CPAP vs Auto Setting

[Midnight Son]

My machine has been set in CPAP mode, at 9 cm since I began using it. I fell off treatment for an lengthy period, but a number of health issues reinforced the important of re-establishing the discipline. For the past five weeks I have been 100% compliant, averaging @ 9hrs use per night.

My last sleep study was in 2011, at which the 9cm CPAP was established. As I have a Respironics Remstar Auto C-Flex CPAP I decided to try the auto setting to see if my patterns had changed such that it would auto titrate to a higher setting. I set the minimum at 8cm as I was fairly sure the pressure might be higher vs. lower.

So, How can I tell what the machine reached in Auto mode? I found helpful posts and videos for adjusting settings, but nothing about how to determine the results of the Auto setting. Is my machine capable of telling me?

Many thanks!

[Wulfman...]

My machine has been set in CPAP mode, at 9 cm since I began using it. I fell off treatment for an lengthy period, but a number of health issues reinforced the important of re-establishing the discipline. For the past five weeks I have been 100% compliant, averaging @ 9hrs use per night.

My last sleep study was in 2011, at which the 9cm CPAP was established. As I have a Respironics Remstar Auto C-Flex CPAP I decided to try the auto setting to see if my patterns had changed such that it would auto titrate to a higher setting. I set the minimum at 8cm as I was fairly sure the pressure might be higher vs. lower.

So, How can I tell what the machine reached in Auto mode? I found helpful posts and videos for adjusting settings, but nothing about how to determine the results of the Auto setting. Is my machine capable of telling me?

Many thanks!

Huh?
So, you were going to try an experiment without being able to determine the outcome?

OK.
You need to use the same stuff I use........as I have similar generation equipment (listed in my profile).
You need to have the Encore Pro or Encore Viewer software.
You need to have an Infineer/Mako DT-3500 card reader to read the smart card that SHOULD be in your machine. If there isn't one, you need to get one.
You would need a computer with a Windows based operating system. If you're still using XP, that would be even better.


Den

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[Pugsy]

Encore Basic would also work and isn't as big of a PITA as these newer versions of Pro. I can help out with Basic (it is also strictly Windows software). Can't use SleepyHead with your machine so you are stuck with some version of Encore.
I think I may know of someone who wants to get rid of an Infineer DT3500 card reader.

[Midnight Son]

Wulfman, As I understand the Auto setting/capability vs. straight CPAP at 9cm, the auto setting will optimize the treatment level. Setting the auto minimum near to the 9cm CPAP will avoid the machine regularly starting at a needlessly low setting (i.e. 4cm with daily recurring periods of ineffective pressure). I intend to leave the machine on the Auto setting, as it should optimize to my real need vs. the sleep study snapshot which was done 45 months ago.

I was primarily curious if the machine would indicate what the auto setting determined . It wasn't an experiment per se.

I don't have a windows computer (all iMac/iPad). It probably makes more sense to invest in a current CPAP auto model (which I assume would provide the data) than invest in extra stuff for my outdated machine, particularly since I would also have to get a windows computer which holds little interest. I was hoping I could just look at the current machine for the info.

I welcome additional comments, particularly if the change to the auto setting is ill advised.

Thanks for your suggestions.

[Julie]

If you have a machine that gives data - more than just hrs of use for compliance - then you can use the SleepyHead program (works with Macs) free to download from diff places on the forum, but of course you also need a card reader (either already in your Mac depending on the model), and/or a usb cable connection. The card itself would be in your machine and removed daily (or weekly) to see your stats.

[Wulfman...]

Wulfman, As I understand the Auto setting/capability vs. straight CPAP at 9cm, the auto setting will optimize the treatment level. Setting the auto minimum near to the 9cm CPAP will avoid the machine regularly starting at a needlessly low setting (i.e. 4cm with daily recurring periods of ineffective pressure). I intend to leave the machine on the Auto setting, as it should optimize to my real need vs. the sleep study snapshot which was done 45 months ago.

I was primarily curious if the machine would indicate what the auto setting determined . It wasn't an experiment per se.

I don't have a windows computer (all iMac/iPad). It probably makes more sense to invest in a current CPAP auto model (which I assume would provide the data) than invest in extra stuff for my outdated machine, particularly since I would also have to get a windows computer which holds little interest. I was hoping I could just look at the current machine for the info.

I welcome additional comments, particularly if the change to the auto setting is ill advised.

Thanks for your suggestions.

That's a misconception or misunderstanding of how APAPs work. Auto machines (set in a range of pressures) only respond to POTENTIAL precursor events......Snores and Flow Limitations. Not all people have either or both of those. If they are prone to having "frank" (without preceding events, out of nowhere) apneas, the machine will NOT respond to try to prevent them. APAP machines will also not respond to apneas in process. It takes at least 10 seconds of no breathing to define an apnea. They will wait till they're over or avoid pressure increases because they may be Centrals and they try to avoid triggering Central Apneas.

