Complex Sleep Apnea? Suggestions?

[Unkikonki]

Hi there,

I was diagnosed with OSA with an AHI of 27 back in March (see screenshot below). I've been doing unsupervised CPAP therapy (ResMed AirSense 10 Auto-PAP) for the last 3 months with rather disappointing results.

So far, the vast majority of events detected by the machine are CA. Far away, in second place, come Hypopneas. And that's it, no Obstructives or unclassified detected at all.

Could you take a look at the graph and tell me what you think please? Do they look like treatment-emergent centrals to you? And how about the hypopneas?

NOTE: I'm aware that the maximum pressure should probably be a bit higher, but historically it's always stayed below 12, even when set to 15. I will increase it to 12 regardless, but I don't think that's the main problem.

SLEEP STUDY





OSCAR - ENTIRE NIGHT



CLEAR AIRWAYS




HYPOPNEAS




MIXED: CLEAR AIRWAY + HYPOPNEA

[Miss Emerita]

Your sleep test used EEG channels, so if was able to detect whether you were asleep or awake throughout the night. Thus your report probably doesn't reflect clear-airway events that occurred after brief arousals; it reflects only CAs that occurred while you were truly asleep. This means we just don't know whether you had a lot of post-arousal CAs during the night of your test.

Your sleep test also showed a number of arousals, some arising from respiratory-related conditions and some "spontaneous" (meaning they didn't arise from respiratory-related conditions).

The Oscar zoomed-in charts are mostly or entirely showing CAs that follow arousal breathing. Arousal breathing tends to be deeper and more irregular than asleep breathing. It is often followed by CAs, though the exact mechanism that accounts for this is not entirely clear.

While your PAP therapy has done a good job with OAs, you're still having a fair number of hypopneas and snores, and your flow-limitation graph is fairly active.

I would suggest that for the moment, you bracket the CAs, since the real problem there is probably the arousals rather than the CAs themselves. As for the hypopneas and flow limitations, I would suggest that you introduce EPR, starting with 2. This may result in more CAs (and OAs), but what will be interesting to see is whether it reduces Hs and FLs. Is that an experiment you're willing to try?

[Unkikonki]

I would suggest that for the moment, you bracket the CAs, since the real problem there is probably the arousals rather than the CAs themselves. As for the hypopneas and flow limitations, I would suggest that you introduce EPR, starting with 2. This may result in more CAs (and OAs), but what will be interesting to see is whether it reduces Hs and FLs. Is that an experiment you're willing to try?

Hi Miss Emerita. Thanks a lot for your comprehensive response.

I have already tried that, and the results have indeed been exactly what you describe: almost no Hs to the expense of more CAs (see screenshot below). Do you think I should go back to those settings for the time being?

Your sleep test used EEG channels, so if was able to detect whether you were asleep or awake throughout the night. Thus your report probably doesn't reflect clear-airway events that occurred after brief arousals; it reflects only CAs that occurred while you were truly asleep. This means we just don't know whether you had a lot of post-arousal CAs during the night of your test.

Your sleep test also showed a number of arousals, some arising from respiratory-related conditions and some "spontaneous" (meaning they didn't arise from respiratory-related conditions).

The Oscar zoomed-in charts are mostly or entirely showing CAs that follow arousal breathing. Arousal breathing tends to be deeper and more irregular than asleep breathing. It is often followed by CAs, though the exact mechanism that accounts for this is not entirely clear.

While your PAP therapy has done a good job with OAs, you're still having a fair number of hypopneas and snores, and your flow-limitation graph is fairly active.

If all those CAs are being caused by arousals indeed, does it mean I shouldn't worry about them?

On another note, I'm starting to suspect that most events might be triggered by positional sleep apnea. Notice how there's barely any events during the first hour or so of sleep? I thought this was mainly because, from what I read, sleep apnea tends to worsen during REM sleep, and apparently deep sleep tends to make most of our sleep during the first cycle of the night. However, I'm starting to think that it might be because after an hour or so, I unconsciously turn on my back, which is the worst position for my apnea (I start the night sleeping on my left side).

One more thing. If you take a look at last night's data (graph below), I couldn't really fall back asleep from 6.00 am onwards. I was in light sleep at best, and yet look at the big number of events being displayed. I've been taping my mouth for a couple of weeks now, and during that 2-hour period (6.00 am to 8.00 am), the reason I couldn't fall asleep is because I was gasping for air through my mouth, which was completely blocked. This would happen over and over again, thus preventing me from falling asleep. This used to happen even when not taped, which would still wake me up. Interestingly, for some reason, it only seems to happen during the early morning but not during the night.

EPR 3



LAST NIGHT

[Miss Emerita]

Others may want to chime in on this, but I think it's the arousals, not the CAs, that are a cause for concern.

