Resmed VPAP Adapt SV - for Central Sleep Apnea

[frequenseeker]

-SWS, I think the final report will represent the further investigations you mentioned.

RG, yes I certainly did like the little S8, I had it for awhile somewhere back there.

I noticed it was suggested earlier here that possibly it was the overventilation of the ASV that was causing my hypocapnia and hence the EERS. However I was given the EERS with the first cpap study before I had the later ASV titration study.
I did have good cognitive improvement when it was added to my daily therapy.
Here is an excerpt from that first study, I think it is still relevant:

She is unstable on BiPAP during unstable NREM sleep. This is her best indicator of instability. She has fairly substantial obstruction
in REM - will need 12+ cm of H2O for treatment. She has periodic
breathing during unable NREM on CPAP. Reasonable to tolereate if
the clinical response is OK. Arousals are vigorous for visually
subtle airflow obstruction.
So I would recommend CPAP=12 with NV mask and 50 EERS given that
she has not done well clinically with conventional therapy.

-SWS, your insertion of the comparison of the two machines was, as you noted, taken from another topic. I think the comments that accompanied it should also be reviewed here:

I don't know where they got that "Adaption phase 40 minutes" for AdaptSV, it takes a heckuva lot less time than that.

That mask recommendation thing is screwy too. AdaptSV has the options for 4 masks, and other masks could very well be quite acceptable. But I very seriously doubt that ANY ASV machine will work with interfaces with significant restrictions (like a pillows-type of deal).

And leaks? Adapt SV runs quite well in the face of leaks more than 24 LPM (and that must be in addition to Exhaust Rate, which has got to be 30-35 LPM anyway).

Yeah, lotta mode, pressure and rate options for BiPAP SV.

I'm thinking we're gonna need a head-to-head, looking specifically at the ability of each machine to address the other 's failure to manage-- and I'm talking patients, not events, because I'll bet that BiPAP SV will have the same difficulty with Wake/1 transitions and poor sleep efficiency (creating unstable baselines) that AdaptSV has.
SAG

[-SWS]

I don't know where they got that "Adaption phase 40 minutes" for AdaptSV, it takes a heckuva lot less time than that.

I think that comment was SAG's earlier observation, perhaps based on those first couple/few ASV patients SAG studied. (?)

I'm spouting off my own general adaption-phase thoughts here, and not ASV fact. But general feedback-based adaption phase, based on respiratory recent averaging, should be somewhat variable across the patent population. Two reasons come to mind: 1) diseased respiratory frequency, phase, and amplitude regularity can be highly variable, especially when untreated (I think central instability can be inherently "recent-average unfriendly", depending on underlying central disease pathology and severity), and 2) a pressure-based epidemiological response (to even adaptive ventilatory-assistance) should theoretically be broad or variable across that same population.

So I don't think this adaption phase rating of 40 minutes can be interpreted as a population-wide constant. SAG's anecdote of much shorter adaption-phase seems to support that conclusion as well.

But it does sound as if the ASV adaption phase (earlier referred to as "learn patient" routine) may have been that preliminary phase of ASV treatment that Frequen reported as being less comfortable. And I still have to wonder if the Swift (that always fails the "learn circuit" routine) just may have contributed to an ASV adaption phase that was less comfortable for Frequen.

Thanks for conveying all this information, Frequen. It is much appreciated. .

[christinequilts]

So I don't think this adaption phase rating of 40 minutes can be interpreted as a population-wide constant. SAG's anecdote of much shorter adaption-phase seems to support that conclusion as well.

That's my take too- it could take up to that long for adaption-phase if there is a lot unstable breathing due to onset centrals or wake/sleep transitions during the first 40 minutes, but that its not likely in most users. Even in my case, where on a split night PSG just prior to my Adapt titration where I had such severe periodic breathing and onset events I couldn't fall asleep long enough to have a truly scorable event, according to Medicare guidelines, without breathing support of BiPAP ST, the Adapt works fine from almost the moment I put it on each night. With BiPAP ST, transitioning from wake to sleep had always been difficult, which resulted in me needing to use higher doses of sleep medications previously, as I could get to 'sleep' somewhat okay, it was staying there long enough to get to stage 2 and beyond that was a problem early in the night. The rest of the night had its share of problems with severe periodic breathing, central events and other issues, which the Adapt has dealt with very well for me.

