Switched to ASV - AHI is great, but still feel like I'm not sleeping well

[Sleeprider]

I've seen others say the same as you, but I cannot get min PS above 6. No matter what I do to min and max epap, what I do to max PS and switching from ASV to ASVAuto it seems I 1) cannot have a min ps > 6 and 2) the gap between min and max ps must be at least 5 and no smaller. I'm not sure if this is some kind of funky firmware issue? It definitely seems from searching the web this isn't always, or wasn't always, the case

Don't suppose you can think of something incredible obvious I've missed? Otherwise, yep, I'll go searching for the setup manual and see what I can dig up

Let's discuss this business of getting PS above 6.0.  Your last chart posted in December shows you were using settings:
Mode: ASVauto
EPAP min: 6.0
EPAP max 6.0
PS min: 2.0
PS max: 10.0

These settings provide a range of 8.0/6.0 to 16.0/6.0 and in the chart below resulted in zero AHI.  Fill me in on what is going on, and how you ever got the idea you needed PS greater than 6. I understand you have been conversing on your therapy with Jason at Axgsleepdiagnostics.  Fill me in on your current progress with a chart, and explain what you want. As I have already said, PS min and PS max must be more than 5 cm difference.  At PS min 6.0, the PS max must be 11.0. If have not raised your PS max, that is why you cannot set PS min higher.

[Sassbeek]

Let's discuss this business of getting PS above 6.0.  Your last chart posted in December shows you were using settings:
Mode: ASVauto
EPAP min: 6.0
EPAP max 6.0
PS min: 2.0
PS max: 10.0

These settings provide a range of 8.0/6.0 to 16.0/6.0 and in the chart below resulted in zero AHI.  Fill me in on what is going on, and how you ever got the idea you needed PS greater than 6. I understand you have been conversing on your therapy with Jason at Axgsleepdiagnostics.  Fill me in on your current progress with a chart, and explain what you want. As I have already said, PS min and PS max must be more than 5 cm difference.  At PS min 6.0, the PS max must be 11.0. If have not raised your PS max, that is why you cannot set PS min higher.

Always appreciate the help!

So on min PS, I can't get it to go higher than 6 no matter what I do. I can set max PS to anything I want (As high as 17), make min and max epap anything I want, try ASV or ASVAuto modes, and nothing works to get that number higher than 6 unfortunately, even changing any and all of those settings and powering the device off and on again with them selected. Hoping there's something silly I'm missing and that it isn't something happening with my devices firmware. Tempted to factory reset it, but would need to look into what that would entail before trying anything like that

Long story short on the why, yep my AHI on ASV continues to be 0.0 most nights, 0.2 to 0.4 on bad nights. But I don't feel like I'm getting a good night sleep and still feel tired. When speaking to Jason, he seems to think my breathing is not great (likely lots of RERAs) unless at quite a high IPAP. He thinks I may have UARS, but obviously caveats that that it's a guess, I am not diagnosed nor have I talked to anyone about that

So he wants to get my min IPAP up, but to do so, I need to increase my EPAP. I'm slowly doing so, but the problem is when I get it at 9 or above, my sleep is ruined by Aerophagia. I'm seeing if I can work my way up, though. Here's my last 3 nights (Settings were his recommendation), and from what little I know about how to read these charts and what Jason has seen, it does seem like my breathing is better especially when it's steady at higher ipaps (15 or more).

So, long story short, I may need a Bilevel device based on what he's telling me, but, for now I'm trying to get my EPAP as high as I can in order to get my IPAP higher. I can also increase max PS which may work, but he seems convinced what I need is a high base level of IPAP which I can't get this thing to do.

Very, very happy for you to tell me something completely different, I'm game to experiment and try anything

[Sleeprider]

Okay, I checked the clinical manual and the limit for PS min is in fact 0 to 6, so you can't get any higher with this machine. Keep in mind the intent of the ASV is to treat central and mixed sleep apnea, so an obstructive condition or disease that requires very high minimum PS is probably not anticipated, and would move towards the ST-A iVPAPS.

