Morning o2 reading is lower (93-95%) when using CPAP

[Luminosity]

I understand that anything above 90% is considered perfectly normal. My pre-treatment AHI was only around 9 so I don't get major desats.

When I don't use CPAP, my measurement upon waking up is consistently 98. Whereas if I use CPAP, it'll be around 93-96 and then move towards 98 throughout the day. Shouldn't it be the other way around or at least stay the same level?

Part of me wonders whether this might be a pinched nerve thing with the whole tingling fingers/toes sensation.

[klm49]

I wouldn't give it a second thought myself. Wish mine was that good!

[Luminosity]

My o2 was pretty much 93%+ even before I got my CPAP.
Doctor basically was surprised at my AHI considering my BMI is only 20, no history of drinking/smoking and 99% of the time normal o2 level when asleep.

I guess it doesn't seem bad when there are moderate/extreme sleep apnea members here experiencing major desaturations, but it still feels like there should at least be a scientific explanation for this reversed outcome.

[D.H.]

Even if you don’t have symptoms, you are still at risk for the complications of Sleep Apnea. The profile of middle-aged overweight male is a harmful one as many falling outside the profile are unlikely to be diagnosed. This profile is somewhat self-enforcing. That is you fit the profile, you get diagnosed and therefore you reinforce the profile.

Note that an AHI of nine means that you are experiencing an event every 6⅔ minutes (on average). This cannot be good.

The first thing to do is to fill in your profile. Hopefully, your machine is data capable. If it is, then you can download SleepyHead and see what the problem might be.

[D.H.]

Thanks for filling out the profile subsequent to my last posting. Assuming you filled it out correctly, you have a fully data capable machine.

There should be an SD card in that machine, or at leas a slot for one. If you don't have the card, you can pick up a cheap one. Download SleepyHead to your computer or laptop (there is no Android or I-Phone version). IF you don't have a card-reader, you can find a cheap USB card-reader.

[Luminosity]

Yeah, I'll still continue using it due to the potential complications in the future as I grow older.

My current possible theory for the lower saturation is either a) Pinched nerve from mask potentially being too tight at the back of skull. b) My body being more relaxed and not pumping blood/oxygen around as much. There was some interesting discussion on another forum about a CPAP user no longer being able to donate blood since they fell out of the normal levels of blood count.

As for my sleep quality, I think it's getting better. I still feel a little fuzzy when using CPAP but I just assume this is an adjustment. I saw no noticeable difference between using varying pressure (8-15) and CPAP mode so stuck with 8.2cm. My AHI is consistently around 1.8-3ish now (average around 2.4). Been using the machine for around 2-3 months now.

[palerider]

I understand that anything above 90% is considered perfectly normal. My pre-treatment AHI was only around 9 so I don't get major desats.

When I don't use CPAP, my measurement upon waking up is consistently 98. Whereas if I use CPAP, it'll be around 93-96 and then move towards 98 throughout the day. Shouldn't it be the other way around or at least stay the same level?

No, lower O2 when sleeping is perfectly normal, your awake O2 means nothing about when you're sleeping. You need a recording oximeter, and then check what your sats are throughout the night.

A hypothesis to explain your abnormal readings is that when you're using your cpap, you're sleeping ok, in a more relaxed manner, when you aren't using it, you wake up after an apnea event, and some deep recovery breaths.

[Luminosity]

Oh that sounds very plausible.

Thanks, I have the cheap $15-20 oximeter (no recording) but it sounds like I'd probably need to invest in one that is more expensive ($100) for more accurate measurements.

[palerider]

Oh that sounds very plausible.

Thanks, I have the cheap $15-20 oximeter (no recording) but it sounds like I'd probably need to invest in one that is more expensive ($100) for more accurate measurements.

A CMS50D+ (the plus is important) will record a nights worth of data, and can be imported into sleepyhead to correlate with your sleep.