Understanding COPD

What is COPD?

COPD stands for chronic obstructive pulmonary (lung) disease. COPD is a term applied to a family of diseases that includes emphysema, chronic bronchitis, and emphysema due to alpha-1 antitrypsin deficiency. COPD usually progresses gradually, causing limited airflow in and out of the lungs.

COPD adds to the work of the heart. Diseased lungs might reduce the amount of oxygen that goes to the blood. High blood pressure in blood vessels from the heart to the lungs makes it difficult for the heart to pump. Lung disease can also cause the body to produce too many red blood cells, which might make the blood thicker and harder to pump.

Patients who have COPD with low oxygen levels might develop an enlarged heart (cor pulmonale). This condition weakens the heart and causes increased shortness of breath, and swelling in the legs and feet.

The good news is that COPD is treatable, and the information in this manual can help you manage your COPD and flare-ups, and help you to modify your risk factors.

Chronic bronchitis

Chronic bronchitis is irritation and inflammation (swelling) of the lining in the bronchial tubes (air passages). The irritation causes coughing and an excess amount of mucus in the airways. The swelling makes it difficult to get air in and out of the lungs. The small, hair-like structures on the inside of the airways (called cilia) might be damaged by the irritation. The cilia are then unable to help clean mucus from the airways.

Bronchitis is generally considered chronic when you have: a productive cough (cough up mucus) and shortness of breath that lasts about three months or more each year for two or more years in a row. Your doctor might define chronic bronchitis differently.

Emphysema

Emphysema is the destruction, or breakdown, of the walls of the alveoli (air sacs) located at the end of the bronchial tubes. The damaged alveoli are not able to exchange oxygen and carbon dioxide between the lungs and the blood. The bronchioles lose their elasticity and collapse when you exhale, trapping air in the lungs. The trapped air keeps fresh air and oxygen from entering the lungs.

Who is affected by COPD?

Emphysema and chronic bronchitis affect approximately 16 million people in the United States, or close to 11 percent of the population.

Symptoms of COPD

• Shortness of breath
• Shortness of breath with mild exercise (walking, using the stairs, etc.)
• Chronic, productive cough (with mucus)
• A feeling of "tightness" in the chest
• Wheezing

What causes COPD?

The two primary causes of COPD are cigarette smoking and alpha-1 antitrypsin (AAT) deficiency. Air pollution and occupational dusts might also contribute to COPD, especially when the person exposed to these substances is a cigarette smoker.

Cigarette smoke causes COPD by irritating the airways and creating inflammation that narrows the airways, making it more difficult to breathe. Cigarette smoke also causes the cilia to stop working properly so mucus and trapped particles are not cleaned from the airways. As a result, chronic cough and excess mucus production develop, leading to chronic bronchitis.

In some people, chronic bronchitis and infections can lead to destruction of the small airways, or emphysema.

AAT deficiency, an inherited disorder, can also lead to emphysema. Alpha-1 antitrypsin (AAT) is a protective material produced in the liver and transported to the lungs to help combat inflammation. When there is not enough of the chemical AAT, the body is no longer protected from an enzyme in the white blood cells. This can cause a breakdown in the walls of the air sacs (alveoli). When the alveoli are destroyed, oxygen cannot be transferred into the blood and carbon dioxide cannot be taken from the blood to be exhaled.

How is COPD diagnosed?

Medical history

To diagnose COPD, the physician needs the answers to the following questions:

• Do you smoke?
• Have you had chronic exposure to dust or air pollutants?
• Do other members of your family have lung disease?
• Are you short of breath?
• Do you get short of breath with exercise?
• Do you have chronic cough and/or wheezing?
• Do you cough up excess mucus?

Physical exam

To help with the diagnosis, the physician will conduct a thorough physical exam, which includes:

• Listening to your lungs and heart
• Checking your blood pressure and pulse
• Examining your nose and throat
• Checking your feet and ankles for swelling

Laboratory and other tests

Several laboratory and other tests are needed to confirm a diagnosis of COPD. These tests might include:

• Electrocardiogram (ECG or EKG) to check heart function and rule out heart disease as a cause of shortness of breath
• Chest X-ray to look for lung changes that could be caused by COPD
• Spirometry and pulmonary function tests (PFTs) to determine lung volume and air flow
• Pulse oximetry to measure the saturation of oxygen in the blood
• Arterial blood gases (ABGs) to determine the amount of oxygen and carbon dioxide in the blood
• Exercise testing to determine if the oxygen level in the blood drops during exercise

Treatment

In the beginning stages of COPD, there is minimal shortness of breath that might be noticed only during exercise.

As the disease progresses, shortness of breath might worsen, and you might need to wear an oxygen device.

To help control other symptoms of COPD, the following treatments and lifestyle changes might be prescribed:

• Quitting smoking
• Avoiding cigarette smoke and other irritants
• Taking medications including:

-bronchodilators
-anti-inflammatory agents
-oxygen
-antibiotics

• Maintaining a healthy diet
• Following a structured exercise program
• Preventing respiratory infections
• Controlling stress

If your COPD progresses, you might be eligible to be evaluated for lung volume reduction surgery or lung transplantation.

You might also be eligible to participate in certain clinical trials (research studies). Ask your health care providers about studies being conducted in your hospital.

What is the outlook?

Although COPD cannot be cured, its symptoms can be treated and your quality of life can be improved. Your prognosis, or outlook, for the future will depend on how well your lungs are functioning, your symptoms, and how well you respond to and follow your treatment plan.

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