What is emphysema?

Emphysema is a disease of the lungs that usually develops after many years of smoking. Both chronic bronchitis and emphysema belong to a group of lung diseases known as chronic obstructive pulmonary disease (COPD). Once it develops, emphysema can’t be reversed. This is why not smoking or stopping smoking is very important.

Emphysema is a condition that involves damage to the walls of the air sacs (alveoli) of the lung. Alveoli are small, thin-walled, very fragile air sacs located in clusters at the end of the bronchial tubes deep inside the lungs. There are about 300 million alveoli in normal lungs. As you breathe in air, the alveoli stretch, drawing oxygen in and transporting it to the blood. When you exhale, the alveoli shrink, forcing carbon dioxide out of the body.

When emphysema develops, the alveoli and lung tissue are destroyed. With this damage, the alveoli cannot support the bronchial tubes. The tubes collapse and cause an “obstruction” (a blockage), which traps air inside the lungs. Too much air trapped in the lungs can give some patients a barrel-chested appearance. Also, because there are fewer alveoli, less oxygen will be able to move into the bloodstream.

Who gets emphysema?

Over 3 million people in the United States have been diagnosed with emphysema. Over 11 million Americans have COPD. Emphysema is most common in men between the ages of 50 and 70.

What causes emphysema?

Smoking is the number one factor. Because of this, emphysema is one of the most preventable types of respiratory diseases. Air pollutants in the home and workplace, genetic (inherited) factors (alpha-1 antitrypsin deficiency), and respiratory infections can also play a role in causing emphysema.

Cigarette smoking not only destroys lung tissue, it also irritates the airways. This causes inflammation and damage to cilia that line the bronchial tubes. This results in swollen airways, mucus production, and difficulty clearing the airways. All of these changes can lead to shortness of breath.

What are symptoms of emphysema?

Symptoms of emphysema may include coughing, wheezing, shortness of breath, chest tightness, and an increased production of mucus. Often times, symptoms may not be noticed until 50% or more of the lung tissue has been destroyed. Until then, the only symptoms may be a gradual development of shortness of breath and tiredness (fatigue), which can be mistaken for other illnesses. People who develop emphysema have an increased risk of pneumonia, bronchitis, and other lung infections. See your doctor if any of these symptoms arise:

  • Shortness of breath, especially during light exercise or climbing steps.
  • Ongoing feeling of not being able to get enough air.
  • Long-term cough or “smoker’s cough.”
  • Wheezing.
  • Long-term mucus production.
  • Ongoing fatigue.

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