BiPap auto SV graphs - Help Please

[-SWS]

I'm pretty sure I posted a night pretty close to the edge of the distribution.

Your data shows significant night-to-night variation--- regarding residual PB. And both gradual variation and disruptive SDB episodes are not uncommon for some people with CompSAS.

CompSAS symptoms can be more of a long-trend moving target for PAP therapy to address than vanilla OSA. And that longitudinal variability is part of what can make CompSAS more difficult to treat. However, because CompSAS most often entails initial maladaptation to the machine---followed by at least some degree of long-term acclimation to that same machine---longitudinal or extended data trends in response to the machine are probably important. Those long-term data trends regarding CompSAS flareups and gradual moving trends are arguably more important than any single night of data IMO.

When I ask about seeing and reviewing data, why do they act as if I were a cigar smoking, parasol carrying dog? Does your sleep Dr discuss your data with you?

I never met my sleep doctor. And that may be because my very ordinary OSA and immediate successful CPAP results didn't leave much to discuss. However, my GP is an internist, and he has always been willing to discuss anything and everything about sleep or CPAP that I have ever placed on the table---including data. That cold response you received from your clinicians when trying to discuss your machine data is without question one of the most commonly reported anecdotes on this and other apnea message boards.

Titration then happens when you get a data-capable CPAP, take it home, and sleep with it for a week. Upon your return to the sleep dept. they download the data, set your prescription, and you are on your way. Since my titration was with the wrong machine, straight CPAP, my AHI went from a sleep study # of 35 to only 30.

How the sleep Dr knew enough to set my prescription to IPAP Max 20, Min 5, EPAP 5, Backup Rate: Auto, I don't know.

Well, once again your doctor blatantly ignored manufacturer recommendations for properly setting up patients on the BiPAP autoSV machine:

http://bipapautosv.respironics.com/faq.aspx

Question- Will the patient require an in-lab sleep study with our BiPAP autoSV in order to be placed on the device at home?

Answer- Yes. To treat the complexity of this patients as well as establish a baseline CPAP or BiPAP pressure for OSA, an in lab titration is necessary.

That important preliminary PSG objective, according to Respironics, is to find out exactly how much EPAP pressure is required to address the entire obstructive component. The BiPAP autoSV's obstructive-addressing EPAP pressure would be the same as CPAP pressure. But the key is that the respiratory effort belts employed in the PSG are required to differentiate the obstructive apneas and hypopneas from the central apneas and hypopneas. Your autoSV machine's EPAP setting is intended to address the obstructive event types according to Respironics. The central component of CompSAS will then be addressed by the machine's varying IPAP peak and an appropriate backup rate coupled with I time.

But if an initial PSG successfully differentiated all obstructive events from central events---and determined the correct pressure to address that obstructive CompSAS component---then a followup PSG titration on the autoSV is not necessary according to Respironics:

Question- Can an identified candidate w/ Complicated Breathing Patterns, Central, and/or Mixed Apneas or Periodic Breathing (CSR), be put on the device w/o coming into the sleep lab?

Answer- If the CPAP or BiPAP pressure is already determined in lab, the patient can be put directly on BiPAPautoSV. To assure that the patient is being properly treated it is a good idea to download the SmartCard data after 7-10 days.

However, your doctor once again blatantly ignores the Respironics recommendation by not bothering to look at your machine's data after 7-10 days to see if you still have outstanding CompSAS events requiring follow-up attention.

So in summary, for lack of that manufacturer-recommended PSG and followup SmartCard data, your doctor has absolutely no way of knowing: 1) if your outstanding hypopneas happen to be obstructive instead of central (possibly warranting increased EPAP and/or I rate adjustment), 2) that you currently have outstanding CompSAS events despite a best guess at autoSV settings, and 3) whether that PSG-lacking best guess amazingly lucked out as optimal autoSV settings---or just so happens to be suboptimal.


Did I mention that if it were me I would start shopping for a different in-network sleep doctor right about now?

[Kiralynx]

Mr. Capers,

Said I would get back to you, and then got side tracked (my mother is very ill).