The only time I was able to replicate any 'uncomfortableness' during the adaption-phase was when I tried using a Swift mask, after running LC with a Vista, since the Swift is unable to pass LC on its own. I've trialled a lot of various masks from different companies, and as long as they could pass LC on their own, I never remember it feeling off during the initial 'adaptation-phase'.

Absolutely no disrespect to your doctor. But that first quoted answer about masks raises plenty of confusion in my own mind. There must have been some kind of disconnect between question and answer, to account for what seems like a bit of an illogical answer to me. The original question pertained to the Swift failing ASV's Learn Circuit, and whether there were any treatment ramifications for failing that impedance-based pressure calibration routine using the Swift.

Echoes a lot of my thoughts too. A mask 'working', as in the air blows through and the machine appears to be doing what its suppose to even though it can't pass LC on its own has nothing to do with mouth leaks. Since FQ obviously passed on my experience with the Swift vs Vista (or any other mask for that matter), and her BI doc seems to think leaks came into play, I'll emphasize I used it for less the 2 hours total and I was awake for almost 1 1/2 hours of that, with no possible mouth leaks- I am one of those strange people who can open their mouth while using xPAP and not have air rush out unless the pressure has drastically increased very quickly, as it can with the Adapt when it switches to backup mode when I have a central event and I'm in deep sleep. The half hour I did manage to fall asleep was not normal, restful 'Adapt' sleep, but more similar to pre-Adapt sleep with BiPAP ST. My average leak for the entire 2 hours was under 3-4 L/m; if anything, my leak rate with the Swift is lower then with other masks, though my leak rate is nearly always within the "Excellent" rating by the Adapt, so I don't believe leaks were the issue, which leaves the mask itself and its interplay with the Adapt.

So back to the VPAP III. I distinctly recall reading a few years ago when you first discovered using the VPAP III easily your own spontaneous breath rate hastened with nothing more than a higher experimental back up rate.

Her VPAP didn't have backup rate, it was a regular BiLevelPAP. I do recall she borrowed a VPAP III ST for a sort period of time at one point, but that her sleep doctor at the time would not script for one as she felt strongly BiPAP ST can cause problems if used when there are not centrals (or other non-SDB related respiratory issues). I think it was DSM you're remember who had problems with increase BPM when he experimented with using a VPAP III ST- I remember his description of becoming a supercharged cat very well (I have a couple fur balls that do that from time to time...especially if the one thinks she's being chased by a certain green vegetable-lol).

I'm the first to admit BiPAP ST is not the easiest thing to sleep with and that's why originally my doctor had me do a trial month before even getting insurance involved, with my original titration having such inconclusive results 3 1/2 years ago. His concern was that whatever benefit I gained from using BiPAP ST could be canceled out by the negative effects of using a BiPAP ST. Luckily it didn't turn out to be that way, as long as I avoided certain BiLevelPAP ST....I still don't want to think what would have happened to me if I hadn't been able to obtain some relief for all those years.

[frequenseeker]

Yes Christinequilts, you have my history with the ST trial correct.
That was an interesting description from DSM of the autonomic hyperactivity, like what I experienced in the study as well (extreme coldness, anxiety etc. that took awhile to settle down).

I think I want to say here that the feeling of discomfort I described in starting up ASV with the Swift ("learn patient") and that CQ has written about so articulately, has a chance of being related to my restrictive airway and/or lungs..

I usually would feel more comfortable after awhile, maybe 10 min, of breathing with it. It felt like parts of me inside needed to open up and when they did, the machine backed off. Like my turbinates were the problem, and maybe my ?asthma?emphysema, whatever is going on with my stiff lungs...

In reading CQ's description of her discomfort with the Swift/ASV, I am not sure we are talking about the same thing...

It may be that I like the Swift so much exactly because it works to open my turbinates (or some other airway part) therapeutically and allows a better pap result/experience therefore.

I know that even off pap, during the day, I feel like my turbinates are impeding flow. One of my docs looked at them once and said they looked swollen, offered Nasonex, but I didn't follow through with that one.

It may be yet another place where my edema is manifesting, or some other non allergic explanation. I have been running with chronically swollen neck lymph nodes it seems forever..After the last round of antibiotics, I had a spell of wonderful openness when I breathed in through the nose. Now am back into the extra swollen sinus infection type of impediment and back on the z-max as I was again knocked off my feet in relapse.

