Quantcast

Bookmark and Share
General Discussion on any topic relating to CPAP and/or Sleep Apnea.
williamco
 
Posts: 238
Joined: Wed Aug 12, 2009 5:32 pm
Gender: Male

what is the optimal difference between IPAP & EPAP?

Postby williamco on Tue Oct 06, 2009 11:48 am

On a BiPAP machine, is there an optimal difference between inahle and exhale pressure? like 3-4-5 cm..etc?
thanks

_________________
Mask: Mirage Activa™ LT Nasal CPAP Mask with Headgear
Humidifier: M Series Heated Humidifier
Additional Comments: Pressure at 12 cmh2o

User avatar
Slinky
 
Posts: 11414
Joined: Wed Nov 01, 2006 3:43 pm
Location: Mid-Michigan
Gender: Female

Re: what is the optimal difference between IPAP & EPAP?

Postby Slinky on Tue Oct 06, 2009 12:08 pm

I don't think there is any real consistency of opinion on this amongst the sleep profession.

I was first titrated at IPAP 13, EPAP 8 and the script didn't include a number for Pressure Support but my VPAP Auto (bi-level) arrived set at a Pressure Support of 4.

My second bi-level titration ended up w/IPAP at 10, EPAP at 5 and the script included a Pressure Support of 5.

A very good PSGT friend has said that a Pressure Support of 6 has been successful for him and at his sleep lab.

The experienced PAPpers in this forum when offering advice on APAP pressure settings usually recommend 1-2 cms BELOW the titrated pressure and 2-4 cms ABOVE the titrated pressure which would give a pressure range of 4-6.

jnk gave us an EXCELLENT description of how the Pressure Support differs between the Resmed and the Respironics bi-levels and how the settings for the one brand should differ from the settings of the other brand. And dsm added a further way of clarifying the differences.
--------------------------------------------------------------------------------------------
(Note, however, just for the record for those doing the math at home, IF it is a ResMed autobilevel set with a minimum EPAP of 6, a maximum IPAP of 19 and a pressure support of 3, the machine would, with those settings, have a full 10 cm of distance to range in--from a low of 6/9 to a high of 16/19.)

http://www.sleepguide.com/forum/topics/bipap-results-for-response?id=2549090%3ATopic%3A18576&page=2#comments

I think you may misunderstand the differences between the two machines and how each machine must be set. They are both good autobilevels, but you can't set either of them up correctly by attempting to use the numbers that were used on the other brand of machine. You have to think about the numbers and translate them for how you want the other brand of machine to run.

As an illustration, think of inhale and exhale as being two dancers. On the Respironics dance floor in the Respironics world, the two dancers dance two different dances without caring what the other dancer is doing. You simply set the size of the dance floor and you tell the dancers the maximum distance they are allowed to get from each other during their separate dances (there is an automatic minimum to keep them from bumping into each other), and they each do their own thing. Sometimes they dance close to each other, and sometimes they dance far apart. That distance varies. On the other hand, on a ResMed dance floor in the ResMed world, the two dancers do the same dance and are always the exact same distance from each other, but they can still roam the full dance floor, as long as they do it together. So if you mistakenly set the fixed distance of the dancers to be the same size as the dance floor, you keep the dancers from moving at all.

In other words, for the Respironics machine, you set the maximum IPAP and minimum EPAP (the size of the dance floor), then you set the MAXIMUM pressure support, or maximum distance allowed between the two separate pressures (dancers). For the ResMed, you similarly set a maximum and minimum (the dance floor), but then you set the ACTUAL pressure support, the fixed distance (or, difference) between inhale pressure and exhale pressure for the night. On that machine, those two pressures increase and decrease TOGETHER, NOT SEPARATELY, moment to moment, during the night (since the two do the same dance together).

It seems that the person who set up your machine didn't understand that difference between the two machines and set up the ResMed as if it were a Respironics. That is incorrect. If you want the ResMed to run as an auto, make sure the pressure support number is a number LESS THAN the distance between Max IPAP and Min EPAP so the dancers have some room to move. If the machine isn't set up correctly, it is the person who set it up who has kept the machine from running as an auto. That is not a limitation of the machine; it is a limitation of the person who set it up. That person was confused. So don't blame ResMed.