You've probably already dug out what EPAP and IPAP are for, but in case you haven't, here is an explanation I posted some time ago.

viewtopic.php?p=359079#p359079

And just for a comparison, here are some "then and now" charts from me (with incorrect settings) and also from me with corrected settings.

viewtopic/t40856/viewtopic.php?p=357821#p357821

I think the thing which leaped out at me is that neither one of us was titrated on our ASVs. (At least, I don't think I was -- I'm still going round the mulberry bush trying to extract my full studies from the sleep center).

The other thing which leaped out at me was that like me, your EPAP and MinIPAP were set to the same thing, with your MaxIpap up there somewhere above them. In effect, although the ASV can be set with an EPAP and then a range of IPAP, they're setting it (I think, and hope someone will correct me if wrong) as if it were a regular auto cpap. And, it seems as if they may have made a mistake which we see commonly on this Forum -- too wide a range.

My own original pressures were set at 10, 10 and 14. I could not breathe out against the 10 EPAP, and it was causing apneas -- when my EPAP was lowered to 6, the apneas effectively vanished from my charts, since I had adequate pressure to address them. For that matter, many of the hypopneas also vanished (once I got the leak rates addressed) since the IPAP could roam between 10 and 14 as needed to handle them. Note: my average IPAP runs between 11 and 12, generally.)

Looking at your chart, and bearing in mind that this is one chart, it looks as if your EPAP is in fact, addressing the Apnea aspect of your situation. But clearly, the hypopnea aspect has not yet been addressed.

So I wonder, if you might be able to address the question with your doctor about setting your MinIPAP closer to your average IPAP, and keeping the MaxIPAP what it is currently set to. Although our ASVs are faster than ordinary autos, it still takes it time to go from a low setting like 5 up to 9 or higher if that is what is required, and that, it seems to me, leaves too much time for those pesky hypopneas to be occurring and making a hash of your sleep.

If your doctor isn't available, perhaps you could try the DME's respiratory therapist. I was, as I mentioned in the posts cited above, able to document arousals with apneas and pain issues with clusters of hypopneas through having the software and reading my own daily data. When I explained to the RT what my conclusions were, SHE discussed it with my doctor and got a revised prescription, then walked me through changing the pressures. I've been doing surprisingly well since that revision.

I am no specialist at this sort of thing, having been at this for less than a year, but perhaps this will give you something to consider, to research farther, and to discuss with your medical professionals.

[dsm]

Mr. Capers,


<snip>

So I wonder, if you might be able to address the question with your doctor about setting your MinIPAP closer to your average IPAP, and keeping the MaxIPAP what it is currently set to. Although our ASVs are faster than ordinary autos, it still takes it time to go from a low setting like 5 up to 9 or higher if that is what is required, and that, it seems to me, leaves too much time for those pesky hypopneas to be occurring and making a hash of your sleep.

<snip>

Kiralynx,

Just wanted to explore you comments "Although our ASVs are faster than ordinary autos, it takes time to go from a low setting lit 5 up to 9"

The Bipap AutoSV in SV mode (that is when MaxIPAP is set higher than MinIPAP) will raise pressure by up to 3 CMs within a single breath and can repeat that for 3 breaths in a row (unless it has reached MaxIPAP while attempting to do this).

An ordinary Auto machine would take minutes to raise pressure by 3 CMs & then it would back off for several minutes (again a lot depends on what the pressure was when it started out as it alters its approach as it increases past about 11 CMs).

Thus, A Bipap AutoSV could raise pressure by approx 9 CMs in 3 breaths - that is rocket fast. Autos by comparison are the tortoise (roughly 1 CMs per minute then pause if 3 CMs have been applied). But each is in a different race & thus not really comparable

DSM

[Kiralynx]

Thus, A Bipap AutoSV could raise pressure by approx 9 CMs in 3 breaths - that is rocket fast. Autos by comparison are the tortoise (roughly 1 CMs per minute then pause if 3 CMs have been applied). But each is in a different race & thus not really comparable

Agreed that a Bipap Auto SV can raise pressure by 9 cm in three breaths, if your figures are correct (I don't have time to verify). But in Mr. Capers' case, his MinIpap is 5 and his MaxIpap is 20. So it could take five breaths to go from Min to Max, and it seems to me that this would be plenty of time for hypopneas to occur.

As always, if you can reduce the reaction time, you can reduce the events, it seems to me.

