Questions for Respironics regarding their APAPs.

I have a meeting with my Respironics next Thursday rep to go over their algorithm for the Remstar Auot and BiPAP Auto. Please let me know if you have any questions you'd like answered and I'll post them here.

I'd like to know if they made any changes to the algorithm on the new "M" series Auto.

My biggest gripe is not getting ALL the manuals...but we have beat that to
death. I wish they could put it on their website. They currently have one
machine's clinician's manual on their website.

Maybe we could register on their site, agree to a release from liability and
be allowed to download all the manuals.

Measuring AHI.

IF the machine spends most of its time at Low pressure and since time is a part of the AHI average calculation. Is is probable that a low AHI at lower pressure is misleading since the large amount of time spent at the lower pressure reduces the average? (More events / More time = Lower AHI)

Conversely a higher AHI at higher pressures could be misleading since less time might be spent at the higher pressure but the AHI could be higher even if there are fewer events because of less time. (Less events/less time - Higher AHI)

The reason I'm asking is because my AHI "appears lowest at the lower pressures (5-6) and on my graph my AHI appears to rise as the pressure rises.

TO make it more weird, My HI drops almost to zero at 9cm but my OSA jumps up at 9 cm. They actually cross over HI drops and OSA skyrockets. I was titrated at 9cm. During my sleep study they got HI to zero at 9cm and only noted 2 OSA for the study and no centrals. I have a Respironics APAP and it shows increasing OSA (Centrals?-not likely) at 9cm and no NR-OSA's.

Is there anything to explain the divergence between HI & OSA?

In addition, when are flags tripped? If I show a flag when the machine is at low pressure and the machine raises pressure and then there are more flags at higher pressure then at low pressure does that mean that the higher pressure is creating events or would the events still be there even if the pressure didn't rise. (I realize this may be a catch-22).

Tnx,

Tom

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CPAPopedia Keywords Contained In This Post (Click For Definition): respironics, AHI, APAP

Would they document the data format of their smart cards?

Hi DME_Guy

I really appreciate you doing this. It is a good start for a number of reasons.

I have been reading my way thru the patent that DVL provided us a link to &
I started summarizing the points it makes but after a couple of hours put that aside.

There is a lot to work through.

One point I had been trying to determine from all the statements in the patent, was the nature of the AUTO as to if it was primarily designed as a 'defensive' mechanism in regard to OSA events or is it both 'defensive and offensive' mechanism in regards to OSA events.

I will try to clarify what I mean.

Among the early AUTOs (from when flow-based AUTOs were introduced) I have statements from Resmed that their AUTO worked to prevent OSA events but when the machine actually detected one (often a sudden OSA), they did not try to clear it but waited until the patient got over it then increased pressure to prevent the next one. Also they said they did not at all attempt to increase pressure at all if the a central apnea was detected.

The point re these early AUTOs was that they were 'defensive' & did not explicity go on the 'offensive' when an OSA was detected, that is, offensive in the sense of deliberately attacking & clearing OSA blockages.

I have read through the patent but still can't find any clear statement (not that it isn't there, I just can't find one yet) that clearly says this 2004 designed AUTO (from the date in the patent) does offensive work. What I am looking for is a clear statement about the machine being designed to both anticipate OSA events as well as trying to clear any single one that occurs.

I can find statements that could be interpreted as taking offensive action (such as the snore control unit requesting the pressure unit to increase CMS, which it can do by asking it to increase by 1cms in 15 seconds then lock that in for 1 minute, then repeat.

The patent data on the Apnea detection circuit is that it can request the pressure unit to increase CMS by 1 then lock that for 30 secs then repeat this for a maximum of 3 cms above the current pressure being delivered, then wait 8 mins. However if the current pressure being delivered is at 8 cms or lower the maximum the Apnea unit will be allowed to go to is set at 11 cms (see paras 150 & above in the patent application). Once maximum target has been reached if the Apnea unit requests further increase, they are actually turned into pressure decreases.

