Chronic obstructive pulmonary disease is made up of two primary components, emphysema and chronic bronchitis. Emphysema is a disease that causes the hardening of the air sacs in the lungs. They not only lose their ability to expand and take in oxygen, but also to transfer what oxygen they do receive into the bloodstream. This is a common disease of smokers. The other primary component is chronic bronchitis. Chronic bronchitis is an inflammation of the bronchial tubes inside the lungs, causing them to shrink and be unable to bring oxygen into the body.
While eventually the entire lung will be affected, it has been shown that the upper portion of the lungs develops more emphysema damage than the lower portions, making that the most commonly removed section during surgery.
The disease is broken into three stages (depending on the amount of lung function a patient retains):
Stage I: Patient retains 50 percent or better of expected lung function. Stage II: 35-49 percent. Stage III: 35 percent or less.
Lung function is determined by pulmonary function tests. The most common is the forced expiratory volume test, which measures how much air a person can push out while exhaling.
Patients are counseled to avoid triggers such as smoke or smoking and dust. Medications can be used to halt the progression of the disease; however, there is no way to cure COPD. There are two classes of medication used: bronchodilators and corticosteroids. Bronchodilators reduce the inflammation in the bronchial tubes, releasing the tightness in the chest and allowing more oxygen in. Corticosteroids are meant to treat acute cases, though they are not meant to be used long term due to their side effects.
Most COPD is controlled through lifestyle changes and medication, though surgery is a possibility in extreme cases. A lung transplant is the most extreme surgery available to those suffering from the disease.