[dsm]

Kiralynx,

I am not sure how many breaths it will try the 3 CMs increase but I suspect (vaguely recall reading it, possibly in the patent) that it will not try to exceed 10 CMs in any one incident. SWS may have info re this.

The key aspects of the SV mechanism are that it looks for PB in a 4 minute window of tracking & responds if the current breath is not going to reach 90% of the current peak volume target. The implication is that if the PB pattern is slower than 4 mins, then the Bipap AutoSV's target will move up or down in peak flow, with the pattern. Sudden peak flow breathing changes will certainly be addressed within the breath following a normal one. One central appearing quickly would fit into this category.

IMHO, this is a very effective machine as it has so many tunable settings & thus can be adpted when in the hands of a good therapist.

DSM

[-SWS]

The other thing which leaped out at me was that like me, your EPAP and MinIPAP were set to the same thing, with your MaxIpap up there somewhere above them. In effect, although the ASV can be set with an EPAP and then a range of IPAP, they're setting it (I think, and hope someone will correct me if wrong) as if it were a regular auto cpap.

The EPAP = IPAPmin setting on the autoSV machine is functionally very different than an ordinary auto CPAP, Kira.

An ordinary auto CPAP will fluctuate up and down---carrying the same inhale and exhale pressures---no matter how high or low those two bound-in-tandem breathing-phase pressures happen go. So the ventilatory "pressure support" or "PS" value is always zero in that case. If an auto CPAP happens to have an exhalation relief setting, then a small and constant "pressure support" or "PS" value may be incidentally introduced because of that expiratory and inspiratory pressure difference.

But unlike auto CPAP, Servo Ventilation is not about a constant or fixed "PS" value: the essence of Servo Ventilation is to fluctuate that "Pressure Support" on demand, per breath. The reason that Servo Ventilation fluctuates that PS is to straighten out or counteract those wildly varying flow amplitudes that are etiologically based in central dysregulation. However, some CompSAS patients tend to episodically destabilize a bit more easily with BiLevel compared to CPAP. For yet other patients, running the entire night in CPAP modality may bring on a few more CompSAS episodes than fixed BiLevel modality:
Bilevel Positive Airway Pressure Worsens Central Apneas During Sleep

-and-

"Minimizing Hypocapnia
The most critical component of any therapy for complex disease associated with CO2 dyscontrol is to minimize hypocapnia. Strategies include using the lowest pressure that allows reasonable control, avoiding modalities that destabilize (continuous and bilevel pressure may be less or more effective in individual patients; automatic continuous pressure machines should be avoided), the use of a nonvented mask, the use of enhanced expiratory rebreathing space, and controlled increases of CO2 concentrations in the inhaled air."

Anyway, the Respironics Servo Ventilation offering can optionally be applied on top of either fixed BiLevel modality or fixed CPAP modality. Whichever of those two fixed modalities just so happened to produce fewer destabilizing CompSAS events during the initial in-lab titration, will probably be the base modality upon which Servo Ventilation should first be attempted by the clinician. If a CompSAS patient just so happens to destabilize much less with fixed CPAP modality, for instance, then a knowledgeable clinician will first attempt to apply SV on top of that CPAP modality by setting IPAPmin at the same value as EPAP.

And yes, when that latter patient requires Servo Ventilation's on-demand IPAP peak fluctuations, they are suddenly employing BiLevel pressures to fix that CompSAS eruption. Paradoxical---kind of like benefiting from the hair of the very dog that bit them. But CompSAS pathophysiology seems to entail two separate states of control/dyscontrol with unique or separate phase-dependent mitigating requirements: 1) pre-eruption, where the most suitable (least disruptive) fixed modality should be employed, and 2) post-eruption, where SV's fluctuating IPAP peak is proportionally employed on demand.

Below we have an example of fluctuating SV being automatically applied to CPAP mode rather than BiLevel:


Once the amplitude variations in patient flow are straightened out, Servo Ventilation is automatically suspended in favor of CPAP modality (achieved by setting both EPAP and IPAPmin at the same pressure).

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

With all that said, Kira, what worked very well for you is worth highlighting so it doesn't get lost in our long-winded side discussion:

But clearly, the hypopnea aspect has not yet been addressed.