As for which approach to autobilevel dancing is best, I don't know. I just know the two approaches are different and that before you set up one brand after using another brand, you had better learn something about dance floors and choreography in the other world and translate from one to the other, if you want to see a dance.
--------------------------------------------------------
there is nothing wrong with keeping the dancers pinned, if that's what a person wants to do. Some like the feel of a ResMed autobilevel in auto mode (because of how Easy-Breathe feels) but don't want the pressures to move around at night. So to get straight bilevel while the machine is in VAuto mode, they purposely make the pressures stay the same by setting pressure support the exact distance between Min EPAP and Max IPAP. But if a person wants to use a ResMed autobilevel as an autobilevel, the stick has to be shorter than the walls or the pressures won't vary.
--------------------------------------------------------
from dsm

Here are a few words that I hope might (for some) clarify this difference. I am going to add dancing up the floor (higher pressures) & dancing down the floor (lower pressures) ...

The Bipap Auto starts off (no user input can set this ) with a minimum gap of 2 CMs between epap & ipap (lets call this 2 feet between the dancers named ipap & epap ) - as the night progresses, the epap dancer may try to move up the floor because epap feels uncomfortable down the floor thus pushing the partner (called ipap) at least 2 feet ahead any time epap dances up the floor. But ipap may dance up the floor & leave epap behind so the gap may widen beyond 2 feet (but there is that rope tying them together called Max PS (or max feet apart)) - If ipap dances so far from epap that the rope gets tight, ipap will drap epap along up the dance floor providing ipap doesn't hit the wall first in which case ipap can't go any higher up the floor.

Now with the Vpap dance again we have epap & ipap BUT, the rules of the dance are that these two will always stay a preset gap apart (this could be set to 3 CMs or 4 or whatever). There is also the max pressure (or distance up the floor ) that ipap can dance to (before hitting the limit set. Epap may dance up the hall but will always push ipap this preset gap ahead.

For Bipap machines the gap between epap & ipap varies as each pressure gets adjusted Independently (never less than 2 & never greater than PSMax (usually ).

For Vpap machines the gap between epap & ipap gets pre set & stays that way as long as epap can push or pull ipap within the boundaries of their dance area. They always stay the same distance apart vs Bipap where the gap varies depending on how epap & ipap each feel.

I just hope this addition doesn't mangle the whole dance routine
--------------------------------------------------------------------------------------------------
After all this is said and done - choose your own poison. Good luck!
Slinky

_________________
Mask: Quattro™ FX Full Face CPAP Mask with Headgear
Additional Comments: PR SystemOne BPAP Auto w/Bi-Flex & Humidifier - EncorePro 2.2 Software - Contec CMS-50D+ Oximeter - Respironics EverFlo Q Concentrator
Women are Angels. And when someone breaks our wings, we simply continue to fly.....on a broomstick. We are flexible like that.
My computer says I need to upgrade my brain to be compatible with its new software.

User avatar
rested gal
 
Posts: 12889
Joined: Thu Sep 09, 2004 10:14 pm
Location: Tennessee
Gender: Female

Re: what is the optimal difference between IPAP & EPAP?

Postby rested gal on Tue Oct 06, 2009 12:17 pm

I don't know that it's "optimal" -- but I think 4 cm H2O is often prescribed for the difference between IPAP/EPAP settings when using a plain bilevel machine or using a bilevel auto machine in plain bilevel mode. Like IPAP 16 - EPAP 12.

What's optimal for one person, however, might be very "off" for another person on bilevel therapy. Might depend on why they are prescribed bilevel in the first place. Might also depend on other settings (rise time, etc.) since a change in one setting might change the effect of a completely different setting on the person's therapy.

If a BiPAP Auto (or VPAP Auto) is being used in autotitrating bilevel mode, however, IPAP/EPAP settings become "IPAP max" and "EPAP min" settings, and the optimal setting for those two could be quite different from plain bilevel IPAP/EPAP.

If a person has a BiPAP Auto or VPAP Auto and will be using it in auto bilevel mode, the link Slinky provided to jnk's post is essential reading, imho. Thanks for including that link, Slinky! :)
S9 VPAP Auto - S9 Auto - BiPAP Auto - 420E auto - Everest 2. ResScan, EncPro & SL3.
Humidifier: F&P HC 150, Aussie heated hose.
Mask: Aeiomed Headrest/homemade straps.
ALL LINKS by rested gal:
http://www.cpaptalk.com/viewtopic.php?t=17435

williamco
 
Posts: 238
Joined: Wed Aug 12, 2009 5:32 pm
Gender: Male

Re: what is the optimal difference between IPAP & EPAP?