In the first chart you posted, you had a graph with O2 data, and as best I can make out, your O2 levels were fine all night. If you had a whole bunch of CAs that resulted in O2 levels staying below 90 for periods of time, then you might want to worry about the CAs themselves. Otherwise it's the arousals you want to worry about, both those that wake you up and those that just kick you out of deeper sleep into lighter sleep.

Try going through your patches of CAs with a zoomed in view and see whether you're seeing arousal breathing. My guess is that you will, but let us know if you don't.

So we know that EPR of 3 and a minimum pressure of 9.8 reduces your FLs, eliminates your OAs, and almost eliminates your Hs. In your place, I would stick with those settings for about a week to let your body get used to them. At that point we can consider some options, e.g., reducing EPR a little, reducing your minimum pressure, or using a fixed pressure. But those are for later.

I don't know that your sleep position will directly lead to CAs, but your sleep position could make your sleep less consistently solid (meaning you're having more arousals and hence more CAs). You could experiment with ways of trying to keep yourself on your side, e.g., by propping your back with a pillow.

When you were gasping for air, was that because your nose was stuffy?

[Unkikonki]

Others may want to chime in on this, but I think it's the arousals, not the CAs, that are a cause for concern.

In the first chart you posted, you had a graph with O2 data, and as best I can make out, your O2 levels were fine all night. If you had a whole bunch of CAs that resulted in O2 levels staying below 90 for periods of time, then you might want to worry about the CAs themselves. Otherwise it's the arousals you want to worry about, both those that wake you up and those that just kick you out of deeper sleep into lighter sleep.

Try going through your patches of CAs with a zoomed in view and see whether you're seeing arousal breathing. My guess is that you will, but let us know if you don't.

You are right. Most of CAs are preceded by an irregular breathing pattern. What could be causing those arousals? Is it just me changing positions?

So we know that EPR of 3 and a minimum pressure of 9.8 reduces your FLs, eliminates your OAs, and almost eliminates your Hs. In your place, I would stick with those settings for about a week to let your body get used to them. At that point we can consider some options, e.g., reducing EPR a little, reducing your minimum pressure, or using a fixed pressure. But those are for later.

I don't know that your sleep position will directly lead to CAs, but your sleep position could make your sleep less consistently solid (meaning you're having more arousals and hence more CAs). You could experiment with ways of trying to keep yourself on your side, e.g., by propping your back with a pillow.

Got it. I'll do that. Besides, I've achieved my best AHI so far with the settings you suggest, so it makes sense.

I will also start looking for ways to keep myself on my side the entire night (I read about positional therapy but is it actually possible to remain in the same position throughout the entire night?).

When you were gasping for air, was that because your nose was stuffy?

No, I have no idea what's causing the gasping. My nose is as clear as it can be (got septoplasty + turbinoplasty done last June, and I use a nasal dilator or nasal strips to keep my valves wide open since they are a bit collapsed).

[Miss Emerita]

I don't know whether some people stay in the same position all night, but I suspect few do. If you're using a pillow to prop your back, you'll need to use two or rearrange the one when you turn over.

Arousals are a part of everyone's sleep. We tend to have more of them the older we get. It isn't a problem to have a short arousal if you can just drop back to sleep. It's when the arousals result in longer periods of wakefulness that they can mess with your sleep architecture. (That's the succession of sleep stages repeated throughout the night.) Those periods with a lot of CAs may well be periods when you're not sleeping, or barely sleeping, or having very choppy sleep. With luck, PAP treatment will in time allow you to sleep more soundly, so let patience be your watchword.

[Unkikonki]

I don't know whether some people stay in the same position all night, but I suspect few do. If you're using a pillow to prop your back, you'll need to use two or rearrange the one when you turn over.

Arousals are a part of everyone's sleep. We tend to have more of them the older we get. It isn't a problem to have a short arousal if you can just drop back to sleep. It's when the arousals result in longer periods of wakefulness that they can mess with your sleep architecture. (That's the succession of sleep stages repeated throughout the night.) Those periods with a lot of CAs may well be periods when you're not sleeping, or barely sleeping, or having very choppy sleep. With luck, PAP treatment will in time allow you to sleep more soundly, so let patience be your watchword.

I changed the settings like you suggested and my AHI has dropped significantly; also, only 3 Hypopneas. However, it wasn't a good night of sleep overall because I was too concerned with not allowing myself to sleep on my back (I tied a tube of tennis balls to my back but it came loose). Big mistake. Maybe for now I shouldn't really care much about my position as much as I should care about sticking to the same CPAP settings for at least a week or two. What do you think?

[zonker]

....(I tied a tube of tennis balls to my back but it came loose). Big mistake. Maybe for now I shouldn't really care much about my position as much as I should care about sticking to the same CPAP settings for at least a week or two. What do you think?

always a good idea to stick with your settings for awhile as it can time for the body to adjust.

as to the tennis balls, you might try putting them in a fanny pack.

good luck!

