This is a test used to evaluate for exercise-induced asthma. Patients with exercise-induced asthma can have cough, chest tightness, or wheezing after exercise. The diagnosis is often difficult to verify based on symptoms alone. The eucapnic voluntary hyperventilation test will determine whether you have exercise-induced asthma. It typically takes about an hour. If you develop asthma during the test, a bronchodilator (albuterol) will be given to you by an inhaler to treat the asthma. This test will be performed by a respiratory therapist and a physician will be available in the building should any problems occur.
A breathing test is initially done to measure the amount of air that you can quickly blow out in the first second (FEV1). You will then be aseked to hyperventilate while breathing a dry gas mix of room air that contains 5% carbon dioxide for 6 minutes. The FEV1 is then measured following hyperventilation at 3, 5, 10, 15, and 20 minute intervals to determine if you may have exercise-induced asthma.
There are two reasons that oyur physician may be ordering this test, either to diagnose exercise-induced asthma or to determine if your asthma medications are working properly to prevent exercise-induced asthma.
If the test is to diagnose exercise induced asthma, then there are certain instructions that you must follow before the test for the test to be accurate:
1. No short acting bronchodilators for 8 hours (for example, albuterol, Proventil, Ventolin, Maxair, or Combivent).
2. No long acting bronchodilators for 48 hours (for example, Serevent, Spiriva, Advair, or theophylline).
3. No antihistamines for 48 hours (for example, Zyrtec, Claritin, Allegra, Clarinex, and benadryl).
4. No leukotriene inhibitors for 4 days (for example, Singulair and Accolate).
5. No inhaled steroids for 24 hours (for example, Flovent, Pulmicort, Advair, Aerobid, Qvar, Azmacort, and Vanceril).
6. No caffeine, colas, or chocolate for at least 8 hours.
7. No vigorous exercise on the day of the test.
If the test is to determine if your asthma medications are workign properly to prevent exercise-induced asthma, then you should take all of your regular medications but do avoid vigorous exercise on the day of the test.
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