"How COPD damages the lungs"

[susanny]

Here is an excellent explanation of how the lungs work and how COPD damages them. It's from JohnsHow COPD Damages the Lungs

Your lungs make oxygen available to your body and remove other gases, such as carbon dioxide. When you inhale, air travels down the back of your throat (pharynx) and passes through your voice box (larynx) and into your windpipe (trachea). The trachea is divided into two air passages (mainstem bronchi); one leads to the left lung, and one to the right lung. The diaphragm, a dome-shaped muscle, lies below the lungs.

The right lung has three sections, called lobes, and is slightly larger than the left lung, which has two lobes. The mainstem bronchi divide into smaller air passages called bronchioles. At the end of the bronchioles are tiny air sacs called alveoli, where oxygen and carbon dioxide are exchanged.

After absorbing oxygen, the blood flows from the lungs to the heart. It is then pumped through the body, providing oxygen to the cells of the tissues and organs. When the cells use the oxygen, carbon dioxide (CO2) is produced and transferred to the blood. The blood carries the CO2 back to the lungs, where it is removed when you exhale.

Your lungs are protected from harmful substances in a number of ways. The hair in the nose helps filter out large particles, and cilia (microscopic hairlike projections on cells that line the nose and larger airways of the lung) continually sweep back and forth to keep the air passages clear. Mucus produced by the trachea and bronchial tubes helps trap dust, bacteria and other foreign substances before they enter the lungs.

In a person who is breathing normally, the airways are open and free from inflammation and excess mucus. In someone with chronic obstructive pulmonary disease (COPD), the lining of the airways becomes inflamed and swollen. The lining can make extra mucus, which clogs the airways. The muscles around the airways tighten, making the airways even narrower. Sometimes the airways can become so narrow that air has trouble getting in and out of the lungs.

* In chronic bronchitis, the lining of the bronchioles becomes inflamed and produces too much mucus. In some people, the swelling and excess mucus narrow the airways and restrict airflow in and out of the lungs, causing shortness of breath. The cilia also are damaged, preventing them from removing the excess mucus. This can result in enhanced mucus production, a chronic cough and, if the airway narrowing is severe, overinflation of the lungs.

* In emphysema, the alveoli are destroyed, making it difficult for the lungs to absorb enough oxygen or rid themselves of enough CO2. The walls of the alveoli lose their elasticity and become enlarged. As they get bigger, the diaphragm flattens, making it harder for the lungs to move air in and out. The bronchioles also become less elastic and become narrow or collapse upon exhalation. As a result, CO2 gets trapped in the airways and prevents oxygen from getting to the blood. Muscles of the upper chest are called into action to assist with the work of breathing, and this adds to the feelings of fatigue.

Want to learn more about COPD?
We can help!

If you or a loved one has COPD, you know first hand how ordinary tasks like walking up a flight of stairs or making your bed can cause wheezing, coughing and pronounced shortness of breath. Our comprehensive report on Treating and Managing Chronic Obstructive Pulmonary Disease (COPD) gets to the heart of your concerns about living with chronic bronchitis or emphysema. It provides the latest thinking on the causes of COPD and the full range of your treatment options -- with discussions of medications, oxygen therapy, pulmonary rehabilitation and surgical interventions. Written by Dr. Enid R. Neptune, Assistant Professor of Medicine at the Johns Hopkins Obstructive Lung Disease Clinic, Treating and Managing Chronic Obstructive Pulmonary Disease (COPD) is a must-have primer for patients and families affected by COPD.

There are a lot of topics of discussion on their website. Below is the link straight to lung disorders:

www.johnshopkinshealthalerts.com/alerts_index/lung_disorders/22-1.html