Central Apnea induced by CPAP therapy?

[tomkatt]

I was diagnosed in 2017 with Obstructive Sleep Apnea. Since I've been on CPAP therapy I've noticed a high number of central apneas that were not apparent when I was diagnosed. I assumed it's a side affect of the CPAP therapy or just a bad reading on the machine. But lately the number of centrals (or rather, Clear Airway, Dreamstation) apneas is increasing and it's a bit worrisome. And it's bringing my overall AHI up way higher than my liking (like between 7 and 12 lately, when normally I'd be between 3 and 6 AHI)

Does anyone have tips for dealing with this, or any way to address the Clear Airway / Central apnea numbers? It's a bit concerning that at times I'm temporarily not breathing not due to an obstruction but simply because... I dunno, my body forgot or something. Looking at the chart in OSCAR, there's usually quite a bit of sleep/wake junk at the beginning of my sleep period (like the first hour, I tend to have trouble falling asleep), but even if I disregard that window, the AHI is still above 5 overall many nights.

I'm currently uninsured, and with COVID-19 going around, I wouldn't be comfortable doing a new sleep study in any case. I've been mostly managing this on my own over the years, since the DME and sleep doctor I worked with previously pretty much just set the machine to 4-20 and buggered off without being of much help. I've dialed in my own settings over the years, and 9-14 seems to work best for me, though I've been raising and lowering the pressures intermittently the last few weeks to try and troubleshoot this.

[LSAT]

How about filling in your machine and mask in your profile...Then download Oscar and show us a couple charts of you average night.
How long has this increase in Centrals been showing up? Unless your AHI is 7-10 with mostly Centrals, I doubt that what you are seeing are real Centrals.
If you post some charts we will be able to see for sure,

[tomkatt]

How about filling in your machine and mask in your profile...Then download Oscar and show us a couple charts of you average night.
How long has this increase in Centrals been showing up? Unless your AHI is 7-10 with mostly Centrals, I doubt that what you are seeing are real Centrals.
If you post some charts we will be able to see for sure,

Well crap, I thought the machine info was on my profile. Philips Respironics Dreamstation. I'm generally on a Dreamwear Nasal Cushion, but for the past week have been alternating between that and a F & P Brevida. On average my therapy is at 9-14, but for a while now I've been experimenting with pressures off and on to try and address the issue.

For Oscar, what data do you need, and dating back how far? Will the CSV export work or do you need screenshots? My numbers have been a bit elevated, kind of up and down since the beginning of the year, but if I had to specify when this started heavily, I'd say I started having more bad days than good on my CPAP around mid to late April. Would it help to screen shot one of my "good" therapy days and some recent ones to compare against?

Thanks!

[Julie]

DL Oscar free from the 1-2 stickies at the top of the main page - follow instructions re formatting and posting as well as possible (and lose the calendar plse) so we get the best picture of what's what and will advise if any tweaking is needed.

[tomkatt]

Okay, I wasn't sure exactly what to include, so I've added a couple of recent bad nights that are about par for the course (around 12-14 AHI, I seem to be ranging anywhere from 7 to 20, but the really high nights involve waking up and disconnects). I've linked a few bad nights below, the last time I was within "good" margins, and the lowest AHI I've had this year. If you need more info or zoomed in detail on any of these let me know. Pressures aren't all identical, as I've been tweaking around with them a bit since April, so if you need older data from when I had bad AHI at my standard 9-14 pressure, let me know.


Bad nights:





Last time I was under 5 AHI:



Best night this year:

[Pugsy]

Any new medications? Change in dosage of old medications?

The nights that are really ugly.....did you sleep soundly or have trouble falling asleep or staying asleep?
Spend much time with the mask and machine on?

I think I posted this link in your other forum post thread.
http://freecpapadvice.com/sleepyhead-free-software
First thing to do is figure out if you were really asleep or not when the ugly got flagged. If you weren't asleep....they don't count except for make us worry about why such poor sleep.

For now....turn Flex off and see what happens. I know it's weird but sometimes the bilevel situation that using exhale relief creates can trigger central apneas in some people.

[tomkatt]

Any new medications? Change in dosage of old medications?

The nights that are really ugly.....did you sleep soundly or have trouble falling asleep or staying asleep?
Spend much time with the mask and machine on?

I think I posted this link in your other forum post thread.
http://freecpapadvice.com/sleepyhead-free-software
First thing to do is figure out if you were really asleep or not when the ugly got flagged. If you weren't asleep....they don't count except for make us worry about why such poor sleep.

For now....turn Flex off and see what happens. I know it's weird but sometimes the bilevel situation that using exhale relief creates can trigger central apneas in some people.

Seems like I am sleeping. Not all nights but most. On a lot of these I'd say the first 30 to 40 minutes can have sleep/wake junk pretty often. But like that night with the 14.34... I did have a hard time falling asleep and it looks bad for the first 30 minutes, but I was definitely asleep at 5:00, and if I zoom in past that point it's still pretty bad. I did start taking Metformin again (500mg morning, and again at night) for my T2 diabetes. But that was back in February, so I'm not sure if it's related or not.

