Emphysema
Emphysema is a chronic lung disease that is essentially the same as COPD (chronic obstructive pulmonary disease).  It is frequently associated with exposure to toxic chemicals, particularly to cigarette or other tobacco smoke.  Emphysema is caused by a lack of elasticity of the tissue of the lung and secondary destruction of lung tissue.  The alveoli are destroyed along with the lung capillaries.  There is often a lessening of alpha 1-antitrypsin.  The tiny airways collapse on themselves, causing trapped air in the lungs and shortness of breath.  The lungs are expanded because of excess air trapped in the small airways. 
In mild forms of asthma, the person gets by due to hyperventilating.  Such a person is termed a “pink puffer”.  Those who instead suffer from chronic bronchitis are termed “blue bloaters” because they have blue skin and edema of their tissues.  These sufferers breathe because they have too much carbon dioxide and use this fact as a means to continue the drive to breathe. 
Signs and symptoms of emphysema are pursed-lipped breathing, clubbing of their fingers, hyperinflation of the lungs, blue skin and wheezing.  There are also signs of overload of fluid, meaning they have fluid on their ankles and other extremities.  Generally, there are no crackles in the lungs; however, in some patients, there is a fine popping heard on inspiration.
When the emphysema patient fails to hyperventilate enough to maintain enough oxygen, the body compensates by constricting certain vessels.  This leads to high blood pressure in the lungs which strains the right side of the heart, leading to heart failure. As the heart continues to go into failure, the blood backs up into the liver, causing liver enlargement.  
Emphysema occurs to a greater degree in those who suffer from alpha 1-antitrypsin disease.  It is worse if the individual smokes.  In fact, smoking and alpha 1-antitrypsin disease have a 10-15 percent chance of getting emphysema at a very young age.
Causes
Alpha 1-antitrypsin disease plays a small role in the pathogenesis of emphysema.  Other enzymes play a role in the disease and white blood cells are found in higher numbers in the disease.  Emphysema is generally associated with the related diseases of bronchitis and chronic bronchitis.  In fact, it is hard to differentiate between pure cases of chronic bronchitis and emphysema.  They are usually grouped together as the disease COPD. 
Treatment and Prognosis
Emphysema is considered an irreversible condition involving lung degeneration.  The best way to slow its progress is to have the individual quit smoking and avoid any exposure to cigarette smoke of any kind.  Reducing exposure to lung toxins is also an excellent idea.  There exists pulmonary rehabilitation that can improve the function of the lungs. 
Medications used to treat emphysema include bronchodilators that open the airways, anticholinergics that open the lung passages, steroid medication that reduces inflammation and oxygen, if necessary.  Treating acid reflux and any kind of allergies are also good ideas. 
One method of treatment is to use the antioxidant glutathione, which is diminished in many forms of lung disease. The dose is given by means of bronchioalveolar lavage. 
There is surgery for emphysema including lung volume reduction surgery or a lung transplant, provided the person has stopped exposure to smoking.  Transplants are very difficult and result in needing to be on anti-rejection medication, which can cause infection and chronic problems. 
Emphysema is divided into primary and secondary emphysema.  Primary emphysema is divided into panacinary and centroacinary disease.  Panacinary emphysema destroys the lung’s alveoli.  Centroacinary emphysema happens when the terminal bronchioli are destroyed.   This is found in the elderly who develop emphysema.