Lanky Lefty 27 & APAP

[SJ-Paddler]

This popped up on my YouTube suggested watch list.

https://www.youtube.com/watch?v=6t1z-SOmTto

He talks about APAP algorithms and how they work and how they are all bad and to just put everything in CPAP only mode.

His opinion for sure, and I appreciate his opinions, but I think the way he described these algorithms was wrong.

He said the machine would increase pressure AFTER you had an event and that was the reason they were bad because they did not prevent events. Please correct me if I am wrong but I don't think they work that way. They should be monitoring the Flow Restriction and increase pressure BEFORE an event, to prevent an event.

To confirm, is that how you guys understand things also? I am pretty sure I read that somewhere in the ResMed manual. Any comments about the video?

Thanks.

[Rubicon]

He said the machine would increase pressure AFTER you had an event and that was the reason they were bad because they did not prevent events.

That's exactly how they work. They can't work any other way. They need to see a complete event in order for the Decision Tree to begin. What it will do, however, is prevent (sometimes eventually) the next event.

[Insert endless combinations and permutation here, i.e. body position, sleep stage, wide open 4/20 settings, ASV aka "Let's bludgeon everything no matter what is is", hey it's only a yawn WTF you doing etc.]

[Rubicon]

What you can do though, is figure out "ideal" pressure and set pressure there so it doesn't have to run the algorithm all night.

[Insert endless other permutations and combinations here...]

[Pugsy]

Jason is a great guy but he is like everyone else on this planet....not perfect in their thinking.

He's right about one thing though....the machine doesn't do anything during an event and only increases the pressure after the event happens and usually either has some other criteria that has happened or more events and then the machine does some thinking and decides to increase the pressure in an effort to PREVENT whatever just happened from happening again.

These machine's can't respond in the blink of an eye (except ASV machines can) and it's always been that way.
Yes, what Jason talks about "can" happen but that's when the machine's baseline minimum pressure isn't set up optimally.

The whole idea with using the auto adjusting algorithm is to set the machine to a minimum pressure that prevents the bulk of the airway collapses and then can also increase IF NEEDED for whatever outliers might be going on.
Special circumstances that cause a need for higher pressures short term.

I am a prime example of a good reason for using apap mode and not a fixed mode. I asked Jason one time what he would suggest I do given my REM worse OSA and a need for 6 to 8 cm MORE pressure in REM.
I get by just fine for all the other parts of the night I am not in REM with about 9 cm pressure but in REM I have seen upwards of 16 to 18 cm. By his thinking I need 16 all night long just to deal with the 20% of the time I am in REM.
It's doable I suppose but I am not fond of the idea and I bet I would be having aerophagia issues with that much constant pressure all night. Stupid ass idea IMHO. He hemmed and hawed a bit but would never give me a straight answer.
I don't fit his perfect mold and the fact of life is that most people don't fit his mold.

The minimum pressure IS THE MOST CRITICAL pressure setting though. Giving someone an apap set to 4 to 20 which is really the factory defaults with no thought to a real setting is in most cases going to end up with what Jason describes happening. Duh....easy fix....increase the minimum to act like that fixed pressure he wants to use but set a range that the machine can go to IF IT NEEDS TO GO up to deal with the special circumstances....like my REM worse OSA.
Or maybe for someone whose OSA is worse on their backs but they don't sleep on their backs all that much.

So I don't know why Jason is so reluctant to accept that auto mode can work if you set it up optimally to start with but that's just the way he is. I call it old school...just like some docs are old school.
When I set my machine to a minimum of around 8 or 9 and give it a range for the special circumstances and I see the machine go to over 12 and I have seen 18 cm...it can do a great job and I sleep right through the changes.

Jason also doesn't like EPR because it can cause centrals in some people. Well it doesn't cause centrals in everyone and I see no reason to punish 95% of the people who like or need EPR just because EPR "might" cause centrals in the other 5 % of the people. Actually I don't think that it is 5%....probably more like 2 %. We just see it here a lot because the people who don't have a problem aren't coming here to fix a problem they don't have.
We just get the problem people here. The people who don't have a problem have no reason to come here. So we do see more problems.

Like I said...Jason is a great guy and I love him to death but he is definitely an old school stick in the mud who just doesn't want to admit that auto mode can work as long as the minimum pressure is optimally set in the first place.
I respect his views...but I certainly don't agree with them.

Set the minimum in auto mode up better to PREVENT most events and then for the outliers like my REM sleep we let the machine sort it out.

Or I could use 15 cm all night....geez...that's a f'ing stupid idea. Why in the hell would I want to do that?

[palerider]

This popped up on my YouTube suggested watch list.

https://www.youtube.com/watch?v=6t1z-SOmTto

He talks about APAP algorithms and how they work and how they are all bad and to just put everything in CPAP only mode.

His opinion for sure, and I appreciate his opinions, but I think the way he described these algorithms was wrong.

