Smoking Most Common Cause for Deadly Illness
Chronic Obstructive Lung Disease (COPD) is a common problem affecting millions of people in the U.S. COPD accounts for millions of emergency department visits yearly. COPD is reported to be the third leading cause of death in the U.S. It is reported that 90 percent of COPD cases are due to smoking.
In order to understand what COPD is, we have to have a basic understanding of how the lungs work. The lungs’ primary function is to deliver oxygen (O2) to the blood and remove carbon dioxide (CO2). This is known as respiration. The lung is like a complex collection of small air sacks that are surrounded by blood vessels and are connected to air passages. These passages start out large at the wind pipe (trachea) and become progressively smaller as they branch into bronchi and bronchioles.
The lungs have elastic tissue. This allows them to act like a balloon if it were blown up and then released. The lung tissue tends to return to its normal resting shape (like a balloon) after it has been stretched. For normal respiration, the lungs are not stretched open by air being forced into them with positive pressure. Instead, the chest cavity expands as the diaphragm and muscles attached to the ribs work to create a vacuum that pulls air into the lungs. When the muscles relax, the lung returns to its normal resting position and expels the air.
COPD is a disease process that interferes with the lung’s ability to return to its normal shape due to airway obstruction or due to loss of elasticity of the lung tissue. The obstruction can be due to constriction of bronchi due to muscle contraction or due to inflammation causing mucous and swelling. Asthma is a form of obstructive lung disease. Acute symptoms can occur in response to an allergen. Sometimes, the symptoms are persistent and become a chronic problem. Emphysema is a result of loss of the elasticity of the lung tissue causing the lung to be unable to return to its normal shape. This is like a balloon that has been inflated and stretched over and over so it becomes flimsy.
COPD can be caused by genetic conditions linked to lung disease. However, the great majority of COPD cases are caused by smoking. Smoking damages and inflames the lining of the bronchi causing a buildup of mucous and swelling referred to as chronic bronchitis. It injures the small hair-like structures that sweep mucous and debris out of the bronchi. Smoking also damages the elastic tissue of the lung.
Smoking causes damage that accumulates over years. Some people are more prone to the damage from smoking than others. Much of the damage that is done by smoking is irreversible. The damage comes on so gradually that many smokers do not realize how bad their lung function is until it is too late. COPD decreases life expectancy especially in the more severe cases. As the disease progresses, the ability to exchange O2 and CO2 is impaired so that oxygen levels drop and CO2 levels rise in the blood.
COPD due to asthma is usually responsive to inhaled medications, like albuterol, to relax the airway constriction. Ipratropium is another inhaled medication used to open airways. Also, steroid medications can be inhaled or taken orally to reduce the inflammation. People with COPD are much more prone to infections like pneumonia. Antibiotics are needed at times to treat bacterial lung infections. In severe cases, oxygen supplementation may be necessary. Unfortunately, the response to medications is not as effective for people who have chronic damage from smoking.
The majority of COPD can be avoided by not smoking. Quitting will help symptoms and decrease progression of the disease process but, unfortunately, damage to the lungs is not completely reversible. Not smoking or quitting smoking is a critical step in staying healthy my friends.
Michael Shattuck, MD, is an emergency department physician at ThedaCare Medical Center-Berlin.
