Apnea testing

[theMezz]

Can someone get an idea if he had sleep apnea by only looking at the blood oxygen level while sleeping, and why or why not. 

I already had full sleep study, I’m asking for someone else who is using blood oxygen level device nightly. 

Thanks for your time.

[greatunclebill]

Low blood o2 level is one sign of possible apnea, but not the only one. low blood o2 levels can come from other things.

[SevereApnea]

Hi theMezz

Good question.

Short answer: No.

I think everyone here would agree you need a PSG to see if you have Respiratory Sleep Disturbance  ("apnea"), which type, how bad, the consequences of, etc.
 
Long winded answer: (sorry I do get carried away  )

If you have some way of measuring your O2 while you are asleep....

1. and your O2 never drops, this does not mean you don't have Respiratory Sleep Disturbance  ("apnea")**

 2. If O2 does drop while sleeping, this does not mean it is due to Respiratory Sleep Disturbance ("apnea"): you may have had a heart condition, lung condition, embolism, CNS condition, choked on your dentures, survived a pillow attack, whatever...

My Question: so what did your sleep study show?

---

**
When I first got my oximeter, I tested my pO2 while awake while breath holding.
30 secs breath hold: no change.
60 secs breath hold: no change.

Sequential 30 secs breath holds with 15 secs breathing in between, minimal fluctuation between 94 - 97%, until I eventually had to stop.

Even with sequential expiratory breath holds my O2 hardly dropped, until I had to stop (CO2 drives the urge to breath, not O2).

Caveat: I have no lung or CVS conditions, and my results may differ one day when I do, as may yours.

In my year on PAP therapy even with Oximeter on most nights, I hardly ever drop below 91% even with Apneas of up to 40 seconds or more. See attached for one night when I did: note the low (inadequate) pressures and low (inadequate) EPR. Note that this was even wearing a SCC (neck collar). Even partial PAP therapy can reduce our apneas, both the number of events, duration of events and clustering of events.

My conclusion is that, for me, repeated episodes of sleep apneas, of long or moderate duration, one after the other would be needed to induce low pO2 and indeed that is what my sleep study showed. 

Hence chin tucking and clusters of apneas, as often described in this forum, are to be avoided.

[attachment=28658]

[Mogy]

I believe that a pulse oximeter to be fairly accurate to determine if you have OSA. It is not perfect, but it is fairly good.
A link to a study looking at the issue: (there are a lot more)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3927434/

[staceyburke]

No it does not. I use O2 24/7. My O2 level is low when my apnea is controlled. There are to many things OTHER than sleep apnea that could cause it.

[sheepless]

thanks for the great post SevereApnea. informative about a subject I know nothing about.

[Shadowpup]

SevereApnea,
Great post.  Hope you are on the road to recovery.  Best wishes.

[Mogy]

I believe that a pulse oximeter to be fairly accurate to determine if you have OSA. It is not perfect, but it is fairly good.
A link to a study looking at the issue: (there are a lot more)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3927434/

I should have added that knowledge concerning interpretation is quite important. You need some experience with the output to make good judgements.

[SevereApnea]

Thanks sheepless and Shadowpup, yes I believe I am, thanks to this forum!

Mogy, thanks for the reference.

Briefly reading the article, my observations are:

1. this is proprietary software combining oxygen desaturation with other data (I presume similar to what you get in smart watches) and not on O2 levels alone. 
2. They somehow compute/predict AHI from this...
3. ... based on selected desaturation levels of 3% or 4% which yield different statistical results.
4. Pre-test bias because this is already a cohort who are suspected of RSD.

Implications for screening?
Implications for marketing?
Implications for business opportunities in the Covid-19 area and stretched health resources?
I leave you to decide.

Take home message: their predicted AHI are not based on Oxygen desaturation alone, which answers the original question in the first post.