I’ve been watching my Oxygen saturation with a $27 pulseox meter. My range has been all over the place. From 97 to 87. If I get a number and take the meter off and put it back on it gives a completely different reading.

I’m going to do it now as I’m writing this post. First number is SpO2, second number is pulse.
96/98
91/93
94/97
87/95
98/55

How am I supposed to trust this thing? I don’t feel any different whether it’s low or high.

When my father and I had COVID we bought one from Walgreens and was told that they are just as accurate as the professional one. God Bless

I bought the same one my doctor's office uses. I don't know accurate it is, but it is repeatable: Zacurate Pro Series 500DL Fingertip Pulse Oximeter (Yeah, Amazon. Sorry. That's where I had to go to get what I wanted.)

They are reasonably accurate

Why do I consistently get seemingly random numbers??

It isnt a consistent measurement.

I give blood every few months for diabetes and they always put one on my finger. I put mine next to it and they get very similar readings.

I had them score in the 80's and the nurse said, take a few deep breaths. and that sucker shot right back up.

They are a good for a quick look. Fingernail polish, fingernail thickness, dehydration, battery power, can all affect its accuracy.

Also, poor circulation, or "cold" fingers will affect it.

Ensure it is all the way, firmly on your finger, same spot each time, should be fairly accurate and consistent.

quote:

Originally posted by mark123:
Why do I consistently get seemingly random numbers??

You're not looking to get a precise number from these (even the expensive ones in the doctor's office), you're looking to get a relative indication.

Movement, change in positioning of the meter on your finger, using a different finger, your circulation, body temperature, and probably numerous other factors can impact the reading.

I bought a couple of different brands last year, they were cheap and didn't work well so I took them back and got refunded. After a little research I bought the Innovo brand from Amazon. It has been working fine and agrees with my doctor's meter. I paid around $30 for it last year.

Even hospital ones are +/- 2-3%. Important to take a few readings on multiple fingers to see what the trend is. Some ppl take the first reading that comes up. And that’s usually fine on a healthy person with no problems. But it’s important to compare it against another.

I too bought the Innovo brand. I checked it next to two different Doctor's meters and it agreed every time.

FYI, I use the pulse oximeter on my Samsung Galaxy using the Samsung Health app. I've never used a iPhone so I'm not sure if they have something similar. I get different reading dependent on whether I'm breathing through my nose or mouth.

quote:

Originally posted by redstone:

I had them score in the 80's and the nurse said, take a few deep breaths. and that sucker shot right back up.

This makes sense. One time I was getting an MRI or something similar but the nurse had to inject me with something. She said I was going to feel a cold sensation.

Within seconds, my whole body was feeling it. I remarked at how fast it was and I didn't expect it to happen that quickly and she said, "that's why people inject themselves with drugs It's the fast reaction of your blood stream."

It actually measures the color of blood, since it's not like blood sugar requiring a sample. Anything that can change that can and will. Light transmittance thru your skin can be altered slightly which will affect the reading.

Just did the left index vs right and got 97/71 vs 95/72. And like, cmon man it's all the same blood, right? Well, first and second indication, one finger colder - less blood circulation - one finger with a 5 stitch scar line had the higher O2, left vs right handed.

It reads the color shift of the little red LED and what gets bounced back, I could see any surface contamination that changes color would be possible to change the O2 reading.

Anyone try their big toe?

Paint your finger with Sharpy and try it, post the results. (No, but its a thought.)

If you get a consistent 87 or below, medical attention is needed Im told. The wife was working with an end of life patient at home and the O2 was a necessity a few times a day in maintaining proper care.

Don't let the Lazyboy eat you and you don't have to check. Two more trees to cut down for landscaping should round out my week. I already hedge trimmed the big grass, I need to split wood Saturday (wood lot sold larger than normal splits from 50" trunks) and State taxes need doing. Thats how you stay in shape when you are retired.

I've found the cheaper meters to be less accurate.

Dad had one for his heart issues. It was one of the more common designs -- spring loaded to clamp on the fingertip, took the reading from your fingernail. They generally cost $15 to $25. I bought one from Walgreens to see the results during my daily bicycle workout. It wouldn't reliably read pulse rates over 120. As I regularly push to a pulse of 150, sometimes 160, that was a problem. Oxygen readings were all over the place, too.

I returned the unit to Walgreens and upgraded to one the reads off the skin of my fingertip. I don't recall the brand, but it cost a little less than $100. Readings seem to be accurate. Pulse rates are indicated in bands of 3 or 4 bpm on my higher end. Meaning that I get 144, 147, 151, 154 bpm, but not rates in between. With pulse rates below 100 bpm, the increments are 1 or 2 bpm

Oxygen rates go in single digits -- 99, 98, 97, etc. I ride in 2-3 minute sprints, then often check pulse & oxygen. 98 and 99 is normal, if I'm riding well. On days that I feel just a bit off, or push a bit too hard, oxygen levels drop to 97 or 96 and I feel it.

I flipped my finger around so that the nail is on the little light instead of my fingerprint.

94/94
95/95
95/96

But that doesn’t mesh with the manual.

As usually happens, take an aggregate of forum member's responses and you can get pretty dialed in on the truth of a matter.

O2 levels vary. Positioning of the meter affects the reading, as well.

Proove this to yourself with a few quick tests.

Pinch the unit tighter on your finger, check the level. Relax the pressure and check it. Slide it up and down, switch it to different fingers, check the readings.

Try this one. Place the unit on your finger, hold your breath and watch the number slowly fall. Take a baseline reading, then take several fast deep breaths, and watch the number climb. Take a baseline reading, then do some quick physical activity, walk quickly around your house or jog in place for a minute, and watch the number increase.

You're getting a real time number, within the error accuracy range of the meter, and that number can change very quickly depending on the O2 levels at that moment.

The trick is consistent placement and pressure of the meter, and sometimes averaging the readings.

Now, the plethysmograph can be off by quite a bit, depending on certain health issues.

quote:

Originally posted by ensigmatic:
I bought the same one my doctor's office uses. I don't know accurate it is, but it is repeatable: Zacurate Pro Series 500DL Fingertip Pulse Oximeter (Yeah, Amazon. Sorry. That's where I had to go to get what I wanted.)

At a checkup a while back I asked the nurse about the device she was using. Her response: "It does okay. I got it on Amazon...."

quote:

Originally posted by ensigmatic:
I bought the same one my doctor's office uses. I don't know accurate it is, but it is repeatable: Zacurate Pro Series 500DL Fingertip Pulse Oximeter (Yeah, Amazon. Sorry. That's where I had to go to get what I wanted.)

I have 2 of those. They're good.

I HAD a Walgreens branded unit when I got Covid and it was showing me at a 94-95%. Turns out that one was defective, my O2 level was actually at 86-87%. So I trashed it when I found out.

Then, due to a weird side effect of Covid, I ended up with a couple more, the RN had me buy the Innovo brand, also available on Amazon.

Screw the money, buy one or 2 more and compare them. Your O2 level can and will fluctuate, but you want a unit or 2 that agree with each other and that they are accurate enough. Try to get by your Doc's office to have them compare theirs against yours.
.

The new Apple Watch 6 and 7 have quite a bit of medical/health monitoring capabilities, exercise to oxygen content.

https://support.apple.com/en-us/HT211027

You can setup the Health app to monitor specific things, and to notify you of the results or abnormalities.

It also has a fall sensor, you've probably seen the ads on TV, you fall, don't respond and it notifies 911

For the money, it's a pretty good deal, and you can tell time...