The Facts

Chronic bronchitis belongs to a larger family of medical conditions known as chronic obstructive pulmonary disease (COPD). The term COPD is given to any condition that causes difficulty in breathing as a result of constant blocking of the airways.

Bronchitis is said to occur when the airways in the lungs (bronchial tubes) become partly clogged with large amounts of mucus and become narrowed due to inflammation and swelling. These symptoms typically result in a chronic cough. When cough and sputum have been present for more than three months in each of two consecutive years, the condition is called chronic bronchitis. In North America, about 1 in 20 people suffers from chronic bronchitis. Smoking for many years causes about 90% of chronic bronchitis cases, and thus the great majority of people with chronic bronchitis are over 45 years of age. The risk of chronic bronchitis is also increased in workers employed in certain occupations such as coal mining, welding, asbestos work, or grain handling.

When breathing suddenly becomes more difficult for a person with chronic bronchitis, he or she may be experiencing an acute exacerbation of chronic bronchitis (AECB). During an acute exacerbation, breathing becomes much more difficult because of further narrowing of the airways and secretion of large amounts of mucus that is often thicker than usual.

Causes

The further narrowing of airways in people with chronic bronchitis that results in AECB can be caused by allergens (e.g., pollens, wood or cigarette smoke, pollution), toxins (a variety of different chemicals), or acute viral or bacterial infections. This is because the extra mucus in the airways of a person with chronic bronchitis provides a good place for viruses and bacteria to grow. Bacterial infections are usually associated with mucus that turns a yellow or greenish colour and is typically much thicker than usual. Coloured mucus does not necessarily mean the person has a bacterial infection, however.

Symptoms and Complications

An acute exacerbation of chronic bronchitis is associated with increased frequency and severity of coughing, and is often accompanied by worsened chest congestion and discomfort. If the acute exacerbation is due to a bacterial infection, the sputum may be slightly streaked with blood and coloured yellow or green. In many cases of AECB, shortness of breath and wheezing are present. People suffering from an acute exacerbation caused by infection may feel weak and have fever and chills. Doctors may recommend a chest X-ray for people with fever and especially with blood in their sputum to ensure that pneumonia is not the cause for these symptoms. Blood in the sputum may also indicate other medical conditions and should be reported to your physician promptly.

Making the Diagnosis

An acute exacerbation of chronic bronchitis is said to have occurred if there has been an increase in frequency and severity of cough, along with larger amounts of sputum that may be thicker than usual, but without evidence of pneumonia. The bigger challenge lies in diagnosing the cause of an acute exacerbation of chronic bronchitis so that the best treatment can be put in place. Therefore, it is important for the person with AECB to report a clear picture to their doctor of the circumstances that may have led to the particular episode. For example, was there exposure to inhaled irritants such as second-hand smoke in the recent past? It is also extremely important to accurately describe symptoms to the doctor (e.g., fever, chills).

Your physician may investigate your AECB with a chest X-ray or a sputum culture. Treatment is often started before the test results confirm the condition.

Treatment and Prevention

Prevention of AECB for a person with chronic bronchitis includes:

• quitting smoking and avoiding dust, second-hand smoke, and other inhaled irritants
• yearly immunization against influenza and pneumonia
• regular exercise, appropriate rest, and healthy nutrition as discussed with health professionals
• avoiding people who currently have an infectious respiratory disease such as a cold or influenza
• maintaining good fluid intake and humidifying the home to help reduce the problem of thick sputum and chest congestion

Treatment of AECB may include:

• cough suppressants, which may be used to reduce the severe coughing that can occur with AECB. Expectorants may be used to help liquefy thick mucus, making it easier to clear it from the airways. Drinking plenty of fluids will also help to thin mucus.
• inhaled bronchodilator treatment. Bronchodilators such as salbutamol* and terbutaline, and another inhaled medication called ipratropium, open up the airways in the lungs.
• treatment with antibiotics if a bacterial infection is the suspected cause. Antibiotics will not help infections caused by viruses. Viral infections will usually go away on their own with the aid of proper rest and care. However, other medications may be needed to control symptoms.
• treatment with corticosteroids such as prednisone. These medications reduce inflammation in the airways and are usually used for short periods of time when an acute exacerbation occurs.
• an oral (taken by mouth) medication called theophylline. Theophylline helps to ease the difficulty of breathing. If a person with AECB is not already taking theophylline for chronic bronchitis, the doctor may want them to take it to help with the symptoms of an acute exacerbation.
• oxygen therapy if the physician determines that the blood oxygen level is too low. Some people with severe chronic bronchitis require oxygen on an ongoing basis. Portable "home oxygen therapy" allows a person to remain mobile while receiving this therapy.

Any person with chronic bronchitis should have a treatment or "care plan" in place for those times when an acute exacerbation suddenly hits. A doctor and patient must agree on which symptoms to watch for (e.g., shortness of breath, change in character or amount of mucus) before the person starts self-treatment. Such plans allow a person to start treatment right away so symptoms are kept as much under control as possible until a doctor can be seen.

*All medications have both common (generic) and brand names. The brand name is what a specific manufacturer calls the product (e.g., Tylenol^®). The common name is the medical name for the medication (e.g., acetaminophen). A medication may have many brand names, but only one common name. This article lists medications by their common names. For more information on brand names, speak with your doctor or pharmacist.