Overview
Emphysema is a degenerative disease that usually develops after many years of assault on lung tissues from cigarette smoke or other toxins that pollute the air. These toxins destroy the small air sacs in the lungs, called alveoli, that stretch as they transport oxygen from the air to the blood and then shrink as they force out carbon dioxide. As a result, the lungs lose their elasticity, and exhaling becomes difficult as the damaged lungs trap air and cannot effectively exchange it with fresh air. As the damage progresses, the effort needed to breathe increases and, ultimately, each breath becomes labored.
Emphysema is one of a group of lung diseases referred to as chronic obstructive pulmonary disease (COPD) that can interfere with normal breathing. Other diseases that come under COPD include asthma and chronic bronchitis. According to the American Lung Association (ALA), nearly 16 million Americans are estimated to suffer from some form of COPD, and COPD is the fourth-ranking cause of death just behind heart ailments, cancers, and stroke.
ALA estimates that 2 million Americans had emphysema in 1998, and cigarette smoking was the primary cause. Exposure to air pollution and irritating fumes and dusts on the job are also thought to be contributing factors of emphysema.
Symptoms
The predominant symptom of emphysema is shortness of breath or the feeling of not being able to get enough air. A person may initially visit the doctor because he or she has begun to feel short of breath during activity, but as the disease progresses, this symptom may be present all the time, even while sitting quietly. Coughing, wheezing, and chronic mucus production are other common symptoms.
Diagnosis
A diagnosis, however, cannot be based on these symptoms alone. A careful history focusing on the number and duration of these symptoms, as well as smoking and occupational histories, is basic to diagnosing the disease.
The physician will thoroughly examine the chest, observe breathing patterns, and monitor how hard the person is working to breathe. A thorough exam will also include noting the degree of over-inflation of the lungs, listening to the chest with a stethoscope to hear the airflow in and out of the lungs, and listening to heart sounds to determine its rate and rhythm and any signs of heart strain that may accompany advanced stages of emphysema.
In addition, routine lung function tests can determine several characteristics and capabilities of the lungs. The following tests can identify various stages of emphysema:
Spirometry
Through a tube connected to a machine that records airflow and capacity, the patient takes a deep breath and blows it out as quickly as possible. Measuring the amount of air that can be forced out in one second and the total amount of air that can be exhaled is the best way to determine the amount of airways obstruction.
Arterial Blood Gas (ABG)
An ABG is done by analyzing blood from an artery for amounts of carbon dioxide and oxygen. This test is often used to assess more advanced stages of emphysema and to determine whether or not a person needs extra oxygen.
Pulse Oximetry
A special light, clipped onto the finger or earlobe, can indirectly measure the amount of oxygen in the blood.
X-rays
X-rays are not often helpful in early-stage diagnosis of emphysema, but in moderate to severe cases, a reasonably accurate diagnosis can be made with the plain chest x-ray and computerized axial tomography (CAT) scanning. Some of the more common appearances on the chest x-ray include flattened diaphragms, loss of blood vessel markings, and the appearance of a reduced size of the heart.
These and other test results are then compared to values considered healthy for various age groups, heights, weights, genders, and races.
Treatment
There are a number of treatments that can help patients with emphysema, but the most important step is to stop smoking. Stopping smoking when the airflow obstruction is mild or moderate slows the development of disabling shortness of breath. However, stopping smoking at any point in the disease process provides some benefit. People with emphysema should also try to avoid exposure to other airborne irritants.
Treatments include:
Bronchodilator medicines
This class of medication works by relaxing the muscles around the airways. They are typically indicated for the relief of bronchospasm in patients with reversible obstructive airways disease. More commonly used to treat asthma, they may be prescribed for emphysema patients if there is a tendency toward airway constriction or tightening. Some of the more common bronchodilator medicines include: albuterol, terbutaline, ipratropium bromide, and theophylline. Inhaled medicines, which go directly into the lungs and have less exposure to other parts of the body, are often tried first because they usually begin working in less than five minutes with a lower incidence of side effects.
Valuable additions to bronchodilator therapy are blood tests used to monitor pharmacological agents such as theophylline. Although tests for measuring theophylline have been available for decades there continue to be refinements in this testing which make them more accurate and accessible.
Anti-inflammatories (corticosteroids)
Since emphysema may be associated with inflammation, doctors may prescribe a corticosteroid to soothe and ultimately heal the delicate lining layer of the air passageways, making them more resistant to obstruction. Inhaled steroids do not carry an FDA-approved indication for COPD but are used off-label by many clinicians. The type of steroid contained in these preparations is not the type that builds muscles. Long-term use of oral corticosteroids is commonly associated with a variety of dose-dependent side effects, such as osteoporosis (in both men and women), weight gain and fat redistribution, hypertension, loss of lean body mass, and high blood sugar. Commonly used corticosteroids include the oral preparation prednisone and several inhaled corticosteroids.
Oxygen therapy
Supplemental oxygen can benefit the patient whose lung function is severely impaired and cannot absorb enough oxygen from the air. Long-term oxygen therapy prolongs life in patients like Gooden, who have low blood oxygen levels (hypoxemia). This therapy reduces the excess red blood cells, which helps improve mental functioning and heart failure. It may also improve shortness of breath during exercise.
Lung reduction surgery
Emphysema sufferers may find relief from their symptoms with this surgical procedure. It often eliminates the need for oxygen and significantly enhances breathing function. This technique, which is a minimally invasive procedure, requires two or three small incisions made in the chest and a tiny camera inserted through one of the incisions to view the lung. Through another incision, a special stapling device is inserted to cut portions of the lung so that the healthy lung tissue has more room to expand. Prospective patients need to undergo careful testing prior to consideration of this surgery.
Transplant surgery
A lung transplant is a highly invasive, complex procedure that carries substantial risk. Because of known complications of any organ transplant surgery, this option is only viable in a very small, select group of patients.
Exercise programs can be carried out to improve a person's independence and quality of life, and decrease the frequency and length of hospital stays, even though lung function doesn't improve. Gains in conditioning, though, are quickly lost if a person stops exercising.