I don't get it! AHI still high

[mellocello2003]

To clarify, yes, A-Flex 1 was what I've been using for a while. The only change now is to change the min and max pressure ranges for auto from 9-15 to 11.

[mellocello2003]

Is there any reason why I seem to have more OA's on higher pressures? Could the drastic changes in pressure be causing OA's? All of this seems really quite absurd and non-sensical.

[mellocello2003]

OK. I didn't actually read Den's response:

Notice in the reports that your apnea events are higher when your pressures ramp up and are fewer when your pressures are lower. Switching to straight pressure makes the machine stop responding to snores and flow limitations......which should improve the quality of your sleep.

What is it about pressure changes that cause more obstructive apneas to occur?

[Wulfman...]

OK. I didn't actually read Den's response:

Notice in the reports that your apnea events are higher when your pressures ramp up and are fewer when your pressures are lower. Switching to straight pressure makes the machine stop responding to snores and flow limitations......which should improve the quality of your sleep.

What is it about pressure changes that cause more obstructive apneas to occur?

I wish I knew that answer for sure, but I've seen it many times in people's reports. My "guess" is that it has to do with the person's subconscious reflex (resistance) reaction to the higher pressures......all it takes is about 10 seconds for the machine software to score it as an apnea. For some, it could also be sleeping position and any number of things.

Den

.

[Pugsy]

What is it about pressure changes that cause more obstructive apneas to occur?

The pressure changes (increases) aren't causing the obstructive apneas to occur.

Here's how APAP works...it really just responds to apnea event warning signs or what I call precursors. It monitors your air flow and looks for Flow limitations and snores mainly. This is because flow limitations and snores are the first indicators that a collapse of the airway is in the works. Once an apnea event has grown up enough to meet criteria for an obstructive apnea or hyponea the machine doesn't really do anything except sit and wait for the air flow to return to somewhat normal and then it takes its job back up and tries to prevent it from happening again.
When the minimum pressure is too low it can't respond quickly enough so it is always trying to play catch up with those snores and limitations and trying to prevent them from growing up to become a full fledged apnea or hyponea.

All this up and down of the pressure can disturb some people's sleep...the variations in pressure themselves can disturb sleep for some people. Not everyone of course but some people. Wulfman...now he noticed every little pressure change when he used APAP mode...and found it highly disruptive to his sleep. Now me...I can sleep right through the machine going up and down all night between 10 and 20...never know it occurs till I see the reports.

Wulfman likes to suggest cpap mode because he has first hand experience how the varying pressures can be a disturbing factor. The down side to cpap mode is that person has to use maybe higher pressures all night instead of part of the night.
But if pressure changes are a disturbing factor it is better to use fixed pressure and get maybe better sleep without the pressure variations maybe being a disturbing factor. Sometimes we just have to make compromises.

Now me...since I can sleep through hurricane force winds...I tend to take the approach to use apap as designed so that I don't have to use higher pressures all night long. I would much rather use 10 cm for 75% of the night and maybe see 18 or 19 the other 25% of the night. But that's me and those pressure changes don't bother me.
So often I will offer a compromise if someone doesn't want to use higher pressures all the night but the pressure changes may be bugging someone...compromise with a tight APAP range...sometimes real tight. It all depends on what a person ends up feeling is working best for them in their situation. I don't think any one way of doing something is the best way to do things for 100 % of the population.
But I always try to find out if the pressure changes are a potential factor and if they are...then at least give cpap mode a try...it sure won't hurt. Since the PR S 1 machine allows a minimum and maximum to be the same I like to suggest a fixed setting like I did with you...minimum to equal maximum and that way we have the Flow Limitation data...it's there for a reason. It doesn't hurt anything at all to make the APAP work like cpap and we gain FL data.

Now, as to why you are seeing the clusters and the times when it is obvious the pressure is not sufficient...it isn't related to the pressure increase...the pressure increases are the machine trying to adapt to a period of time that for some reason your OSA is requiring more pressure. The 2 most common culprits for needing more pressure during part of the night where we see clustering....supine sleeping and/or REM stage sleep.
For some reason your airway needs more pressure to prevent the tissues from collapsing.
Both are very common...my higher pressures pushing 20 are REM stage sleep related and supine sleeping doesn't seem to make any difference but I know one man who needed 19 cm when sleeping on his back and only 9 cm on his stomach. Guess what he decided to do..he decided to retrain his body so that he never slept on his back.
I can't do anything about REM sleep...so I have no control. My option was use much higher pressures all night to prevent the REM events that require 18 or 19 cm that would be cpap mode and that wasn't a real attractive option to me....or I could use APAP mode and let the machine do its job. Since changing pressures didn't disturb my sleep..hey I am good with letting the machine figure it out.

So for you....increase the base pressure in hopes of taking a more proactive preventative stance to actually stop the collapse before those snores and FLs grow up to be full grown OAs or hyponeas.
Combine it with mimicking cpap mode to eliminate the pressure changes as a possible factor in your overall crappy sleep.

