How you prepare
By Mayo Clinic staffWork with your doctor to make sure you get the right type of peak flow meter. Peak flow meters are available over-the-counter and can be purchased at a pharmacy. There are several types of peak flow meters available, and all of them work basically the same way: You blow a fast, hard breath into a mouthpiece and record the resulting score. However, there are a few differences.
- Meters designed for young children have a lower scale than do those used for older children, teens and adults. Some peak flow meters can be adjusted to work for either a young child or an older child, teen or adult.
- Basic peak flow meters are inexpensive, simple to use and give accurate readings that you must record in a peak flow diary.
- More expensive electronic peak flow meters record and track peak flow readings automatically.
Using your peak flow meter
Here's the correct way to use a peak flow meter:
- Move the marker to the bottom of the numbered scale, and connect the mouthpiece to the peak flow meter (if it isn't already connected).
- Stand up.
- Take a deep breath, filling your lungs completely.
- Place your lips tightly around the mouthpiece. Blow as hard and as fast as you can with a single breath.
- Note the final position of the marker. This is your peak flow rate.
- Blow into the peak flow meter two more times. Record the highest reading of the three.
To get accurate readings, make sure you know how to use your peak flow meter properly. Ask your doctor or other health care provider to watch you demonstrate how you use it. It's also important to keep your peak flow meter clean. Follow the manufacturer's instructions — most peak flow meters require weekly cleaning with warm water and a mild detergent.
- Measuring your peak flow rate. American Lung Association. http://www.lungusa.org/lung-disease/asthma/living-with-asthma/take-control-of-your-asthma/measuring-your-peak-flow-rate.html. Accessed Dec. 17, 2009.
- Expert panel report 3 (EPR-3): Guidelines for the diagnosis and management of asthma. Bethesda, Md.: National Institutes of Health. http://www.nhlbi.nih.gov/guidelines/asthma/06_sec3_comp3.pdf. Accessed Dec. 8, 2009.
- Tips to remember: Peak flow meter. American Academy of Allergy Asthma & Immunology. http://www.aaaai.org/patients/publicedmat/tips/whatispeakflowmeter.stm. Accessed Dec 8, 2009.

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