Peak Flow Meter Use


A peak flow meter is a handheld device that measures how well your lungs are working. It shows how fast you can push air out of your lungs when you exhale. This measurement can be useful for asthma patients. It can help you decide how to treat your asthma symptoms. It can help you recognize when it's time to seek medical advice.

Using the Meter

A peak flow meter is easy to use. There are many different styles, but all have a mouthpiece and a sliding indicator. To use the device, stand up if you are able. Take a deep breath. Put the mouthpiece in your mouth, creating a tight seal with your lips. Blow forcefully into the mouthpiece with a single breath.

Recording Your Results

When you blow, the air you exhale pushes the indicator. The indicator slides along a track and stops at a number. Write down this number. Now repeat this process two more times, remembering to slide the indicator back to the starting position each time before you blow. Record the highest of the three numbers, along with the date and time, in your asthma diary. This number is called your "peak expiratory flow."

Know the Zones

Based on these numbers, your doctor will establish ranges that will let you know when your lungs are working well and when they are not. Typically, the doctor will establish a "green" zone (which shows that your asthma is under control), a "yellow" zone (which indicates that your asthma is flaring up) and a "red" zone (which shows that your asthma is severe).

Controlling Your Asthma

Use your meter daily as instructed by your doctor. When you are only able to reach numbers in the yellow or red zone, you will need to take steps to treat your asthma. Follow your doctor's instructions, and refer to the steps outlined in your asthma action plan.