Respironics Bipap Auto First Night Impression

Guest · Post by **Guest** » Tue Nov 01, 2005 8:02 pm

My second guess is that a setting of EPAPmin=6, IPAPmax=14, and MAXps=4 may behave as follows:

Your autoBiPAP would self-adjust, delivering between a max of 14/10 and a min of 6/6. As long as you did not experience heavy airway closures during the middle or end of expiration that 4 cm EPAP/IPAP pressure split would be maintained for the sake of comfort---but added comfort just might be achieved near the bottom of that range as the IPAP approaches EPAP-min (via a sliding "MAXps"). Again, heavy or atypical airway closures during expiration would cause the self-adjusting BiPAP to automatically move EPAP closer to IPAP, even as IPAP delivers near the middle or top of it's allowable range.

There are two parameters that may adjust: 1) how high or low the IPAP/EPAP delivery travel as a pressure-ascending or descending pair, and 2) how close or far IPAP/EPAP stay relative to each other. That first one will be limited by IPAPmax and IPAPmin, while that second one will be limited by MAXps. this is complex stuff for sure.

sthnreb · Post by **sthnreb** » Tue Nov 01, 2005 8:37 pm

There is also a split night time setting too. It allows you to modify the setting for split night time, which indicates the amount of time spent in bi-level or bi-level with bi-flex mode before transitioning to auto bi-level or auto bi-level with bi-flex mode. It can be set to 0 (off) and from 2-4 hours in 1 hour increments when the heat or ramp button is pressed. So I assume you can go half and half in a night. What you are saying then guest is it doesn't maintain a 4 cm difference, the epap goes up. I thought Ted said it would maintain the 4 cm difference at any setting? I guess I am trying to understand how to set it up. I have it set now for straight bipap with biflex, same as my old one, 12/8. Guess I will run this until I figure the settings and what is best for me. Waiting for the Encore Pro update too.

Guest · Post by **Guest** » Tue Nov 01, 2005 9:25 pm

What you are saying then guest is it doesn't maintain a 4 cm difference, the epap goes up.

I'm only speculating based on the name of that parameter: "MAX ps". Max pressure split? Max pressure spread? Max pressure support? "Max" sounds like an "upper cap" or "upper limit". "Max ps" to me does not sound like a fixed delta. Rather, it sounds as if the autotitrating algorithm nay close the EPAP/IPAP split on an as-needed basis.

I sure could be wrong---very wrong! Just don't know why a fixed delta would be ever be called "MAX ps". It will be very nice hearing more and more details about this machine! Hope you, Ted, and others share your discoveries with us!

Guest · Post by **Guest** » Tue Nov 01, 2005 9:42 pm

Where can I post it or send...I have the setup as a pdf.

Guest · Post by **Guest** » Tue Nov 01, 2005 10:15 pm

Where can I post it or send...I have the setup as a pdf.

Anybody have a solution?

There is also a split night time setting too.

Traditionally Respironics has made "split night" mode available to perform a sleep study. The first part of that split night study was used to log untreated (or minimally treated) sleep events, while the second part of that same night was run in autotitration mode.

Very few patients have reported finding this feature useful.

sthnreb · Post by **sthnreb** » Wed Nov 02, 2005 6:29 am

If anyone wants to download the setup options for the auto:

http://s8.yousendit.com/d.aspx?id=2T5Q9 ... U5AYB32FV2

sthnreb · Post by **sthnreb** » Wed Nov 02, 2005 8:09 am

The settings for Min EPAP, Max IPAP, and Max PS are highly interdependent. Consider the range of allowable pressures as bounded at the top by the Max IPAP setting and at the bottom by the Min EPAP settings. While setting up one parameter, another may change accordign to the following set of rules.

* The device will not allow a Max PS setting outside the range of 3.0 to 8.0 cm H2O, and the device will prohibit other settings to ensure that this rule is not violated.
* Within the range of 3.0 to 8.0 cm H2O, any setting can be chosen for Max PS, but it is further subject to the following rule: The Max PS setting cannot exceed Max IPAP setting minus Min EPAP setting.
* If the Min EPAP setting is incremented greater than Max IPAP setting minus Max PS setting, it will force the Max PS to decrease. The Max PS setting will only decrease down to the minimum setting of 3.0 cm H2O, so Min EPAP setting cannot be incremented greater than Max IPAP setting minus 3.0.
* If the Max IPAP setting is decremented less than Min EPAP setting plus Max PS setting, it will force the Max PS to decrease down to the minimum setting of 3.0 cm H20, so Max IPAP setting cannot be decremented less than Min EPAP setting plus 3.0.

jondough · Post by **jondough** » Wed Nov 02, 2005 12:12 pm

In reading the provided Setup Settings information and "Rules", I do not see that there is anything in there that says that the minimum PS cannot be lower than 3cm. It constantly refers to the fact that the minimum PSMax can be is 3cm.

The phrasing for the setting of IPAP and EPAP is exactly as in my BiPro2 manual, which I can set below three which I have tried to see if I could stand an AutoPAP, which I probably can't.

