This is the second in my series for people who have just been diagnosed with COPD (and their caregivers). It will deal with what to expect physically now that you know you have this disease. COPD stands for Chronic Obstructive Pulmonary Disease. Let's break that down:

• Chronic. This means the disease, once it starts, does not go away. There is no cure.
• Obstructive. This means your airways are partially blocked, making breathing difficult.
• Pulmonary. That means it is a disease of the airways or respiratory system. Pulmonary is another medical term meaning respiratory.

Also, it's important to understand that COPD is what is known as a progressive disease. That means that it will slowly get worse over time. To understand these effects, it's helpful first to know how the airways (lungs) work.

How Healthy Airways Work

When you breathe in air, it goes down your windpipe (trachea) into tubes in your lungs called bronchial tubes, or airways. These airways are shaped like an upside-down tree with many branches that get smaller and smaller. At the end of the branches are tiny air sacs called alveoli (al-VEE-uhl-eye).

The airways and air sacs are elastic. As you breathe in, each air sac fills up with air like a small balloon. When you breathe out, the air sac deflates and the air goes out.

In these air sacs, there is an exchange of oxygen and carbon dioxide. Your cells throughout your body use the oxygen to work and make energy. Carbon dioxide is a waste product that your airways then carry out of your body when you exhale.

What Happens in the Airways When You Have COPD

In COPD, less air flows in and out of your airways because one or more of the following has happened:

• The airways and air sacs lose their elastic quality.
• The walls between many of the air sacs are destroyed.
• The walls of the airways become thick and inflamed (swollen).
• The airways make more mucus than usual, which tends to clog the airways.

Here is an illustration to help you understand the changes:

The end result is that breathing becomes more labored and when you do breathe, not as much oxygen and carbon dioxide are exchanged. So the body does not receive all of the oxygen it needs and carbon dioxide can build up inside your body too.

So breathing is not only harder to do; it's also less efficient.

How This Makes You Feel

Like any disease, symptoms can vary. I'm going to talk in generalities here, but your experience may differ somewhat. Still, most people will have the same or similar effects from COPD.

Symptoms actually can begin years before you realize that your air flow in and out of your lungs has been compromised. This can include:

• A chronic cough that may be dry, but often produces large amounts of mucus (often called "smoker's cough")
• Shortness of breath, especially with physical activity
• Wheezing (a whistling or squeaky sound when you breathe)
• Chest tightness

Some of these symptoms can also be caused by other diseases (such as asthma), but your doctor can test and examine you to figure out if COPD is the culprit.