peak flow

[NLGA]

what are the actual figures in a peak flow representative of are they just a basic grade with no relevance to anything else

[eleanordigby]

Hi NLGA. I’m not sure I understand what you mean. Peak flow measures the amount of air, in litres, you can blow out of your lungs in one fast breath.

[NLGA in reply to eleanordigby]

yes but what is for example the 600 what does it mean is it just a made up grade or relevant to a actual grade or could it be 6 in a 1-10

[Nerja2012 in reply to NLGA]

Hi NLGA. I do know that your personal Peak flow is measured by weight height etc , I'm a small female so obviously my lungs are small as well. My predicated peak flow for my frame and age is 320, if I have an asthma flaire and I drop to say 240 I know I need help. Usually a course of steriods. Hope this helps x

[NLGA in reply to Nerja2012]

thank you but I’m trying to understand what the 240 in your case represents

[Nerja2012 in reply to NLGA]

As my Peak Flow should be 320 on the Doctors scale for my build, it means that if I can only achieve 240 into the peak flow I am blowing under my expected target so my lungs aren't working to capacity therefor I need medical advice. As another person suggested look online for the peak flow chart. You can work out yourself from the chart by putting in your age, height and weight. If your not able to do this ask your Asthma nurse for advice. Good luck .

[eleanordigby in reply to NLGA]

I see what you mean, but other than knowing it’s measured in litres, I’m afraid I don’t know. Interesting point…

[NLGA in reply to eleanordigby]

I thought that but reading the spirometer test that seems to be around 3 litres so I thought I’d 300 on the peak the same as 3 on the spiro

[Superzob in reply to NLGA]

This may help:

Peak flow by age and height

[NLGA in reply to Superzob]

it’s more what the numbers mean what are they a grade of

[Superzob in reply to NLGA]

They’re not a grade of anything - they are your actual volume of expired air measured in litres per minute (as shown on the vertical axis on the left of the graph). The graph shows the average reading for people of a specific gender, age and height. Anything below 80% of this reading would be considered a potential problem, but there will always be perfectly healthy people outside the normal range (which is actually 80-120% - some people have amazing lungs!).

Hope that helps.

[CallysMum]

Hi, if you look on the interwebby , there are charts, based on your sex, height and age, that give a max and min for a normal reading.

We are all different, but it gives a benchmark. Sadly even healthy lunged folk have a reduced peak flow as they age. I downloaded one and keep it on my laptop for quick reference if I need it. A chart, not an older person 😆

[NLGA in reply to CallysMum]

yes but it’s what the numbers relate to is what I am trying to find out

[alchemilla12 in reply to NLGA]

as several people have already said it is the measure of the volume of air in litres that you are able to expel in a forced expiration. Not sure why you dont seem to understand ?!

[Lysistrata Administrator Community Ambassador in reply to alchemilla12]

I appreciate the replies have been rude and I have addressed that but this could have been phrased more tactfully. Please can you both remember community guidelines and keep things civil: healthunlocked.com/asthmalu...

•Keep your messages civil, tasteful and relevant

•Maintain respect for other people

[CallysMum]

It's the rate of flow of expelled air through your bronchi. So if you imagine a pipe, a wide pipe will allow more air through than a narrow one. It is a way to measure how constricted your airway is.

[NLGA in reply to CallysMum]

yes I’m cool with the use more the grades

[Troilus]

Does this help?

en.wikipedia.org/wiki/Peak_...

[NLGA]

that’s interesting kind of a puzzle as the spirometer is in litres but a different number system

[teddyd]

I only know what my best is and at what level I need to get help.So much information just confuses me. I just keep it simple.

I know what my peak flow and oxygen levels should be and that's enough for my brain .

[NLGA in reply to teddyd]

fair enough

[Lysistrata Administrator Community Ambassador]

HI, as others have said it isn't a grade, it's how much air you can expel in a set time. That value changes depending on your age, sex, and height (you would expect for example a 25 year old man who is 5'11 to be able to blow out much more, and so have a higher best peak flow value, than a 70 year old woman who is 5'2").

However, there are also individual variations, depending on things like whether you're a current or ex smoker, or whether you did a lot of sports when you were younger. The predicted values on the charts are a start, but you need to work out what your own best value is and use that - it might be lower or higher than the charts. I have severe asthma but mine is much higher than predicted, probably because I used to sing and play the oboe as a child.

The important thing is to compare your readings against yourself, never anyone else. That 25 year old man I mentioned might be having an attack and need hospital at the exact same peak flow reading that's really good for the 70 year old woman.

This post might help with more information about peak flow: healthunlocked.com/asthmauk...

[NLGA in reply to Lysistrata]

great info

[TheWelshWriter]

I would say the number must correspond to various volumes but I don't know what those volumes are. This must be available on the Internet though, possibly on a research paper. Good question though!

[NLGA in reply to TheWelshWriter]

could be I will have a search

[Naturesvalley]

I recently asked my respiratory consultant about what my peak flow should be. And he said it should be about 400. Considering I only have 80% lung capacity thanks to covid. I do regular peak flow readings.. I have just had a flare up where my readings went down to 230 and then I contacted my gp who acted quickly and started me on steroids, and antibiotics and also increased my ventolin usage to a regime that we have found that works . Luckily I have an appointment with my consultant in the next couple of days. However my peak flow have started to increase

[NLGA in reply to Naturesvalley]

let’s hope that increase continues

Could I ask how you found out your lung capacity is covid related as I believe that’s what has increased my asthma / breathing issues but I can’t get my GP to think the same

[Naturesvalley in reply to NLGA]

I had covid very badly in 2020. And had pneumonia on top of that. I was in hospital with covid. They did a CT scan an found lesions on my lungs that my respiratory consultant said were due to covid. I was not asthmatic before covid. Covid has caused all my lung problems and it took almost a year for it to stabilize. Luckily I have a excellent gp and good consultant

[NLGA in reply to Naturesvalley]

I had covid that kicked off my issues I believe I ended up with pneumonia and 11 days in hospital over 2 spells within a month of each other , I had a CT which I’m told was normal but I was never breathless walking upstairs for example before covid

[alchemilla12]

***Moderator here: Editing this as rude replies have been removed***

as several people have said it is not about grades....

[Poobah]

It's litres volume expelled per minute. I know we don't exhale for a minute in the test, which is short and sharp, but there has to be a universal baseline measurement as each test exhale can't be the same length of time. The litres measurement was adopted EU wide, I seem to remember a different scale in the UK before that as I had to get a new PF meter.

[NLGA in reply to Poobah]

the spirometer and peak flow have very different numbers do you know what the scale is to compare the two

[Poobah in reply to NLGA]

You may find this article informative. differencebetween.net/scien...

[NLGA in reply to Poobah]

looks excellent info

[Lysistrata Administrator Community Ambassador]

Please can everyone remember community guidelines and keep things civil: healthunlocked.com/asthmalu...

•Keep your messages civil, tasteful and relevant

•Maintain respect for other people