Peak Flow Meter
What it is
A peak flow meter is a device that measures how quickly air can move out of the lungs. During an asthma episode the lungs begin to narrow making it increasingly hard to move air out of the lungs during breathing.
How it can help you and your doctor
- Catch early airway narrowing hours or even days before symptoms occur (by giving your child medicine early, you may be able to prevent a serious asthma episode)
- Learn what makes your asthma worse
- Decide if your medicine plan is working well
- Decide when to obtain emergency care
How to use
- Place indicator at zero
- Stand up and take a deep breath
- Put the meter in your mouth closing your lips tightly around the mouthpiece (do not put your tongue inside the hole)
- Blow out as hard and as fast as you can
- Write down this number
- Repeat steps 1-5 two more times. Write down the highest number in your peak flow diary.
Peak Flow Zone System
Finding Your Personal Best
Your personal best peak flow number is the highest peak flow number can achieve when your asthma is under good control. Good control is when you feel good and do not have any asthma symptoms.
To find your personal best take peak flow readings:
- At least twice a day for 2 to 3 weeks
- When you wake up and between noon & 2:00 pm
- Before and after you take your medicine for quick relief
Green Zone - Good Control
No asthma symptoms are present. Take your medicines as usual
Yellow Zone - Caution
Your airways are becoming swollen and narrowed. Follow your asthma action plan to try to prevent a serious asthma episode. Also, your asthma may not be under good day-to-day control. Call our office if you are not back in the green zone within 24 hours.
Red Zone - Medical Alert
You are having an asthma episode. Follow your asthma action plan. If you do not return to your yellow or green zone within 30 minutes go to the closest emergency room. If, however, you are having signs or severe difficulty breathing go to the nearest emergency room immediately or call 911 or an ambulance.