Resmed VPAP S9 Auto Pressure settings

[jnk]

If I wanted to give a brain and nervous system that was having blood-gas-regulation issues the opportunity to get used to (non-ASV) bilevel PAP, I personally would tend to choose regular bilevel mode instead of autobilevel mode. I would make sure EPAP was high enough to prevent most obstructive apneas, and I would adjust IPAP on that machine for comfort mostly (as in, least amount of air swallowing), and then I would let it ride that way for a few weeks to give the body/brain time to adjust to something stable. But hey, that's just me. And I ain't no doc or pro of any sort.

[Slinky]

My understanding is that 4 cms or 5 cms is the most common successful Pressure Support setting.

My sleep doctor has supported my adjusting therapy settings on my own WITH THE CONSTANT REMINDER to make ONE change at a time (including changing to a different mask) for ONE WEEK at a time BEFORE making ANY OTHER change. His reasoning is that we don't sleep the same every night even at home in familiar surroundings.

[Riverlea]

Rested Gal:

No, the Doc didn't mention that at all. They want me to stay at the same pressures for another four to six weeks. The apneas are now recording entirely as centrals, but they (I also saw the Attending) aren't sure what sort of events the machine is actually reporting as centrals. The doc explained to me that the machine is raising the pressures with the events, and supposedly (according to Resmed) centrals should not be causing the kind of pressure swings they are seeing.

The one thing I didn't like hearing is that, if the centrals subside, they would like to consider raising the IPAP again, from 14 back to 15. I have only been able to tolerate the machine since I dropped that pressure. I don't understand why they want to do that - again, their thinking seems to be that they aren't convinced these are centrals. Thank goodness, I don't have any weight or health issues contributing to the condition. But this problem in itself is becoming a bear. Bottom line, I feel the treatment is working but the events, whatever they are, are waking me up often and I'm tired much of the time.

Fortunately I've gotten used to the machine, the mask, and the taping. I'm very ready for this to work!

What do you think? More patience? Thanks, Rested Gal -
Riverlea

[Riverlea]

A further question for y'all: why would a regular Bipap machine tend to be better for someone with centrals than an auto vpap such as mine?

[Pugsy]

why would a regular Bipap machine tend to be better for someone with centrals than an auto vpap such as mine?

IF, big IF...the pressure increases with IPAP maximum triggered centrals then using the BiPap in straight bilevel mode with fixed EPAP and IPAP would in theory reduce the risk of pressure induced centrals.

It wouldn't mean a different machine from what you are using. Just a different mode of operation available in the S9 ResMed VPAP Auto.
Using Auto mode with a very narrow limited range could give similar results.

If the centrals don't go away and are not related to therapy pressure (thus being able to be limited with pressure adjustments) and are in great enough numbers to be a problem, then a different type of machine (the ASV) might be another option.

In general anyone who is having only pressure induced centrals (not centrals from some other physical reason) can possibly have a problem with any auto adjusting pressure machine if the maximum is above the threshold for triggering centrals.
Most people with pressure induced centrals will do better with fixed pressures below the central triggering yet they still need a pressure high enough to prevent the obstructive events. Sometimes a very fine line to walk.

[jnk]

A further question for y'all: why would a regular Bipap machine tend to be better for someone with centrals than an auto vpap such as mine?

Your machine can be run as an autobilevel by using it in VAuto mode or can be used as a regular bilevel by using it in S mode or can be used as a CPAP in CPAP mode. In VAuto mode, the clinician sets a minimum EPAP and maximum IPAP to allow the machine to automatically titrate every night. In S mode, the clinician sets actual EPAP and actual IPAP. (PS, the difference between breathe-in pressure and breathe-out pressure, is a constant in either mode, with your machine.) Were I having your troubles, I might choose for myself, with doc permission, to use either S mode (with Easy-Breathe) until my body stopped having treatment-induced (also called "pressure-induced") centrals, or CPAP mode.