I think this is a point that warrants consideration. If my discomfort in starting up the ASV with the Swift is being looked at as evidence for the theory of it being wrong to use, my sinus/turbinates/lung condition really needs to be factored into the equation.

I live with it constantly so I don't really notice most of the time, but really as I look at it now it is a problem that I need to deal with. I know I had identified it last year as the reason I tend to swallow my food right down and not chew. It's because I can't breathe and chew at the same time...unless I really try hard. It is kinda interesting: I gravitate to soft foods like soup and oatmeal and bread and soft fish even though I really want to eat brown rice and salad and crunchy vegetables. This pattern has become really strong since starting pap, and very strong in the months since starting ASV. I think I am having a revelation here

Anyway, like I say, most of the time me and the machine would gradually settle in together, and I would feel like I was breathing through my nose much better then too, like something had opened up. And sleep fine until the dreaded wakeup with the spasms, etc that sent me in for the recent study, which I think originated from the fast backup rate and the lack of REM apnea prevention.

Just occasionally the machine would seem to run away from me in the middle of the night and if I did a LC with the Vista again it would be better thereafter. I wonder if it was interpreting my tight airway as a flow limitation to be overcome. I don't understand flow limitation in the apnea therapy lexicon fully, and it is not measured in the AutoScan, maybe someone can comment?

I have some screen shots from my sleep study I expect to be posting soon. The nasal air flow was pointed out as a parameter of significance, maybe it has a relationship to my issue explored above..

frequenseeker

[-SWS]

Hah!! So much for distinct memories on my part, when I really have apnea-fried brain cells! Alright. Thanks for clearing that one up.

Interesting comment from Frequen's earlier post about her medical staff presenting a variety of physiologic "challenges" to determine optimum treatment. Medical/physiology "challenges" always remind me of inanimate-world "black box" testing. Especially in this case, where underlying etiologies are unknown and combinational treatments are explored basically via patterns.

Very interesting to read about and discuss all of this!

[christinequilts]

Hah!! So much for distinct memories on my part, when I really have apnea-fried brain cells! Alright. Thanks for clearing that one up.

Just remember SWS, it can be worse...you can have a brain that can remember trivial details almost photographically, but can't remember to breath when I go to sleep.

I inherited my memory from my father, he was a Sargent in WWII and all his fellow Sargent's couldn't figure out how he could do early am roll calls without a flashlight to see his clipboard

Just don't ask me where my keys are...

[frequenseeker]

Not just any black box! Physiology is an extensive "testing ground" of myriad responses, checks and balances, the individualized and the species specific, and of course the unexpected and uncontrollable.. The etiologies are probably known enough to validate the problems encountered, but they cannot be fixed in isolation from each other.

Very hard to define it as a box at all, or any inanimate object really.
The concept may be of a structure that can (ultimately) defined, but, as you know, you can get it in place and it can work great and then one day...goes south if the system as a whole or in one part makes a shift.

My impression is that the respiration and gas balance mechanisms may be more finicky (okay, sensitive) than say the digestive tract which can endure extremes for years before we even become aware of it.

Yep, if the O2 or CO2 are off kilter even for a few minutes, we are down and out. Kidneys, brain, lungs, everything can get into the balancing act but the pap intervention is so targeted it creates its own challenge, that can only be assessed (accessed?) through interaction and management. Reading its signs, signals and yes patterns, is probably an art that is in its infancy.

[Lubman]

I have found the last couple of pages most interesting.
(1) Christine is right in that the adaptation phase doesn't take 40 minutes and that I too find that it is easier to fall asleep with the ASV than with a BiPap
or CPAP.

(2) I only noticed one time, after I traveled to a different altitude, that the algorithm seemed to be working faster than I was breathing -- in other words it would be changing before I had completed a breathing cycle.
Usually it gets in sync with your breathing in a relatively short order.

(3) ResMed's older style FF non vented mask, has an over the head strap and velcro in the back -- and no clips. Whereas the newer mask whose internet data sheet (as of late March 07) shows a mask that seems more suited for the home market.
It has clips just as the FF vented Mirage has and looks more like it.

I actually like the older style - as I think the across the head strap
actually fits better that the vented FFM(and potentially the newer NV).
Sure wished ResMed had kept the across the head strap with the newer
NV version. But they didn't ask me.


(4) I do notice some variation in the leak rates from night to night, and I wonder just how much the machine can compensate for leaks.
Any ideas on how the mask criteria is selected, because one can have excellent fit and still a leak rate of 40 L/min one night and 15L/m the next.