Postby williamco on Tue Oct 06, 2009 4:02 pm

slinky: thanks for the elaboration. can I summarized my understanding and correct me if I am wrong:

on Respironics:
BiLevel fixed: you set EPAP (lower) and IPAP (higher) . they stay fixed without any variation. no dance here

BiLevel Auto: you set EPAP minimum, and IPAP max, and pressure sup which should be equal or less than the difference between EPAP minimum and IPAP maximum. the dance choreography here is that IPAP and EPAP move independently between there max and min limits respectively with minimum difference between both of them of 2 cm and max difference is that of the max pressure support set

my question was at first case BiLevel fixed, what is the average difference between EPAP and IPAP ? I changed the word "optimal" to "average" to exclude the idea that every body has his own optimal, I am just asking about average.
also what is the maximum difference that can be taken

_________________
Mask: Mirage Activa™ LT Nasal CPAP Mask with Headgear
Humidifier: M Series Heated Humidifier
Additional Comments: Pressure at 12 cmh2o

User avatar
rested gal
 
Posts: 12889
Joined: Thu Sep 09, 2004 10:14 pm
Location: Tennessee
Gender: Female

Re: what is the optimal difference between IPAP & EPAP?

Postby rested gal on Tue Oct 06, 2009 11:42 pm

williamco wrote:on Respironics:
BiLevel fixed: you set EPAP (lower) and IPAP (higher) . they stay fixed without any variation. no dance here
Correct...when in just "fixed" bilevel mode. Machine is not in autotitrating bilevel mode.

williamco wrote:BiLevel Auto: you set EPAP minimum, and IPAP max, and pressure sup which should be equal or less than the difference between EPAP minimum and IPAP maximum. the dance choreography here is that IPAP and EPAP move independently between there max and min limits respectively with minimum difference between both of them of 2 cm and max difference is that of the max pressure support set
Correct again. One clarification...the most that the pressure support setting can be set for is 8 cm H20 (assuming that the min EPAP and max IPAP are set at least that far apart from each other in the first place.) Thus, when using the Respironics machine in Auto Bilevel mode the most difference you can set for min EPAP and max IPAP to "dance" apart from each other is 8 cm H20.

williamco wrote:my question was at first case BiLevel fixed, what is the average difference between EPAP and IPAP ? I changed the word "optimal" to "average" to exclude the idea that every body has his own optimal, I am just asking about average.
If by "average" you mean how far apart are those two settings usually prescribed, my guess is that 4 cm H2O apart is probably the way most "fixed" bilevels are usually prescribed to be set up unless an actual bilevel titration was performed and a different spread was found to be better for that person.

williamco wrote:also what is the maximum difference that can be taken
If you're still talking about fixed bilevel... with a single fixed IPAP and a single fixed EPAP, then the full range of the machine is the maximum difference that could be set for those two pressures. In a bilevel machine that had 25 as its top pressure, you could set it for fixed IPAP as high as 25 and fixed EPAP as low as 4... but I cannot imagine any doctor prescribing bilevel therapy like that!

3 or 4 or 5 or 6 cm H2O difference between fixed IPAP and fixed EPAP are the most common prescribed differences that I've seen mentioned on here by people using fixed bilevel machines.
S9 VPAP Auto - S9 Auto - BiPAP Auto - 420E auto - Everest 2. ResScan, EncPro & SL3.
Humidifier: F&P HC 150, Aussie heated hose.
Mask: Aeiomed Headrest/homemade straps.
ALL LINKS by rested gal:
http://www.cpaptalk.com/viewtopic.php?t=17435

User avatar
jnk
 
Posts: 5818
Joined: Mon Jun 30, 2008 3:03 pm
Location: Brooklyn Heights
Gender: Male

Re: what is the optimal difference between IPAP & EPAP?

Postby jnk on Wed Oct 07, 2009 6:09 am

rested gal wrote: I cannot imagine any doctor prescribing bilevel therapy like that!


I can only think of one doc who might. :D

As an only slightly related side point, I find it interesting that the clinical guide for my VPAP Auto says of its own capabilities/limitations in autobilevel mode:

" . . . In VAuto mode, if Pressure Support is above 6 cm H2O, treatment efficacy may
be reduced. . . . "


So I guess that if someone needed more than 6 cm PS for some rare reason, he or she would do well to run that machine in bilevel, not autobilevel, mode.

jeff
"All quotes are actually misquotes."-- Never directly attributed to Bartlett.

User avatar
rested gal
 
Posts: 12889
Joined: Thu Sep 09, 2004 10:14 pm
Location: Tennessee
Gender: Female

Re: what is the optimal difference between IPAP & EPAP?

Postby rested gal on Wed Oct 07, 2009 9:54 am

jnk wrote:
rested gal wrote: I cannot imagine any doctor prescribing bilevel therapy like that!


