ResMed VPAP Machine Family Tree

Rogelah,

SWS has just posted an absolutely spot on set of descriptions re the machines.

It is very easy to get confused between model names & features. Bilevels do come in such a variety of configurations but there aren't many SV machines on the market.
When comparing the Bipap SV & Vpap SV, it is easy to assume one machine can do what the other does, but that actually isn't so.

The Bipap SV (respironics) CAN run like a Bilevel S/T because it has lots of settings in the config menu that allow multiple modes (cpap, bipap s, bipap s/t, cpap + sv & bipap + sv modes).

The Vpap SV (Resmed) doesn't have settings that allow Bilevel S/T mode (only cpap, cpap + SV & SV modes).
I strongly suspect that this difference is a great source of confusion to everyone be they in the profession or not.

What SWS is politely saying is that there is a lot of confusion coming through from what you are reporting. It does appear that your advisors appear a tad confused.

Take care & make sure you understand what they are doing to you.

Good luck

DSM

rogelah wrote:

rogelah wrote:I know the Resmed Adapt SV is capable of bi-level ST...

-SWS wrote: Unlike the Respironics BiPAP AutoSV, The Resmed Adapt SV is not capable of BiLevel S/T mode. The Resmed Adapt SV will not allow you to set a manual backup rate or even a fixed PS value (that's the difference between IPAP and EPAP). That boils down to the Resmed Adapt SV machine not being able to run in ordinary BiLevel S/T mode or even BiLevel S mode.

I stand corrected. Thanks.

rogelah wrote:...and so is the Respironics Synchrony.

-SWS wrote: Well the Synchrony has been discontinued for some time here in the U.S. Respironics still sells a Synchrony model in Europe that is virtually identical to the AVAPS model sold here. Here they sell the Synchrony replacement as the "AVAPS" model. Leave the optional "volume assurance" feature turned off, and that AVAPS machine is functionally identical in every respect to the previous Synchrony model.

I'm pretty certain it was the "older" model; it didn't have AVAPS on it anywhere that I could see.

rogelah wrote:My brand of muscular dystrophy is being regarded as the same as ALS which gets more publicity and research; servo-ventilation is a touted as the answer for ALS.

=SWS wrote: Servo ventilation? I was very well aware of "pressure support" ventilation (ordinary BiLevel S/T) for that application, rogelah. That's RADICAL news to me that an SV machine's scant 3 or 4 minute flow-averaging can somehow amazingly manage to cope with any sustained downward ventilatory drive or trend---such as those presented by neuromuscular disease, including ALS.

Wrong modality. I meant to say bi-level S/T. Also I wasn't clear about being lumped in with ALS. ALS is usually a relatively terminal disease; FSHD is not. As such FSHD, gets short shrift as the ugly stepsister of ALS and is seldom regarded as serious.

-SWS wrote: ALS or amyotrophic lateral sclerosis is a chronic hypoventilation disease. And servo ventilation is not suitable for ALS or anything like it. Period. No disrespect to you, rogelah. I sincerely hope you're getting the details just as confused as I would under the circumstances. If your pulmo thinks servo ventilation is in any way shape or form suitable for ALS (or an ALS-like hypoventilation syndrome) then you need a machine-knowledgeable pulmo. I really apologize for saying it so bluntly.

Wrong is wrong. No apology needed. My intentions were good; my facts were wrong.

rogelah wrote:FSHD is not usually associated with ventilation problems. Although literature is sparse there is some which promote ventilation support testing for those of us who are wheelchair bound.

-SWS wrote:Well, it has always been conventional "pressure support" ventilation by the way of BiLevel S/T. I'm still surprised to hear a doctor prescribe servo ventilation for any of that. If he prescribed the Respironics brand of servo ventilation (the BiPAP AutoSV), you could at least run the machine in traditional BiLevel S/T mode, BiLevel S mode, or CPAP mode as a fall back. But if he prescribes the Resmed brand, you can only run SV mode or CPAP mode.

I have never spoken to either of the two sleep accredited doctors on the staff. Until I do I only have comments of the RTs and my pulmonologist to go by and my interpretation filtered through the summaries and non-professional research.

Rogelah, I think the discussions in this thread exemplify what this board collectively does well: we bounce our incredibly complex treatment details off each other. That, in turn, helps us collectively learn. But it also serves as an informal and sometimes important double-check of sorts, to make sure our treatment plans are not surprisingly way out in right field. Believe it or not, that happens from time to time. So we check up on each other.

