronchitis, bronchiectasis, asthma, allergies, occupational lung disease, heart disease, cystic fibrosis, sarcoidosis, pulmonary fibrosis, pulmonary emboli, and pulmonary edema.
Pulmonologist, allergist, and thoracic surgeon (only if surgery is indicated).
Notify your physician if
- You or a family member has symptoms of COPD.
- A fever develops or chest pain increases.
- Blood appears in the sputum or sputum thickens.
- Shortness of breath occurs even when you are resting or not coughing.
Last updated 22 December 2011