Perhaps the pressure sensor tube, now being farther away from the actual mask, due to the EERS tubing, isn't always on the mark??

(5) Is the consensus about the backup rate, that the machine only does 15 if it cannot get a good calculation based on the patients recent breathing rates?
e.g. if you are having lots of events or lengthy events, the machine after trying other variations of pressure and etc, simply reverts to the backup rate?


Lubman

[frequenseeker]

..the back-up rate of 15 is really a set parameter and can not be
modified. It is relevant across the night and will not let you breathe at a
lower rate. They designed it for CHF patients who on balance are tachypneic and breath faster than that. Future devices may allow us to modify that but in its current form no way to get the resp rate <15.

This is the word from the ResMed Medical Director via Dr. Gilmartin. Not a matter of consensus, apparently.
If someone else wants to contact ResMed and see if they get the same answer, that might be useful if verification is desired..

I will ask about the leak and the EERS. If it was a matter of the EERS, how would that explain the relatively large variations? Mouthleaks is what one doctor has suggested. Can you get a download and track where and when the leaks are occurring? That might shed some light on the subject.

It's interesting for me to review how each here refers to the IPAP coming in prematurely as the source of the discomfort issue being discussed. I actually like a little of that feeling when I am first hooked up. It is somehow reassuring to me, though admittedly it was a timing issue occasionally. It was more the resistance I felt to my passages "opening" to its pressure that was uncomfortable most times, as described in my previous post.
The fallout from the faster ventilation seemed to manifest in different ways.

frequenseeker

[christinequilts]

(2) I only noticed one time, after I traveled to a different altitude, that the algorithm seemed to be working faster than I was breathing -- in other words it would be changing before I had completed a breathing cycle.
Usually it gets in sync with your breathing in a relatively short order.

Did you run LC when you set up your machine at a different altitude? That's one of the changes that requires it being run, along with any changes in the circuit of course.

[dsm]

[quote="-SWS"]Frequenseeker, thanks for reporting in!

Absolutely no disrespect to your doctor. But that first quoted answer about masks raises plenty of confusion in my own mind. There must have been some kind of disconnect between question and answer, to account for what seems like a bit of an illogical answer to me. The original question pertained to the Swift failing ASV's Learn Circuit, and whether there were any treatment ramifications for failing that impedance-based pressure calibration routine using the Swift.

But I don't understand the answer relative to that question. It simply says there were limited ASV mask choices because the ASV algorithm is so leak sensitive. And since leaks through the mouth are bad to the ASV algorithm, a decision was made to go with a Full Face mask. Here's where I get really confused: Three of the four ASV mask choices on the menu are nasal only masks, right? So that's obviously not what your doctor was talking about.

But to continue my own perception of illogic relative to the ex-lunation. Those three nasal-only choices all pass the Learn Circuit routine on the ASV with flying colors. Yet the Swift cannot pass the Learn Circuit routine. But that sends us back to the original questions unanswered: What are the treatment ramifications, if any, of Learn Circuit failure with the Swift? And if there are no ramifications, then why is the calibration procedure that always fails with the Swift placed documented as a prominent step? Regardless, thank you very much for conveying the answer that you received, Frequen.

That second quote from the Resmed medical director gives a simple, clear, and extremely helpful answer IMO. The back up rate is fixed at 15. That answer is simple and it helps immensely IMO.

I have the above answer in bold, red text, because it's contrary to the impression I get reading the Resmed Fact sheet as well as the very promising marketing literature. But it looks like ASV entails at least two treatment characteristics that are not at all well-suited for you according to Resmed themselves: 1) fixed 15 BPM back up rate, and 2) EPAP Max of 10 cm.

So back to the VPAP III. I distinctly recall reading a few years ago when you first discovered using the VPAP III easily your own spontaneous breath rate hastened with nothing more than a higher experimental back up rate. Here we are once again with what seems to be RR skewing based either primarily or exclusively with a higher BR. It sounds as if you need more BR flexibility.

The Respironics BiPAP Auto SV marketing literature gives a feature rundown, compared side-by-side with the Resmed Adapt:


The above image was originally posted by SAG in this thread:
viewtopic.php?t=16527&highlight=asv+fixes

You can see this newly approved Respironics model has back up rate options as well as higher EPAP capability. Quite a few other bells and whistles too. Just don't know if it's your multi-issue PAP solution. Good luck! I'm way over due dropping you an email. Thanks again for the info, Frequen!

