ASTMA IN CHILDREN: WHAT GOES WRONG ?
WHAT GOES WRONG in the asthmatic lungs? First, let us look at the walls of the bronchial tube. These walls are made up of various cells, muscle tissue, and mucus-secreting glands. In a normal lung, air moves in and out of these bronchial tubes freely, and the air exchange in the alveoli maintains a perfect balance of oxygen and carbon dioxide throughout the entire body.
In a person suffering from asthma, the bronchial tubes become swollen and narrow. Hundreds of thousands of cells in the walls of the bronchial tubes, called mast cells, (discussed later in the chapter) secrete toxic chemicals, called mediators. These chemicals cause the walls of the bronchial tubes to swell up, and the bronchial muscles go into a spasm. The result is a swollen, inflamed, obstructed bronchial tube that blocks the passage of air in and out of the lungs.
When air moves in and out of these obstructed and inflamed tubes, typical symptoms of asthma—coughing and wheezing—occur. Since the bronchial tube is constricted or narrow, the flow of air is obstructed, and the air passing through the narrow obstructed passage produces a hissing or a wheezing sound.
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