Anyway, I am extremely impressed with how much you have managed to pick up in an inordinately short time. Truly amazing IMHO. I don't think I would have managed to pick up all those details under the same circumstances---especially now that I have a new frozen margarita machine to play with. Those buggers impair judgment...

So keep feeding us your details and we'll continue giving you our collective opinions. Don't feel the least bit bad about getting any of those myriad pulmonary and treatment details wrong at this extremely early stage of your research. Just bear in mind that we get things wrong on a regular basis as well, since most of us are not professionals. We may not always be in agreement on this message board, but when details seem very wrong you can expect some or even many of us to chime in with well-intended questions and comments.

We're here for you, my friend.

Thanks fellas. I wish I could blame it on lack of sleep or too many rum gimlets. No chance on rum gimlets; maybe it is lack of good sleep.

RT called, said he was ordering Adapt SV as the doctor prescribed. I said NO! I then asked to talk to the doctor and got the usual, "I'll have him call you." That being unacceptable I called patient relations and explained. She took my information and said she was going to walk to the pulmonary department. Forty-five minutes later the sleep doctor called.

He explained that my sleep study results had changed dramatically between the PSG and the BIPAP ST and that the VPAP ASV study had reduced the CSAs that were responsible for the high AHI in the BIPAP to zero. He wanted to continue the VPAP ASV study at home to get a better handle on the hypopneas and RERAs that remained high. He said the actual sleep study results were somewhat puzzling and he was trying to merge the data somehow to give him a better understanding.

We discussed the pros and cons of the use of the VPAP ASV vs BIPAP ST. He said BIPAP ST was equally a good modality to continue assessment at home. I felt better.

He also asked me to send him whatever information I had gleaned from the Internet so he could review it.

Good progress. Now to light a fire under the RT to get it ordered.

PS I ordered the sleep study results from medical records.

rogelah wrote: He explained that my sleep study results had changed dramatically between the PSG and the BIPAP ST and that the VPAP ASV study had reduced the CSAs that were responsible for the high AHI in the BIPAP to zero.

That part about eliminating the central apneas sounds excellent, rogelah. That would be the part servo-ventilation does very well: normalizing "short cycle" central dyscontrol via that rather narrow 3 or 4 minute flow-averaging target in the algorithm. That extremely short flow-targeting part of either servo-ventilation manufacturer's algorithm thus tends to do pretty well at normalizing and even eliminating central apneas and periodic breathing .

But unfortunately, that 3 or 4 minute method of flow-averaging inspiratory targets can do very poorly for a sustained downward force or trend in either ventilatory drive or neuromuscular respiratory effort---such as those presented by the various hypoventilatory conditions. And that algorithmic reality probably leaves you and your doctor struggling with precisely what you mentioned in the quote below:

rogelah wrote: He wanted to continue the VPAP ASV study at home to get a better handle on the hypopneas and RERAs that remained high. He said the actual sleep study results were somewhat puzzling and he was trying to merge the data somehow to give him a better understanding.

So here you just may be struggling with a more sustained hypoventilatory tendency that is neuromuscular-based. Servo ventilation's scant 3 or 4 minute flow-averaging method of devising a flow target just may repeatedly fall short---if that downward hypoventilatory force consistently outlasts or even partially skews those 3 or 4 minute flow-averaging windows. The end result of that short-sighted or lacking hypoventilatory assistance just may be sustained HI and perhaps even an excessive albeit disruptive counteractive neuromuscular respiratory effort (thus RERA's because of neuromuscular insufficiency that periodically requires neural vigilance with sleep disturbances to counteract).

So those two interrelated etiological components (the "short cycle" central dyscontrol manifesting as apneas and the more sustained neuromuscular hypoventilatory tendencies) are actually going to be at odds with SV's extremely narrow-window flow averaging and targeting. Here, we have that "short cycle" central dyscontrol (again manifesting as secondary central apneas) that fares well with SV's narrow 3 or 4 minute flow-targeting; but we also may have a recurring neuromuscular-based sustained hypoventilatory trend that will likely not be well-served by SV's extremely short flow-averaging and inspiratory targeting window.

So usually BiLevel S/T is employed for neuromuscular based hypoventilatory tendencies. Specifically larger PS values and shorter rise times together help ventilate----they help to mechanically offload some of the Work of Breathing (WOB). The BiLevel S/T will often help with secondary central dysregulation as well. However, if there's also an unlikely CompSAS component contributing here, then you and your doctor are conceivably struggling with multiple underlying etiologic components that can have competing or diametrically opposed pressure-treatment response patterns. In any case, you and your doctor are going to need to continue with that methodical trial-and-error to discover an optimum treatment protocol, rogelah.

rogelah wrote: We discussed the pros and cons of the use of the VPAP ASV vs BIPAP ST. He said BIPAP ST was equally a good modality to continue assessment at home.

