Emphysema is a progressive lung disease. Also known as a chronic obstructive disease it breaks down the tissues which support the lungs’ shape, including the tissue surrounding the alveoli, which means they can’t maintain their shape during exhalation.
The main cause of this disease is tobacco smoking. When toxins, like smoke from a cigarette, get taken into the lungs the particles can get trapped in the alveoli causing them to become inflamed. The chemicals released due to this inflammatory response lead to the alveolar septum breaking down by protease enzymes which digest the protein elastin. This leads to septal rupture which causes the shape of the lungs to become deformed.
The cavity of the lungs becomes larger, containing less alveoli, and the lack of support leads to this space increasing even more. The alveoli area and ventilation decrease which leads to the thoracic cage expanding and the diaphragm contracting to try and compensate. The body now finds it harder to expel carbon dioxide and sometimes even to take in oxygen which can cause people to hyperventilate.
In very serious cases the body vasoconstricts certain vessels which puts extra strain on right hand side of the heart where the lungs pump the deoxygenated blood. The heart muscles thicken in an attempt to pump more blood but, as the heart fails, it increases in size and blood eventually backs up into the liver.
Emphysema is irreversible but can be slowed down if the sufferer stops smoking. Through pulmonary rehabilitation their quality of life can be improved and lung volume reduction surgery is another option. The only real ‘cure’, however, is a lung transplant.