It's easy to tell that a kid has asthma when he or she is
having a
flare-up
. He or she will have trouble breathing and may wheeze and cough.
Other times, though, the kid may seem to breathe without any
trouble.
But asthma is tricky. Sometimes an asthma flare-up may be
brewing, but the kid just doesn't know it yet. That's why a
peak flow meter is a handy tool.
A peak flow meter is a device that measures how well a
person's lungs are working. A person blows into it and the peak
flow meter measures how much air the lungs pushed out. If someone
with asthma can't blow out as much air as usual, this may mean
he or she is going to have an asthma flare-up.
Using a peak flow meter is simple. Set it to zero. Then stand
up, take a deep breath and then blow as quickly and strongly into
it as you can. It's kind of like blowing into a balloon.
The meter has numbers on it - kind of like a ruler. When you
blow into the meter, a little marker slides up the meter to show
how much air you were able to get out. An adult can help you by
writing down the number the marker points to. This is your
"peak flow." To get a good reading, you'll need to do
this three times.
Depending on what your peak flow reading is, you'll know if
you're breathing fine, if you're going to have an asthma
flare-up, or if you need to get help right away. The numbers on the
meter are in different color zones. The zones are green, yellow,
and red, just like a traffic signal.
The color zones are a way of letting you know how you're
doing. For instance, a reading in the green zone means you're
breathing is OK. Readings in the yellow and red zones require
action, so talk with your doctor about how to handle readings in
those color zones.
Not all kids with asthma need to use a peak flow meter every
day. Your doctor will tell you when you need to use one. But if you
take asthma medicine every day, you may need to use your peak flow
meter once or twice a day. These readings also can help your doctor
figure out if your medicine is working the way it should.
It's important to use your peak flow meter as often as your
doctor asks you to and to talk about the numbers at your
appointments. By collecting this information and sharing it with
your doctor, you're helping him or her provide the best
treatment for you. Remember, you and your doctor are on the same
team - the one that wants you to breathe easier!
Reviewed by:
Elana Pearl Ben-Joseph, MD
Date reviewed: May 2007
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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