So I wonder, if you might be able to address the question with your doctor about setting your MinIPAP closer to your average IPAP, and keeping the MaxIPAP what it is currently set to. Although our ASVs are faster than ordinary autos, it still takes it time to go from a low setting like 5 up to 9 or higher if that is what is required, and that, it seems to me, leaves too much time for those pesky hypopneas to be occurring and making a hash of your sleep.

If your doctor isn't available, perhaps you could try the DME's respiratory therapist. I was, as I mentioned in the posts cited above, able to document arousals with apneas and pain issues with clusters of hypopneas through having the software and reading my own daily data. When I explained to the RT what my conclusions were, SHE discussed it with my doctor and got a revised prescription, then walked me through changing the pressures. I've been doing surprisingly well since that revision.

I am no specialist at this sort of thing, having been at this for less than a year, but perhaps this will give you something to consider, to research farther, and to discuss with your medical professionals.

So that trial-and-error method worked well for you. Kudos! But were your xPAP-scored outstanding hypopneas obstructive, central, or erratic hypoventilation? In that last case, central or obesity related types are etiological possibilities---and can probably yield hypopnea false-positives on a single data-channel xPAP machine. If the timeliness of stenting obstructive hypopneas is at issue, then raising EPAP can sometimes yield even better results than raising IPAP---since obstructive response time is preemptively obviated or reduced all the way to zero during each inspiratory phase. The other two scenarios tend to benefit from increasing "Pressure Support", thereby assisting with ventilation and/or Work of Breathing. A skilled PSG clinician would differentiate all those cases and adjust autoSV treatment accordingly.

Unfortunately a patient who cannot find a skilled clinician is not a rare patient on apnea message boards. So complicated collaborative patient threads like this are repeatedly born out of cold necessity. But the other side of that harsh-reality coin bears the repeated observation that some patients who genuinely need highly skilled clinicians don't always look hard enough. I think that's understandable, however, as SDB-impaired energy and cognition likely play a prominent role in many of those cases.


Good luck, Mr Capers, in finding optimal treatment!

[Mr Capers]

Hi to everyone who has responded. I've been off the board for a couple of days. It may be that there is life outside xPAP

I'm thinking that I may have inadvertently led us off on a merry chase through the woods. Here's is a proposal -

Let's start over. I'll post some spreadsheet data covering a good portion of my first couple of weeks. I'll also post a summary of the sleep study. You folks with a lot more experience than me, can call for me to post any day(s) of detail data for more thorough review based on your scan of the summary data.

I've been waiting for the system of me+BiPAP SV+mask(s) to stabilize. Thanks to SWS, I've had to put aside the Opus 360, which offered comfort but also leaked. Going to the Resmed Mirage Micro has been terrible. I have a groove down one side of my nose - right where my glasses sit - plus the feeling I've been 4-5 rounds with an experienced boxer. I've signed up for the nose bridge pad trial. I can't seem to get the equipment part of the system patted into place.

Data download took 45 minutes today. Such fragile software should be outlawed! I've used the Bill Gates' all-purpose solution - uninstall, shut-down, start-up, reinstall, try again, fail, do over until I'm If I had a voodoo doll for the card reader programmers, I would be out of pins to stick in it! I supervised programmers in two different jobs. No one got away with writing such junky code on my watch.

It may be a couple of days before I get this data posted. Please be patient. In the meantime, I suggest we all adjourn to another room, open a bottle of wine, and share some tapas.

Happy Naps,
Mr Capers

[-SWS]

I'm thinking that I may have inadvertently led us off on a merry chase through the woods. Here's is a proposal -

Let's start over.

What merry chase?

I'll summarize:

1) You want people to look at your data and suggest autoSV tweaks to treat your CompSAS better than your mum-lipped doctor can,
2) I suggest you get cooperative clinicians who know what they're doing and communicate what they're doing,
3) Kira suggested a very reasonable tweak to try.

Along the way we also discussed AutoSV theory and operation a bit. Our above input misses what objective, requiring adjournment and a fresh start?

There's not an abundance of Complex Sleep Apnea expertise to be had on any patient message board---with CompSAS/CSDB having been first brought out in medical literature in 2005. But bring out the data and we'll be glad to take a look...

