At the end of the airways are the alveoli. These tiny airsacs resemble bunches of grapes and this is where the blood stream picks up oxygen and gives off carbon dioxide. Within the muscle surrounded airways takes place most of which concerns the asthmatic. During an asthma attack the muscles around the airways contract, this is one of the body's natural defense mechanisms in reaction to inhaled irritants. In the asthmatic this reaction gets out of control, restricting the flow of air, and causing the asthmatic to become short of breath and the characteristic wheezing sound.
Excess mucus is produced in an attempt to protect the airway.
Unfortunately, in the asthmatic this action also can get out of control. The swelling starts to close off some air passages causing air trapping. The excess mucus becomes thick and overwhelms the cilia, which can only move the thickened mucus slowly and with difficulty, and the asthmatic experiences severe coughing which also causes more irritation to the airways. This is the vicious cycle produced during an asthma attack. Click here to access a list of terms that will help you fully appreciate this website.