Pressure changes won't "optimize" therapy if they encounter precursor events that occur in deeper or REM sleep stages......they can bump the user out of the needed sleep stage and leave them feeling unrested.


Den

.

[Wulfman...]

If you have a machine that gives data - more than just hrs of use for compliance - then you can use the SleepyHead program (works with Macs) free to download from diff places on the forum, but of course you also need a card reader (either already in your Mac depending on the model), and/or a usb cable connection. The card itself would be in your machine and removed daily (or weekly) to see your stats.

Julie,

He has an old Legacy Auto like the ones I've got listed in my profile. They use the old "smart cards".
Sleepyhead won't work with those machines.


Den

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[palerider]

That's a misconception or misunderstanding of how APAPs work. Auto machines (set in a range of pressures) only respond to POTENTIAL precursor events......Snores and Flow Limitations. .

again, I feel that the way you lay this out is misleading. apaps DO respond to what they determine is obstructive apneas, and hypopneas. of course the response isn't before the a/h happens, it's afterwards, but they *do* respond.

[Wulfman...]

OK. I went into the "program" .xml file for the Auto algorithm demonstration program for the Legacy model of the REMStar Auto and copied what I felt were the pertinent sections for this discussion. I also included some info regarding how they respond to leaks.
I guess the words "response" (or "respond") and the "attempt to treat or not" conditions can be debated ad-nauseum.

.

Apneas and Hypopneas are determined by establishing a reference that is based on a moving flow signal window that is a few minutes in duration.

Apneas and Hypopneas are detected as a reduction in flow lasting for at least 10 seconds.
Apnea - 80% reduction in flow
Hypopnea - 40% reduction in flow

Response to Apneas and Hypopneas: Ptherapy
While in Ptherapy mode, if 2 apneas/hypopneas are detected within 3 minutes, the algorithm increases pressure by 1 cmH2O.
Re-initiate Ptherapy for 5 minutes.

Response to Apneas and Hypopneas: Poptimum
In Popt search mode, if 2 apneas/hypopneas are detected within 3 minutes, the algorithm increases pressure by 1 cmH2O.
Re-initiate Ptherapy for 5 minutes.

Detection of Non-Responsive Apneas and Hypopneas
Above 8 cmH2O pressure, the pressure increase for sustained apneas/hypopneas is limited to 3 cmH2O above the pressure setting at the onset of the apnea/hypopnea sequence.
The pressure setting at the onset of the sequence is called the "Onset Pressure."
The pressure 3 cmH2O above the "Onset Pressure" is called the "NRAH Threshold."
"NRAH" is an acronym for "Non-Responsive Apnea/Hypopnea."

Detection of Non-Responsive Apneas and Hypopneas
An apnea/hypopnea x2 event detected after reaching the NRAH Threshold is considered to be non-responsive.

Detection of Non-Responsive Apneas and Hypopneas
A special case of Non-Responsive A/H is when the events are hypopneas only, with no apneas.

Detection of Non-Responsive Apneas and Hypopneas
After seeing two Hypopneas, the algorithm increases the pressure by 1 cmH2O, and the Onset Pressure resets to this new pressure level.

Detection of Non-Responsive Apneas and Hypopneas
However, the Onset Pressure can not be raised above 12 cmH2O by a sustained string of Hypopnea-only events.
This does not imply that the Onset Pressure value can not be set above 12 cmH2O. It only states that the Onset Pressure can not be RESET above 12 cmH2O due to a string of Hypopnea-only events.
The maximum NRAH Threshold due to a sustained string of Hypopnea-only events will be 3 cmH2O above 12 cmH2O.

Response to Non-Responsive Apneas and Hypopneas
When the device encounters a non-responsive apnea or hypopnea, it will decrease pressure by 2 cmH2O and hold the pressure for 15 minutes.
During this 15-minute "NRAH-hold" period, the pressure will be changed only in response to detection of a sequence of vibratory snore events.
The reason for this increase in pressure followed by a decrease in pressure when an apnea/hypopnea is not responsive is to allow the device to respond appropriately to an event that is not treatable by increases in pressure, such as a central apnea.

Elevated Leak Levels represent an exception condition
The persistence of large leaks, particularly when the patient's breaths have small tidal volumes, could potentially induce false apnea and hypopnea detection. Therefore, the REMstar Auto monitors the patient's flow over several minutes.
The patient's flow is compared to "expected leak." "Expected leak" is a value that has been determined through testing of various mask and tubing combinations.

Elevated Leak Levels
As the pressure is increased, the "expected leak" also increases.
The algorithm operates normally while the patient's flow is less than two times the "expected leak."

Elevated Leak Levels
This increased flow is considered to be in "large leak" if the threshold is exceeded for more than 1.5 minutes.

Elevated Leak Levels
The REMstar Auto system responds to the "large leak" by dropping the pressure 1 cmH20 every two minutes until the "large leak" condition is cleared.
As the pressure is dropped, the "expected leak" also drops.

Elevated Leak Levels
The "large leak" is cleared when the patient's flow falls below the threshold for more than 1.5 minutes.