Just a reminder that the Respiroinics BiPAP AutoSV machine will allow you and your doctor to experimentally/alternately run both AutoSV and BiLevel S/T modalities using the same machine and efficacy data set. The Resmed ASV design will not allow you to experimentally bail over to BiLevel S/T modality for comparison and possible improvement via that modality change.

Good luck to you and your doctors, rogelah! And a reminder that I am not a health professional.

http://www.resmed.com/assets/documents/ ... ow_eng.pdf

Ventilation to a moving target
To determine the degree of pressure support needed, the ASV
algorithm continuously calculates a target ventilation. Based on
respiratory rate and tidal volume, the target is 90% of the
patient’s recent average ventilation—that means that ventilation
can vary gradually and naturally over the course of the night.

My emphasis

Rogelah
In support of the added posts, the ability of the Bipap AutoSV to adjust risetime, seems to me to be a great tuning tool for working out what is best in your case.

The Vpap AdaptSV is very good at what it specifically targets, but has no (none) adjustment for risetime & I believe the designers did this because it simplified the whole SV mechanism, but I sure wish I could vary the rise time in my one. My complaint is that it is always very fast & creates mask leaks that can be hard to manage. The Vpap AdaptSV is known to be leak intolerant.

Because the Bipap AutoSV can be set up as a Bipap S/T it has all the adjustments needed to run it just like one. Such a choice gives your doctor a wider range of options.

Good luck.

DSM

ozij wrote:http://www.resmed.com/assets/documents/ ... ow_eng.pdf

Ventilation to a moving target
...the target is 90% of the patient’s recent average ventilation

Thanks for quoting that, ozij. That 90% target ventilation maintained by ASV is obviously more suitable for any given hyperventilatory type condition or response rather than a hypoventilatory one.

Please pardon some additional pontification about the ASV algorithm:
If ASV targeted 100% of any sustained downward trend in ventilatory response, that still amounts to hypoventilation that is uncorrected by the machine---potentially exacerbated by any given persistent hypoventilatory downward trend in physiology. However, because ASV targets 90% of that same hypoventilatory response, the ASV algorithm theoretically allows a natural downward hypoventilatory trend to occur in physiology---much more naturally and unchallenged than with a 100% recent-average flow target. In this particular algorithmic case, the ASV cannot even maintain ventilation at that previous less-severe rate of hypoventilation with that 90% target.

That moving 90% flow target can still correct or partially correct rogelah's central apneas, which fall well-below that 90% flow average in only a breath (albeit a latent and nearly missed breath). But the algorithm will probably under-correct a significant number of those central apneas, leaving central hypopneas instead---in the midst of any downward-skewed hypoventilatory flow-averaged target.

That last central-apnea under-correction problem can thus occur based in this compounded or twofold flow targeting problem: 1) ASV's moving flow-average can be downward skewed because of sustained or persistent hypoventilation, compounded by 2) that same low recent-average flow target being algorithmically reduced to a 90% figure.

So essentially, central apneas can be under-corrected or transformed to central hypopneas, and hypoventilation itself (sustained or erratic) conceivably goes unchallenged as well. That's why BiLevel S/T is the usual ticket for hypoventilatory type disorders. AVAPS is a BiLevel S/T machine model with an optional "volume assurance" feature thrown in (à la former Synchrony model).

If you want to experiment with servo-ventilation, then please consider the Respironic BiPAP AutoSV model which can be run as a BiLevel S/T machine as a fall back modality. Again, good luck!

A short recapitulation:

The main difference between the BIPAP titration and the PSG is that 154 hypopnea and 7 apneas in the PSG turned into 119 apneas on the BIPAP -- central and according to the doc, some hypopneas. The AHI was similar -- 67 BIPAP 61 PSG, and so was the lowest desat (74-75). The SV titration apparently resolved almost all apneas and left some -- we don't know how many -- hypopneas. Lowest desat this time around was 65.

Two doctors -- one met on or about June 8 and recently (the one on the phone) confirmed that the whole thing may be best treated with a volume focus.

Presumably the sleep doctor looked at all three studies, and presumably he knows you have diminished breathing capacity.
You, rogelah, have many links now to various machine and how they work. I hope you can discuss the machines with your doctor and show him those various descriptions.

