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It's in the S7 shell. I don't fully understand the technology but the algorithm is better suited to treat CSA than tradition BiPAP STs. It cost about a $1,000 more than a BiPAP ST. The link:

http://resmed.com/portal/site/ResMedUS/ ... nPNum=null

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CPAPopedia Keywords Contained In This Post (Click For Definition): bipap, CSA

I think some one is pulling our collective legs here!.
The link to is empty, was that the intention ?

D

See Resmed Newsletter Edition 4 on this page:
http://resmed.com.au/portal/site/ResMed ... vgnReset=1

This machine takes advantage of adaptive servo ventilation to primarily treat Cheyne Stokes central apneas. Instead of the usual passive exhaust venting that happens in the mask, adaptive CO2 ventilation is actively orchestrated by a dedicated adaptive servo circuit in this machine. Higher retained CO2 on an as-needed basis is what staves off Cheyne Stokes central apneas, and apparently other central apnea sub-phenotypes as well.

This machine is all about fixing central apneas via calculated CO2 retention on an as-needed basis.

http://resmed.com.au/Newsletters/Static ... 0911r1.pdf

Aha - yes a very interesting article. This link I did find

DSM

Now what I got out of this is the release of a new Resmed machine - the AUTOSET CS 2

Here is a link to this 'new' machine (excuse me if this has already been posted ad-nauseum - I haven't seen it before ). The inside blower as shown actually appears to resemble an S8 fan unit.

https://www.designawards.com.au/ADA/03- ... 54/054.htm

Looks like it is in the VPAP III form factor (it takes the older 2i heated humidifier).

What is interesting to me is that this unit uses a 'dual impellor' design - how about that - 'A twin jet turbo Bilevel xPAP'

DSM

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CPAPopedia Keywords Contained In This Post (Click For Definition): resmed, humidifier

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CPAPopedia Keywords Contained In This Post (Click For Definition): resmed, humidifier

DSM, the link in the first post works for me, you may have to cut-and-paste the entire URL, I notice it "wraps". (or maybe it got fixed in the meantime).

-Ric

Ric,

He fixed the link. Cheers Doug

AH! my second guess. Kwoooool !

-r

dsm wrote: What is interesting to me is that this unit uses a 'dual impellor' design - how about that - 'A twin jet turbo Bilevel xPAP'

Yes, DSM. And dual-opposed servo controlled impellors at that. That extra servo driven impellor is dedicated for the purpose of achieving a rather precise adaptive exhaust venting. Pretty cool, huh?

I want one even though I most definitely don't need what is known in the respiratory world as adaptive-servo ventilation. .

-SWS wrote: This machine takes advantage of adaptive servo ventilation to primarily treat Cheyne Stokes central apneas. Instead of the usual passive exhaust venting that happens in the mask, adaptive CO2 ventilation is actively orchestrated by a dedicated adaptive servo circuit in this machine. Higher retained CO2 on an as-needed basis is what staves off Cheyne Stokes central apneas, and apparently other central apnea sub-phenotypes as well.

I should probably add to that by saying this adaptive-servo machine's primary central apnea benefit is currently for Cheyne Stokes central apneas because that sub-phenotype of central apnea is one of hypocapnic induction. The machine thus actively orchestrates the retention of CO2 in the ventilation delivery circuit so that a hypocapnic threshold of excessive CO2 depletion is not crossed.

Cheyne Stokes is probably one of the easiest central-apnea breathing patterns to algorithmically recognize. And this machine's servo-controlled kinetic retention of CO2 is a fairly easy algorithmic impeller response to administer. That is precisely why this machine's forte is currently that of addressing Cheyne Stokes central apneas. Other hypocapnic central apneas such as highly-patternistic CSDB central apneas may be treated via this same sequence of breathing pattern recognition and orchestration of CO2 retention.

However, some central apneas are hypercapnic instead of hypocapnic (as were the CSR and CSDB cases stated above). In some of those hypercapnic cases, advanced circuit depletion of expiratory CO2 theoretically just may fix some of those central apneas as well. Baselining, mathematical characterizing/modeling, and mathematical pattern recognition developments within this machine's algorithm may even eventually widen this machine's CO2-kinetic-based central-apnea applicability. In other words it's conceivable that this machine's central apnea "patient base" or "user base" may increase with algorithmic developments over the years.

