Emphysema

Emphysema is the first of the two major components of COPD. Healthy lungs are comprised of airways and upwards of 300 million tiny air sacs called alveoli. These alveoli have very thin membranes that allow the oxygen from the air inhaled into the lungs to move into the bloodstream, and for carbon dioxide in the blood to enter the lungs for exhalation. In emphysema, the alveolar membranes become damaged and destroyed and cease to allow this gas exchange to occur. At this time, alveolar damage cannot be regenerated and is regarded as a permanent condition.

Causes

Healthy alveolar membranes are maintained by an intricate balance between two proteins common to the respiratory system. The first protein is an enzyme known as elastase which works to break down elastin (a substance which provides strength to and maintains the elasticity of the alveolar membranes). The second protein is called alpha-1-antitrypsin or AAT. AAT works to inhibit the function of elastase thus protecting existing elastin. In a healthy respiratory system, elastase and AAT activities are balanced so that elastin is not broken down faster than it can be replaced. Emphysema occurs when elastase and AAT activity become unbalanced and elastin gets destroyed faster than it can be replaced. The destruction of elastin results in the alveolar membranes becoming excessively fragile, which then results in the tearing and destruction of the fragile membranes.

There are two major causes or pathways of emphysema: non-familial and familial. Non-familial or "smoker's" emphysema is the most common form, comprising over 80% of all emphysema cases. As its nickname suggests, "smoker's" emphysema is thought to be caused by smoking. Components of tobacco smoke stimulate a heightened release of elastase in the lungs. Tobacco smoke also decreases the effectiveness of the elastase blocker AAT. Familial emphysema is caused by a genetic defect in AAT production which brings about the imbalance and heightened elastase activity characteristic of emphysema. Whether non-familial or familial in origin, both forms of emphysema result in the destruction of alveolar membranes and decreased respiratory function.

Prevention

Regardless of cause, emphysema cannot be cured once initiated, but can be prevented in the first place or slowed in progression through healthy lifestyle choices. Here are some examples of risk factors for emphysema that can be controlled or eliminated by making healthy lifestyle choices:

  • Smoking. Smoking is the single greatest cause of emphysema. The longer someone smokes, the more likely they are to get emphysema. If you currently smoke you should take steps to quit smoking now. Tobacco is an addictive substance, and smokers commonly have a difficult time with stopping smoking. Your doctor may be able to refer you to information about programs and support groups and can provide cessation aids like patches or gums that you can use to help beat your smoking addiction. Stopping your smoking habit now is very important for your health.
  • Airborne Pollutants. You should try to reduce your exposure to airborne pollutants as much as possible. Sources of airborne pollutants include industrial exposures, and secondhand smoke. Individuals who work in settings with high levels of air pollution (miners for example) or who live or work around people who smoke should do as much as possible to protect their respiratory system. People who live in areas with significant air pollution should perform outdoor activities in the morning or evening on days when smog levels are high
  • Good Nutrition. Eating a nutritious diet can help your immune system to stay strong and fight off infection
  • Exercise Regularly. Starting an aerobic (briskly walking, jogging, swimming, etc.) exercise routine is a great way to strengthen both your cardiovascular and respiratory system. Ask your doctor about breathing exercises you can do to further target and strengthen the muscles used in the breathing process. Moderate regular exercise is a great way to boost your energy levels as well as your immune system.

Treatment

People don't tend to recognize common symptoms of emphysema (coughing, shortness of breath) as being serious. It is easy to misinterpret coughing or shortness of breath as evidence you are out of shape or having a cold or virus, for example. However, when respiratory symptoms persist for three consecutive months in two adjacent years or for six months in a single year they may be attributable to a chronic lung disease such as emphysema. Unfortunately, when symptoms have been present this long, permanent lung damage may already have occurred.

While there is no way to reverse the damage emphysema does to the alveoli, doctors can offer treatments to help patients slow the progression of the disease and live a happier, less restrictive lifestyle. Some of the common treatments doctors will employ include the following:

  • Antibiotics. Bacterial infections can often worsen the symptoms of emphysema. For this reason your doctor may prescribe some antibiotic drugs if he or she believes a bacterial infection is present.
  • Bronchodilators. Bronchodilators are a specific type of prescription drug that relax and dilate the bronchial passages in the lungs. Bronchodilators commonly come in the form of inhalable aerosols and oral preparations.
  • Corticosteroids. Like Bronchodialators, corticosteroids relax and open constricted airways. Steroids are often used when bronchodilators have ceased to be effective.
  • Digitalis. Often individuals who have emphysema will also have heart complications. The heart attempts to compensate for a lack of adequate oxygen dissolved in the bloodstream by pumping blood faster. Digitalis, a medication that works to strengthen the contractive force of the heartbeat, is often prescribed to boost the heart's pumping capacity, thereby helping to alleviate the extra stress placed on the heart. Digitalis needs to be used cautiously, as the medicine sometimes is associated with abnormal heartbeats (arrhythmias).
  • Diuretics. Diuretics are substances which cause the body to retain less water than it normally would, excreting the difference as urine. Diuretics can help combat fluid retention caused by pooling of blood inside the heart's chambers. Patients using diuretics must be careful to not allow themselves to become too dehydrated.
  • Oxygen Therapy. The dysfunctional alveolar sacs associated with emphysema leave patients with low levels of oxygen in their bloodstream, and oxygen-starved organs including the brain and heart. Administration of oxygen therapy increases patients' blood oxygen levels, alleviating many symptoms.
  • Lung Volume Reduction Surgery. Also known as LVRS lung volume reduction surgery is a procedure in which the most severely diseased portions of the lung are removed. This allows the healthy regions to function better and more efficiently. This procedure is often not used on individuals who have reached more advanced stages of emphysema because it puts them at a heightened risk of dying.

A diagnosis of emphysema is serious, but does not always mean disability. Patients with emphysema can often continue driving and managing light work around the house. Patients can also often continue to work, unless their work calls for strenuous physical activity, or necessarily occurs in a polluted environment. Your doctor will be in the best position to know what activities of daily life you can perform with safety.