resmed autoset vs. respironics mseris w/aflex

[jimid from destin]

Greetings,
I am new to this forum but would like to share my thoughts on these two machines i have used. I had the m-series and while it was effective in its purpose (ahi 1.5) I still was very conscious of always being on a machine, waking up many times a night albeit briefly.... I also woke up in the morning with a sensation of shallow breathing, something I felt uncomfortable with.....oh and with the pressure relief fr exhalation i could actually feel the three progressive stages of relief each breath.....and it made too much noise for my liking.

So, I purchased a resmed autoset II, for me this apap is far superior. I sleep deeper, not waking up at night, that shallow breathing thing ...it's gone, it's ahhhh so quiet, and i no longer feel I am on a machine. I can't feel the exhalation relief (i'm on highest setting 3) It al feels so natural. There does seem to be some trade off my ahi readings are higher 2.2 - 3.7.....here to further summarize...

M series with Aflex
Advantages
Easier to clean water tank
D/C converter included

Disadvantages
Ugly black box
Bulky
Noisier on inhalation
Could feel the pressure relief stages on exhalation
Limited information with out smart reader
Has bulky adapter to travel with
I felt I would shallow breath in the morning
Always conscious of being on a machine


Autoset II

Advantages
Smaller
Great to travel with the bag has appearance of a computer
Auto off
Breathe naturally never have sensation off being on machine
Sleep better, less movement, don’t wake up during the night,
feel more refreshed
more daily information available from machine without using card reader.
Water lasts longer in tank
Awesome quiet – can’t tell it is on
Adjustments can be made for length of hose and type of mask


Disadvantage
My ahi is higher 1.5 vs. 3.5
Have to buy a converter to use a battery
Once set to full face auto start will not work
Harder to clean water tank
Difficult to maneuver through different menus

I hope this may help someone.

[Slinky]

Due to the Resmed algorhythm, which DSM, SnoreDog or a few others can better explain if you want the technical info, they tend to score hypopneas a little higher than the Respironics, and if I remember correctly, the other brands as well. So take a look at your Resmed AIs and compare them to the Respironics AIs and see if there is any difference of consequence.

[Wulfman]

What are your pressure settings? What was your titrated pressure?
If your pressure needs for treating apneas is higher than 10 cm., you've also got the wrong machine.

Den

[AuntieNae]

Wolfman, please explain .. how is that the wrong machine if your pressure needs are greater than 10.

[Wulfman]

Wolfman, please explain .. how is that the wrong machine if your pressure needs are greater than 10.

The A10 algorithm in the ResMed Autos will not respond to apneas above the pressure of 10 cm......hence the name "A10" for the algorithm. ResMed was cautious in their design by not wanting to induce Central Apneas.....which can occur more often above the pressure of 10 cm. Some people are susceptible to them, but the vast majority are not. ResMed was looking at the smaller percentage in this case.
Respironics has its own method of avoiding Centrals. If, after three pressure increases, the apnea isn't cleared, the machine drops the pressure.

Den

[jnk]

Since ResMed's do raise pressure to chase the flow limitations and the snore that precede apneas that occur higher than 10, I feel strongly that statements implying that ResMeds don't treat apneas higher than 10 are very misleading.

After all, by that sort of reasoning, one could similarly make the statement that the Respironics algorithm doesn't respond to apneas or hypopneas at all, since it doesn't respond to an isolated apnea or hypononea, or the first one in a cluster, at any pressure, above or below 10, as was explained in the third post in this thread:

viewtopic.php?f=1&t=35298

[Wulfman]

ResMed Autos won't respond to the "out of nowhere", sudden, "frank" apneas above 10 cm. For them to actually respond to an apnea above 10 cm., the would have to be preceded by flow limitations or snores.
How many apneas are actually preceded by snores and flow limitations as compared to frank apneas would be the determination as to whether the ResMed Auto would work for them. Snores and flow limitations don't necessarily mean that an apnea is going to take place. And, an apnea can take place without being preceded by FLs and snores.

I know in my own particular case......damn few apneas are preceded by FLs and snores. I have very few apneas (above 10 cm.) in the first place and the ones that I do have aren't necessarily preceded by snores or flow limitations. In my trials with my auto, it chased snores and leaks.....and the apneas (and other events) occurred anyway. In my experience, the Autos aren't fast enough to respond to preempt/prevent any of MY events. If I set the minimum pressure to be where it needs to be to eliminate these events, I might as well chose a fixed pressure, because the sleep disturbance from pressure changes ain't worth it.


Den

[ozij]

You can read more about The Resmed Autoset Algorithm by Resmed here.