Don't worry yourself unnecessarily about any statements your team makes now about what they MAY try in the future, as far as IPAP, for example. Your circumstances may change with respect to the air-swallowing. Or if not, I am sure you and they will take into full consideration your air-swallowing troubles when choosing modes and pressures in the future. Sometimes 0.2 cm can make all the difference one way or the other, and that can be figured out with experimentation. Some have found that not eating within three or four hours of bedtime does a LOT to prevent overnight air-swallowing.

The main thing now is to give your body/brain a chance to figure out what's going on so that it has the opportunity to adjust to it so that your team can see if the centrals will subside with present forms of treatment. My (nonprofessional) understanding is that (non-ASV) auto modes are not always considered the very best modes for allowing pressure-induced centrals to subside. Some docs use regular bilevel (S-mode in your machine) or CPAP (CPAP mode in your machine) to give the patient time for the centrals to go away. If that doesn't happen, another type of machine, an ASV, may work better for preventing obstruction without inducing centrals, in the long run. I am not aware, however, of non-ASV type autobilevel as a mode of therapy (VAuto mode in your machine) being considered the most common way to deal with pressure-induced centrals.

Any information that you can post from your most recent diagnostic sleep test and/or most recent titration sleep test would be useful, especially photos of them (with any personal information or facility-identifying information blocked out, of course). Also useful might be any screen shots of ResScan results from several nights of sleep.

Here is some further reading on ASV as a mode of treatment for complex sleep apnea as compared to other modes: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3077348/

A key statement in that summary is this one: "Presently, it appears that CPAP, bilevel PAP, and ASV remain the mainstream approaches to treating CompSA in clinical settings. Because there are no large, randomized controlled trials as yet comparing these devices, practitioners are left to struggle, case by case, to best match the device to the underlying physiological abnormalities."

[rested gal]

They want me to stay at the same pressures for another four to six weeks. The apneas are now recording entirely as centrals, but they (I also saw the Attending) aren't sure what sort of events the machine is actually reporting as centrals. The doc explained to me that the machine is raising the pressures with the events, and supposedly (according to Resmed) centrals should not be causing the kind of pressure swings they are seeing.

----

What do you think? More patience?
Riverlea

Well, your doctor is advising one thing -- for you to keep using autotitrating bilevel mode for another month or more.

Pugsy, jnk, and I are saying "autotitrating" is probably not the best mode to be in if centrals are hitting in large numbers during therapy. We're suggesting plain CPAP mode or plain bilevel mode. But no "auto" at all. Or at the very most (if the doctor keeps insisting on autotitrating)...auto in such a tight range it would be almost like not using "auto" mode.
We aren't doctors, though.

Autotitrating (auto mode in cpap or auto mode in a bilevel) is probably not a good way to deal with CompSA/CSDB.

IF, big IF...the pressure increases with IPAP maximum triggered centrals then using the BiPap in straight bilevel mode with fixed EPAP and IPAP would in theory reduce the risk of pressure induced centrals.

It wouldn't mean a different machine from what you are using. Just a different mode of operation available in the S9 ResMed VPAP Auto.
Using Auto mode with a very narrow limited range could give similar results.

Were I having your troubles, I might choose for myself, with doc permission, to use either S mode (with Easy-Breathe) until my body stopped having treatment-induced (also called "pressure-induced") centrals, or CPAP mode.

So. You've got a dilemma. It's your decision. Perhaps talk about it some more to your doctor.

I know what I'd do. I'd turn off the auto mode before another night passed.
jnk politely said, "with doc permission." I wouldn't even ask permission. I'd just do it. But that's me.

[Riverlea]

Plain CPAP is very uncomfortable for me. I'm certainly interested in trying a straight bipap mode on my machine. I think I'd like to wait a few days, then give it a shot if the centrals aren't going down (before running it by my doc, actually). My question now is, how would my pressures: IPAP 14, SP 4, EPAP 7 translate into the straight BIPAP mode?

[jnk]

jnk politely said, "with doc permission." I wouldn't even ask permission. I'd just do it. But that's me.