I always try to make room for aerophagia, and will compromise some therapy goals by reducing pressure to avoid causing the discomfort where it is an issue. I disagree with Jason's approach, and while pressure support and elevated positive end expiratory pressure (PEEP) have important applications, they are clearly not resulting in an improvement of therapy. Your goal of low AHI was already achieved. The remaining goal of comfortable sleep with fewer disruptions is being thwarted by this approach. Your previous 95% flow limitation was zero, but with this effort to force air down your throat has risen to 0.11. Your tidal volume has increased from 580 to 520 mL but Minute vent has dropped from 6.75 to 6.5 L/min. So you are cramming more air into every breath, but getting less overall minute ventilation. You have made inspiratory time greater than expiratory time. which is the very definition of flow limitation. What you are doing is counter-productive and not based on any clinical experience or recommendation I have ever seen. Who is this hack, and what are his credentials to prescribe these perverse pressures? Why do you need higher IPAP with your aerophagia condition? What purpose does that serve? Your respiratory statistics tell us you are ventilated beyond your vital capacity.

Let's get your EPAP back to 6.0, PS min 3.0 PS max 10.0, and just have a more comfortable night tonight.

[Sassbeek]

Okay, I checked the clinical manual and the limit for PS min is in fact 0 to 6, so you can't get any higher with this machine.  Keep in mind the intent of the ASV is to treat central and mixed sleep apnea, so an obstructive condition or disease that requires very high minimum PS is probably not anticipated, and would move towards the ST-A iVPAPS.

I always try to make room for aerophagia, and will compromise some therapy goals by reducing pressure to avoid causing the discomfort where it is an issue.  I disagree with Jason's approach, and while pressure support and elevated positive end expiratory pressure (PEEP) have important applications, they are clearly not resulting in an improvement of therapy.  Your goal of low AHI was already achieved. The remaining goal of comfortable sleep with fewer disruptions is being thwarted by this approach. Your previous 95% flow limitation was zero, but with this effort to force air down your throat has risen to 0.11. Your tidal volume has increased from 580 to 520 mL but Minute vent has dropped from 6.75 to 6.5 L/min.  So you are cramming more air into every breath, but getting less overall minute ventilation. You have made inspiratory time greater than expiratory time. which is the very definition of flow limitation.  What you are doing is counter-productive and not based on any clinical experience or recommendation I have ever seen.  Who is this hack, and what are his credentials to prescribe these perverse pressures? Why do you need higher IPAP with your aerophagia condition? What purpose does that serve? Your respiratory statistics tell us you are ventilated beyond your vital capacity.

Let's get your EPAP back to 6.0, PS min 3.0 PS max 10.0, and just have a more comfortable night tonight.

His logic, and it made sense to me as presented but I am FAR from an expert obviously, is while my AHI is low he suspects my RDI is still high and having looked at my data he can see lots of what he suspects are RERAs. So that's the goal with the higher IPAP, trying to resolve any stubborn RERAs as even with my AHI low (or non existent) I feel like I'm still not sleeping well but when the device has periods of holding a higher, stable IPAP I seem to breath better which is pushing us towards thinking about a Bilevel of some kind. When using the settings above, or similar ones, I'd sleep comfortably (I don't mind the machine uncomfortable at all, outside of Aerophagia which is a non issue on low EPAP) but my sleeping still isn't great and Jason thought my breathing did not look good - obviously, I'm only so good (read, not good at all) at interpreting that myself. I'm always happy to try them again but in the past they didn't seem to result in a good night sleep

Do you see anything differently? Basically, if my AHI is so low and my sleep, seemingly, is not great even at those settings, what do you think a logical next step to try would be?

[Sleeprider]

We can spot RERA, and they typically show as spikes above the median inspiratory maximum on the flow rate graph. True RERA is an increasing flow limitation followed by an arousal. You have to have flow limit for RERA to occur. Your flow limits have increased with the higher pressure support. Compare the irregularity of the flow rate of current graphs with what we were working on in December. Compare the "flatness" of the inspiratory peaks. Do you see improvement, or clear signs of a bigger problem? How do you feel?

We never moved to a more detailed review of your flow rate and worked withing the pressure parameters of your aerophagia. We also have not fully investigated why your flow limitation is inconsistent and occurs in episodes that resemble positional obstruction. There are plenty of possibilities to reduce RERA and inconsistent treatment, without encroaching on your aerophagia. That said, Jason's objective of increasing IPAP or total pressure support is not unlike where we began this thread, the difference is I never suggested PS min as a way to get there, and ASV uses that IPAP in a way very different from ST or iVAPS, which seems to be more in-line with your other coaching.

[Sassbeek]

We can spot RERA, and they typically show as spikes above the median inspiratory maximum on the flow rate graph. True RERA is an increasing flow limitation followed by an arousal. You have to have flow limit for RERA to occur. Your flow limits have increased with the higher pressure support. Compare the irregularity of the flow rate of current graphs with what we were working on in December.  Compare the "flatness" of the inspiratory peaks.  Do you see improvement, or clear signs of a bigger problem?  How do you feel?