Unless that is specified somewhere else. One man's reading.

wading thru the muck! · Post by **wading thru the muck!** » Wed Nov 02, 2005 12:45 pm

jondough wrote:In reading the provided Setup Settings information and "Rules", I do not see that there is anything in there that says that the minimum PS cannot be lower than 3cm. It constantly refers to the fact that the minimum PSMax can be is 3cm.

The phrasing for the setting of IPAP and EPAP is exactly as in my BiPro2 manual, which I can set below three which I have tried to see if I could stand an AutoPAP, which I probably can't.

Unless that is specified somewhere else. One man's reading.

There is no PSMin setting available. It appears that the only setting that controls the IPAP/EPAP delta is referred to as the PSMax setting and it has a range of 3cm to 8cm. It may be inaccurate to name it PSMax, but as far as I can see, there is no separate Min setting to go along with the PSMax.

sthnreb · Post by **sthnreb** » Wed Nov 02, 2005 12:55 pm

[quote="Titrator"]Hi Folks,

I have my unit set to Auto Biflex. There is an IPAP Max control that can be set up to 25cm and it has an IPAP Min, which can be set as low as 4cm. I have IPAP Max set to 20cm and the EPAP min set to 10cm. My normal bipap pressure is set to 19.5 IPAP and 14.5 EPAP. There is a Max PS control that allows you to set the Delta range between 3 cm and 8cm. This is to always keep your IPAP and EPAP split a certain amount of cm no less than 3cm, and no more than 8cm. I have this setting set to 6cm.
https://www.cpap.com/productpage/bipap- ... ifier.html

Guest · Post by **Guest** » Wed Nov 02, 2005 1:42 pm

"PS Max" is not a misnomer. This is an auto-titrating BiPAP, guys! The BiPAP's algorithm will automatically reduce the difference between EPAP and IPAP if and only if there is just cause based on sensed sleep events. "PS Max" is exactly as it sounds: it is an upper limit and not a fixed delta.

Set PS Max to 3 cm and it will keep the pressure spread between IPAP and EPAP at 3 cm most or all the time. However, hook a patient up to that machine with heavy or atypical airway closures during expiration and watch the autotitrating algorithm automatically move EPAP up toward IPAP's value to clear the airway during expiration.

You guys really have to get beyond thinking of PS Max as if it were a fixed delta and start thinking of it as operating exactly the way Respironics labelled it.

Guest · Post by **Guest** » Wed Nov 02, 2005 2:03 pm

Almost all sleep labs in the land set EPAP at exactly 3, 4, or 5 cm under IPAP. When you guys experimentally set your PS Max at a whopping 8 cm, you defy current best practices. Go to Binarysleep.com and you will see sleep techs discussing at length why they normally do not want a patients EPAP/IPAP spread too high.

Unless you know the exact ramifications of running (even in autotitration mode) with such a wide EPAP/IPAP spread, I'd suggest setting PS Max to no more than the same IPAP/EPAP difference your sleep lab or doctor set you up with.

The larger the EPAP/IPAP split, the closer you get to actually supporting the respiratory drive versus simply providing expiratory comfort while clearing your obstructions.

PS Max = 8! Wow!! Can you say "ventilatory support"?

sthnreb · Post by **sthnreb** » Wed Nov 02, 2005 2:05 pm

Yeah, guess you are right Guest. I reset mine to IPAP 20, EPAP 4 and Max PS to 4. When I turned it on, the EPAP was 4 and the IPAP was 6. So, I laid down to see what would happen. After about 20 minutes I was thinking hey this is not to low and is is feeling pretty good now. So, I looked at the machine and it was then at 8 EPAP and 11 IPAP. My normal bipap settings are 12/8. So, I guess the 12/8 bipap setting was close. Plus, with this auto, it will adjust to whatever is needed. Kewl.

jondough · Post by **jondough** » Wed Nov 02, 2005 2:13 pm

I think that sthnreb's two last posts show that the unit does not have a PSmin of 3 as he reports two occasions of 2. Part of the discussion on P2 of this thread was could it go lower than 3, really to .5 or 0 to use the unit efffectively as a autoCPAP, though why you would want to dumb down such a great improved machine escapes me.

Guest · Post by **Guest** » Wed Nov 02, 2005 2:32 pm

Doesn't dumb down the machine if EPAP and IPAP converge for good reason, Johndough. I can think of at least two good reasons for this algorithm to want to allow EPAP and IPAP to converge:

1) providing a higher expiratory pressure on-demand to keep the airway open (on an as-needed basis), and

2) Quite possibly comfort in the low range. As an example: with an IPAP max of 14 cm, and EPAP min of 9cm, and a Max PS of 4 cm.... 9/9 might be more comfortable than 13/9! If there are no obstructions to clear at 9/9, then why
wouldn't an autotitrating algorithm bring IPAP down for the sake of comfort?

That wouldn't be dumbing it down... rather that would be increasing the on-board smarts.

Respironics Bipap Auto First Night Impression

Re: Respironics Bipap Auto First Night Impression

PS Max

Less than 3 PS seems possible.

Machine

Additional Comments: Resmed AirCurve 10 VAuto BiLevel with HumidAir