COPD is actually two diseases of the lungs: emphysema and chronic bronchitis. Learn more in this video.

Video Transcription

Chronic obstructive pulmonary disease kills over 100,000 Americans each year, making it the fourth leading cause of death in the United States. Chronic obstructive pulmonary disease or COPD refers to two different diseases of the lung—emphysema and chronic bronchitis. Since chronic bronchitis and emphysema affect two different parts of the lung, let us take a separate look at each of these diseases. Chronic bronchitis is characterized by an inflammation of the bronchial tubes, which are passageways that branch off from the trachea or windpipe and allow air to enter the lungs. This inflammation causes thick mucus to build up in the tubes preventing sufficient air from reaching the lungs. Emphysema occurs when the walls between the air sacs in the lungs known as alveoli lose their elasticity. This in turn, causes the air sacs to become fragile and over inflated leading to an unnatural retention of air within the lungs.