How to read PEF metres

[Wimble]

How do I read this PEF meter? Thought I would ask the experts. I am a 58-year-old woman who should get a reading of about 400 but I can only manage 320-ish. I have Multiple Sclerosis and want to know if that is still a healthy reading as it is 80% of what it should be. It says 80 to 100% of normal is in the green zone. Is 320 a healthy reading or do I have another problem?

[EmmaF91 Community Ambassador]

Hopefully this will answer any more PF questions; healthunlocked.com/asthmauk...

PF bests are personal, the predicted is just an average in the population. If you are asymptomatic of asthma issues when you are doing your PF then your probably at or near your best. Best peak flow doesn’t actually mean very much on its own. My best is 143% predicted and I have severe asthma. I have a friend whose best is 68% her predicted and she has no health issues at all. Many things can affect your best score including technique and ‘muscle strength’ of your resp muscles (this is why people may find exercise increases their best score cause the muscles get stronger)

If you’re symptomatic then taking your reliever usually increases your PF and that’s the best score you use.

Hope this (and above post) helps explain things 😅

[Wimble in reply to EmmaF91]

Is “best peak flow“ what you should be on the chart for your age and height? That’s the bit I don’t understand.

[EmmaF91 Community Ambassador in reply to Wimble]

Nope. Your best is literally the best you personally have hit in the prev 6 (12?) months. If your 320 is after medication and you have no respiratory symptoms then 320 is your best.

The predicted is only used for people who don’t know their best to work out their control level until they do know their best.

So for me my predicted is 440 but my best is 630. When I work out my boundaries I use my best. If I used my predicted and I scored 220 I would be at 50% so only just a severe attack, but if I use my best I’m at 34% which is basically a life threatening attack (33%).

PF is measuring your airway narrowness but relies on max lung capacity to give a score: smaller lungs will contain less air so blow out a lower number and vice versa for larger lungs. So if for simplicity’s sake your lungs hold 1L of air at max, you well never hit 1.5L even if that’s what it’s predicted.

Hopefully this (and the link) explains it 😅

[Wimble in reply to EmmaF91]

Thank you. Oh dear it’s not good news for me then is it. I have the lungs of an 80-year-old at 58. Your explanation was very clear but not what I wanted to hear!

[Tugun in reply to EmmaF91]

Many Thanks for the excellent information you have set out in your link. Clear and educational - would be good in pamphlet form!

[Triobolium]

My best is 250, I am 63. I have a reduced lung function because of bad asthma as a child that was poorly controlled (diagnosed in 1960).

[Yetti1]

Not to worry Wimble ... EmmaF91's explanation is very sound - I'll give another example - I am an ex-ICU nurse of ... many years, now 69, active, and a SCUBA diver of 15 years. I had a minor hernia op several years ago, went to the pre-op, and had a PFE - recorded 350, and nurse there commented that she was surprised and expected much more of me, since over 6 feet tall, in good health and exercise. No, that was it, so I accepted that that probably was my level, my norm - not short of breath, exercising no problems. We are all different, and the text-book levels are points in a range of what is 'normal' that may vary wildly.

So, maybe 320'ish is your normal, but I would take a series of readings - after all a Mini Wright meter is less than £10, seems a good investment, which I am thinking of buying myself - certainly good enough to keep an eye on things - you are right to want to monitor your levels, but if you feel fine and healthy, then by all means do some exercises within your tolerances [including breathing exercises] but equally do not feel anxious.

Very Best Wishes - Ross

[Wimble in reply to Yetti1]

Thank you for that and thank you to everybody who has replied. This bloody virus has made us all more conscious of our health situation and I think it is just hard for me to come to terms with the fact that MS has meant I am not a fit healthy woman anymore. Sometimes ignorance is bliss!

[Birthday60]

The graph - which you can google - is just a target for all people dependant on gender, height and age. When I was younger my target was c450 and I varied between 240 and a top score of 360. I am now 62 years old, have semi retired from a very demanding role and am regularly recording 400!!! I am always much better after my annual Xc ski trip to Norway and this year managed to get a second trip in just before lockdown. I think it helpful to graph your readings and record what has been happening when you have a dip - I discovered a problem with Chinese food this way and my business trips to London.... its important to keep cardio fit so pushing yourself walking uphill is good - I took up Nordic walking...to be honest this lockdown has been great for my health as I have been forced to exercise daily and have a good PF record to prove it!!

[Wimble]

I wish! Unfortunately walking with primary progressive MS is not an option.