[Pressure] Change Pressure on AirCurve 10 VAuto

[_cy_]

yup aircurve 10 vauto sure has a lot of settings ..

unlike Respironics BiPAP Auto which adjusts ipap and epap independently. Aircurve 10 vauto only adjusts ipap with epap determined by PS setting.

max ipap and min epap are set in clinical mode. which set limits Aircurve 10 operates within. example say max ipap is set to 19 with PS set to 4 .. but aircurve 10 determine only 11.8 is needed. then aircurve 10 vauto will operate at: ipap 11.8 / epap 7.8 .. PS sets the spread between ipap and epap. if PS is 4.0, then spread will be 4.0. if say you need epap to be higher or 8.8 in above example .. then PS needs to be changed to 3.

The Aircurve 10 Vauto sets the EPAP to splint the airway and the IPAP is then determined by IPAP=EPAP+PS.

aircurve 10 vauto will track your Ti max and Ti min which is number of seconds your breathing cycle takes. during rampup if you will experiment with Ti max settings. you will notice air delivered during ipap will take longer or shorter. then Aircurve 10 Vauto is adjusting ipap duration to match natural breathing with Ti max setting limits. so aircurve 10 vauto allows pressure adjustment for ipap/epap and duration of ipap by changing Ti max settings.

behavior of Ti max settings were arrived at by increasing/decreasing Ti during rampup and tracking what Ti max actually changed.

The Aircurve 10 Vauto does not change the Ti max or the Ti min. These are static settings which limit the amount of time for the user to cycle from IPAP to EPAP.

If the Ti min is set to 0.3 and the user starts to exhale 0.2 seconds after the the start of inhalation, the machine will remain in IPAP until the 0.3 second mark has been reached.

Conversely, if the Ti max is set at 2.0 and the user has not started to exhale 2.0 seconds after the beginning of the inhale, the machine will drop to the EPAP that the machine is currently using.

Best Regards,

PaytonA

gotta disagree above statement .. it's my understanding that Aircurve 10 Vauto sets ipap only then PS setting determines support pressures by setting pressure difference between ipap and epap.

it would make less sense for A10 Vauto to change epap + PS vs changing ipap less PS .. both technically would work .. be interesting to find out who is correct.

yes Ti max and Ti min are static settings that sets limits .. didn't realize my statements above implied otherwise.

[PaytonA]

yup aircurve 10 vauto sure has a lot of settings ..

unlike Respironics BiPAP Auto which adjusts ipap and epap independently. Aircurve 10 vauto only adjusts ipap with epap determined by PS setting.

max ipap and min epap are set in clinical mode. which set limits Aircurve 10 operates within. example say max ipap is set to 19 with PS set to 4 .. but aircurve 10 determine only 11.8 is needed. then aircurve 10 vauto will operate at: ipap 11.8 / epap 7.8 .. PS sets the spread between ipap and epap. if PS is 4.0, then spread will be 4.0. if say you need epap to be higher or 8.8 in above example .. then PS needs to be changed to 3.

The Aircurve 10 Vauto sets the EPAP to splint the airway and the IPAP is then determined by IPAP=EPAP+PS.

aircurve 10 vauto will track your Ti max and Ti min which is number of seconds your breathing cycle takes. during rampup if you will experiment with Ti max settings. you will notice air delivered during ipap will take longer or shorter. then Aircurve 10 Vauto is adjusting ipap duration to match natural breathing with Ti max setting limits. so aircurve 10 vauto allows pressure adjustment for ipap/epap and duration of ipap by changing Ti max settings.

behavior of Ti max settings were arrived at by increasing/decreasing Ti during rampup and tracking what Ti max actually changed.

The Aircurve 10 Vauto does not change the Ti max or the Ti min. These are static settings which limit the amount of time for the user to cycle from IPAP to EPAP.

If the Ti min is set to 0.3 and the user starts to exhale 0.2 seconds after the the start of inhalation, the machine will remain in IPAP until the 0.3 second mark has been reached.

Conversely, if the Ti max is set at 2.0 and the user has not started to exhale 2.0 seconds after the beginning of the inhale, the machine will drop to the EPAP that the machine is currently using.

Best Regards,

PaytonA

gotta disagree above statement .. it's my understanding that Aircurve 10 Vauto sets ipap only then PS setting determines support pressures by setting pressure difference between ipap and epap.

it would make less sense for A10 Vauto to change epap + PS vs changing ipap less PS .. both technically would work .. be interesting to find out who is correct.

yes Ti max and Ti min are static settings that sets limits .. didn't realize my statements above implied otherwise.