[Miss Emerita]

Good suggestion from Zonker. You can also just not worry right now about sleep position, as you say.

[Unkikonki]

UPDATE: treatment hasn't improved, centrals are still very prominent. I used the same settings for 9 days (Min 9.8 Max 12.4 EPR 3) and then slightly changed them to Min 10 Max 12.4 EPR 2 during the last 5 days. The results haven't really changed much from what they used to be. My AHI keeps fluctuating between 5 and 9, and I keep waking up feeling tired.

That being said, using the machine is still better than nothing, as I confirmed during the 3 nights I slept away from home without the machine (28/12 to 30/12).

After 4 months of continuous use, do you think I am well past the acclimatization stage? I mean, if the centrals haven't decreased by now, is there any change they will in the future? Could it be something else?

[Pugsy]

After 4 months of continuous use, do you think I am well past the acclimatization stage?

Assuming that you were indeed asleep when those centrals got flagged I do think that you are probably looking at treatment emergent central apneas and while sometimes time helps the body adjust and the centrals can go away.....doesn't look like you are going to be that lucky. I have heard of it taking about 6 months but most of the time 3 months is long enough to know if there is a chance they will go away on their own.

About all you can do with your current machine to maybe (stress the maybe part) is try turning EPR off and that only helps if EPR itself is the trigger for the centrals.
I did look at your change in settings section and while you haven't tried EPR being off more than a handful of times....when you did try it I don't see that it helped much if any.

if the centrals haven't decreased by now, is there any change they will in the future?

IMHO....chances are slim that given more time the centrals will reduce on their own.

Could it be something else?

Altitude might be a factor....where you live....what altitude is it?

My personal opinion is you most likely need the ASV model machine because it can deal with both obstructive apnea and central apnea.

[Unkikonki]

After 4 months of continuous use, do you think I am well past the acclimatization stage?

Assuming that you were indeed asleep when those centrals got flagged I do think that you are probably looking at treatment emergent central apneas and while sometimes time helps the body adjust and the centrals can go away.....doesn't look like you are going to be that lucky. I have heard of it taking about 6 months but most of the time 3 months is long enough to know if there is a chance they will go away on their own.

About all you can do with your current machine to maybe (stress the maybe part) is try turning EPR off and that only helps if EPR itself is the trigger for the centrals.
I did look at your change in settings section and while you haven't tried EPR being off more than a handful of times....when you did try it I don't see that it helped much if any.

Hi Pugsy, thanks for looking into it. Yeah, that's why I reduced EPR from 3 to 2. My plan was to gradually bring it down and see how it goes. I've learned better than to make sudden drastic changes to my settings. I will keep EPR at 2 for a few more days and then drop it to 1.

Could it be something else?

Altitude might be a factor....where you live....what altitude is it?

My personal opinion is you most likely need the ASV model machine because it can deal with both obstructive apnea and central apnea.

I live in Auckland, New Zealand, which is at sea level.

What would the best way of checking whether an ASV model might help? I was considering doing a L1 PSG study in a lab, but it's quite expensive.

Also, I have an appointment in a couple of days with the Clinic that diagnosed me with OSA (L2 PSG) to go through the current CPAP settings and data (they didn't provide the machine so they haven't been supervising treatment).

[Pugsy]

What would the best way of checking whether an ASV model might help? I was considering doing a L1 PSG study in a lab, but it's quite expensive.

The best way is of course that in lab sleep study while actually using the ASV.
That's the "best" way but yes....it is very expensive just for the sleep study and then there's the cost of the machine which isn't cheap. They are very pricey.

Now if you could just rent an ASV machine....to see if it works for you or not....that is also an option.
Figuring out what settings to use would take a little bit of trial and error but it can be done..

I know nothing about insurance in New Zealand....do you have insurance to help you out with the costs of the sleep study and the ASV machine???

[Unkikonki]

What would the best way of checking whether an ASV model might help? I was considering doing a L1 PSG study in a lab, but it's quite expensive.

The best way is of course that in lab sleep study while actually using the ASV.
That's the "best" way but yes....it is very expensive just for the sleep study and then there's the cost of the machine which isn't cheap. They are very pricey.

Now if you could just rent an ASV machine....to see if it works for you or not....that is also an option.
Figuring out what settings to use would take a little bit of trial and error but it can be done..

I know nothing about insurance in New Zealand....do you have insurance to help you out with the costs of the sleep study and the ASV machine???

Right. Well, even if it's expensive, if it has the potential to fix my sleep for good, it's totally worth it. My insurance will cover part of the sleep study but no the ASV/CPAP machine (I'm currently renting the CPAP, will check if the same company rents out ASVs). I will discuss it with the specialist on Wednesday. Thanks heaps