And the A10 rule is decribed here:
http://www.talkaboutsleep.com/sleep-dis ... itchat.htm.

The AutoSet algorithm responds in the same way in each of ResMed's AutoSet devices - pressure is increased in response to the degree of flattening present.

The autoset algorithm is still there in the version 8 machines (Resmed confirmed it writing to forum member dsm).
The A10 algorithm is part of the Autoset alrogrithm.

The A10 algorithm increases pressure in response to Flow Limitation, Snore, and Apnea up to 10cm H2O. Above 10cm H2O, pressure response to Flow Limitation and Snore continues, but there is no response to Apnea. AutoSet Spirit and AutoSet T do not differentiate between obstructive and central apneas. Increasing pressures above 10cm H2O in response to apnea can lead to "runaway" central apneas.

The Resmed algorithm will raise the pressure in response to flow limitations and snores no matter at what pressure they occur.
The Resmed will not raise the pressure to an apnea if that apnea occurs above a pressure of 10.
The Resmed, as we have all seen again and again, will consider more breathing variations as flow limited (or "hypopneas" )worthy of responding to than will other machines. Its response to flow limitations is actually very quick and aggressive.

Those three facts, put together mean the following:
If you don't snore or have flow limitations at more than 10, you can't trust the Resmed's automatic function to raise its pressure when you have an apnea above 10. If you don't snore or have flow limitation (hypopneas fall into the flow limitation category) the minimum pressure you have set above 10 will stay your minimum.
However, many people don't really fit into that "perfect breathing sudden apnea" category.

jimid from destin, Congratulations on finding the machine that is right for you, helps you sleep well at night, and (hopefully) feel better during the day. A Resmed's AHI is not equivalent to a Respironcs' - and should not be used to compare the quality of therapy given by the machine.

Resmed's 8 II series added a new way for delivering the pressure - which included a new, quieter motor, and different shape for the wave of air delivered to the patient - many people have responded to that like you have, jimid. The Autoset algorithm - the part that analyses a person's breathing pattern and says: "Whoa there! now is the time to raise the pressure" is still the same.

O.
Edited May 2009 to correct link - Resmed have changed their sites and all older links default to the home page....

[jnk]

I can see that autos don't work for everyone. And I can see that one brand might be better than another brand for a particular person. But I think that it is silly every time autos come up that the limitations of one brand's algorithm come up repeatedly while the limitations of other brands' autos are ignored. Because none of them are perfect. I think both ResMed and Respironics have improvements to make. That is the spirit behind the rest of this post, although I do use a ResMed Auto. That's my bias disclosure.

I agree with the statement that ResMed Autos won't respond to the out-of-nowhere, sudden, frank apneas above 10 cm. But isn't that also true of Respironics Autos? And if so, wouldn't it be nice if whenever someone states that "ResMeds dont' respond to an apnea above 10 cm. unless preceded by snore and flow limitation" that, for the sake of consistency, they also state that "Respironics Autos won't respond to an apnea at any pressure unless it is preceded by an apnea," if that is the case?

Or do I misunderstand what I read in the other thread, linked in my previous post in this thread?

As for the statement, "How many apneas are actually preceded by snores and flow limitations as compared to frank apneas would be the determination as to whether the ResMed Auto would work for them," couldn't the statement also be made, "How many apneas are actually preceded by other apneas would be the determination as to whether the Respironics Auto would work from them"?

Or do I misunderstand?

I "get" that snore and flow limitations don't necessarily mean that an apnea is going to take place. And I "get" that an apnea can take place without being preceded by FLs and snores. But wouldn't it also be true that an apnea doesn't necessarily mean that another apnea is going to take place, and that an apnea can take place without being preceded by another apnea?

Or do I misunderstand?

I could be completely wrong about all of that. (It wouldn't be the first time I've been wrong and it won't be the last. ) But I know myself well enough to know that I am likely to keep repeating the above misunderstanding every time I see the "10 cm apnea" rule being quoted about ResMeds until someone convinces me I'm wrong. So let's just assume my reasoning is wrong so that someone, if he or she has the time, can please explain to me how wrong I am, just as a personal favor to me and as a preemptive favor for the rest of the forum.

My post seems in line with the discussion in this thread, but would it be more polite if I started another? I don't know.

[Wulfman]

I can see that autos don't work for everyone. And I can see that one brand might be better than another brand for a particular person. But I think that it is silly every time autos come up that the limitations of one brand's algorithm come up repeatedly while the limitations of other brands' autos are ignored. Because none of them are perfect. I think both ResMed and Respironics have improvements to make. That is the spirit behind the rest of this post, although I do use a ResMed Auto. That's my bias disclosure.