The EPAP is what splints the airway open and prevents OAs. Why would Resmed adjust the IPAP to prevent OAs when the machine spends most of it's time in EPAP. The auto ASV models of VPAP use EPAP to control OAs and the variable PS to control CAs. Read your clinicians manual carefully and analytically and you will find out that this is true.

As far as the Ti max and Ti min is concerned apparently I misinterpreted what you were saying. It sounded like you were saying that the machine was changing the Ti settings.

Concerning the Ti min and Ti max you said, "aircurve 10 vauto will track your Ti max and Ti min which is number of seconds your breathing cycle takes." Ti min and Ti max is not the "number of seconds your breathing cycle takes". It affects the window of time for you to spontaneously cycle your breath from IPAP to EPAP. Otherwise the machine will attempt to help you along by cycling the pressure anyway.

Best Regards,

PaytonA

[_cy_]

The Aircurve 10 Vauto sets the EPAP to splint the airway and the IPAP is then determined by IPAP=EPAP+PS.


The Aircurve 10 Vauto does not change the Ti max or the Ti min. These are static settings which limit the amount of time for the user to cycle from IPAP to EPAP.

If the Ti min is set to 0.3 and the user starts to exhale 0.2 seconds after the the start of inhalation, the machine will remain in IPAP until the 0.3 second mark has been reached.

Conversely, if the Ti max is set at 2.0 and the user has not started to exhale 2.0 seconds after the beginning of the inhale, the machine will drop to the EPAP that the machine is currently using.

Best Regards,

PaytonA

gotta disagree above statement .. it's my understanding that Aircurve 10 Vauto sets ipap only then PS setting determines support pressures by setting pressure difference between ipap and epap.

it would make less sense for A10 Vauto to change epap + PS vs changing ipap less PS .. both technically would work .. be interesting to find out who is correct.

yes Ti max and Ti min are static settings that sets limits .. didn't realize my statements above implied otherwise.

The EPAP is what splints the airway open and prevents OAs. Why would Resmed adjust the IPAP to prevent OAs when the machine spends most of it's time in EPAP. The auto ASV models of VPAP use EPAP to control OAs and the variable PS to control CAs. Read your clinicians manual carefully and analytically and you will find out that this is true.

As far as the Ti max and Ti min is concerned apparently I misinterpreted what you were saying. It sounded like you were saying that the machine was changing the Ti settings.

Concerning the Ti min and Ti max you said, "aircurve 10 vauto will track your Ti max and Ti min which is number of seconds your breathing cycle takes." Ti min and Ti max is not the "number of seconds your breathing cycle takes". It affects the window of time for you to spontaneously cycle your breath from IPAP to EPAP. Otherwise the machine will attempt to help you along by cycling the pressure anyway.

Best Regards,

PaytonA

yes epap provides the splint that keeps passages open and controls OA's. but what we are discussing is if A10 Vauto uses epap or ipap to control auto settings. either one can technically be used, my conclusion was arrived at by changing PS and observing what happens.

for example my ipap is 11.8 with 7.8 epap using a PS of 4. changing PS to say 5 results in A10 Vauto still delivering 11.8 ipap with 6.8 epap with PS of 5. in other words the ipap stayed the same when PS was changed along with epap. to me this is evidence A10 Vauto uses ipap and PS to control auto settings ... not epap.

have searched up and down in the clinical manual and cannot find anywhere it states epap is used to control auto settings. sure would appreciated if you could provide the page number.

on the topic of A10 Aauto tracking your actual Ti .. sorry about not being more clear. A10 Vauto will track your actual Ti .. which for me is 1.4 sec when my max Ti setting is 2.0 (Ti = seconds A10 spends in ipap)

[_cy_]

on another note .. experimenting with higher PS was to lower epap and hopefully reduce air pumped into stomach. changing PS to 5 from 4 did indeed stop air from being pumped into stomach .. lower pressure support increases number of OA events. next changed PS to 4.4 which seems to help keep air from going into stomach. but number of events went to 3 from 1.4. will try 4.2 PS settings next to see if that small PS change will control air into stomach.

[PaytonA]

yes epap provides the splint that keeps passages open and controls OA's. but what we are discussing is if A10 Vauto uses epap or ipap to control auto settings. either one can technically be used, my conclusion was arrived at by changing PS and observing what happens.

for example my ipap is 11.8 with 7.8 epap using a PS of 4. changing PS to say 5 results in A10 Vauto still delivering 11.8 ipap with 6.8 epap with PS of 5. in other words the ipap stayed the same when PS was changed along with epap. to me this is evidence A10 Vauto uses ipap and PS to control auto settings ... not epap.