We never moved to a more detailed review of your flow rate and worked withing the pressure parameters of your aerophagia. We also have not fully investigated why your flow limitation is inconsistent and occurs in episodes that resemble positional obstruction.  There are plenty of possibilities to reduce RERA and inconsistent treatment, without encroaching on your aerophagia. That said, Jason's objective of increasing IPAP or total pressure support is not unlike where we began this thread, the difference is I never suggested PS min as a way to get there, and ASV uses that IPAP in a way very different from ST or iVAPS, which seems to be more in-line with your other coaching.

All makes sense, and so far, as you suspect, not feeling any better yet. But, given I'm working with Jason, I'm going to give his ideas a shot for a few days at least and fully exhaust everything there

If it doesn't work, and you suspect it won't, what would be the best approach? What would you need from me to deep dive further for the more detailed review? I'm happy to provide anything you want or would find useful

[Sleeprider]

That is the question of the year. I am always suspect that once therapy is resolving the respiratory issues, that additional problems with sleep quality may be external to the therapy. I simply know, the path you were on was disruptive to your respiration, and had cut back the hours of therapy you previously got. There is a tendency to lump all sleep problems into an assumption that something must be wrong with the therapy. I don't think that was necessarily the case, however all we can do is to make it as good as possible, and you were heading in the opposite direction.

[Sassbeek]

Alright so tried your suggested settings, Sleeprider! Thanks again for the help

A couple of things stood out to my eye, and again fully acknowledge I know next to nothing here

Flow limitations went down exactly as you said, my 99% at 0.63 here

Resp rate went up, 95% at 18.20, at the higher settings this has been in the 15-16 range. I read somewhere that something more in the 12 range is optimal here, but again know nothing about that - is this something I should even look at?

The main negative that I can see is what we were going for with the higher IPAP. I've attached an example of something I'd see pretty often when the device is holding a high (say 15-19) ipap steady for me. That's what looks like pretty optimum breathing, right? On lower ipap nights, like last night, I just don't see breathing patterns that look like that. I can attach an example of what is more typical those nights, but it's a much more subtle but consitent increase/decrease of the flow rate and very 'pointed' tops, not sure if that's anything to be concerned about

Either way, anything you'd want me to focus on or zoom in on here, and in general, how does this look? I still don't feel like I slept great but it's only one night so happy to be patient and keep going at this for a longer time

[Sleeprider]

I prefer to look at the median respiration rate rather than the 95th percentile as representative of your actual respiration rate. While flow limits don't tend to show up until the 95th percentile, and that represents the best statistical indicator for FL, respiration is quite different. So your median resp rate is about 15.2 and is completely normal, at least I hope so as mine seems to run between 14.6 and 16.0. A sleeping respiration tends to be a bit more rapid and smaller in volume than daytime, especially in REM.

Your example at high IPAP is an anomaly that is not what we're looking for. While the breaths seems very regular, it is the adaptive pressure support that is driving respiration at a rate of only 7.4 BPM. This is not spontaneous respiration, but it's pretty amazing that the inspiration wave is so sharp. This is often where we see flow limitation as the machine is pushing the inspiration, rather than spontaneous effort. Normal is when the PS is low and spontaneous drive is accomplishing respiration. We should compare this to a period of low PS at 03:33.

[Sassbeek]

Thanks for the background on resp rate, at least that's one area that looks for sure under control then. 

Ah, how best to tell when the breathing isn't spontaneous? Is there a tell tale sign of some kind that I could easily pick out?

I've attached a stretch from 3:33 onwards for you for comparison, how does this look? I had thought this breathing would be considered somewhat not great, the waves are not uniform and the size of inhale and exhale seems to be less consistent but, again, I am far from an expert and happy to be told I'm wrong. This type of breathing is very typical for me at lower ipaps, it more or less alternates from breathing that looks like this, some pauses (Which I believe are position changes) and some more 'wavey' breathing which I believe may be REM sleep, but obviously that's a guess on my part

Do you see anything there, or anywhere else you'd love to zoom in on? I slept with these settings again last night but, frustratingly, forgot my SD card but it felt like a very similar sleep. It felt light, with me frequently being aware I was awake, and I'm not especially rested but it's not as bad as when I was on CPAP. Anything worth focusing on or needs further investigation?