[mellocello2003]

OK. Here's what I'll do. I'll increase the base pressure from 9 to 10. And just for kicks, I'll increase the upper limit from 15 to 20 (even though, according to many, it shouldn't make a difference unless I'm hitting my upper boundary).

Thanks so far for all the help.

[Wulfman...]

What is it about pressure changes that cause more obstructive apneas to occur?

The pressure changes (increases) aren't causing the obstructive apneas to occur.

I was also thinking about higher pressures in general.
I forgot (at least) one scenario. If a person has GERD-related issues (known or unknown as there's a "silent" version) it can raise Hell with an APAP changing pressures. Here's a couple of links (copy into your browser and take out the spaces). The second one has posted reports.

http : // www . cpaptalk . com/viewtopic . php?f=1&t=8843&p=95185&hilit=+GERD+Auto#p95185

http : // www . cpaptalk . com/viewtopic . php?f=1&t=1800&st=0&sk=t&sd=a&start=30

Den

.

[Pugsy]

And just for kicks, I'll increase the upper limit from 15 to 20 (even though, according to many, it shouldn't make a difference unless I'm hitting my upper boundary).

That's not what I meant.

Here's the deal if your base pressure does a good job...the pressures are unlikely going to need to range as much BUT the machine can and will try to fix some snores that might not really need more pressure and the variations and increases could potentially cause some aerophagia issues and/or mask leak issues with ever changing pressures and/or simply cause your sleep to be disrupted.
A better base pressure should prevent wide changes but it isn't a guarantee.

If I were in your shoes and also heeding Wulfman's sage advice....
I would try to mimic cpap mode with APAP set minimum set to 11 and maximum set to 11.
If 11 cm seems uncomfortable for some reason you could try 10 and 10 but I don't think 10 is going to be quite enough but maybe compromise with my love for APAP range and Wulfman's love for fixed pressures with a tight, tight APAP range?? Like 10 minimum and 12 maximum.

If the minimum can do a good job the machine shouldn't max out very much at 12. Eliminate the possibility of the wide pressure variations impacting overall sleep quality. It sure won't hurt and might help.

[mellocello2003]

A lot of my apnea events appear to occur where the pressures are much higher than 10 or 11. All things being equal, if we drew a line at 11, I would still be having a crappy sleep. This is why I opted for continuing with APAP therapy...

Also, I understand the point of trying to eliminate wide pressure variations as a cause for *issues*, but I thought you also previously said that those issues were going to manifest themselves in terms of decreased sleep quality (not necessarily caused by higher AHI).

Are you seeing examples of non-responsive apneas in these graphs, also?

Thanks

[mellocello2003]

You understand, I'm basically scared to use a straight up fixed pressure setting, one that is lower than where I was actually seeing apnea events in the graphs.

[mellocello2003]

I'll try tonight at min 11 and max 11 and post the results tomorrow.

Thanks so far for the help.

[Pugsy]

You understand, I'm basically scared to use a straight up fixed pressure setting, one that is lower than where I was actually seeing apnea events in the graphs.

Okay, I understand. Go ahead and set the maximum wider if you want.
Maybe we won't even need it and you can always try a more limited range later. You don't have to do it all in one night.
I do think that the minimum pressure is the most critical pressure.
Trust me...if the minimum can do a better job then the maximum won't have to do so much work.

The idea is prevention...not fixing after the fact.
Right now the minimum pressure can't get to where it needs to be quickly enough. If we give it a better head start with more minimum hopefully it will be able to do a better job preventing and trying to play catch up after the fact.

Your pattern of events strongly suggests REM sleep. You may be like me...sometimes those REM events must be on steroids and it takes a lot to prevent them. I have nights where pressure doesn't change very much at all and I have nights were I might spend an hour up around 20. We don't sleep the same each night.

Let's see if we get the events prevented better...break up the clusters...if you still feel crappy with a good report on paper then we can visit fixed pressure or tight range of pressures just in case your are sensitive to pressure changes. We don't have to do it right now.

just as I hit submit I see now you want to use 11/11. That's fine too...whatever you are comfortable with....

[mellocello2003]

Well, I didn't care so much about the max. It was really just increasing the min and keeping it on APAP, because of those times when I really do need higher pressures.

That being said, I also like the concept of keeping the range relatively small. So, ugh, final tweak - I'll make it 10-15.

Let's see how it goes.

[mellocello2003]

Pugsy, how do you like the TAP PAP, by the way?

[Pugsy]

The Tap Pap replaced my Swift FX nasal pillow mask by the second night I used it.

You would have to know me a little better to understand my priorities and know the things that hold a higher place in my list of preferences. I have always preferred the least amount of stuff as possible on my face and my head.
The Swift FX came as close to that priority as any thing ...then this weird looking thing with no headgear came out and it was really interesting...Something about it got my attention.

I love it. I don't use the headgear that came with it...no need.
We have a thread where a lot of us talk about it. Lot more details.
viewtopic.php?f=1&t=87232&st=0&sk=t&sd= ... Pap+Review