[Mr Capers]

Hi,

A single night's data is hardly representative of a mass of data distributed over time. While there may be not much mass in two+weeks, it is a lot more than 1 night.

I'm not disregarding anyone's suggestions. I've copied long messages into a document for review when the welter of getting used to all this stuff is finally over.

I think your, and Kira's, and any other's, input might be more informed with a view of the entire territory rather than a snapshot of one night. Thus the statement that "I led us on a merry chase." My own situation was that I had finally struggled through the jungle of formating posts, and, victorious, was too eager to post a recent night's data...

I apologize to you, Kira, Dsm, and all the other good people who have responded. I needed to give you a better view of the entire situation rather than a snapshot of one night.

BTW, Giving up on my "mum sleep Doctor" is not in the cards - I'm gathering info for a discussion with a bit more information on my side. You have helped enormously.

Thank you,
Mr Capers

[-SWS]

Okay, Mr Capers. Bring that Encore data on at your leisure---and your sleep study data as well.

For all we know your practically-silent doctor may be a brilliant outside-the-box practitioner: he certainly practices faaaar outside the Respironics-recommended box.

Take your time and please be sure to ask plenty of questions. All that autoSV and CompSAS side-discussion above is only a small part of your crash course. We realize it will take you time to research and digest much of what has been said here. There is no such thing as a silly question on this message board.


P.S. Kira's suggested experimental tweak was a pretty darn good one IMO...

[Kiralynx]

IMHO, this is a very effective machine as it has so many tunable settings & thus can be adpted when in the hands of a good therapist.

DSM,

No arguments there. The problem, of course, is finding a good therapist who fully understands the parameters of the machine, AND the complex breathing patterns.

[Mr Capers]

Hi Everyone,

Under the topic: viewtopic/t44614/How-to-treat-this-Slee ... erapy.html, I've posted sleep study data and two weeks of summary data. Please let me know what detail you want.

Thanks for everything so far.

Mr Capers

[Kiralynx]

The EPAP = IPAPmin setting on the autoSV machine is functionally very different than an ordinary auto CPAP, Kira.

So I see from your explanation! Thank you -- that clarifies a few very muddy images. As I said, I am still reading and learning, and reformulating mental images....

Anyway, the Respironics Servo Ventilation offering can optionally be applied on top of either fixed BiLevel modality or fixed CPAP modality. Whichever of those two fixed modalities just so happened to produce fewer destabilizing CompSAS events during the initial in-lab titration, will probably be the base modality upon which Servo Ventilation should first be attempted by the clinician. If a CompSAS patient just so happens to destabilize much less with fixed CPAP modality, for instance, then a knowledgeable clinician will first attempt to apply SV on top of that CPAP modality by setting IPAPmin at the same value as EPAP.

That makes a certain amount of sense. It does seem, however, that if the patient in question already had a demonstrated need for a different EPAP and IPAP, that starting with EPAP = MinIpap could be counterproductive. But it would take a particularly skilled clinician to recognize this.

While recognizing that the people who come here are the ones for whom the standard procedures may not work, the evidence of this board regrettably appears to point to the skilled clinician as a rather rare bird.

And yes, when that latter patient requires Servo Ventilation's on-demand IPAP peak fluctuations, they are suddenly employing BiLevel pressures to fix that CompSAS eruption. Paradoxical---kind of like benefiting from the hair of the very dog that bit them. But CompSAS pathophysiology seems to entail two separate states of control/dyscontrol with unique or separate phase-dependent mitigating requirements: 1) pre-eruption, where the most suitable (least disruptive) fixed modality should be employed, and 2) post-eruption, where SV's fluctuating IPAP peak is proportionally employed on demand.

I think I'm going to have to read this a few more times, and then go study some of my own charts, and see if I can correlate a few things.

I can see how it would work with the image you posted, if the person tolerated straight CPAP in the first place, which I did not.