The above data from the patent is really helping to explain how one type of machine works but I am still keen to hear a manufacturer state in unambiguous terms, that their machine not only works defensively but with newer algorithms, will hunt down & clear any OSA event (a blockage). But the data in the patent document can be interpreted (as far as I can tell) as that the machine is being largely defensive but if in doing so if it clears an OSA (blockage) then that is a bonus (this issue being based on how long it takes the machine to respond to a blockage that might occur).

The question:

If we accept that the current AUTOs are designed to anticipate OSA events and respond to them (snores, flow limitations and OSA events). And that any AUTO is going to have a speed of reaction in responding to these events. Is their AUTO considered to be designed to and be capable of clearing a normal OSA blockage or is the actual and achievable goal to at best detect such an OSA blockage but in the expectation the machine's reaction is going to prevent the next one.

Stated in simpler terms ...
I guess I am looking to hear a manufacturer state clearly that their AUTOs have now become 'OSA blockage hunter killers' as well as OSA blockage defenders rather than just OSA blockage defenders as they have been, based on earlier pronouncements and developments.

Thanks

DSM

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

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

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

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

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

I'd like them to have an auto on for the humidifier.

Having a few levels of how aggressive it reacts like CFLEX does might work for some of us too.

Thanks very much for doing this!

They may have addressed this in their new series, but if not...

I wish the unit would make different sounds for "humidifier on" and "humidifier off" - maybe two-tone low-high for on and high-low for off, as many other kinds of equipment do to signify on/off.

Also, it would be nice to be able to select different alarm sounds, and perhaps have it increase in volume the longer it's going off. (And I'd sure like to know why mine often doesn't sound when my nasal pillow or mask has fallen off -- too many nights with less than full treatment!)

And for a time I was using the filters sold by cpap.com that go between the unit and the air hose, but when I checked how things were going with the software I found that the unit wasn't working correctly due to limited air flow. I wish the unit itself had an indication of the problem (without the software I wouldn't have known), and that the unit would work correctly with that filter in the line.

DME_Guy,
I do appreciate what you're doing, and don't want to rain on you parade, but:

What is this rep a representative of? A technical rep? A sales rep? It would be very very wonderful for this rep to give you some written data, of the technical kind, not just the PR stuff we simple users get to see on Respironics' web site.

I am leery of sales rep telling us things about their company's equipment.

And please, if at all possible have him demonstrate everything that can be demonstrated, on one of your machines.

Thanks.

O.

Thanks DME_guy,

Ask if the firmware on the RemStar AUTO w/ C-flex is "flash upgradable". I think mine is (at least) one dot.rev behind.

Also, my machine lags 10 minutes before it starts to accumulate usage data. For example, if I use the machine for 12 minutes, it records only 2 minutes. Anything less than 10 minutes "didn't happen". If I take a 5 minute break in the middle of the night, it "costs" me 15 minutes data, etc. Others have reported the same issue here on the forum, so I think it's a general problem. I wonder if that has been addressed/remedied in the newest release? (Hence my interest in question #1 above).

THANKS! .

-Ric

Ric,

I have asked that question before, and the reason is that most people take a few minutes to go to sleep. The machine wants asleep data to tell you what you are doing while asleep. Resmed has the exact same thing with their recording capability.

Once it starts recording, it will record the rest of the night, unless you get up to use the bathroom and shut the machine down, and then it starts over. This is a built in feature, not a defect.

Regards,

Titrator

Titrator wrote:This is a built in feature, not a defect.

Oh, that is so funny. .

No disrespect intended, Titrator. But that's exactly why those of us in the design realm kid around about built-in "design features". Did you hear that from a Respironics sales rep?

The thing that puts the lie to that answer is that the 10 minute gap doesn't always happen. It happens only about 50% of the time on my Remstar-auto, and when exactly it happens is unpredictable. If this were truly a designed in feature, then shouldn't it happen 100% of the time? Conversely, if it wasn't designed in, then it should never happen. Either way, there's a design flaw in the software. (I'm sure someone will take issue with that statement though.)

And then there's the nagging question of why does the machine record exactly two minutes of data preceding the ten minute gap?

And, if it was truly a design feature shouldn't all Respironics machines have the feature. My Respironics BiPAP-auto has never shown a 10 minute gap.

