Pulse Oximeters (oxygen saturation fi... - Asthma UK communi...

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Pulse Oximeters (oxygen saturation finger probes)


Hi all,

I hope everyone is well and staying safe😊 .

We wanted to post something about the use of pulse oximeters as these generate lots of discussion on here.

For Asthma: pulse oximeters are NOT currently recommended as part of an asthma care plan (unless specifically directed by an appropriate health professional), this is because they can prevent people from accessing emergency advice by giving a false sense of security. The best way to monitor your asthma is with a Personal Asthma Action Plan (PAAP) asthma.org.uk/advice/manage..., being aware of worsening symptoms, extra use of your reliever inhaler and drops in peak flow readings - these should direct you to get extra support/help from a health professional.

For COVID: Dr Andy Whittamore, clinical lead for Asthma UK and the British Lung Foundation, said, “At this stage, while the use of pulse oximeters in response to COVID is still being examined, it remains really important that before testing at home, people talk to their health care professional. Home use oximeters, which are available for sale online and in chemists, and can be used to measure the levels of oxygen in your blood, can sometimes give poor or inaccurate measurements. It is vital that anyone with questions on using a pulse oximeter at home speaks to a health care professional for advice. Any monitoring done at home needs to be part of a clear management plan and is not a substitute for clinical advice. Anyone worried about their symptoms should speak to a health care professional.”

12 Replies

What is the reason behind the false sense of security oximeters can give asthmatics? Is it that it's possible to be worsening or in a severe attack and still have normal blood oxygen? I'm assuming that's the case, just confirming.

in reply to hilary39

Obviously the experts can confirm but from personal experience that's definitely the case! I have also had some interesting ABGs with relatively low PaO2 while the hospital sats monitor said everything was great (and sometimes the % on ABG is lower than the sats probe too).

It's a shame that the message about good sats but severe attack hasn't always got through to some healthcare professionals. I had an unfortunate situation at a usually good hospital in Feb where I was left for ages struggling because sats were 96% so I must be fine🙄 never mind the lack of ability to talk properly. (Yes they were busy but the triage was really not appropriate, and the sats were all they went on until I finally got to see a sensible nurse!)

in reply to Lysistrata

I feel like we've compared notes about this on other posts, too. I totally agree. And I am always amazed at how few nurses and doctors in urgent care settings seem to know about the basics of asthma.

I typically have a pretty silent chest and don't wheeze even in severe attacks and that alone has led nurses to take me less seriously even if I'm really struggling. A lot of people in this group talk about having a normal(ish) peak flow, normal oxygen, and not wheezing strongly while still having a horrible attack that necessitates steroids and weeks of recovery so it's been really helpful for me to see I'm not alone in that-

in reply to hilary39

Same - I am sad not to be alone in having this issue but at least it makes it easier for me to believe it's not in my head after bad experiences!

Disturbingly the ambulance service in my area still uses wheeze and sats for their guidance re giving nebs/whether or not it's asthma. Some paramedics are sensible and know better (I usually get nebs anyway) but not all, and this really shouldn't be in their official guidance.

I also think some medics (whether paras/nurses/drs) cannot actually tell the difference between normal and 'clear because silent/too quiet'. I have had later/different ones say oh still a bit quiet post-treatment when pre-treatment it was 'all clear no wheeze'. I highly doubt I was more quiet *after* the treatment - that is one of the few times I may actually wheeze!

I could have wrote this word for word!

EmmaF91Community Ambassador
in reply to hilary39

You can have severe or even life threatening attacks whilst your sats are still in an acceptable range. I have a friend who can have CO2 retention high enough to be classed as near fatal but have oximeters (even on the hosp monitor) still saying her sats are in an acceptable range... then she crashes hard (she’s lost count how many times she’s now been intubated). Typically with asthma sats don’t drop until you’re in dire straits, by which time what may have been an ‘easily’ dealt with attack can kill.

I personally have had multiple life threatening attacks (according to BTS guidelines) but it’s rare for my sats to drop below 94 during attacks and the only time they dropped below 90 they very nearly intubated me. As I’m normally 98/99, a drop to 96 usually means I should be seeking help, even tho it’s still in the completely normal range on the NEWS.

As asthmatics are body compensates really well, right up until it really can’t, and waiting that long til you seek help is very dangerous. But many people do not realise this and so think they are fine and don’t need to seek help (despite bad symptoms +/- meds not working +/- low PF), as their sats are still deemed as acceptable, hence they get the false sense of security that they are fine, when they are not!

As Lysistrata said, there are still some medics who don’t know this either, and so may comment ‘sats are fine’ as if that’s a gauge of control for asthma.

Hope this helps explain, and hopefully the experts here can confirm!

in reply to EmmaF91

So interesting and helpful to hear your experience.

I am the same as the others, in fact i have only ever dropped sats once. My last attack i was about to be placed on Non invasive ventilation and sats were 98.. Asthmatics are very good compensators and so oximetres can provide false reassurance. I have even had a normal ABG before however did show compensation.

If only i could remember this mid attack when i don't think i am bad enough 🤦‍♀️

It does seem like false reassurance. It’s a good way to put it. I wish there were more ways for doctors to accurately gauge how bad our attacks are because I have definitely been sent away from the hospital while still feeling wretched and after just one quick neb (but I’m american and our system as you know is particularly cruel / ruthless—I was once finishing a neb in a hospital when they brought to my bed [i kid you not] a bill for $500 and a credit card swiper. And I had good insurance! In the states we have a high copay every time we go to the hospital).

I often am unsure how bad I actually am when my oxygen and peak flow are normal but I feel like I can’t get full breaths.

Hi everyone, I had pneumonia in March and breathing difficulties 10 days later. My doctor was worried about me and among other things sent me an oximeter to check my sats 3 times a day. Every day the doctor rang me to see what they were. They were at 89/90 for 3 days and I was hospitalised for 4 days With oxygen and the nebuliser and steroids. Apparently my blood gases were extremely low as well. I was told to keep the oximeter to check my sats if my asthma got bad again. With doctors not seeing patients at this time, only I had that oximeter I dread to think what would have Happened. I am very glad that I have it. I think everyone who has asthma should have one.

in reply to Eibhlinn

It sounds to me as if the GP was concerned initially about your sats in relation to having the pneumonia rather than your asthma (actually wondering if it could have been covid given the breathing worsening after 10 days...but maybe they ruled that out?)

As the Asthma UK nurses have said in their initial post, they're not really recommended for asthmatics to use routinely to monitor their asthma so doesn't sound ideal that your GP has suggested this as a good management tool - please make sure you don't just go on the sats if your sats are reading as ok! My sats, for example, were largely ok a week ago in A&E and I still went to ITU because my asthma certainly wasn't.


Hi All,

I Hope you all had a great weekend! Glad to see this has generated a bit of chat!

Yes as a few of you have rightly pointed out on here (including EmmaF91 - our new Community Ambassador😀)oxygen saturation is often the last thing to drop in an acute asthma flare so please don't rely on these, and dont be falsely reassured by normal readings…. be guided by your symptoms and response to your medication - follow your asthma plans 👍

On the other side inaccurate/low pulse oximetry readings may occur when any of the following factors are present:

-Excessive patient movement

-Exposure to bright ambient light

-Nail polish/false nails present

-Skin pigmentation

-Cold hands / poor peripheral circulation / Raynaud’s phenomenon

-Certain cardiac arrhythmias

-Severe anaemia

Whilst Pulse oximeters most certainly have an important place in medical care please be very cautious about using them yourselves at home (without specialist medical guidance) and especially for asthma.

Best wishes to you all ☺️

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