Home HealthTopics Health Centers Reference Library Research
Join us on Facebook Join us on Facebook Share on Facebook


Expiratory Volumes



I have a home asthma checker. I freq on the first expiration meet a peak from 650 to 800. What is curious is that with the repeated next two attempt they are from 450 to 500. What would cause this?


Peak flow recordings can provide useful information for some people with asthma in terms of helping them monitor their lung function. All people with asthma should have a written action plan for how to deal with asthma flares and action plans that are based on peak flow readings are just as good as plans based on asthma symptoms. Which plan to use depends upon the individual patient and needs to be discussed with the person’s asthma care provider. I can not give you a specific answer to the reason for the various readings you are getting on your home peak flow meter. Often efforts are variable from one to another or it may be an issue with re-setting of or the precision of the meter. In general you would like to have 3 readings that are very similar and use the best of those three as your recorded value. If you consistently get values as described in the question, I would consider visiting with your asthma care provider’s office staff to be certain you are doing the maneuver properly and they can also check the operation of your peak flow meter.

For more information:

Go to the Asthma health topic, where you can:

Response by:

John G Mastronarde, MD John G Mastronarde, MD
Clinical Professor of Pulmonary, Allergy, Critical Care & Sleep
College of Medicine
The Ohio State University