Of course, maybe if I talked long enough with a Respironics sales rep, he could convince me that it truly was a designed in feature. I served on a jury once where the plaintiff's attorney's argument was totally without merit, but day after day he kept repeating it as if it were true, and by the time we got to deliberations half the jury actually agreed with him. It took a couple of days for us to logically work through things enough that the rest of the jurors began to see the ridiculousness of the entire case.

Regards,
Bill

Nighthawkeye,

I am happy that I can amuse you. Experienced sleeptechs who have sleep apnea themselves don't always get a chance to do that with patients, unless we joke about the weather or the price of gas.

I haven't spoken to a Respironics Sales Rep in years. This topic of conversation came from Technical Support, which is a wonderful resource for DME Providers to learn about products.

I cannot speak to your individual issue with recording, I myself have not ogled over my own sleep data to that extent. I pretty much get a glance at my AHI and a quick look at pressures and then ask myself the most important question you can ask when using the software; How do I feel today? Did I sleep enough?

I can't help but ask if it makes a huge difference in treatment if you don't get the first 10 minutes or 2 minutes after the first 10 minutes? Again, I cannot substantiate your claim, because I don't follow data to that minute extent.

Though the data is great to look at and can be very useful when tracking progress, the best indicator is how you are feeling and a solid line of communication between you and your sleep physician.

Luckily while living in Kentucky, I have picked extremely competent sleep doctors and sleep labs. The good ones are out there and can be sought out.

I have told many a paper that in my area there is Dr Barbara Phillips and Dr Pamela Combs, both very good at what they do and pro APAP.

Regards,

Titrator

Titrator wrote:I cannot speak to your individual issue with recording, I myself have not ogled over my own sleep data to that extent. I pretty much get a glance at my AHI and a quick look at pressures and then ask myself the most important question you can ask when using the software; How do I feel today? Did I sleep enough?

Count yourself fortunate, Titrator. Actually, the reasons I do it are: 1. because if I don't download the oximeter data at least every other day, I lose data, and 2. because I have had a lot of issues to work through. Treatment has made quite a difference in my life, but it still is not where I'd like it to be. Downloading the data and looking over it is just a part of the daily routine, although sometimes, like this morning, after seeing that the oximeter data was pretty much level, I didn't bother to look at the Encore Pro data until just now when the window popped up asking if I wanted to delete the data. When I did look at it finally, it showed zero apneas. That doesn't happen very often, but it supports your argument that when treatment is effective, there's not only no need to look at the data, there's not much interest either.

Titrator wrote:I can't help but ask if it makes a huge difference in treatment if you dont get the first 10 minutes or 2 minutes after the first 10 minutes?

Nope, not now that I know it's just a glitch with the software. Before I knew that I was truly wondering if I was going into apnea right when I fell asleep without knowing about it. When you wake up feeling lousy in the morning and trying to understand why, errant data just adds to the confusion.

Titrator wrote:Though the data is great to look at and can be very usefull when traking progress, the best indicator is how you are feeling . . .

Agreed, but the only real reason for having the data to begin with is to help sort through and solve the problems. Erroneous data hampers this process.

Don't get me wrong, Titrator, I have benefitted immensely from using the Encore Pro software. I think it's great and recommend it highly, but using it has not been problem free. Fortunately, by being able to discuss it freely on this forum I've been able to distinguish between my own personal issues and machine issues.

BTW, here's a plot of one night demonstrating the randomness of the gap. One segment has the ten minute gap and two segments do not have the ten minute gap.



Regards,
Bill

If you guys don't mind, keep your post to questions only and only in regards as to how the alogrithm detects and responds to apneas, snores, flow limitations, and hyponpneas. And of course anything else I missed. What I need is a simple list of questions.

Example:

If the machine is set between 4 and 20, and the patient needs a pressure of 15 to prevent an apnea, how quickly will the machine repsond?

My main goal is get a good list of questions together that I can also ask the Resmed people and post up their answers here. I'd really like to know how each machine repsonds to events and what they respond to.

I am meeting with a sales rep but he's been in the business many years. If he can't answer a question we can get tech support on the phone.