So that trial-and-error method worked well for you. Kudos! But were your xPAP-scored outstanding hypopneas obstructive, central, or erratic hypoventilation? In that last case, central or obesity related types are etiological possibilities---and can probably yield hypopnea false-positives on a single data-channel xPAP machine. If the timeliness of stenting obstructive hypopneas is at issue, then raising EPAP can sometimes yield even better results than raising IPAP---since obstructive response time is preemptively obviated or reduced all the way to zero during each inspiratory phase. The other two scenarios tend to benefit from increasing "Pressure Support", thereby assisting with ventilation and/or Work of Breathing. A skilled PSG clinician would differentiate all those cases and adjust autoSV treatment accordingly.

To the best of my knowledge, although I am still seriously overweight, I do not have obesity related hypoventilation -- my oncologist did blood gases prior to my surgery last year so she would know what she was dealing with for what she described as a "challenging" operation. (Hearing a surgeon whose expertise I respected say this, of course, did absolutely nothing for my unadulterated terror over the surgery.)

All I do know is that in my case, having the EPAP lower than MinIpap eliminated almost all apneas (I'll occasionally have one or two if I've had wine or hard cider with dinner) and most hypopneas. This seems to point to the notion that the apneas occurring once therapy started may have been central, since they vanished with the lowering of the EPAP.

One major difference between Mr. Capers and myself is the average tidal volume. I started out in the 300s and am now running in the lower 400s. His is in the upper 600s. Only time I've ever had one that high was when I wore my mask while dozing in a chair by my Mom's bedside. Interestingly, both of us had BPM rates in the 12s at the outset. (Mine now runs upper 14s and lower 15s)

Unfortunately a patient who cannot find a skilled clinician is not a rare patient on apnea message boards. So complicated collaborative patient threads like this are repeatedly born out of cold necessity. But the other side of that harsh-reality coin bears the repeated observation that some patients who genuinely need highly skilled clinicians don't always look hard enough. I think that's understandable, however, as SDB-impaired energy and cognition likely play a prominent role in many of those cases.

When your brain isn't working well, it's hard to battle insurance companies and medical practitioners who believe in one size fits all medicine. Of course, it's also entirely too easy to just be accept whatever the practitioner hands you. Especially if you're tired. The problem with this is that if it is a complicated situation, and the treatment is not optimal, you may end up not getting less tired.

BTW, as long as I have your attention, and since one of the recommendations to Mr. Capers is to get his leak rate within parameters for his mask, do you have any thoughts on the thread I started here

viewtopic.php?p=397867#p397867

on determining appropriate leak rate with a multi-level machine like the Bipap Auto SV?

Good luck, Mr Capers, in finding optimal treatment!

I'll second that.

[-SWS]

That makes a certain amount of sense. It does seem, however, that if the patient in question already had a demonstrated need for a different EPAP and IPAP, that starting with EPAP = MinIpap could be counterproductive.

I agree, Kira. Interestingly, the Respironcs titration guide would have CompSAS patients using SV applied on top of CPAP as the default base modality (not BiLevel):

http://global.respironics.com/UserGuide ... 042977.pdf

Page 2 of that manufacturer-recommended titration guide has every patient starting with an ordinary CPAP titration. And, of course, most patients with ordinary OSA are left with CPAP modality. But you can also see on that same page that Respironics has only a pair of criteria for demonstrating that need for BiLevel:

1) the patient cannot tolerate the current pressure increase,
-or-
2) the pressure reaches 13 cm H20.

That following page commences the separate autoSV titration. But note that Respironics would actually have quite a few patients receiving their autoSV titrations using CPAP as the base modality rather than BiLevel.

While recognizing that the people who come here are the ones for whom the standard procedures may not work, the evidence of this board regrettably appears to point to the skilled clinician as a rather rare bird.

Agreed. And on the flip side of that coin, standards and recommendations tend to work as a rule rather than the exception. So patients who did not receive standard care from their clinicians in the first place are probably going to have therapy problems in disproportionate numbers. And in all likelihood they are showing up on the patient message boards in disproportionate numbers as well.

BTW, as long as I have your attention, and since one of the recommendations to Mr. Capers is to get his leak rate within parameters for his mask, do you have any thoughts on the thread I started

Not a lot of thoughts, other than Encore is obviously reporting the wrong fixed leak rate during BiLevel. It might be best to think of that leak line more as if it were a handy reference for night-to-night comparison rather than any kind of accurate measurement----with smooth and low being faaaar better than bumpy and high.