Drop in SPO2 but Flow Rate seems OK?

Hi,

I wonder if any of you experts could help me understand whats going on in this chart?

I recognize that my AHI is all fine and dandy, but this is an event that I just don't get.

At 3:03:06am my SPO2 drops from 95% to 90% for approximately 30 seconds but, as far as I can tell, I see nothing in the flow rate that would explain why.

I can see that around 30 seconds earlier there were 3 or 4 shallow, mildly obstructed breaths, followed by a bit of a recovery, followed by normal breaths again.

But could something as seemingly trivial as this cause a 5% drop in O2 for 30 seconds, 30 seconds after it resolved?

I guess the timing between the AS10 and the Wellue Ring could be off, but I don't think so.

Thanks in advance for your help.

Paul

I think you'll make yourself crazy looking at every lone discrepancy that happens on a given night when your AHI is otherwise good and (hopefully) you feel fine. Anything could have happened, and you can't chase all of them.

Hi Julie,

Thanks for your reply.

Yes, I guess you are right.

I'm new to all of this and the amount of data you can capture and analyze is pretty intense.

Just trying to educate myself on what matters, and what doesn't.

Thanks again.

Paul

I would be more apt to chalk that drop up to maybe a loss of contact artifact.

It would take a LOT more than a few reduced flow breaths to actually impact the O2 levels in the blood than what yours "maybe" were.

Put your ring on and hold your breath for 15 seconds...watch to see how or if the O2 levels change when there is zero air flow. Give it a couple of minutes because it's not an instant change to go from air flow to blood O2 levels.

Very good point.

I did the experiment you describe and it took around 30 seconds for my O2 to drop just a couple of points after holding breath (after exhale) for 20 seconds.

pbrankin wrote: ↑

Fri Dec 10, 2021 8:02 am

But could something as seemingly trivial as this cause a 5% drop in O2 for 30 seconds, 30 seconds after it resolved?

It takes time for blood to flow out of your lungs, through your heart, and down your arteries.