If you’ve been diagnosed with asthma there’s a good chance you’ve done a Peak Flow either in your doctor’s office or in the hospital. A peak flow measurement is an indication of how fast you can exhale in a very short amount of time. It’s the asthmatics equivalent of a glucometer used by diabetics to check their blood sugar.
If you have moderate to severe asthma your doctor may have prescribed one for you to use at home. Some hospitals use a disposable peak flow meter and you may be able to take those home with you. No matter how you got it you should use it. You don’t need to measure your peak flow every day but it’s a good tool to use if you start feeling tight or having other indications that your asthma is starting to act up.
When you first receive your peak flow meter you should use it at least twice a day for a couple of weeks when you’re feeling symptom free to get an idea of what your “personal best” is. Your personal best is the average of what you achieve when you’re symptom free. There are charts available that tell you what someone your age, height and sex should be able to do. These are predicted normal values. The problem with the predicted values is that they are for people with normal healthy lungs. You might never be able to achieve the predicted value. I’m a female, 5’2” and my predicted is around 430. I do have asthma and my personal best is around 350. If I went to the emergency room and they measured my peak flow and I hit 320 they’d say that was 74% of my predicted and I was in the yellow zone, meaning caution, my airways are narrowing. If they knew my personal best was 350 then 320 would be 91% and I’d be in the green zone meaning everything was normal. For this reason it’s good to know your personal best and let the emergency room staff know what it is when you have to do a peak flow.
Knowing your peak flow is also good when you’re starting to feel tight or wheezy. If you call the doctor when you have the flu one of the things he’ll ask is “do you have a fever?” You tell him your temperature and he knows a little bit more about what’s going on. If you call the doctor because you’re having trouble breathing and you can tell him what your peak flow is, he has a better idea of what’s happening inside your lungs. He may prescribe extra doses of your inhaler or nebulizer. He may prescribe steroids or he may tell you to get to his office or the emergency room.
Some doctors may work with you to develop an Asthma Care Plan for you to follow at home. They may give you guidelines to follow if your peak flow falls into the different zones.
How to use a Peak Flow Meter (video)
If you have moderate to severe asthma your doctor may have prescribed one for you to use at home. Some hospitals use a disposable peak flow meter and you may be able to take those home with you. No matter how you got it you should use it. You don’t need to measure your peak flow every day but it’s a good tool to use if you start feeling tight or having other indications that your asthma is starting to act up.
When you first receive your peak flow meter you should use it at least twice a day for a couple of weeks when you’re feeling symptom free to get an idea of what your “personal best” is. Your personal best is the average of what you achieve when you’re symptom free. There are charts available that tell you what someone your age, height and sex should be able to do. These are predicted normal values. The problem with the predicted values is that they are for people with normal healthy lungs. You might never be able to achieve the predicted value. I’m a female, 5’2” and my predicted is around 430. I do have asthma and my personal best is around 350. If I went to the emergency room and they measured my peak flow and I hit 320 they’d say that was 74% of my predicted and I was in the yellow zone, meaning caution, my airways are narrowing. If they knew my personal best was 350 then 320 would be 91% and I’d be in the green zone meaning everything was normal. For this reason it’s good to know your personal best and let the emergency room staff know what it is when you have to do a peak flow.
Knowing your peak flow is also good when you’re starting to feel tight or wheezy. If you call the doctor when you have the flu one of the things he’ll ask is “do you have a fever?” You tell him your temperature and he knows a little bit more about what’s going on. If you call the doctor because you’re having trouble breathing and you can tell him what your peak flow is, he has a better idea of what’s happening inside your lungs. He may prescribe extra doses of your inhaler or nebulizer. He may prescribe steroids or he may tell you to get to his office or the emergency room.
Some doctors may work with you to develop an Asthma Care Plan for you to follow at home. They may give you guidelines to follow if your peak flow falls into the different zones.
- 80-100% is the Green Zone. Everything is normal, you’re asthma is under control
- 50-80% is the Yellow Zone. Your doctor may have given you instructions to use a different medication or add extra doses of your inhaler or nebulizer
- Less than 50% is the Red Zone. This is serious. You need to call your doctor or get to the emergency room right away
How to use a Peak Flow Meter (video)
- Stand up or sit up straight.
- Slide indicator to zero or the base of the meter.
- Take in deep breath.
- Put the mouthpiece in your mouth and seal your lips tightly around it.
- Blow out as hard and fast as you can (I tell patients to pretend they’re blowing a candle out across the room)
- Remove the mouthpiece from your mouth and write down or remember the reading
- Slide the indicator back to zero and repeat the above 2 more times
- Take the best of the 3 numbers
- Record this number in your peak flow journal/diary
2 comments:
I use to hear the name Peak Flow meter many times but had no idea what its like and what it does, neither i tried to find. But i happened to read your post and found it really informative..Thanks :-)Loved the video
Thanks for sharing detailed information about Flow Meter. Thumbs Up.