PEAK FLOW METERS
A peak flow meter is a thermometer for asthma. Your child blows into a peak flow meter and a number (the peak flow) is read on the meter. This number can be used in many ways. It can help show how well your child is breathing and how your child is responding to the medicine. The peak flow can sometimes also let you know when an asthma attack is coming, even before your child has any symptoms. It can also give you an idea of how bad an attack is.
The way to use a peak flow meter is to compare the number your child is able to blow now, against the best number your child can blow. Every child has a best number, and this number is called the “personal best”.
To find out your child’s personal best peak flow number your child will use the peak flow meter every morning and every evening for 2 weeks. His or her asthma symptoms should be under good control during these 2 weeks. The highest number over the 2 weeks is the child’s personal best. You and your clinician together can then make an Asthma Action Plan for your child based on the personal best.
How to use a peak flow meter (see GADGET section)
- Your child should be sitting up straight, or can stand if more comfortable.
- Your child should be awake and cooperative, otherwise reading is unreliable.
- Move indicator (pointer) to bottom (zero) of scale.
- Your child should take as deep a breath as possible (breathe in and fill up lungs all the way)
- Place mouthpiece of peak flow meter in the child’s mouth.
- Blow (‘huff’) out the air as hard and as fast as possible (should not be a puff, pop or spit) into peak flow meter.
- Repeat steps 3-6 two more times and record the highest (not average) of the three numbers.
- Write down the peak flow number on your asthma diary.
Lack of cooperation and effort can greatly change peak flow readings.
You cannot reliably compare peak flows between different meters.
Dropping or jarring meters can affect their performance and reliability.
The asthma action plan is developed by your child’s clinician. The goal is to help you in controlling your child’s asthma. The action plan is divided into 3 zones: green, yellow, and red.
The green zone means your child is doing great. Asthma is under control. The child should continue taking his/her regular controller medicines.
The yellow zone means slow down. Asthma is getting worse. The child should continue taking his/her regular controller medicines, but needs to start taking the reliever medicine(s). You may need to call your clinician.
The red zone means Stop. Asthma is bad. Continue taking the reliever medicine – may need to increase dose. Call your clinician if you haven’t already or call 911. Have the child taken to the closest emergency department.