If it were me I would want to understand:
What the doctor finds so confusing about my data?
How my diminished breathing capacity could effect the scoring of central vs. obstructive hypopneas (were both PSG and BIPAP titraton scored by the same persons? Why no mention of the apneas being central in the BIPAP titration report? Who scored the SV?)
I remember thinking kebsa (who has ms) would need an AVAPS -- but she turned out to need an SV -- and is doing better with the ResMed after having tried the Respironics.


O.

ozij wrote:A short recapitulation:

The main difference between the BIPAP titration and the PSG is that 154 hypopnea and 7 apneas in the PSG turned into 119 apneas on the BIPAP -- central and according to the doc, some hypopneas.

Thanks for that spot-on recapitulation, ozij. Neuromuscular disease can be inherently episodic regarding severity: those spurts or "clumps" rogelah referred to earlier in this thread. However, the above trend may very well reflect a CompSAS component, which may have been discernible during prior NPSG studies---specifically prior CPAP titration studies. The above differences may also represent significant week-to-week or even night-to-night variability in neurologically-based muscular dyscontrol I would think.

ozij wrote: I remember thinking kebsa (who has ms) would need an AVAPS -- but she turned out to need an SV -- and is doing better with the ResMed after having tried the Respironics.

Indeed, kebsa went through some fruitful trial-and-error. Unlike rogelah's less-than-stellar ASV results during the titration, kebsa's MS-related BiLevel therapy clicked as soon as her clinicians experimentally placed her on the Resmed ASV. Here are kebsa's comments about having received drastically different results from those two servo-ventilation machines to treat her MS-related Sleep Disordered Breathing (SDB):

kebsa wrote: the first machine i trialled actually made things worse not better despite it being a machine aimed at centrals- ir was a respironics, when i swapped to the resmed VPAP that i am still using i got great results instantly and the machine actually felt different to- obviously they algorithms in the 2 machines are very different and i wish i understood all this stuff well enough to work out why the difference- the DME techs i was sealing with said that some people with centrals did better with the respironics while others like me did bettter with the resmed which almost suggests that even with centrals the underlying reason for them may be rather different. mine are put down to neurological damage from MS but at least my results with this machine are fantastic!

viewtopic.php?f=1&t=42636&p=376506&#p376506

kebsa wrote: my initial AHI was 105 and my lowest oxygen saturation was 54%, i have lots of centrals and the basic structure of sleep has altered from the so called normal- my problems have been put down to mainly the effects of Multiple sclerosis, possibly some effect by medication and a small component of good old OSA

these days my AHI is 0.4, my AI is 0 and my sats above 95 all night, but it has taken a lot of juggling both settings and machines- finally swapping from the respironics adapt SV to the resmed vpap adapt sv and my results went from terrible to great so obviously the resmed algorithm is a better fit for me

viewtopic.php?f=1&t=41684&p=369147&#p369147

kebsa wrote: I can't help with a doctor for you but i can reinforce that the right machine can make a huge difference! i was diagnosed with complex sleep apnea and nerve damage from MS is considered to be the culprit. I was given a respironics auto SV for a trial but found no matter what they tried with the settings my AHI was still between 94 and 98- and oximeter showed that my oxygen sats were not dropping as much as without the machine (low 80's rathern than down to 50 without themachine) they cahnged me to the Resmed Vpap adapt SV and mu AHI dropped to 0.4 and AI of 0!!- the machines feel very different and they told me that some people do better with the resmed others do better with the repspironics

viewtopic.php?f=1&t=39426&p=345184&#p345184

Additional posts by kebsa:
search.php?keywords=resmed+respironics& ... mit=Search

When clinicians use Resmed Adapt SV to treat CompSAS comprised of more standard obstructive and central etiologic components, they specifically: 1) use a heightened EEP to address the upper-airway obstructive component, and 2) variable IPAP to address the central component on demand. Perhaps when neuromuscular hypoventilatory tendencies are complicated by CompSAS, a lower EEP may be necessary to effectively "bias" treatment with a higher PS value entailing lower expiratory WOB.

So in a more ordinary CompSAS etiology without a neuromuscular hypoventilatory component, Resmed ASV addresses the usual upper-airway obstructive component with a high enough fixed EEP; then variable IPAP rather dynamically addresses the variable central component. The underlined conjecture above speculates that a fixed "pressure-support bias" with lower-than-usual EEP might be necessary for hypoventilatory pressure-support assistance (the minimum PS value); then perhaps a higher fluctuating or maximum IPAP value can be used to dynamically address any CompSAS central component. In both cases, a fluctuating IPAP peak dynamically addresses a highly variable central component.

