What's going on with my spO2 dips? ASV.

[icipher]

Hello all, happy holidays.

Last night I was having a few wake-ups a few hours after falling asleep. I decided to throw my pulse oximeter on. I found something of surprise in my readouts from the oximeter. I see that it twice recorded my oxygen going down to 80%, which is something I've never seen before. I would like to get your honest thoughts on whether or not this looks legit or if it looks more like artifact. I notice my pulse spikes at each occurrence. I do not understand how my O2 could get this low while using the ASV and I've never seen it before.

Also, looking at my data from my ASV, my AHI was 2.0 all comprised of hypopnea. I've attached 2 screenshots from my pulse oximeter readout report.

[SGearhart]

I've had a few like what you show. Mine have even dipped to 0. I've traced it down to a sudden movement. It could be just from changing sleeping position.

[palerider]

I would like to get your honest thoughts on whether or not this looks legit or if it looks more like artifact.

it's impossible for your spo2 to drop 15 points in a few seconds and then bounce right back up to the spot it was before the glitch.

[Demerit]

It's artifact. Nothing to worry about.

[icipher]

Thanks for the replies. Basically the same thing I thought with the very sharp, steep decline and rise.

[HoseCrusher]

I am not sure it is an artifact. The time is over a couple of minutes and the drop in O2 is accompanied by a spike in pulse rate. The pulse went from around 50 to around 80 over the same time frame. Also the % artifact is quite low and there are no gray sections indicating a loss of contact.

With all that said it is a rather abrupt change. Keep checking for a few more nights and see if it goes away. If it does then it may not mean anything.

[Sludge]

I am not sure it is an artifact. The time is over a couple of minutes and the drop in O2 is accompanied by a spike in pulse rate.

Which gives additional support to the artifact theory. During artifact, both values will tend to get screwy. If only one was screwy and other was perfectly stable, then you might be thinking hmm.

A more scientific analysis of oximetry values can be made in non-Walmart oximeters, where the pleth wave can be examined for quality, as well as a more precise measurement (i.e., oximetry waveform values 0.1% instead of 1.0%).

[mecheng]

I quite agree with the partially dislodged artifact probability. It is quite common particularly with clip on finger type of oximeter when the curvature of the clip is not a good match to the particular digit chosen. Tape can sometimes help but may also act as a pivot point.

[palerider]

I am not sure it is an artifact. The time is over a couple of minutes

the time is closer to 30 seconds, possibly less, (the tick marks across the bottom are five minute intervals, a 'couple minutes' would be very broad)

plus, you'll note that the device itself didn't flag an event (the bars across the top and bottom) in the data stream there is a flag for "data good", I'd be willing to bet that it's not set there.

[archangle]

I think measurement error/artifact is the most likely explanation. Zoom in closer on one of the spikes if you can, and it will be probably be easier to figure out.

[HoseCrusher]

I am not sure it is an artifact. The time is over a couple of minutes

the time is closer to 30 seconds, possibly less, (the tick marks across the bottom are five minute intervals, a 'couple minutes' would be very broad)

plus, you'll note that the device itself didn't flag an event (the bars across the top and bottom) in the data stream there is a flag for "data good", I'd be willing to bet that it's not set there.

Let's put some context around this...

I put on my pulse oximeter and relaxed until my pulse rate was in the 50's and my O2 was in the upper 90's. I then exhaled and held my breath.

My O2 went from 97 - 88 in 27 seconds during which my pulse went from 53 - 77. When I couldn't hold my breath any longer I took some deep breaths and my O2 went from 88 - 98 in 18 seconds and my pulse went from 77 - 50.

That's a 9 point drop in O2 and a 24 BMP increase in pulse in 27 seconds and the rebound involved a 10 point increase in O2 and a 27 BPM drop in pulse in 18 seconds. The whole event took place over 53 seconds.

After a few minutes relaxing I tried it again. This time I recorded a 8 point drop in O2 along with a 24 BPM increase in pulse in 38 seconds and the rebound had a 9 point increase in O2 along with a 28 point drop in BPM in 15 seconds. This event ran 62 seconds.

The third time was less of a drop in O2. I saw a 6 point drop in O2 and a 18 BPM increase in pulse in 13 seconds and the rebound had a 7 point increase in O2 and a 24 BPM reduction in pulse in 18 seconds. The total event time was 48 seconds.

When you run a test like this with your oximeter what do you see?

[bwexler]

What brand and model of oximeter are you using? Do you have Sleepy head software? It will provide a nicer more adjustable graph integrated with your APAP. If you have one of the CBS oximeters it will also show profusion index which helps to identify artifacts.

[icipher]

What brand and model of oximeter are you using? Do you have Sleepy head software? It will provide a nicer more adjustable graph integrated with your APAP. If you have one of the CBS oximeters it will also show profusion index which helps to identify artifacts.

Hello,

I have the Pulse Oximeter CMS-50D Plus from Cooper medical, if that helps. I do not think it will integrate into Encore.

[bwexler]

It definitely will not integrate with Encore.
You might want to download SleepyHead software, it is free. Compared to Encore it is like going from an old black and white TV to a 50" Hi Def Flat Screen. SH does integrate the Oximeter data and the APAP data.

[Too tall]

If your sleepyhead software showed an OSA event at that time, then it's not an artifact. It's hard to tell with that large scale. It looks like a sudden drop but it could be over a longer period.