I agree with the statement that ResMed Autos won't respond to the out-of-nowhere, sudden, frank apneas above 10 cm. But isn't that also true of Respironics Autos? And if so, wouldn't it be nice if whenever someone states that "ResMeds dont' respond to an apnea above 10 cm. unless preceded by snore and flow limitation" that, for the sake of consistency, they also state that "Respironics Autos won't respond to an apnea at any pressure unless it is preceded by an apnea," if that is the case?

Or do I misunderstand what I read in the other thread, linked in my previous post in this thread?

As for the statement, "How many apneas are actually preceded by snores and flow limitations as compared to frank apneas would be the determination as to whether the ResMed Auto would work for them," couldn't the statement could also be made, "How many apneas are actually preceded by other apneas would be the determination as to whether the Respironics Auto would work from them"?

Or do I misunderstand?

I "get" that snore and flow limitations don't necessarily mean that an apnea is going to take place. And I "get" that an apnea can take place without being preceded by FLs and snores. But wouldn't it also be true that an apnea doesn't necessarily mean that another apnea is going to take place, and that an apnea can take place without being preceded by another apnea?

Or do I misunderstand?

I could be completely wrong about all of that. (It wouldn't be the first time. ) But I know myself well enough to know that I am likely to keep repeating the above misunderstanding every time I see the "10 cm apnea" rule being quoted about ResMeds until someone convinces me I'm wrong. So let's just assume my reasoning is wrong so that someone, if they have the time, can please explain to me how wrong I am, just as a personal favor to me and as a preemptive favor for the rest of the forum.

My post seems in line with the discussion in this thread, but would it be more polite if I started another? I don't know.

You'll get no argument from ME. This is why I'm not particularly fond of "Autos" for treating this condition on a regular basis. Not only do they not all work the same, far too many people (doctors included) think that they "automatically" adjust to stop events.....which is far from the truth. And, with new users, problems with snoring and leaks can drive Autos crazy and end up wrecking a person's sleep. Plus, they come to the forums and are either told or get the impression that they NEED to get an "Auto" to adequately treat SA and/or come to believe that Autos are the only machines that collect sleep data.

< stepping off soapbox >

Den

[AuntieNae]

I appreciate reading everyone's comments on these two particular models.

My DME just switched me to the ResMed AutoSet 2 from the M Series Auto. I do have a back up M Series Auto I purchased outright so I can still "play" in both worlds. Since it has only been 1 night on the ResMed, I can not comment beyond saying it was a much quieter unit. I am learning how to set up the data display this morning after finding out it was not on.

[jnk]

You'll get no argument from ME. This is why I'm not particularly fond of "Autos" for treating this condition on a regular basis. Not only do they not all work the same, far too many people (doctors included) think that they "automatically" adjust to stop events.....which is far from the truth. And, with new users, problems with snoring and leaks can drive Autos crazy and end up wrecking a person's sleep. Plus, they come to the forums and are either told or get the impression that they NEED to get an "Auto" to adequately treat SA and/or come to believe that Autos are the only machines that collect sleep data.

< stepping off soapbox >

Den

Thanks for stepping onto the soapbox for a moment, Den. That helps.

And I agree 100%. I have had to limit strictly the range on my auto for those very reasons. Wouldn't have known to do that without you and others in this forum teaching me the importance of watching the data. The data is the prime thing.

Maybe one day autos will work more closely to how they are advertised. But, meantime, I'm not holding my breath. Not if I can help it anyway.

[ozij]

I can see that autos don't work for everyone. And I can see that one brand might be better than another brand for a particular person. But I think that it is silly every time autos come up that the limitations of one brand's algorithm come up repeatedly while the limitations of other brands' autos are ignored. Because none of them are perfect. I think both ResMed and Respironics have improvements to make. That is the spirit behind the rest of this post, although I do use a ResMed Auto. That's my bias disclosure.

I agree with the statement that ResMed Autos won't respond to the out-of-nowhere, sudden, frank apneas above 10 cm. But isn't that also true of Respironics Autos? And if so, wouldn't it be nice if whenever someone states that "ResMeds dont' respond to an apnea above 10 cm. unless preceded by snore and flow limitation" that, for the sake of consistency, they also state that "Respironics Autos won't respond to an apnea at any pressure unless it is preceded by an apnea," if that is the case?

Or do I misunderstand what I read in the other thread, linked in my previous post in this thread?

You may misunderstand the implications:
A person with "stand alone apneas" above 10 cms will be stuck at the minimum pressure on the auto, regardless of how many apneas they have and regardless of how frequently they occur. This it not the case with a Respironics.

