Using a Peak Flow Meter
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When you have an asthma flare-up, the airways in your lungs begin to narrow By measuring how well air moves out of your lungs when you breathe out, a peak flow meter may tell you your airways are beginning to get narrow hours-or even days-before you have any symptoms. Your doctor may tell you to take your medicine then, before symptoms appear. This may stop the episode quickly and prevent severe symptoms. Your peak flow meter can also help you and your doctor:
- Learn what makes your asthma worse
- Decide if your treatment plan is working well
- Decide when to add or stop medicine
- Decide when you need to go for emergency care.
How to use your peak flow meter Every time you use the meter, follow these steps:
- Move the indicator to the bottom of the numbered scale
- Stand up
- Take a deep breath, filling your lungs completely
- Place the mouthpiece in your mouth and close your lips around it. Don't put your tongue in the hole.
- Blow out as hard and fast as you can in a single blow.
Do this three times, and write down the highest of the three numbers you get. If you cough or make a mistake, don't count that try. Use the meter again to get an accurate reading.
Your personal best number
Each person's asthma is different, and so is each person's personal best peak flow rate. Your treatment plan is for you only, and that's why it's based on your own personal best number. To find your personal best number, take peak flow readings at least once a day for two to three weeks while your asthma is under good control-when you feel good and don't have any asthma symptoms. Your personal best is the highest PFR you obtain consistently during the testing period.
Follow the traffic signals once you know your personal best peak flow number, your doctor can show you how to divide your meter into zones that are set up like a traffic light:
- Green zone (80% or more of your personal best number) means your asthma is in good control. Take your long-term control medicine and follow your usual routine.
- Yellow zone (between 50% and 80% of your personal best) signals caution. Use your quick relief inhaler right away. Also, your asthma may not be under good day-to-day control. Call your doctor and ask if you need to change or increase your daily medications. Think about whether you've been exposed to anything that triggers your asthma (cigarette smoke, cold air, or a pet cat, for example), and what you can do to avoid triggers.
- Red zone (50% or less of your personal best Flullnber) signals a medical alert. You niust use your quick relief inhaler right away. Then call your doctor or emergency room and ask what to do, or go directly to the emergency room.
Source: Adapted from National Asthma Education Program Expect Panel Report It: Guidelines for the Diagnosis and Management of Asthma. Bethesda, MD, US Dept of Health and Human Services Publication No. 97-4051, 1997
Revised February 9th, 2006 |
