Central Airway events and AHI increasing (new APAP user)

First of all: thanks to everyone for this fantastic forum. I'm a new CPAP user, having been diagnosed with OSA and an AHI of 8 about two months ago. I'm geeking out over the data that OSCAR shows me from my ResMed Airsense A10 AutoSet machine, but more importantly, CPAP is already helping me sleep better! I'm a little confused by what I've experienced over the first few nights using my CPAP machine, though, and I'm hoping someone can help me figure out whether to just stay the course or if I should try to adjust my machine's settings.

My doctor prescribed a range of 4-20, and the EPR is set to 2 (full-time). I'm comfortably using a ResMed F30i full-size mask, in case it matters. In the first three days, my experience has been:

• 3/15: AHI 5.70, CA 3.92, OA 1.43, slept comfortably, 99.5% max pressure was 12.78

• 3/16: AH 5.69, CA 4.21, OA 0.87; had tinkered with settings to turn off EPR but woke an hour in very uncomfortable and turned it back on; 99.5% max pressure was 17.08

• 3/17: AHI 8.45, CA 6.30, OA 1.26; woke with unexpectedly high pressure in the early AM but did my best to relax and fell back asleep; 99.5% max pressure was 16.05

I've been surprised at my AHI rising (along with CA) over the last three days, and it seems to me that there's some correlation of high clusters of CA events with elevated pressure levels. I'm also surprised that I was woken by high pressure on the second and third nights, given my first night's experience.

Is it too early for me to draw any conclusions, so I should just stay the course? Or does anyone have suggestions on any adjustments I might try to make?

Screenshots:




Thanks!
Eric

http://www.cpaptalk.com/viewtopic/t1585 ... eview.html

viewtopic/t183806/Attachment-storage-is ... MENTS.html

Please fix your image links.

Sorry, I thought I had the permissions setting right on those images, but I was mistaken. Fixed now!

Are you having any nasal congestion at night when using the machine?

At what altitude do you live?

Taking any medications of any kind? If so, what?

Any chance you were awake at around the 05:00 mark on your report for Friday?

Do you know about SleepHQ?

I have had a little intermittent nasal congestion in my left nostril.

Wikipedia says my city's elevation is 486 ft (148 m).

I'm not taking any medications.

Yes, I was woken for awhile at around 4:40am on Friday night/Saturday early morning.

I don't know anything (yet) about SleepHQ.

eric_sleeps wrote: ↑

Mon Mar 18, 2024 12:12 pm

(snip)
My doctor prescribed a range of 4-20, and the EPR is set to 2 (full-time). I'm comfortably using a ResMed F30i full-size mask, in case it matters.
(snip)

A range of 4-20 is not a 'prescription'... that's the default the machine ships with. I guess this passes for sleep doctoring these days, what with home sleep studies and no lab time.

IMO, if you want to lower your CA's, reduce EPR to 0. Your leaks look OK, that's good. Stay off your back if you can... that's a killer for OSA... and your machine is taking you to the Moon fighting flow limitations and OA's. H's and CA's don't drive your pressure up... those wide pressure fluctuations, combined with the EPR, are probably stripping your CO2... counter-intuitively, you need CO2 to make you breathe... if you don't have enough CO2 your body can get into binge-purge cycles causing CA cascades.

Since your doctor left you on your own to titrate yourself you should probably have an O2 monitor... lots of us use the O2Ring, it's not cheap, but it works well if you can get it to fit right. This also gives a Movement graph, like a hillbilly EEG, letting you know when you rolled over etc. This data can be loaded into Oscar (and SleepHQ). If you decide on another monitor make sure Oscar can read it. Also important to have the clocks synced up, the ring has to be sync'd via the PC app... not sure if BT on the iPhone can sync the clock. Ring doesn't help much if the clocks aren't lined up pretty close.

Pugs mentioned SleepHQ... Uncle Nick has a free trial, I think you should try it... it's like Oscar, but you can actually share a link to one night so that we can zoom in just like Oscar using a browser. Here's one night of my trial, note the big mouth leak at 3:10am, failed tape job!

https://sleephq.com/public/0a2adc38-6ac ... d330799694

So my opinion (not a doctor), lose the EPR for a night... then start narrowing your pressure ranges focusing in on your good therapy range... and stay off your back, your tongue will send pressures sky-high and no amount of CPAP pressure can make it move.

SleepHQ has a free version that you can post a link to the results and then we (and other forum members) can zoom in on those flagged events in the flow rate graph to check your respiration pattern to see if you were awake or asleep when those events got flagged.

The machine can't tell awake breathing from asleep breathing. It only measure flow rate or breaths and often our awake breathing is irregular and the machine thinks that irregularity is some sort of apnea event but if we aren't asleep that flagged irregularity is meaningless because we have to be asleep for it to matter.

I suspect that is what you are seeing with those little clusters of CAs/centrals....awake breathing irregularities getting flagged. Using SleepHQ we can confirm or dispel that idea. If for sure asleep then we have one talk but I bet that the bulk of those CAs/centrals are going to be awake or arousal related and thus they don't mean much except that you weren't asleep.

vandownbytheriver wrote: ↑

Mon Mar 18, 2024 12:59 pm

A range of 4-20 is not a 'prescription'... that's the default the machine ships with. I guess this passes for sleep doctoring these days, what with home sleep studies and no lab time.

Yes, I figured as much. My ENT is attentive overall, but he's not a sleep specialist.

vandownbytheriver wrote: ↑

Mon Mar 18, 2024 12:59 pm

So my opinion (not a doctor), lose the EPR for a night... then start narrowing your pressure ranges focusing in on your good therapy range... and stay off your back, your tongue will send pressures sky-high and no amount of CPAP pressure can make it move.