However, constant-value EEP strategy hypothetically differs in those two cases to uniquely address either constant need: 1) the fixed stenting objective of common upper-airway obstruction, versus 2) a much more consistent hypoventilatory pressure-support objective entailing lower expiratory WOB (thus a higher min PS value paired with lower EEP for more sustained ventilatory assistance).


Regardless, I think clinical trial-and-error can be indispensable when underlying SDB etiology is both uniquely complicated and not well understood by today's medicine.

An interesting exchange.

However, MS and FSHD (I can't comment on other types of neuromuscular disease) are not the same. MS is the body's own immune system attacking and damaging the myelin sheath that covers the brain and spine. Loss or damage to the myelin sheath prevents signals from transiting from the brain along the axons. The cause is unknown.

FSHD is caused by a genetic defect. It prevents formation of dystrophin, needed for building muscle.

MS is a failure of brain signals to reach their intended destination. FSHD results in muscle wasting.

As such, vis-a-vis sleep apnea, they may exhibit symptoms of sleep apnea that lead to conclusions whose treatment in ordinary sleep apnea cases is well known.

I haven't seen the output of each sleep study I've had yet but my focus has been to get them to also run tests to document respiratory insufficiency which is a more likely cause of my inability to get a good night's sleep: not wake up with a headache; get the sleep hours and still not feel rested. Things like a high PaCO2, a low vital capacity and oxygen desaturation.

BIPAP and BIPAP S/T are therapies generally prescribed for other types of MD. FSHD has not had the scrutiny given to DMD and ALS. FSHD does not usually present with ventilaion problems. However, it sometimes does.

I am determined to get the right therapy and help one more doctor to be more cognizant when it comes to FSHD.

Indeed, rogelah. I'm sure you have read the article below. This is for others who are following this thread:

http://www.mda.org/publications/Quest/q152sleep.html

Sleep apnea treatments and muscle disease

For the general population, continuous positive airway pressure, or CPAP, is the ventilation therapy commonly prescribed for obstructive apneas. CPAP blows in a continuous flow of air at a set pressure, keeping the airway from collapsing and obstructing breathing.

But for people whose problem is caused by weak respiratory muscles, bilevel positive airway pressure ventilation, typically called BiPAP, is more commonly used. (BiPAP is a registered trademark of Respironics.) Air is administered at a higher pressure level on inhalation and a lower (or zero) pressure on exhalation, so the patient doesn’t have to breathe out against pressure – something that’s difficult to do with weak respiratory muscles.

In muscle diseases, the BiPAP “span,” or difference between the inhalation and exhalation airflow pressures, is typically high to provide greater assistance to the inspiratory muscles and little or no resistance during exhalation.

Because ventilatory therapies for people with weak muscles are different than those used for obstructive apneas, it’s important that your physician is highly skilled at analyzing test results and knows which therapeutic solutions are appropriate for people with neuromuscular diseases.

Sleep studies valuable? ...

When respiratory muscle weakness causes nighttime breathing problems, it doesn’t take a polysomnogram to diagnose it, says John Bach, a physical medicine and rehabilitation specialist at University Hospital in Newark, N.J.

In patients with neuromuscular disease, Bach determines the need for ventilatory therapy by assessing symptoms and measuring exhaled carbon dioxide and vital capacity while the person is sitting and lying down. If those measurements don’t yield useful information in the clinic, he has patients do them at home overnight.

Patients showing signs of hypoventilation should be offered a trial of nocturnal ventilation, Bach advises, “and if they feel better using it, let them do so.”

Bach questions the usefulness of polysomnograms for people with muscle diseases because the test “interprets all abnormalities as central or obstructive apneas rather than muscle weakness,” he says — especially when read by physicians unfamiliar with neuromuscular disease.

This misdiagnosis then leads to improper treatment, he says.

And if straight CPAP is often NOT the correct solution for MD-based weak respiratory muscles, then that high EEP value during the ASV titration may be just as off base here as well.


So if your doctor and RT continue experimenting with ASV in an attempt to normalize central apneas, they just may need to adjust their EEP mindset from that of ordinary upper-airway obstruction to a neuromuscular-disease EEP paradigm that instead seeks to reduce your neuromuscular Work Of Breathing (WOB):

While recently speculating I wrote:When clinicians use Resmed Adapt SV to treat CompSAS comprised of more standard obstructive and central etiologic components, they specifically: 1) use a heightened EEP to address the upper-airway obstructive component, and 2) variable IPAP to address the central component on demand. Perhaps when neuromuscular hypoventilatory tendencies are complicated by CompSAS, a lower EEP may be necessary to effectively "bias" treatment with a higher PS value entailing lower expiratory WOB.

