Emphysema is a condition that makes the act of breathing difficult because the lungs are not able to expand and contract properly. In addition, the lung tissue deterioration that accompanies emphysema impairs the gas exchange that should take place in the lungs. Other COPDs are chronic obstructive bronchitis and chronic asthmatic bronchitis. All COPDs can result in serious breathing difficulty and can be life threatening. Oxygen enters the lungs during inhalation.
Healthy lungs are able to transfer the oxygen to the bloodstream.
Lungs damaged by emphysema are not able to transfer the gases to and from the bloodstream as well as healthy lungs can. Usually this injury results from smoking tobacco. Although the irritants in air pollution can trigger the condition, as can genetic conditions, causes other than tobacco use are rare. In some people, over a period of 20 to 30 years of exposure to a lung irritant, the alveoli become more and more damaged. They enlarge, becoming diseased sacs called bullae, and lose their ability to exchange oxygen and carbon dioxide.