Sometimes I try way too hard not to offend the lurker-docs, don't I?

If I had a cooperative doc, I would probably give him the opportunity to feel like he was giving me permission to do what I concluded was best for my own body; but, yes, I agree 100% with Rested Gal that, in my case, if he didn't agree with me, I, too, would still switch out of an auto mode, if centrals or mixed apneas were persisting.

Plain CPAP is very uncomfortable for me.

Your machine is capable of CPAP mode with EPR, which is almost as comfortable as true bilevel.

I'm certainly interested in trying a straight bipap mode on my machine. I think I'd like to wait a few days, then give it a shot if the centrals aren't going down (before running it by my doc, actually). My question now is, how would my pressures: IPAP 14, SP 4, EPAP 7 translate into the straight BIPAP mode?

The answer to that might depend on what your latest titration study found and what your latest several nights of results in ResScan show. Without that data, if it was me, I would choose S-mode with Easy-Breathe with EPAP at 10 and IPAP at 14. If that made me swallow air, I would back off on the IPAP. (As a very broad general rule of thumb, EPAP prevents obstructive apneas. IPAP prevents much of the rest.) I would keep backing off on IPAP all the way down to straight 10 cm CPAP before I chose to lower the EPAP, if my doc was unsure whether those scored centrals might actually be obstructive/mixed.

I am not giving medical advice or treatment recommendations. I am just saying what I might choose to do for me if I were in a similar situation, based on what limited info I think I understand about the situation.

[archangle]

A further question for y'all: why would a regular Bipap machine tend to be better for someone with centrals than an auto vpap such as mine?

When discussing VPAP, BiPAP, etc., remember,

BiPAP is Respironics trademark for bilevel.
VPAP is ResMed trademark for bilevel.

Bilevel is the generic term.

[Pugsy]

Plain CPAP is very uncomfortable for me. I'm certainly interested in trying a straight bipap mode on my machine. I think I'd like to wait a few days, then give it a shot if the centrals aren't going down (before running it by my doc, actually). My question now is, how would my pressures: IPAP 14, SP 4, EPAP 7 translate into the straight BIPAP mode?

I am currently experimenting with the very same machine you are using and I am playing with all the modes. Straight CPAP mode with the highest EPR available of 3 isn't nearly as comfortable as straight bilevel mode. Even CPAP of 10 with EPR of 3 which essentially gives me 10 IPAP and 7 EPAP feels different than the same setting in straight bilevel mode. Just feels easier in bilevel mode. Hard to put into words.

Without seeing your reports and having any sense of how much time you are spending at the various pressures it is hard to figure out where to set things at in straight bilevel mode. If present IPAP 14 is reached often you may need higher pressures for the obstructive component..so that equals a higher EPAP. On the other hand if you spend most of the night at the lower end of the range then the EPAP of 7 might be doing a satisfactory job with the obstructive component and no need for a huge EPAP increase.

If your AHI is predominately central in nature with very minimal obstructive component (and we assume the centrals are treatment induced) then one would think you have some wiggle room to reduce the pressure and not have a huge increase in the obstructive component.

I think you need to look at the reports to get an idea where the machine is spending its time. Pressure increases will be in response to the obstructive component. The machine sits by and twiddles it thumbs when the centrals occur. Since I am rather gutsy in my experiments if it were me I would drop IPAP to 12 and maybe put EPAP at 8 in straight bilevel mode...see what happens and then evaluate which way to go. It will be quite comfortable to breathe at those settings. All I would want to expect to learn would be...do the centrals decrease in number and do the obstructives increase in number...then decide next step.

Again ideally, a good look at several nights of pressure detailed graphs is the best way to try to figure out what to experiment with. We can't really come up with a straight bilevel pressure that is sort of equal to your auto bilevel settings...but to be honest, why would we want to? 15 centrals an hour isn't working so I wouldn't want to duplicate that.