So in a more ordinary CompSAS etiology without a neuromuscular hypoventilatory component, Resmed ASV addresses the usual upper-airway obstructive component with a high enough fixed EEP; then variable IPAP rather dynamically addresses the variable central component. The underlined conjecture above speculates that a fixed "pressure-support bias" with lower-than-usual EEP might be necessary for hypoventilatory pressure-support assistance (the minimum PS value); then perhaps a higher fluctuating or maximum IPAP value can be used to dynamically address any CompSAS central component. In both cases, a fluctuating IPAP peak dynamically addresses a highly variable central component.

However, constant-value EEP strategy hypothetically differs in those two cases to uniquely address either constant need: 1) the fixed stenting objective of common upper-airway obstruction, versus 2) a much more consistent hypoventilatory pressure-support objective entailing lower expiratory WOB (thus a higher min PS value paired with lower EEP for more sustained ventilatory assistance).

Well, here is the bottom line:

He ordered the ResMed BiPAP ST. I'll find out Thursday when the machine is delivered what the settings are.

He rejected the Respironics AutoSV as being similar to the ResMed AdaptSV. I was clear about the Respironics also doing BIPAP S/T. For the time being I am going to chalk the rejection up to English not being his first language.

He read the article from Quest. He spoke to ResMed reps. He says my problem is not limited to NM hypoventilation based upon the PSGs and titrations.

He wants to bring me back in a couple of weeks, at no charge, for a reevaluation.

At this point I suspect lack of English is a problem. I am also suspicious of a possible linkage in the Lab to DME to ResMed triangle.

When I get the actual study outputs I will post them for the non-professionals to comment.

Well, the good doctor definitely needs to be in the driver's seat IMO. And there is still plenty of room for methodical trial-and-error here---especially if there is a prominent central or CompSAS component involved. I suspect they just may need to get that EEP or EPAP down to better accommodate your weakened respiratory muscles. But what the heck do I know?

We also have some health and sleep professionals who post here. So once you post your sleep study results, there may be sufficiently compelling data or information to get them involved in the analysis.

Haven't seen Muffy a.k.a. StillAnotherGuest, who manages a sleep center, in a while. If the ongoing information in your thread gets good and juicy, he may even decide to hop in with opinions as well.

Rogelah,

Just some thoughts recapping on posts made by SWS & Ozij.

The Vpap AdaptSV is a machine specifically targeted at forms of Periodic Breathing with the dominant form being Cheynes-Stokes Respiration & because of this target user, the machine also addresses therapy where the user has a large number of Central Apneas.

The SV methodology in this particular machine is to sample the breathing rate & volume (tidal flow) and to maintain a 3-minute window from which an averaged target volume (and also rate) is calculated & if the user deviates below 90% of the target the machine applies dynamic pressure support (breath-by-breath) until it has the user back on target. If the user's volume goes above the target the machine backs off pressure support and reverts to applying EEP (epap) & MinIpap.

SWS has spelled out several times that the above process specifically targets people with periodic breathing and also CAs. Periodic Breathing is a pattern & the pattern can have several causes but neuro-muscular breathing disorders don't usually feature in the list. This is where the concern here lies.

The Bipap AutoSV can be set up as a Bipap S/T which is a known therapy for neuro-muscular disorders. In more delicate cases the AVAPS feature of the Synchrony machine (or the AVAPS model as released in the USA) is an additional therapy approach as it adds an assured volume setting to the Bilevel S/T function. It does this when the RT sets a min assured volume in the machine which then monitors volume & if it starts to fall below the min will steadily adjust Ipap pressure in response so as to keep the user breathing to a desired min volume.

I believe SWS and Ozij (and myself) are saying that assured volume is far more likely to resolve complications arising from neuro-muscular problems, than applying Servo Ventilation which targets Periodic Breathing patterns.

I guess you need to ask yourself, do you believe your problem is one related to a Periodic Breathing pattern or is it from breathing difficulties triggered by a neuro-muscular disorder. The doctor seems unclear as to what he is addressing and you may be on target when you say you think the doc is being swayed by a sales rep selling a particular machine.

You really need to keep applying caution here.

Good luck

DSM