The lungs play a critical role in the body, extracting oxygen from inhaled air for distribution via the bloodstream to every cell in the body. Conversely, during exhalation the lungs expel waste -- carbon dioxide produced when cells use oxygen.
The major components of the respiratory system are the bronchi, the larger conducting airways that begin at the end of the trachea and go into the lung; the bronchioles, the more narrow airways that branch from the bronchi; and alveoli, tiny air sacs located at the end of the bronchioles where the exchange of oxygen and carbon dioxide takes place — the respiratory zone. Blood carries oxygen from the respiratory zone to cells and returns carbon dioxide to the respiratory zone for disposal via exhalation.
When lungs become diseased, they no longer can maintain the necessary exchange of oxygen and carbon dioxide. A number of diseases and conditions can cause lungs to become so dysfunctional that one or both of them may need to be replaced through transplantation. These can include:
This disease, which mainly includes chronic bronchitis and emphysema, involves obstruction of airflow through the airways and out of the lungs. COPD is usually permanent and progressive.
ILD is a general term that includes many chronic lung disorders in which the lung is damaged, the walls of the air sacs become inflamed and then scarring (i.e., pulmonary fibrosis) begins in the tissue between the air sacs (interstitium). This causes the lungs to become stiff and smaller in volume.
This genetic disease is characterized by the production of abnormal secretions and damage to airways, leading to mucus build-up that impairs respiration when it occurs in the lungs.
In this disorder, the airways become enlarged and distended, forming pockets where infection can develop. As a result, the lining of the airways become altered, which damages the lung's cleaning system and causes dust, mucus and bacteria to accumulate and infection to occur.
This rare disorder in which the pressure in the pulmonary circulation is above normal levels can cause permanent damage to the lungs and become life-threatening. When there is no known cause, it is called primary pulmonary hypertension. Pulmonary hypertension that occurs as a result of other disorders is called secondary pulmonary hypertension. Pulmonary hypertension caused by and abnormal development and defects in the heart and great vessels is called Eisenmenger's syndrome.
A systemic disease in which chronic inflammation causes granulomas (small lumps) to develop in body tissues — often in the lungs.
This rare disease is characterized by a proliferation of muscle cells that cause the airways, blood and lymph vessels to become obstructed.
For in-depth information on thoracic diseases and disorders, click here to visit NewYork-Presbyterian/Columbia University Medical Center's General Cardiothoracic Surgery site.