[-SWS]

Did you notice that the BipapSV doesn't appear to have a min PS. What that hints at is the algorithm is a modified (extended)Bipap Auto.

I interpret it very differently, Doug. When you see the following modalities listed, then the term "PS" takes on an implied functional difference relative to ventilatory flow (and not the pressure parameter itself): 1) CPAP, 2) CPAP + PS, 3) BiPAP, 4) BiPAP + PS.

PS, in this case, implicitly relates to more than just a difference between EPAP and IPAP pressure. To rhetorically drive the point a little further: what exactly are the differences among these four modalities? The key differences always lie in pressure-targeting versus flow-targeting on the system's output side.

In modality one (CPAP), for instance, we have pressure employed as the sole feedback and targeting mechanism. The set fixed pressure is thus delivered identically, for both respiratory cycles, throughout the night.

In modality two (CPAP + PS), we have a pressure-based fixed target (CPAP) upon which a flow-targeted oscillating pressure waveform is superimposed. That first component is a constant that is pressure-targeted. It provides a constant or static inflation of the airway, and thus tends to clear obstruction. However, that second component (PS) varies, on a per-breath basis, based on flow-targeting. Flow-targeting tends to support pressure-transitional ventilatory needs via this system's feedback loop.

In modality three, (BiPAP), we have a purely pressure-based feedback system going on, despite some degree of incidental flow-based ventilatory assistance. Incidental ventilatory assistance tends to occur here by virtue of pressure-target or based IPAP/EPAP transitions.

In modality four (BiPAP + PS), we have IPAP and EPAP fluctuating as a function of both pressure-based and flow-based feedback. If flow is on target, the machine will deliver that fixed IPAP and EPAP pressure throughout the night, without adding the flow-targeted PS component on a per-breath basis. When flow-targeted PS is added it is "automatically" or "adaptively" superimposed in addition to that fixed or set IPAP/EPAP.


Now let's look at that Respironics Auto BiPAP you mentioned, Doug. It has a PS parameter. However, that's where the PS similarity ends. The Respironics Auto BiPAP is a purely pressure-targeted machine, unlike the above two. That's what makes the Respironics Auto BiPAP machine a platform primarily for obstructive apnea patients and not central apnea patients, Doug, By contrast, the above two auto/adaptive ventilatory support type machines are in the same league regarding flow-based targeting capabilities, and thus central and CSR patients as the primary population target.

So Doug, it's worth separating patient-side sensor input (flow and pressure in all three modalities/machines discussed) from the primary target-based output of the system (flow or combinational targeted outputs for ventilatory assistance type modalities/machines and exclusively pressure-targeted output for obstruction oriented machines such as the Auto BiPAP, CPAP, and even APAP). Additionally, the two automatic/adaptive ventilatory support type machines discussed will modify delivery of each breath, if necessary, where the Auto BiPAP cannot and will not by design. Think of that Auto BiPAP as a traditional spontaneous BiPAP that gradually changes it's delivered IPAP and EPAP, versus adaptively modifying each breath (the latter of which those first two machines up for comparison are quite fuctionally capable by design). .

[Guest]

Anyone wondering if the Respironics claim of any mask but the Activa could be 'any mask except the Activa that has an O2 port/Luer lock connector on the mask itself for a sensor tube to connect to?' That would get around any mask with a smaller diameter lead tube...of course it would mean a lot less masks would be compatible too.

Marketing people are known for leaving out small, but critical details, or like ResMeds claim the Adapt would treat all forms of CSA, when it really meant it was FDA approved to treat all forms of CSA, just as all other BiPAP ST are approved to do the same? And when it comes to medical equipment, proving its effective is much different then drugs...they only have to be 'substantially equivalent', which is what ResMed claimed on its FDA application.

Just something that popped into my head recently...

[christinequilts]

First time I got guested in a long time...

[rested gal]

Good point about the need for a "plug in" place on a mask, for the sensor.

Marketing people are known for leaving out small, but critical details, or like ResMeds claim the Adapt would treat all forms of CSA

Yup.

Interesting that the Activa was singled out as a no-no. A shame, since it's probably the most non-leaky nasal mask to date.

Wonder if the Activa's not approved because something about the up/down pulsation of that mask on the face interferes with how the Adapt SV would sense air flow. A pantyhose strap around the front could put a stop to that!