Low oxygen SPO2 anyone?

I just checked before going to bed and after during a sleep study, and mine was alternating between 93-95 mostly. 4 years ago (one year after getting sick) it was 98..

 

Tried my pulsox for 10 minutes this morning. O2 level varied between 91 and a brief 95, mostly settling at 92.

Lung tests earlier had shown no problem.
Cardiac team was not unduly concerned.
Two normal ECGs last week.
Still breathless when in pem but possibly slightly improved from its worst otherwise.

Just wondering @Mattie whether your recent surgery has affected your O2 levels.

 

Since the pandemic started many people have bought SpO2 monitors. If you have bought one recently or have one already perhaps you could take the time to update this thread with your readings.

I have severe ME. My SpO2 reading is normally 94-96%. My wife is 99% and children 100%. Right after shower the reading is 97-98% and stays elevated for a little while. That would seem to indicate to me that heat opens up the capillaries and allows better oxygen in the blood but that is just a guess.

 

As far as I am aware they work by detecting how red your blood is - as hemoglobin that's bound to oxygen is red. So basically they are looking for red and inferring from that how well oxygenated your blood is. It is probably a little more complicated than that (e.g. they may only be measuring when they detect a pulse etc.) but that would appear to be the essence of how they work.

So in theory anything that makes you redder will probably show up as a higher reading.

They aren't measuring actual oxygen, just the average normal physiological effects of it.

 

Funnily enough, I monitored mine over a week or so last year, so that I would know what's normal for me if I did get ill. It can be helpful to know this kind of thing if your readings don't tend to be typical.

Just done it again: SpO2 around 93%, so same as last year. If I had coronavirus symptoms and phoned NHS 111, the onscreen prompts would tell them to advise me to call an ambulance if it didn't improve fairly quickly.

 

Good point @Wonko - I will need to get my red blood cells tested to make sure they are in the normal range. Luckily that is one of the most standard tests.

 

Not what i meant.

I meant that anything that makes your skin redder is likely to affect an SpO2 reading - such as a hot shower.

 

Useful article, explaining in relatively simple language how they work and how to correctly use them:

https://www.nursingtimes.net/clinic...imetry-in-measuring-oxygen-status-01-03-2002/

 

Have restarted taking mine recently because of covid. Basically I had in mind, as @Kitty commented, that my usual levels would ring alarm bells.

I bought a new monitor because I had misplaced both of my others. Just taking mine- started at SpO94, then 92, then 93, then 92. Basically mostly the same as 2/3 years ago.

edit: thanks for the article @Simbindi . To be read later.

 

Mine varies from about 93 - 97 these days, averaging about 95. I get very occasional levels of 92 or 98. But I've found it difficult to monitor because it changes so often. In years gone by it would regularly be 98 - 99 when tested by a doctor or in hospital. I only bought my Pulse Ox thing fairly recently because of Covid, and my husband is asthmatic.

I did wonder...

Can anaemia reduce oxygen saturation levels showing up on a Pulse Oximeter?

 

The article discusses this and other causes that can affect readings or where the reading needs to be taken with caution.

 

Uncertain - according to a quick google.

The reason for anemia appears to maybe have an effect, but that aside there would appear to be studies suggesting that it doesn't, that it does (raising reported SpO2) and that it does (lowering SpO2).

So...uncertain.

I copied your question into google and hit enter, and google responded with unintelligible incomprehensible gibberish.

 

I'm adding something to my post above...

I mentioned that my husband is asthmatic. I forgot to say that his asthma is well controlled most of the time and it is quite rare for him to have episodes of being wheezy. After I had used my Pulse Ox meter I asked OH to use it for a minute or two. What surprised me is that his reading stayed almost rock steady at 98, with just one brief blip down to 97 before going back to 98 again.

I was surprised since my own reading is constantly changing. A rhetorical question, but I wonder what causes the difference between us.

Edit : Typo

 

Beware of the accuracy of the standard devices when making comparisons. A Google search suggests Readings within 3% is considered acceptable. Some are manufactured with 5% variability. So effectively pointless when making comparisons between devices. I managed to borrow a calibrated NHS pocket device for the last 10 months. My heart rate was Generally low 67 to 78 at rest when I felt better, but ranged higher 80 to 90 in the same situation next day. Movement with the underlining high rate leads to 105 plus and malaise. Returning to SATS, I wake with 92 which I can easily drop to 91 by breath holding for 3 seconds only. All quickly recovers to 94 with a absolute Maximum peak of 97 once I start moving. In theory I have no underlying health conditions.

 

Yes, I think this is important. When using a consumer-level device to establish what's normal, it's probably only going to be useful if you stick to the same one. If the device later shows readings that are consistently unusual for you, and it's definitely not just down to fading batteries, it's worth taking note of it – but the same doesn't necessarily go for a different monitor.

 

Yes, I can make mine go up the same but it only goes up 1 or 2 points so far.

Regarding accuracy, my experience in electronics was that commercial integrated circuits performed the same as industrial or military grade at room temperature. Only when you add extreme temperature variation and vibration/shock do you see differences probably due to sorting of parts and testing. The other difference is things like FDA approval require factory logging of calibration etc. If you can take your SpO2 on a doctors visit you can compare it with the office one to see if it is reading similar. Another quick test is to test on a family member or friend and if it shows 99/100 vs your lower number it's probably operating okay.

What specifically interests me is if enough ME folks have a lower value most of the time could that be related to disease process and could it be useful in identifying ME subgroups in research studies?

 

I bought one recently and got 93-97 settling around 94. When I say settling I mean it still wanders in the range constantly and my impression is that 94 seems where it reads more often.

I immediately thought that the device was faulty and tried it on my son who came out at 98 consistently and then on my wife who came out at 99 consistently.

I decided to then read the leaflet that came with it and saw that low haemoglobin compromises the accuracy of the read. My haemoglobin is consistently low giving haematocrit of 0.39 (I.e just below reference range). My ferritin and rbc cell size is normal I just have a borderline low rbc count and haemoglobin.

I’ve lost interest in it tbh but I am interested to see what others find. I wonder whether heart rate may be an effect? ..I have a resting heart rate of around 57/58 and numb fingers and toes which can also affect reading if it’s due to peripheral blood flow apparently. I also like others suffer from heart rate variability and atm just getting up off a chair makes my heart rate spike at 105 (unusual for me.. I’m in a relapse) so perhaps it’s a combination of things making it variable?