Lastly, central apnea sub-phenotypes that are neither directly nor indirectly related to CO2 kinetics, very likely stand to gain no discernible benefits from these adaptive-servo ventilation techniques. Very interesting and promising technology none the less.

SWS, To restate the benefits & purpose in simple terms, I take it to be as follows ...

Impeller 2 use
- The exhale cycle is controlled to draw the exhaled breath back down the airtube at a rate the patient is comfortable with. The effect of this is that the 6 foot air tube will then be holding a predictable amount of CO2 at the end of an exhale cycle.

Impeller 1 use
On Inhale, the machine's main impeller because of its low inertia (light weight) can accelerate quickly (within current adjustment parameters for rise time etc:) to feed the held CO2 mixed air back to the patient. And do so at the usual CMS settings the patient may require.

The goal being to better control the CO2 retained by the patient as this plays an important role in healthy breathing.

IIRC, I have read articles that talk of the importance of maintaining some level of blood CO2 saturation & that this is almost as important as good blood O2 saturation.

Am I on the right track ?

Cheers

DSM

A question re this CS unit.

I am trying to figure out what that protrusion is to the right side of the unit.
I was wondering if it is an ancillary pressure line as the little port at the side looks like an extra air line nozzel ?

The design award write-up for this new version of the VPAP Adapt SV machine mentioned 'a single pressure sensing line that is proximal to the mask' but I can't figure if they mean they use the main air host to sense the pressure or they use a new hose with an integrated pressure sensing line that allows sensing proximal to (def nearest to) the mask.

If so it gets back to the issues that were discussed in a rather 'warm' debate that took place here some months back on why manufacturers did or didn't use pressure sensing air lines that sample at the mask.

Any comments ?


DSM

Yes, DSM. I think you're on the right track. Two diametrically pressure-opposed servo controlled impellers working together. One facilitates positive air pressure and the other facilitates negative air pressure. They can be used alternately or in tandem to achieve precise breathing resynchronization, very much like being able to turn on a dime. Think of being able to instantaneously add positive and negative pressure vectors together to achieve a highly precise and nearly instantaneous resultant pressure. Just can't accomplish that degree of near-instantaneous (let alone opposing-vector) precision in the world of single-impeller xPAP. And when the negative-pressure impeller circuit needs to facilitate active CO2 venting it will do so with active impeller precision versus typical passive exhaust venting in the mask. I'm pretty sure that port protrusion you see on the side of the machine would be the port for adaptive exhaust venting, DSM. Indeed, increased control of CO2 kinetics are exactly what the adaptive exhaust venting feature is all about. (see note below)

My posts above mention that this machine focuses primarily on what is known as CSR or Cheyne Stokes breathing patterns. The last time I read white papers regarding the AutoSet CS was perhaps two years ago. This machine has been very successfully used in Australia for CSR for a couple years now. At that point only CSR had been mathematically characterized and treated within the designed constraints of the AutoSet CS algorithm. However, a few minutes ago I carefully read the Resmed marketing sheet for this AutoSet CS and was pleasantly shocked to see that the machine is now purported to treat all forms of central apnea, with emphasis on CSR, CSDB, and mixed apneas. Mixed apneas, CSDB central apneas, and CSR central apneas are all sub-phenotypes of central apneas that generally respond well to CO2 correction.

This AutoSet CS has several algorithmically driven modalities of operation. For CSR, positive pressure support may or may not be beneficial depending on whether obstructive SDB events happen to also be present. Thus this machine can be set in a mode to treat CSR without PAP support or to treat CSR with PAP support. In that first case CSR periodic breathing and central apneas will be algorithmically addressed with two separate adaptive servo techniques. In that second case CSR periodic breathing, central apneas, and obstructive SDB events will be algorithmically addressed with three dedicated and corresponding adaptive servo ventilation techniques.

