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Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
(09-01-2021, 06:42 PM)SarcasticDave94 Wrote: I'm in agreement with Gideon. Sorry I actually forgot what you were on, a DreamStation SV Auto. That's why my comment was a bit of a disconnect.

Of course! No worries at all. I'm surprised any of us can even have these long-term discussions given how many posts there are that you all keep on top of. If the roles were reversed, I couldn't do it!
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
Frequently we can identify a trend or even success is a day or two. Not you.
The most important thing for you to avoid is to try one approach today and another tomorrow. Give each theory a chance to develop or not.
Also UARS is hard to visualize in the data so we mostly have to rely on perceptions, yours.
The end goal is solid comfortable sleep, even if it's from a non pap solution
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
Imo things are clear.

Results declined significantly after removing the machines handcuffs. Mixture of central apnea, restrictions and Phillips Respironics programming lead to too high of average PS which is hurting sleep quality rather than helping. You went from ok looking results with the machine handcuffed to 3.5 PS to poor looking results every other night when PS runs too high. At first you thought were seeing positive results due to placebo effect and hoping changes would help whereas now it is becoming obvious that sleep quality has actually declined.

Imo you have two options.

Option 1: Try PSmin of 3 to see if that reduces machine targeting too high of PS. The machine has the capability to treat flow limited breaths and will continue to treat UARS better than fixed PS of 3.5.

Option 2: Handcuff PS again. Can set at fixed PS of 3.5 and if you want to proceed with Gideons theory than just keep trying to increase it in small amounts.

I personally am not convinced you need higher PS or that your remaining symptoms are UARS related.
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
(09-01-2021, 07:27 PM)Gideon Wrote: Frequently we can identify a trend or even success is a day or two.   Not you.
The most important thing for you to avoid is to try one approach today and another tomorrow.  Give each theory a chance to develop or not.  
Also UARS is hard to visualize in the data so we mostly have to rely on perceptions, yours.  
The end goal is solid comfortable sleep, even if it's from a non pap solution

I agree with all of that. And I really, really do appreciate all of the advice and help over the last year. 

What non pap solutions are there, basically surgery? 

Is it possible for me to be seen professionally in the US coming from the UK? As in, I fly down, see a specialist who does whatever they do, and then fly back with the right settings (or surgery recommendations or whatever)? 

(09-01-2021, 11:01 PM)Geer1 Wrote: Imo things are clear.

Results declined significantly after removing the machines handcuffs. Mixture of central apnea, restrictions and Phillips Respironics programming lead to too high of average PS which is hurting sleep quality rather than helping. You went from ok looking results with the machine handcuffed to 3.5 PS to poor looking results every other night when PS runs too high. At first you thought were seeing positive results due to placebo effect and hoping changes would help whereas now it is becoming obvious that sleep quality has actually declined.

Imo you have two options.

Option 1: Try PSmin of 3 to see if that reduces machine targeting too high of PS. The machine has the capability to treat flow limited breaths and will continue to treat UARS better than fixed PS of 3.5.

Option 2: Handcuff PS again. Can set at fixed PS of 3.5 and if you want to proceed with Gideons theory than just keep trying to increase it in small amounts.

I personally am not convinced you need higher PS or that your remaining symptoms are UARS related.

Thanks Geer1, I mostly agree, aside from three points. 

First, monday was my best day in years. Far beyond anything so far, far beyond previous placebo or other attempted solutions over the last few years. Even when I started stimulant medication for ADHD, which masks UARS well, it wasn't this effective. 

Second, I had sleep paralysis, snoring, hold my breath, ehs, etc before my machine. I've been cured of these since starting my machine, and on days I accidently sleep without it I've had paralysis again etc. At the PS I've been on most (3 and slightly above) I still snore at times and occasionally hold my breath and such. 

Third, my flow rate almost always shows issues (at least prior to asv) and I can often predict when my flow rate is worse based on how I feel, before seeing any data. 

The second and third points together make me believe that it's more likely that I do have SDB and haven't successfully treated it, rather than having SDB with no symptoms other than sleep paralysis and a mysterious additional condition that doctors, psychologists, and lifestyle doesn't address. The latter is certainly possible, but I think it's safe to say SDB is present, and it's also not unreasonable to assume I haven't successfully treated it yet. 

Update on today. Woke up easily, clearer headed and more motivated. Like Monday but not as obvious. Second best day - again with a bit too little sleep. Will check data when I'm home from work. 

I think I'll look for trends after 2 weeks on current settings, but if positive days are placebo or flukes then I suppose option 1 makes the most sense? 

Ultimately with the ASV we've seen an incredibly high abundance of timed breaths from a tiny tiny CA/hour, and haven't really tried changing any settings yet. Unless I'm missing something, I think that could be explored further. I get the feeling that a lot of timed breaths with flow limits or H events when transitioning between that and natural breathing leads to my current bad days, and less timed events or smoother transitions lead to my good days. But I'll analyse tonight to confirm or not.
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
I am confused. One day you say results are better, another day you say things are worse then you say things seem better again. Which is it?

You say you get the feeling things can be improved regarding timed breaths. I agree and personally think it is done by reducing PSmin.

