AirSense 11 settings to tweak to reduce central apneas?

[jsam]

I definitely feel worse the next day on nights like this. One thing I noticed is my Apple Watch showed SpO2 dropping to 92 last night (between 2am-3am) while on the other more normal nights it’s always been 96-100. I know Apple Watch O2 data isn’t considered to be very reliable, so maybe I should invest in another tracker. Is there a device (either just O2 or other sleep tracking as well) that this community views as the best choice? I see several on the wiki but it’s not clear to me if there is any consensus on the best (including most compatibility with OSCAR).

Otherwise, I’ll try experimenting with min pressure increase and report back.

[Dormeo]

On the home page for Oscar, you’ll see an option for Oximetry Wizard. There you’ll find a list of oximeters compatible with Oscar.

But O2 at 92 is unremarkable, so I’m not sure an oximeter is a good investment. Still, if it would help your peace of mind, go for it.

[Jeff8356]

... I see several on the wiki but it’s not clear to me if there is any consensus on the best (including most compatibility with OSCAR). ...

That would depend on what OS you have. The Wellue/Viatom brand has Windows/Mac/Smartphone apps. They require you to use their software to get the data off the device first, then import that file into OSCAR. The most popular models seem to be the Ring and SleepU.

For Contec it's Windows only. You also have to use their software to get the data from the device first, then import into OSCAR.

Wellue seems to be the more favored brand. It's smaller and more convenient than the Contec.

I have both the Wellue SleepU and the Contec CMS50F. The bottom line is they both get the job done and are both compatible with OSCAR.

[jsam]

Thanks for the suggestions on O2/pulse trackers. I got a SleepU and tracked my first night of sleep. It looks like there is a pattern of heart rate spikes and small dips in O2 right before the apnea events. Perhaps this is just what you would expect? Is this typical and/or does it suggest any further avenues of inquiry?
Zoom:
   
Full night:
   

[Dormeo]

I suspect that the two devices aren't perfectly synched up, and that the O2 drops + heart-rate spikes actually follow the events.

A fair number of CAs may be happening when you've been aroused from sleep (or aroused from a deeper sleep to a shallower sleep). Did your sleep study say anything about arousals? I continue to think the real problem for you is arousals rather than the CAs themselves. It's the frequent arousals that can leave you feeling unrested the next day.

Unfortunately it can be tough figuring out what is causing arousals. That's why I ask about your sleep study, in case it included any pertinent information, e.g., about RERAs (respiratory effort related arousals), leg movements, or an arousal index.

You could consider removing one additional potential source of arousals by setting your minimum pressure equal to your maximum. If you want to go this route, start with 8. Stick with that for a few days, then you might want to see what happens if you inch down to 7.8, 7.6, etc. Lower pressures could leave you with more OAs and fewer CAs, so it would be a balancing act. But again, I think the emphasis should be on getting you some less disrupted sleep, rather than on looking for a particular AHI.

[Crimson Nape]

Oximeter results and flow rates will never truly match.  For one, the flow patterns are recorded at the moment they occur.  Whereas, the oximeter reading is being sensed from one of the most extreme locations for the origin point of occurrence and is only recorded every 2 seconds for most devices.  Additionally, for an SpO₂ to record a variation requires the blood to go from the point of oxygenation and travel to the point of the body where the sensor is located.  This is time dependent on the body's volume pumping efficiency and pulse rate.  The bottom line is, any change is not going to be reported until some time after the fact.

- Red

[jsam]

Yes, sleep study showed what I think is a lot of arousals. Data below. Mostly not leg movements. RERA index was 0. I'll try tweaking the pressure per your recommendation -- anything else jump out from these data?
   

[Dormeo]

Gosh, nothing jumps out at me, unfortunately, except that you would do well to stay off your back if you can. I hope some other forum member can tease more out than I can.

[jsam]

Observations from setting both min and max to 8.0:

- Felt like a rougher night, more awakenings throughout night, harder to get up in morning
- CAs apparently unaffected (28, within the range I've been getting recently)
- OAs very low - only 2 for the whole night, plus 1 hypopnea

Noticing some large rapid heart rate changes - below from around 45 to 95 in a few minutes, along with some irregular breathing patterns. I don't know if there is a way to nail down cause and effect -- or whether they could just be random/unrelated.

   

[Dormeo]

REM sleep can involve an elevated respiration rate; I don't know about heart rate, but I wouldn't be surprised.

I'm sorry using a steady pressure didn't give you some relief from arousals. Because sleep can be so variable from one night to the next, it would make sense to continue the experiment for a few more nights. But I would completely understand if you decided not to.