Thanks for your suggestions. I had disabled EPR on night two (as you may be able to see from the graph) but then re-enabled it when I woke feeling unable to fully exhale an hour later. Staying off my back is tougher for me; I've always been a mostly back-sleeper with a little side-sleeping here and there. I guess my surprise was that things seemed to go really well the first night without the pressure shooting so high, but I guess there are a lot of variables at play... I've had multiple overnight disruptions (family members sick, getting up early, etc.) every night over the last three nights!

vandownbytheriver wrote: ↑

Mon Mar 18, 2024 12:59 pm

So my opinion (not a doctor), lose the EPR for a night.

He's got a little problem trying that idea.

Or had....I think he edited his original text because in it he mentioned turning EPR off but struggled to sleep and breathe (big surprise he had a problem moving air with that minimum of 4 ) but I don't see that mentioned when I looked back to copy/paste that part of his text.

I am betting my last dollar that those CAs/centrals aren't related to pressure or EPR (but need to use SleepHQ to verify) and instead related to being awake.

But on the chance EPR is a factor for causing those centrals turning it off and using minimum of 4 is a recipe for disaster.
How about using a minimum of 6 or 7 and see if more air moving is more conducive to falling asleep without feeling like one is suffocating???

Pugsy wrote: ↑

Mon Mar 18, 2024 1:06 pm

I suspect that is what you are seeing with those little clusters of CAs/centrals....awake breathing irregularities getting flagged. Using SleepHQ we can confirm or dispel that idea. If for sure asleep then we have one talk but I bet that the bulk of those CAs/centrals are going to be awake or arousal related and thus they don't mean much except that you weren't asleep.

This is a helpful suggestion and insight. Given how I've definitely been woken (albeit mostly briefly) multiple times each night over the last three nights, I'm going to wait until I have an uninterrupted night of sleep, and then I'll report back and/or upload to SleepHQ for more help. Thanks so much!

Would it be unwise at this point to lower my max pressure from 20 to something like, say, 13? On the first night, I was able to get a mostly good night's sleep and the max pressure stayed almost entirely below 13. But that's a really small sample size too.

Pugsy wrote: ↑

Mon Mar 18, 2024 1:14 pm

Or had....I think he edited his original text because in it he mentioned turning EPR off but struggled to sleep and breathe (big surprise he had a problem moving air with that minimum of 4 ) but I don't see that mentioned when I looked back to copy/paste that part of his text.

I am betting my last dollar that those CAs/centrals aren't related to pressure or EPR (but need to use SleepHQ to verify) and instead related to being awake.

But on the chance EPR is a factor for causing those centrals turning it off and using minimum of 4 is a recipe for disaster.
How about using a minimum of 6 or 7 and see if more air moving is more conducive to falling asleep without feeling like one is suffocating???

Sorry about the edits, but I think the last version did mention what you said: when I disabled EPR altogether on night two, I woke an hour in struggling to exhale. At that point, though, the graph suggests that the pressure was at just above 12.

Nasal congestion can make the Flow Limitation graph look pretty busy and also trigger your machine pressures to increase trying to kill the FLs because FLs can be an early warning sign the airway is trying to collapse and preventing that collapse is what the machine in auto mode is going to try to do and that's with more pressure.

All fine and dandy but more pressure won't/can't fix nasal congestion that is physically caused by the tissues inside the nose getting congestion. The machine will try like hell but it won't improve FLs that are coming from nasal congestion.
Instead you have to use the other normal methods for trying to open up the nose....meds, sprays, rinses, etc. Whatever works for you.

eric_sleeps wrote: ↑

Mon Mar 18, 2024 1:15 pm

Would it be unwise at this point to lower my max pressure from 20 to something like, say, 13? On the first night, I was able to get a mostly good night's sleep and the max pressure stayed almost entirely below 13. B

If you never, ever reach the maximum pressure setting then it becomes a moot point whatever it gets set at.
The machine only goes where it thinks it needs to go in an effort to PREVENT the airway from collapsing....now sometimes it goes chasing nasal congestion with that more pressure but like I said above ...it won't help if those FLs are from inside the nose itself.

There are actually several experiments that you could do in an effort to figure all this out.

1....work on the nasal congestion
2....reduce max setting to 10
3....increase minimum setting to 5 or 7
4....try turning EPR off or at least reduce it
5....try sleeping with EPR at what is most comfortable

Remember....your primary goal is "get decent, solid sleep"...because without sleep none of this data really amounts to much. Awake/arousal flagged events cloud the data reported and makes it hard to know if what we are seeing is real or not.
When you have time load the Fri report into SleepHQ and lets see just how worrisome those centrals really are or aren't.
If you do need EPR to sleep and it is NOT the trigger for the centrals then I want you to be able to be comfortable and get to and stay asleep so you might as well use EPR if it helps you sleep.
There's a very small chance that EPR is a trigger for your centrals....but and even much bigger chance those centrals are awake/arousal related.

Pugsy wrote: ↑

Mon Mar 18, 2024 1:06 pm

SleepHQ has a free version that you can post a link to the results and then we (and other forum members) can zoom in on those flagged events in the flow rate graph to check your respiration pattern to see if you were awake or asleep when those events got flagged.

Of course, I can zoom in myself too in OSCAR... Any chance that "awake" looks like this:

while "asleep" looks more like this?

eric_sleeps wrote: ↑

Mon Mar 18, 2024 1:40 pm

Any chance that "awake" looks like this:

Every chance.
You weren't sound asleep for any of those flagged centrals.

I don't have a good example of an asleep centrals but pretend these 2 OAs have CA flags instead.



Asleep breathing is very regular and very rhythmic.
Awake/arousal breathing is all over the place.

See below....I circled the asleep breathing in red and anything outside the circled area I wasn't asleep.

and same time frame zoomed out a little more