Your PR ASV targets a flow rate and it increase PS above PSmin to try and maintain said flow rate. If you have a range of PS then the machine will increase PS when you start having lower amplitude restrictive breaths. PSmin is only a starting point and is not near as critical when using a range of PS compared to before when you were using a fixed PS. When you used a fixed PS you had to try and use a higher PSmin because the machine wasn't going to do anything to help you when you had moments of higher restriction. Now that you have uncuffed the machines PS you can get by with a lower PSmin because the machine will increase PS when restrictions are present. This is the exact reason auto CPAP machines were invented (they allow lower minimum pressure because the machine will increase pressure when needed).

The problem now is that you are playing on the verge of improved or worsened treatment. On the nights where your central apnea/depressed respiration does not react average PS stays low and you have a good nights sleep. On nights where things act up the machine ends up using higher average PS, relies on timed breaths/backup rate and you feel worse because you are creating more issues from central apnea basis than what restrictive breathing was causing before. The hard part is finding the perfect middle ground where you treat restrictions and don't induce respiratory depression. Jmo.
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
(09-02-2021, 07:27 PM)Geer1 Wrote: I am confused. One day you say results are better, another day you say things are worse then you say things seem better again. Which is it?

You say you get the feeling things can be improved regarding timed breaths. I agree and personally think it is done by reducing PSmin.

Your PR ASV targets a flow rate and it increase PS above PSmin to try and maintain said flow rate. If you have a range of PS then the machine will increase PS when you start having lower amplitude restrictive breaths. PSmin is only a starting point and is not near as critical when using a range of PS compared to before when you were using a fixed PS. When you used a fixed PS you had to try and use a higher PSmin because the machine wasn't going to do anything to help you when you had moments of higher restriction. Now that you have uncuffed the machines PS you can get by with a lower PSmin because the machine will increase PS when restrictions are present. This is the exact reason auto CPAP machines were invented (they allow lower minimum pressure because the machine will increase pressure when needed).

The problem now is that you are playing on the verge of improved or worsened treatment. On the nights where your central apnea/depressed respiration does not react average PS stays low and you have a good nights sleep. On nights where things act up the machine ends up using higher average PS, relies on timed breaths/backup rate and you feel worse because you are creating more issues from central apnea basis than what restrictive breathing was causing before. The hard part is finding the perfect middle ground where you treat restrictions and don't induce respiratory depression. Jmo.

Yes, it changes day to day. Monday was great. Tuesday and wednesday were awful. Today has been pretty good. Sorry if I wasn't clearer before. 

Constant PS means I don't get my absolute worst days anymore. But I don't get any good days anynore either. ASV I get a larger range for better and worse - I experience close to my worst days again (still no paralysis) and also get the odd good day that I haven't ever had. 

I think we are on the same page - perhaps the UK timezone mixed with my erratic sleep experience (and therefore schedule) obscures the timing of different messages. But like you mention, I seem to have good results some days when PS average is lower and worse results other days when PS average is higher. 

Thanks for clearing up PSmin, it makes a lot of sense and I think a lower PS is a good idea then. Does lowering it minimally, to 3, still make the most sense or should I just set it to something even lower since the machine can adjust upwards whenever needed?

I'll only be getting an hour or two of sleep tonight, so I'll discount any results tomorrow unless anything really different and interesting is observed.
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
I set PSMin to 2.5. Got 3 hours sleep so ignoring how I feel. Data-wise, timed breaths almost the entire night (1370 timed breaths).
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
(09-02-2021, 07:27 PM)Geer1 Wrote: ... 

You say you get the feeling things can be improved regarding timed breaths. I agree and personally think it is done by reducing PSmin.

... 

The problem now is that you are playing on the verge of improved or worsened treatment. On the nights where your central apnea/depressed respiration does not react average PS stays low and you have a good nights sleep. On nights where things act up the machine ends up using higher average PS, relies on timed breaths/backup rate and you feel worse because you are creating more issues from central apnea basis than what restrictive breathing was causing before. The hard part is finding the perfect middle ground where you treat restrictions and don't induce respiratory depression. Jmo.

With a PSmin of 2.5, my PS never went lower than 3.0 yet thousands of timed breaths still occured. I suspect this means decreasing PSmin further won't necessarily do anything, right? How do I achieve this balance you're talking about, or is it fruitless? Is there anything left to try after this, if it doesn't work?
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
Being unsure what the next steps are, I called an apnea charity. I'll be getting a home sleep study from them in a month and will post results. I'm also possibly able to get an apnea and uars supportive ENT evaluation next year (or later, depending on waiting list and covid). 

They said my particular machine needs registering due to a recall from some sort of cancer scare - I'll be looking into it more but if it turns out to be correct then my machine will be handed over. I might use this opportunity to get a different machine. What machine would you all recommend?

I've also been told that until I've got access to professional help, to try APaP mode if my machine allows. I'm not sure what APaP is - how would I do that?
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RE: Seemingly little correlation between EPAP (or PS) and AHI or flow rate. [UARS]
I discovered two settings I haven't noticed before, I assume due to being ASV exclusive and on a different menu.

Ti = 1.2
Rise time = 3

Are these numbers okay? I've done a little browsing on this forum and seen both mentioned and altered. I've no idea if that's important in my case.
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