Den

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[Midnight Son]

Thanks all for your replies, especially Den .

I'm not trying to be misleading, it is more related to my lack of understanding (due to my absence from treatment and this site). I do appreciate the guidance. Absent a current capability to collect and interpret data I am wondering if I should reset the machine to fixed CPAP pressure at 9cm or leave it on Auto?

I will investigate the cost of additional data analysis HW/SW Den recommended, but don't want to get a Windows computer solely for this purpose. I should also compare upgrading my CPAP equipment to something that has integrated data analytics and is compatible with an iMac. I am sure there are threads I can read on equipment recommendations, so no need to repeat detailed advice here.

[Pugsy]

Here's an idea I will throw out there for you.
I can check to see if the person who had the DT3500 still has it...maybe she will loan it to us..she upgraded to newer machine and no longer needs the DT3500.
She can send it to me... you snail mail me your smart card...and I will get some reports for you with my Encore software
Then I email the reports to you and snail mail your smart card back to you.

You only get 7 days of detailed daily reports but the summary data is long term.
Would give you and idea what is going on anyway without much cost...cost of the postage for the smart card to me...which isn't much and will work out something with her on the DT3500 postage.
This way you wouldn't have to worry about a new computer and all that now...you would just have to worry about me knowing your snail mail address...but we would be equal because you would have mine. All done via private messages though.

It's an idea...answer some of your questions for the moment anyway. I would be happy to do it.
My first machine 5 years ago used the smart card thing but I long ago sold my DT3500.

I know of a source for brand new DT3500 reader for $40 plus 6.50 shipping...if you wanted to go that way.

[Wulfman...]

Thanks all for your replies, especially Den .

I'm not trying to be misleading, it is more related to my lack of understanding (due to my absence from treatment and this site). I do appreciate the guidance. Absent a current capability to collect and interpret data I am wondering if I should reset the machine to fixed CPAP pressure at 9cm or leave it on Auto?

I will investigate the cost of additional data analysis HW/SW Den recommended, but don't want to get a Windows computer solely for this purpose. I should also compare upgrading my CPAP equipment to something that has integrated data analytics and is compatible with an iMac. I am sure there are threads I can read on equipment recommendations, so no need to repeat detailed advice here.

There are some options to be able to run Windows environments on Mac computers. I've never used an Apple computer so I'm not familiar with those option......but I've seen them discussed on the forum. So, that's one option.
Another option would be to find an el-cheap-o used Windows computer to load the stuff on.

I've always been an advocate of using software ESPECIALLY when using a range of pressures. In the absence of that (for the time being), I would "recommend" using a straight pressure......maybe 9 or 10......and see how that goes till you figure out what your options are with the software.

On the "plus" side, these old Legacy machines (we have) were and still are fully-data-capable machines and provide great therapy.
On the "minus" side, they don't display any therapy data (summaries) in the LCD screens like the newer machines do.

But, to REALLY "see" what's going on, you need to download the data from the cards and run it through the software.
The summary data in the LCD screens is not very informative in that regard.


Den

.

[fdw]

I'm sorta I the same boat as you.....only a month or so ahead of you. I've been on CPAP since March 1995 and yet I've only been a member here for a month.....who would have thunk it.
I ended up buying the ResMed S9 AutoSet, and downloading SleepyHead to use with my MacBook Pro 10.9.5......works great.
My last machine purchase and titration study was 2007 (13.0 CPAP)...so I replaced a 7 year old machine...I also went to a full face mask and loving it.
Currently I'm in APAP mode 12.0 minimum and 16.0 maximum EPR 1.0. Still tinkering mainly with EPR settings. My AHI has been anywhere from 3.50 maximum (once, started using FFM) to 0.00 minimum (once) with an average of 1.2
I'd suggest to consider upgrading your equipment.....if it's not working for you. Don't mess with settings until you can see what's happening (results).

[Wulfman...]

Here's one component, if it's still for sale.

viewtopic.php?f=1&t=100855&p=940844&hil ... er#p940844


Den

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[palerider]

Response to Apneas and Hypopneas: Ptherapy
While in Ptherapy mode, if 2 apneas/hypopneas are detected within 3 minutes, the algorithm increases pressure by 1 cmH2O.
Re-initiate Ptherapy for 5 minutes.

Response to Apneas and Hypopneas: Poptimum
In Popt search mode, if 2 apneas/hypopneas are detected within 3 minutes, the algorithm increases pressure by 1 cmH2O.
Re-initiate Ptherapy for 5 minutes.

good to see even the older machines respond to (after the fact) apneas and hypops.

Elevated Leak Levels
The REMstar Auto system responds to the "large leak" by dropping the pressure 1 cmH20 every two minutes until the "large leak" condition is cleared.
As the pressure is dropped, the "expected leak" also drops.

I'd seen robysue posting that machines lowered pressure in response to excess leaks (the opposite of so many people's "the pressure ran away because I was having leaks!" claims) but I hadn't seen it documented as such, even in the last generation too

thanks!