And yeah, ugly is the right word. It's been almost as bad lately as before I started therapy. Although oddly, I still feel rested enough *most* days, despite the complications. I wonder how much of this is stress with everything going on in the world today, but I haven't seen any literature indicate centrals or hypopneas can be caused by general stress.

[tomkatt]

Oh, and regarding your reply on the other forum, I can't sleep without some exhale relief. I tried it previously but the pressure is too much and I start feeling choked for air. I can go as low as A-flex 1, but turning it off doesn't work for me. Generally I keep it at A-Flex 2. I'll try setting it down to 1 tonight.

One thing I'm noting too is in the past when I've had some good nights, and when I was sleeping best in the past year, I had a pretty narrow pressure range. Like 9-11 or 9.5-11. Would it be worth narrowing down to that again and testing? I tend to keep the range wider because if I have an OB that needs pressure above that it ends up waking me or causing snoring. It's not super common, but it happens.

[Pugsy]

Then try AFlex at 1 and lets see what happens. I have seen miracles happen with as little as 1 cm change in the pressure support that bilevel (which is what exhale relief does)....so maybe you will see a miracle.

I have a friend who gets around 15 centrals PER HOUR average with pressure support of 4 (she has a bilevel machine that will do 4 cm PS) and since her starting pressure is 16 EPAP (she needs that much do deal with her OSA and thus really needs some exhale relief) so....we dropped the PS to 3 and her centrals essentially went away. She gets maybe 1 per hour or less average and we can live with that.
I thought for sure she was going to need one of those high dollar ASV machines but a little 1 cm change in PS was all we had to do.
So miracles can happen.

Now...all that said...I am not so sure that your centrals are even real asleep centrals but instead are a reflection of a lot of SWJ and poor sleep quality. I would need to see a lot of detailed zoomed in stuff and maybe even have a copy of your SD card to look through many nights of flow rate and that's a lot of work for both of us.
How about trying simple and easy first....reduce Flex and see what happens.

Also...the next time you have a night where you don't sleep so great...reach over and turn the machine off and right back on again so we have some breaks in therapy we can easily see and know for sure you were awake and then we can immediately discount anything flagged during that time frame.

If your centrals are indeed mainly SWJ stuff...we gotta figure out why the crappy sleep.
Any new aches and pains to mess with sleep? Are your glucose levels stable? They can mess with sleep.

Pick a pressure you are comfortable with and quit screwing around with them...you don't need much minimum and more pressure won't fix centrals anyway. Something around 8 cm minimum looks to be a good starting point.

[tomkatt]

Then try AFlex at 1 and lets see what happens. I have seen miracles happen with as little as 1 cm change in the pressure support that bilevel (which is what exhale relief does)....so maybe you will see a miracle.

...

Also...the next time you have a night where you don't sleep so great...reach over and turn the machine off and right back on again so we have some breaks in therapy we can easily see and know for sure you were awake and then we can immediately discount anything flagged during that time frame.

If your centrals are indeed mainly SWJ stuff...we gotta figure out why the crappy sleep.
Any new aches and pains to mess with sleep? Are your glucose levels stable? They can mess with sleep.

Pick a pressure you are comfortable with and quit screwing around with them...you don't need much minimum and more pressure won't fix centrals anyway. Something around 8 cm minimum looks to be a good starting point.

I do turn the machine off if I get up, but if I'm tossing and turning half asleep, it's probably still on. I'm not comfortable going too low (feels like I can't get enough air below 6.5 - 8 depending on the mask) so I'll lock it in at 8 - 11.5 and see what happens. Minimum 8 should be okay but if it still feels like I'm gasping, I'll max the min setting at 8.5, I know I can breathe comfortably enough there.

Regarding aches and pains... always to some degree. I lift weights regularly to address my diabetes and not be so medication dependent, so I'm often sore to some degree. Some days are better and some worse, but I don't consider it too much of a factor, as it's just been a part of life since 2014 or so. Glucose levels are good though. Generally between 95-105 mg/dL when I go to bed.

[tomkatt]

Well, it looks like miracles do happen.

Only particularly bad thing I noticed is that I had a bit more snoring than usual. Not *too* bad from the look of it, but I'm wondering if I need a bit more minimum pressure to stop that. Any thoughts?

[Pugsy]

Yep...wee bit more minimum should help with the snores. Your choice if you want to do it now or wait to see if last night was maybe just an off night of sorts.
Would also help clean up the OAs and hyponeas that aren't SWJ early in the night.

I like to make small changes and give them a few nights to establish a pattern before I go on to the next change myself because I know that sometimes we just have bad nights and it's not a more established pattern. More of a one off kind thing which I just usually ignore.
Even now I still sometimes have those and can't explain why.

And cross our fingers the miracle holds.

[tomkatt]

Thanks Pugsy. I'll leave the max where it is but bump the min to 8.5. Some of my best sleep in the past has been with a min of 9, so I don't think it'll hurt anything. And yeah, I'll keep hoping the miracle sticks. I need better sleep.