An Overview of Emphysema

Emphysema is a chronic lung disease caused by damage to the alveoli, the tiny air sacs in the lung where the exchange of oxygen and carbon dioxide takes place. With emphysema, damage to the alveoli results in air becoming trapped.

Emphysema is classified as a type of chronic obstructive pulmonary disease (COPD), which also includes chronic bronchitis and bronchiectasis.

As a result of the progressive damage to alveoli, people with emphysema will experience a decreased level of oxygen in the blood (called hypoxemia) combined with an increased level of carbon dioxide in the blood (called hypercapnia).

Emphysema primarily affects the lungs but can also affect other organ systems, including the heart, muscles, and circulatory system, as the disease progresses.

Depending on the stage of the disease and other factors, the symptoms of emphysema may include:

• Shortness of breath (dyspnea)
• A persistent cough 
• The production of sputum or phlegm
• Wheezing
• Frequent respiratory infections (including pneumonia)
• Chest pain
• Cyanosis (bluish fingers and lips due to low oxygen in the blood)

In addition to respiratory symptoms, emphysema can also lead to exercise intolerance and muscle atrophy. The combination of decreased exercise and chronic respiratory stress can promote lean muscle loss, especially in the core muscles. This can create a downward spiral where core muscle weakness only increases the severity of respiratory symptoms.

Finally, emphysema is characterized by what is known as COPD exacerbations. These are periods when symptoms become worse and require hospitalization. Exacerbations may be precipitated by infections or exposure to air pollution, wood smoke, or even perfume.

People with emphysema are also at an increased risk of developing lung cancer.

If your COPD symptoms are worsening, speak with your doctor about the possibility of lung cancer. Lung cancer is far more curable when diagnosed in the early stages of the disease.

Smoking is the most common cause of emphysema, thought to be responsible for 85 percent to 90 percent of the cases. But there are many other causes which can act alone, or in conjunction with smoking, to cause emphysema.

While we can't be entirely sure why some people get COPD and others don't, several risk factors have been identified, including:

• Secondhand smoke
• Occupational exposures to fumes, dust, and vapors
• Air pollution
• Asthma

The diagnosis of COPD is often suspected through a careful history and physical examination and then confirmed by pulmonary function tests (PFTs).

Various factors may alert a doctor to a potential diagnosis of COPD. These factors include a patient feeling short of breath at rest or with exercising, and/or a patient experiencing a chronic cough with or without phlegm production.

A history of significant smoking, especially more than 30 to 40 pack-years, or a history of significant exposure to various air pollutants or occupational dust are additional factors that may raise suspicion for a diagnosis of COPD.

Physical exam findings in emphysema will vary depending on the severity of the disease. While the physical exam is often normal in the early stages of the disease, over time, the following findings may appear:

• Decreased breath sounds
• Wheezing and crackles at the lung bases
• Distant heart sounds
• Use of accessory muscles of respiration and exhaling through pursed lips (in advanced emphysema)

Pulmonary function tests, especially a test called spirometry, are needed to confirm the diagnosis of COPD.

Emphysema is irreversible and progressive over time, so the goals of emphysema treatments are slowing the progression of the disease and improving symptoms.

Some treatments include:

There are no drug treatments that have proven successful in slowing the rate of decline of lung function with emphysema. Instead, the medications are used to help increase exercise tolerance, reduce COPD exacerbations, and improve overall health status.

Medications used for stable COPD include:

• Bronchodilators
• Glucocorticoids
• Antibiotics for infections

This can be given continuously, during activity, or for the relief of sudden episodes of shortness of breath. Long-term oxygen therapy of over 15 hours per day is given when a patient has low oxygen saturation levels during advanced (stage IV) COPD.

This is very important for individuals living with this condition and can help to slow the progression of the disease.

There are many benefits of pulmonary rehabilitation, an interdisciplinary program that should last at least six weeks. Pulmonary therapy can make a big difference for people living with emphysema by improving exercise tolerance, reducing symptoms, and decreasing hospitalizations and lengths of stay.

Staying up to date with immunizations, especially the flu vaccine and the pneumonia vaccine, helps prevent infections which can result in worsening the disease.

Emphysema creates a vicious circle. The disease itself makes it difficult to exercise, and the atrophy of muscles can, in turn, make the disease worse. The best exercises for COPD include a combination of endurance, flexibility, and strength training.

Lung volume reduction surgery to remove severely damaged tissue may be useful for some people with severe emphysema, especially for those who have disease predominantly involving the upper lobes. Bullectomy may be done in patients who have giant bullae. Lung transplant is another consideration.

Emphysema can be a frustrating disease all the way around. Not only do you have to cope with symptoms and treatments, but those symptoms and treatments can affect nearly every other area of your life. Unfortunately, many people with COPD receive inadequate support. 

At the current time, emphysema remains an irreversible disease and treatment is aimed at slowing the progression and complications related to the disease. Research in lung regeneration therapy is ongoing and may help develop new treatments for COPD in the future.