He said the machine would increase pressure AFTER you had an event and that was the reason they were bad because they did not prevent events. Please correct me if I am wrong but I don't think they work that way. They should be monitoring the Flow Restriction and increase pressure BEFORE an event, to prevent an event.

They react to breathing events by increasing pressure after the event in order to prevent future events.

Snoring and flow limitations are events that cause pressure to increase, thus possibly preventing more severe events, like hypopneas and apneas.

Your statement (and possibly his?) doesn't take into account that there are different types of events.

bumping pressure up in response to flow limitations is *designed* to prevent subsequent apneas.

[SJ-Paddler]

He's right about one thing though....the machine doesn't do anything during an event and only increases the pressure after the event happens and usually either has some other criteria that has happened or more events and then the machine does some thinking and decides to increase the pressure in an effort to PREVENT whatever just happened from happening again.

You know I figured someone with his experience, and exposure, would not misrepresent the facts. I found what I saw in the ResMed manual and misunderstood part about "Flow Limit, Snore, AND Apena". Specifically the Apena part. I thought it was all Flow Limit based.

Regarding EPR - I am at 2 cm and boy when I changed to 3 cm the Clear Airway events went nuts. I went back to 2 cm just because I did not like looking at them.

[chunkyfrog]

I like APAP. A LOT!
I suffered for the first 9 months because the idiots responsible sold me an Elite
set several cm higher than I needed.
Luckily, I had a Flex plan, and was able to invest in an S9 Autoset from Cpap.com.
If not for that, I doubt that I would be alive today.
Jason is entertaining and easy to look at.
He has some really good ideas.
And one very bad one.

[Rubicon]

...he is definitely an old school stick in the mud

I think that's being overly generous.

In addition to your point about REM-dependent OSA, add in position-dependent OSA.

And an area that would create problems other than simply discomfort, generation of treatment-emergent apnea.

Let's say you need you need 12 cmH2O in REM but 6 cmH2O in NREM. 12 cmH2O in NREM causes treatment-emergent CompSAS.

You'll NEVER get stable.

Why, you ask, doesn't the CompSAS extend into REM? Cause you can't have central apnea in REM!

Or at least, it's rarer than finding Charizard in a tutu at a Trump rally.

I think the appropriate generalization here would be 4/20 is usually a bad idea.

[Pugsy]

And an area that would create problems other than simply discomfort, generation of treatment-emergent apnea.

Let's say you need you need 12 cmH2O in REM but 6 cmH2O in NREM. 12 cmH2O in NREM causes treatment-emergent CompSAS.

You'll NEVER get stable.

point taken and I agree but the number of people who actually might fall into the 6 cm (or whatever cm) works fine but higher causes treatment emergent CompSAS is going to be relatively small and we would of course deal with that should it happen simply by not allowing the pressure to go the higher threshold that is the trigger.

My point is that Jason's way of thinking would restrict everyone up front just because something "MIGHT" happen.
When the actual chances of that happening are relatively small.
He does it with using EPR....sure it can cause CompSAS in SOME people but the number that it actually does cause that problem is relatively small. Since exhale relief or bilevel pressures are most of the time a non factor in central triggering...why not use them. For the small number of cpap users that it does create a problem that is fixable by just eliminating bilevel/exhale relief we can easily just eliminate the bilevel situation.

[chunkyfrog]

As long as full data is available, there will be fewer unknowns.
The "might happens" need not be a concern, leaving freedom to find ideal settings.

[jas32]

Unlike a lot of people in this forum I know very little about the science behind sleep apnea but there is one thing about fixed pressure CPAP that I think is a major shortcoming.

In 2011 my first sleep study indicated that I needed 7” fixed pressure to address my sleep apnea. I was given a fixed pressure machine set a 7”. Fast forward to 2018 (when I turned 65) I asked for a new CPAP machine, apparently Medicare will only approve it if I do another sleep study which I was so glad I did. Come to find out my pressure requirement is now at 15” (instead of 7”).

I can only conclude that for the past few years I was actually not receiving my required therapy. Now that I’m more educated compared to just the past year, I probably won’t fall into that situation again. However, for the 99% of CPAP users who use their CPAP as a “set and forget” fixed pressure appliance, I’m afraid they are in the same boat as I was in my first 7 years of therapy.

Guess I’m not sure which is worse, the shortcomings of APAP (as pointed out by Lefty) or a machine not delivering the proper required pressure?

[palerider]

Guess I’m not sure which is worse, the shortcomings of APAP (as pointed out by Lefty) or a machine not delivering the proper required pressure?

Just because jason imagines shortcomings doesn't mean they're valid points.

What you pointed out is the reason that I'm on APAP though, because I was feeling worse and worse, (and not monitoring my data when I was on fixed pressure like I should have been doing), and my AHI was just getting worse and worse, but of course, the CPAP can't do *anything* about that.

[Rubicon]

As long as full data is available, there will be fewer unknowns.
The "might happens" need not be a concern, leaving freedom to find ideal settings.

Best Answer Award.