Essentially with two diametrically opposed servo-controlled impellers utilizing an active exhaust-venting circuit, you can accomplish various highly beneficial combinations of: 1) precise target ventilation (with or without a timed back up rate) toward breath resynchronization, 2) conventional positive air pressure support, and 3) increased control of CO2 kinetic retention and depletion. Those are merely the repertoire techniques, however. Algorithmic sub-phenotype pattern recognition and a designed machine response for each must exist within the AutoSet CS firmware. Apparently Resmed has added quite a bit of functionality to that firmware in the last two years (related to these additional central apnea sub-phenotypes). I'm impressed.

I need to keep up with my reading so I don't unnecessarily use the words "theoretical" and "theoretically" like I did in my previous posts in this thread. What was theoretically proposed as technically feasible two years ago in the world of adaptive-servo ventilation techniques, is now freshly-designed reality in the current AutoSet CS model. Unfortunately, I don't think I'm going to find the time in the near future for much technical "pleasure reading". In the last two years the AutoSet CS has certainly made very impressive advances in central apnea treatment!



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On edit: The first parapraph about directionally opposed impellers is highlighted as being fundamentally incorrect regarding the Resmed AutoSet CS2 design. Much thanks to DSM for bringing this fact to light! Wonderful and very helpful Aussie engineer that he is!
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-SWS wrote:
<snip>

My posts above mention that this machine focuses primarily on what is known as CSR or Cheyne Stokes breathing patterns. The last time I read white papers regarding the AutoSet CS was perhaps two years ago. This machine has been very successfully used in Australia for CSR for a couple years now. At that point only CSR had been mathematically characterized and treated within the designed constraints of the AutoSet CS algorithm. However, a few minutes ago I carefully read the Resmed marketing sheet for this AutoSet CS and was pleasantly shocked to see that the machine is now purported to treat all forms of central apnea, with emphasis on CSR, CSDB, and mixed apneas. Mixed apneas, CSDB central apneas, and CSR central apneas are all sub-phenotypes of central apneas that generally respond well to CO2 correction.

This AutoSet CS has several algorithmically driven modalities of operation. For CSR, positive pressure support may or may not be beneficial depending on whether obstructive SDB events happen to also be present. Thus this machine can be set in a mode to treat CSR without PAP support or to treat CSR with PAP support. In that first case CSR periodic breathing and central apneas will be algorithmically addressed with two separate adaptive servo techniques. In that second case CSR periodic breathing, central apneas, and obstructive SDB events will be algorithmically addressed with three dedicated and corresponding adaptive servo ventilation techniques.

<snip>

I too noticed their statement re treating all types of SDB and that set my imagination going ...


I wondered if ...

- Resmed's recent price & other activities were in advance of them making a major play with this new protected design & that they are pulling off another 'Sullivan Autoset-T' coup (allowing that Respironics had changed the industry somewhat with their original Bipaps and recent Bipap AUTO - up until this Resmed announcement it looked a bit as if Respironics had taken the lead in xPAP innovation)

- I can't find the pricing of this new machine so can't really tell if they are planning a shake-up in the market but based on the design award data it seems to me they have lowered manufacturing costs & product complexity substantially & that this unit will be a big price breakthrough.

The insides of this new model (vs the older Sullivan CS model) are remarkably similar to their S8 manufacturing techniques.

Re the little port - that could be a good explanation of it.

What do you make of the 'proximal' (to the mask) sampling of pressure ?

DSM

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dsm wrote: What do you make of the 'proximal' (to the mask) sampling of pressure ?

Well, in both cases the transducer is actually inside the machine. However, that narrow diameter tube leading from the mask to the transducer inside the machine, reminds me of the narrow diameter tubes leading from my doctor's stethoscope to his ears. In both cases cardiac-oscillation pulse pressure waves travel very nicely up that tube. Manufacturers that don't attempt to pick off cardiac-oscillation pulse pressure waves don't really have much incentive to pressure-sense at the mask with a narrow tube in my opinion. It's really not that expensive to put the narrow diameter tube in place if there's a genuine need for it.

Re: the Autoset CS machine potentially bolstering Resmed's market share. I'm not much of a market analyst, but that exact thought definitely crossed my mind too, DSM.