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"Does spirometry help detect asthma?"


I think my child has asthma. He is 8 and his pediatrician recommended spirometry. Will this help?


Spirometry is a standard part of pulmonary function tests that are used to help diagnose and follow a number of lung disorders. The basic tests can help measure the amount of air that a person can breathe in and out and how fast the air can be exhaled. These measurements can give doctors a sense of how obstructive or restrictive the lung disease is, which helps ultimately in the choice of medications used to treat it.

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For asthma in particular, the tests can be helpful in assessing the responsiveness of the airway constriction to "bronchodilating" medication such as albuterol. To help make the diagnosis of asthma, a measurement is made of how much air is expelled in the first second of forced exhalation. After a treatment with albuterol, this number should increase (typically by at least 200 milliliters of air and by 12% overall). In addition to helping rule out other diseases of the lung, the spirometry will also allow your doctor to track the progress of your child's breathing as he is exposed to new medications. If he is diagnosed with asthma and requires more inhalers in the future, serial spirometry tests can help determine if he has any residual obstruction caused by the airway constriction and inflammation. I advise that you discuss your questions about spirometry and asthma with your child's pediatrician.

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