Your choice on how you wish to proceed. Rested Gal, Jnk and myself have a lot more hours on these machines than you do and we are quite comfortable experimenting with various pressures and machine modes. Not that we know it all, because we sure don't, we are just comfortable taking control of things ourselves.
I can see where it would be a big step for you to change what your doctor has advised. You are new to all this and there is a huge learning curve. Then you have to add the the complicating factor of those pesky centrals. Makes it doubly confusing. So just because we would do it doesn't mean you should do it unless you understand and are comfortable with it yourself.

[jnk]

Pugsy's approach sounds very reasonable to me.

And Rested Gal, as usual, seemed to me to sum up the crux of the matter beautifully.

. . . Straight CPAP mode with the highest EPR available of 3 isn't nearly as comfortable as straight bilevel mode. . . .

Thanks for that.

Is the difference in the two modes in that machine as noticeable if you disable Easy-Breathe in S mode?

Just curious.

[Riverlea]

I'm in awe of your knowledge, folks. And I'm feeling my resistance to technology. But what I do have is the 4 page ResScan software report which the doctor printed out and gave to me yesterday. It only covers the last week, since I'd been having to change pressures. Is there a way I can scan this into a post here?

Just one thing: I notice some of you are referring to my centrals as "pressure induced". But the doc was specific and adamant that they are NOT that. She said that they are actually caused by the CO2/ O2 business I described earlier. My instinct tells me she's right in this.

[jnk]

. . . Is there a way I can scan this into a post here? . . . referring to my centrals as "pressure induced". But the doc was specific and adamant that they are NOT that. She said that they are actually caused by the CO2/ O2 business.

You can use a scanner or camera to copy the pages and then post them to a photo-storage site and then post links to them here.

I apologize that I tend to use older terminology to describe the development of, or the persistence of, central apneas after the initiation of positive airway pressure. But not everyone (yet) agrees that "complex sleep apnea syndrome" (CompSAS) is the best way to refer to the problem. Some old-timer docs are just stubborn that way. Some docs think of central apnea as either being related to obstructions and the treatment thereof, or not, but central sleep apnea nonetheless, either way. In that sense, the difference to them is only one of whether the problem was discovered independent of or in conjunction with the application of airway pressure. And then it either goes away or it doesn't, but obstruction has to be treated either way.

My understanding is that the "CO2 / O2 business," as you put it, is an explanation of a mechanism often involved in CompSAS and non-CompSAS-related central apneas. And I agree that the description "pressure-induced" isn't necessarily the best, since that wording implies "too much pressure" to some, or seems to imply that the pressure itself is the cause of the problem, when, in actuality, the proper application of pressure is often a way to help deal with the condition. And if the root cause is obstruction, application of pressure my solve the problem completely for some.

[Pugsy]

Just one thing: I notice some of you are referring to my centrals as "pressure induced". But the doc was specific and adamant that they are NOT that. She said that they are actually caused by the CO2/ O2 business I described earlier. My instinct tells me she's right in this.

As Jnk says "pressure induced" is perhaps not the ideal wording. Sometimes with some people there are pressures that will trigger centrals to occur for some reason so perhaps therapy induced would be better term.
In other words sometimes with some people centrals might be triggered with any pressure (even a small amount) or at perhaps at pressure above a certain threshold.

Our idea to limit IPAP would be to see if there is a threshold pressure where you don't have the centrals show up. If your centrals are going to crop up in these numbers and do not decrease with time (as I suspect your doctor is leaning towards) with therapy pressure, even a small amount of pressure or at pressures that are sub therapeutic for your obstructive component then you may need a different type of machine.

Firehope (the forum member thread I mentioned) was lucky. His centrals abated with a reduction in pressure and his obstructive components were still very well treated. His threshold was easily found.

At this point where you are at and with limits to what we know, all we can speculate on is perhaps your being lucky and also have that pressure threshold where above triggers the centrals and below does not trigger the centrals. In other words we are just offering what we would do if we were in your shoes. We would try the easiest way first before wanting to go the other machine route or spend weeks with an AHI of 16 and 15 of those being centrals.

Some people do see the centrals go away with no changes. Some people don't.