Pulse oximeter doesn’t work at altitude

mandm

mandm

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Hi all, I have a pulse oximeter, I think from Amazon. On the ground it works fine but in the air at altitude, I tested it at 4500’ today, it doesn’t work. It turns on, pretends it is measuring my finger and then it turns off automatically. I’ve done this a few times on different days and it keeps happening.

Anyway, is there a special device to get to use in airplanes or does anyone recommend a certain brand? Welcome to share the Amazon link if it could be bought there. Thanks in advance.
 
I've used the pulse oxy built into my phone at 10k. I don't think the altitude is the issue.
Most likely it's the vibration or hand position, disturbing the blood flow. Most of them want you to be calm and relaxed.

Another possibility (less likely) is that you might be having a carbon monoxide problem. Pulse oxys can't tell the differemce between oxygenated hemoglobyn and hemoglobyn stuck with carbin monoxide (the second one is actually redder than the first), and if things aren't adding up it might just refuse to work.
 
Was it cold or were you cold? I've found mine doesn't work well with cold hands.
 
Sometimes it helps to put it on sideways, not on top of the nail
 
I assume there's some kind of automatic gain control baked in to the devices and it has a hard time "seeing" if your hands are cold and dry; it sometimes seems erratic for me at 10k and I need to try a few fingers before it gets a good reading.
 
A link to the unit you bought would help. I've never had an issue with a cheap finger based pulse-ox working at altitude, I had one I bought when I started flying for something around $15 and it worked fine as long as I used it. I've owned a couple of Garmin watches with wrist-based pulse-ox (D2Delta PX and Marq Aviator) and they both work well, however you do have to sit very still for a while for them to take a reading. The finger based ones are more forgiving.

You may have also gotten a genuine Chineseium POS one that just doesn't work.
 
Hang 4 said:
Was it cold or were you cold? I've found mine doesn't work well with cold hands.
Click to expand...
Yes I was cold, however it worked fine on the ground where I was also cold and post-flight.
 
Ted said:
A link to the unit you bought would help. I've never had an issue with a cheap finger based pulse-ox working at altitude, I had one I bought when I started flying for something around $15 and it worked fine as long as I used it. I've owned a couple of Garmin watches with wrist-based pulse-ox (D2Delta PX and Marq Aviator) and they both work well, however you do have to sit very still for a while for them to take a reading. The finger based ones are more forgiving.

You may have also gotten a genuine Chineseium POS one that just doesn't work.
Click to expand...
Let me open up the computer and have a look. Getting a cup of coffee.
 
Ted said:
A link to the unit you bought would help. I've never had an issue with a cheap finger based pulse-ox working at altitude, I had one I bought when I started flying for something around $15 and it worked fine as long as I used it. I've owned a couple of Garmin watches with wrist-based pulse-ox (D2Delta PX and Marq Aviator) and they both work well, however you do have to sit very still for a while for them to take a reading. The finger based ones are more forgiving.

You may have also gotten a genuine Chineseium POS one that just doesn't work.
Click to expand...
Here she is
 
mandm said:
Here she is
Click to expand...
4500’ is not at altitude, but below ground level in much of the country.

I have a very similar looking one from Amazon that works fine at triple that altitude, but I could see vibration causing an issue.

Got a riding lawnmower handy to verify the failure mode?
 
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I've bought half a dozen over time. Santa Medical devices are cheap and reliable. The one I like best is the SM-110 and is less than $20. The red LED display is really easy to read in brighter sunlight vs some of the dimmer blue displays.

SM-110
 
David Loftus said:
I've bought half a dozen over time. Santa Medical devices are cheap and reliable. The one I like best is the SM-110 and is less than $20. The red LED display is really easy to read in brighter sunlight vs some of the dimmer blue displays.

SM-110
Click to expand...
Ordered, thank you.
 
The one I bought with an LED display was not possible to read on a sunny day, so I got an LCD oximeter.
 
Never heard of one failing with altitude. They read inaccurately with CO poisoning. They fail to read for reasons stated above, movement, low perfusion, ambient lighting, poor placement on finger, and some fake nails or nail polish.

I'm sure the nail polish doesn't apply to you of course.
 
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