Peak Flow Meters and Logs

Working Together

We spoke to asthma patients and health professionals (such as physicians, nurses, nurse practitioners, physician assistants, pharmacists and health educators) about important messages for managing asthma. This brochure captures some of the ideas they shared, and is intended for patients and health professionals to use together to improve their partnership in managing asthma.

We learned people may have different views about asthma

What Asthma Patients & Parents Said What Doctors & Other Health Professionals Said Ideas for the Patient and the Health Care Team
I've never heard of a peak flow meter. Peak flow meters can be helpful for many patients. Talk about the peak flow meter and how it measures the fastest speed at which a person can blow air out of the lungs. A peak flow score may give information about worsening symptoms, whether medications are working or whether other factors are making asthma symptoms worse.
I don't really know how or when to use a peak flow meter. A peak flow meter is a valuable tool when it is used correctly and regularly. Practice the technique of using a peak flow meter at the doctor's office. It is not hard to learn how to use one (for general instructions, see "How to Use a Peak Flow Meter"). Patients should review and follow the manufacturer's instructions to make sure that they correctly use and care for their meter.
I know I said I would fill out an asthma diary but I keep forgetting. And I don't have a lot of extra time. Is it really useful? Keeping track of peak flow scores, environmental triggers, medicines, symptoms and asthma episodes is a lot to do on a daily basis, but can provide important information. Create an asthma log or diary that works for the patient. Use a printed log form or keep track in a notebook. Create special abbreviations. Think about a practical way to monitor peak flow scores and/or symptoms. See left panel for examples of asthma diaries, logs and peak flow charts.
Why use a peak flow meter if my child is taking her medicine anyway? How would it help me figure out what causes her asthma symptoms? Taking prescribed medication is the most important thing people can do to control their asthma. Peak flow scores also help us get more information about environmental triggers or other factors that make asthma symptoms worse. Discuss how asthma controller medication should be taken regularly, even if asthma symptoms get better or disappear. Use peak flow scores to search for what is different. For example, does the score decrease after contact with a pet? After mowing the grass? After being out in the cold? Were two or three triggers present at the same time?
My doctor did not mention using a peak flow meter or keeping a log, but both the health educator and pharmacist did and said it was a great idea. Should my doctor and I talk about it? When we recommend using a peak flow meter, it is helpful to use it and keep some kind of diary or log for at least a month. It helps patients make connections among symptoms, triggers and medicines. Consider using a peak flow meter and keeping a daily log. It could stop an asthma attack before it happens because a peak flow score may drop before the doctor can hear a change with a stethoscope or the patient notices asthma symptoms.

How to Use a Peak Flow Meter

If blowing into the peak flow meter makes you cough, your asthma is not under control.

  1. Get the peak flow meter, a pen and your diary.
  2. Put the mouthpiece on the meter (if needed).
  3. Take gum or food out of your mouth and set the meter to zero by sliding the marker to the bottom.
  4. Keep your fingers away from the vent holes.
  5. Stand up, take a deep breath, put your mouth over the mouthpiece and BLOW AS HARD AND FAST AS YOU CAN.
  6. Find the number that lines up with the marker. This is your score.
  7. If you can, try two more times. Slide the marker back to zero and repeat Steps 3-7.
  8. Write the highest number in your diary.

Asthma Resources