As for the statement, "How many apneas are actually preceded by snores and flow limitations as compared to frank apneas would be the determination as to whether the ResMed Auto would work for them," couldn't the statement could also be made, "How many apneas are actually preceded by other apneas would be the determination as to whether the Respironics Auto would work from them"?

Or do I misunderstand?

Yes you misunderstand. The Respironics alrgorithm behaves differently depending on what state it is in. It constantly searches for the best pressure, by going up or down from a "therapy" pressure. It stays at "therapy" pressure for 5 minutes, then goes down, in search for lower pressure, or up, in a search for improvement. While in therapy pressure, or searching for improvement, it will raise the pressure 1 cm. if 2 apneas are detected within 3 minutes. However, if all is fine, and it drops pressure in a search for more comfort, and then runs into an apnea, it will raise the pressure immediately in response to this single apnea. Regardless of present pressure So basically, if you're not at pressure high enough to handle your apneas, the Respironics will raise you pressure till you settle down.
The Respironics up and down cycly means that if pressure is suboptimal, it will respond immediately and unconditionally to a single apnea.

I "get" that snore and flow limitations don't necessarily mean that an apnea is going to take place. And I "get" that an apnea can take place without being preceded by FLs and snores. But wouldn't it also be true that an apnea doesn't necessarily mean that another apnea is going to take place, and that an apnea can take place without being preceded by another apnea?

Actually that is exactly the point. When at therapeutic pressure, or searching for improvement, a single random apnea is not considered cause enough to raise the "therapeutic" pressure definition. (One swallow does not...). 2 within 3 minutes mean a change is called for. And, since part of the algorithm is a challenge (down) and a search for improvement (up) every 5 minutes, you are not doomed to having constant suboptimal pressure just because your apneas happen to occur every 4 minutes.

Or do I misunderstand?

Yes, you misunderstand.
All other conditions being equal (no flow limitation, no snores) A cluster of apnea's will indicate to the Respironic's that it has to raise the pressure since the present pressure is no longer therapeutic. It will not do so for a Resmed above 10. Ever.

And that is the important point.

Try to get you hands of the full text of the following article:

Respiration 2008;75:48–54
Titration Efficacy of Two Auto-Adjustable Continuous Positive Airway Pressure Devices Using Different Flow Limitation-Based Algorithms
Katrien B. Hertegonne et al.
O.

[jnk]

Thanks, ozij. I'll try to get my hands on that article. I have a LOT to learn, and your time and patience are VERY much appreciated.

I am still not getting the larger point on most of this stuff, I guess.

But much of my "argument" above is that I can as easily take a portion of the Respironics algorithm out of context and word it in a way that would make Respironics look bad, just as others, in my opinion, often take a portion of the ResMed algorithm out of context in what seems to be an attempt to imply that one brand's autos are significantly inferior to the other because of a choice in approach. For example, I could say of Respironics that because it periodically drops the pressure as a search in the name of comfort, that it actually causes the solitary apnea that the machine then responds to. Would that be an oversimplification? Sure it would. But would it be a more egregious oversimplification than the way that the 10-cm-ResMed-cutoff-line is often presented on this board by some? I don't think so. Then again, I am too new to be emphatic even about that opinion, since my opionions are very subject to change.

Thanks for trying to help me understand. But it may take me a while. Please continue to be patient with me!

jeff

[ozij]

The fact that anyone can take anything out of context and use that for rhetorical puposes does not indicate when something is taken out of context.

As a matter of fact, my link to the full chat it talkaboutsleep was an atttempt to give you - and others the context. I guess you didn't click on it. It's an old chat but the information is just as relevant today.

So here is a reply to just one question on that chat:
http://www.talkaboutsleep.com/sleep-dis ... chat.htm#6

Moderated Chat Transcript: The ResMed AutoSet Spirit™ and S7 Elite™ CPAP
With ResMed's Simon J.P. Johnson

Simon J.P. Johnson, ResMed Sr. Product Manager. He came to ResMed in 2001 with eight plus years of international sales and marketing experience in medical devices. Mr. Johnson Holds a BA in Public and Business Administration from San Diego State University

6. Why does AutoSet Spirit (and AutoSet T™) have the A10 algorithm?

ResMedSimon answers: The A10 algorithm increases pressure in response to Flow Limitation, Snore, and Apnea up to 10cm H2O. Above 10cm H2O, pressure response to Flow Limitation and Snore continues, but there is no response to Apnea. AutoSet Spirit and AutoSet T do not differentiate between obstructive and central apneas. Increasing pressures above 10cm H2O in response to apnea can lead to "runaway" central apneas

O.