Asthma and Your Child
When lungs are healthy, breathing is easy. With each breath, air goes down the windpipe into the lungs. There, it flows through airways (bronchial tubes). The airways make mucus to trap and help get rid of any particles that are breathed in. Muscles that wrap around the airways control how open or closed they are. Air is breathed in and out through the same airways.
How Asthma Affects the Lungs
When airways are healthy and open, there is plenty of room for air to pass in and out of the lungs.
When asthma is uncontrolled, airways are inflamed most of the time. The lining of the airways swells. Muscles around the airways may be tight. Air has to go through a narrower tube. Inflammation makes airways oversensitive to things in the air that are breathed in.
When sensitive airways become irritated, they become even more swollen. The bands of muscle around the airways tighten. More mucus forms. All of this narrows the airways even more. This causes breathing trouble—an asthma flare-up.