I can only think of one doc who might. :D
Right! I'd forgotten about him. :lol: :lol:
S9 VPAP Auto - S9 Auto - BiPAP Auto - 420E auto - Everest 2. ResScan, EncPro & SL3.
Humidifier: F&P HC 150, Aussie heated hose.
Mask: Aeiomed Headrest/homemade straps.
ALL LINKS by rested gal:
http://www.cpaptalk.com/viewtopic.php?t=17435

User avatar
ozij
 
Posts: 8721
Joined: Fri Mar 18, 2005 11:52 pm
Gender: Female

Re: what is the optimal difference between IPAP & EPAP?

Postby ozij on Wed Oct 07, 2009 10:16 am

rested gal wrote:
jnk wrote:
rested gal wrote: I cannot imagine any doctor prescribing bilevel therapy like that!


I can only think of one doc who might. :D
Right! I'd forgotten about him. :lol: :lol:


Hmmm, he must have come by when I was gone. Anybody care to share the joke?

O.

_________________
Machine: S9 AutoSet™ CPAP Machine
Mask: Hybrid Full Face CPAP Mask with Nasal Pillows and Headgear
Humidifier: S9™ Series H5i™ Heated Humidifier with Climate Control
Additional Comments: Software: Updated version of ResScan. First machine (5 years) was PB420E. Tried others including Autoset S8 II
And now here is my secret, a very simple secret; it is only with the heart that one can see rightly, what is essential is invisible to the eye.

Antoine de Saint-Exupery

-SWS
 
Posts: 5365
Joined: Tue Jan 11, 2005 7:06 pm
Gender: None specified

Re: what is the optimal difference between IPAP & EPAP?

Postby -SWS on Wed Oct 07, 2009 10:40 am

IPAP and EPAP dance? And a particularly wide IPAP/EPAP gap/band?

What a coincidence... I just got done posting about a wider-than-usual IPAP/EPAP gap/band a couple weeks back.

PS Hope I got that last link right... :wink:

(BiLevel Gap Dance credits:
IPAP- Laurel
EPAP- Hardy)

dlp1195
 
Posts: 42
Joined: Fri Aug 28, 2009 9:50 am
Location: Oklahoma
Gender: Male

Re: what is the optimal difference between IPAP & EPAP?

Postby dlp1195 on Wed Oct 07, 2009 11:15 am

I was sent home with a ResMed Vpap Auto 25 set at 4-25 with ps of 4 and did not work for me. I changed it to 10-25 and ps 4 and it has worked better but still do not have the numbers where I would like them to be. Just don't know which way to go. Am having a ResMed Advant SV titration on the 18th so just making do with what I have now. My average high pressure has been around 15 the past few weeks so I might change the high from 25 to say 16 and see if that helps. Any other suggestions? Did not intend to high jack this thread but wanted to add that there are DR.s or DME's that will send a machine out set like this.

User avatar
ozij
 
Posts: 8721
Joined: Fri Mar 18, 2005 11:52 pm
Gender: Female

Re: what is the optimal difference between IPAP & EPAP?

Postby ozij on Wed Oct 07, 2009 11:30 am

:D
Oh, that doctor. :lol: I was thinking of 25 / 4 so literally I didn't realize he's the one.

I never realized Laurel could move so lightly and flexibly!

O.

_________________
Machine: S9 AutoSet™ CPAP Machine
Mask: Hybrid Full Face CPAP Mask with Nasal Pillows and Headgear
Humidifier: S9™ Series H5i™ Heated Humidifier with Climate Control
Additional Comments: Software: Updated version of ResScan. First machine (5 years) was PB420E. Tried others including Autoset S8 II
And now here is my secret, a very simple secret; it is only with the heart that one can see rightly, what is essential is invisible to the eye.

Antoine de Saint-Exupery

User avatar
rested gal
 
Posts: 12889
Joined: Thu Sep 09, 2004 10:14 pm
Location: Tennessee
Gender: Female

Re: what is the optimal difference between IPAP & EPAP?

Postby rested gal on Wed Oct 07, 2009 4:11 pm

Yup. "That" one. :D
S9 VPAP Auto - S9 Auto - BiPAP Auto - 420E auto - Everest 2. ResScan, EncPro & SL3.
Humidifier: F&P HC 150, Aussie heated hose.
Mask: Aeiomed Headrest/homemade straps.
ALL LINKS by rested gal:
http://www.cpaptalk.com/viewtopic.php?t=17435


Return to CPAP and Sleep Apnea (CLICK HERE TO READ POSTS)

Who is online

Users browsing this forum: badgerwooz, englandsf, Grandma Judy and 38 guests