I guess that I am getting old and easily confused. If you set min EPAP to 7.8 and max IPAP to 11.8 and PS to 4.0 there is no movement possible by the machine. Now if you manually change PS to 5.0. I assume that you are saying that the machine changes the min EPAP to 6.8. Am I reading this correctly so far? My Resmed auto bilevel will not allow me to set PS any higher than 4.0 if my max IPAP and min EPAP are 4.0 apart. I just tried it.

have searched up and down in the clinical manual and cannot find anywhere it states epap is used to control auto settings. sure would appreciated if you could provide the page number.

First there is no place that I can find where it states, "The machine adjusts EPAP to reduce OAs and the IPAP follows as set by IPAP=EPAP + PS". I also can not find the original statement that I thought I remembered but here is what it does say.

"The inspiratory positive airway pressure (IPAP, or the sum of EPAP and the pressure support level)
assists inspiration.
The lower expiratory positive airway pressure (EPAP) facilitates exhalation comfort while providing a
splint to maintain an open upper airway"

This is on page 4 of the clinician's manual. This may not be as definitive as you would like but I do not see why one would not chose to control the parameter that performs the work the machine is supposed to do.

The single pressure auto machines work the other way around because they do not have an EPAP setting. So they set the IPAP to control the events and the EPR reduces the pressure on exhalation for comfort.

on the topic of A10 Aauto tracking your actual Ti .. sorry about not being more clear. A10 Vauto will track your actual Ti .. which for me is 1.4 sec when my max Ti setting is 2.0 (Ti = seconds A10 spends in ipap)

My Ti is about the same.

Best Regards,

PaytonA

[_cy_]

I guess that I am getting old and easily confused. If you set min EPAP to 7.8 and max IPAP to 11.8 and PS to 4.0 there is no movement possible by the machine. Now if you manually change PS to 5.0. I assume that you are saying that the machine changes the min EPAP to 6.8. Am I reading this correctly so far? My Resmed auto bilevel will not allow me to set PS any higher than 4.0 if my max IPAP and min EPAP are 4.0 apart. I just tried it.

on my A10 Vauto: max ipap is set to 14.8 .. min epap is set to 4
with PS set at 4 .. A10 Vauto selects 11.8 ipap / 7.8 epap for me.

with nothing else changed except for PS to 5 .. A10 Vauto now selects 11.8 ipap / 6.8 epap.

ipap remains the same when PS is changed with epap lowered by raising PS .. epap raised by lowering PS

above behavior indicates A10 Vauto adjusts ipap to set epap levels, using PS to control spread and final epap pressures.

my A10 Vauto allows me to change PS from 0.0 to 10.0

[vsheline]

on another note .. experimenting with higher PS was to lower epap and hopefully reduce air pumped into stomach. changing PS to 5 from 4 did indeed stop air from being pumped into stomach .. lower pressure support increases number of OA events. next changed PS to 4.4 which seems to help keep air from going into stomach. but number of events went to 3 from 1.4. will try 4.2 PS settings next to see if that small PS change will control air into stomach.

Hi _cy_

I think all sorts of things might affect our tendency to swallow air, including sleep position, how close our chin is to our chest, the angle of the neck, tension, perhaps diet, as well as chance and of course pressure settings.

I suppose it may be helpful to keep a sleep journal and note our observations for a couple weeks while toggling between two adjustments, to carefully gather reproducible statistics on how a PS adjustment has affected our tendency to swallow air.

on my A10 Vauto: max ipap is set to 14.8 .. min epap is set to 4
with PS set at 4 .. A10 Vauto selects 11.8 ipap / 7.8 epap for me.

with nothing else changed except for PS to 5 .. A10 Vauto now selects 11.8 ipap / 6.8 epap.

ipap remains the same when PS is changed with epap lowered by raising PS .. epap raised by lowering PS

above behavior indicates A10 Vauto adjusts ipap to set epap levels, using PS to control spread and final epap pressures.

Interesting discussion.

During bilevel titrations in sleep labs, EPAP is adjusted to eliminate apneas. This makes sense because the time when we are most susceptible to having apneas start is during EPAP, right after our exhalation has ended. PS is adjusted to eliminate hypopneas and snoring and RERAs (which are caused by Flow Limitation). Flow Limitation, by definition, is something which occurs only during inhalation.

As an example of how the ResMed bilevel Auto adjusts the pressure, if we were to have a long obstructive apnea (and even if there had been no sign of Flow Limitation or snoring) in response I think the ResMed bilevel Auto machine would adjust the EPAP and IPAP pressures higher by the same amount (as long as this would not cause IPAP to be raised higher than Max IPAP).

You have helped us to understand that the behavior of the ResMed software appears to be that IPAP is calculated first, and EPAP is derived from IPAP. Thanks for pointing that out.

So, for example, when Flow Limitation is high enough to warrant increasing the pressure, the machine won't raise EPAP and then calculate IPAP using the formula IPAP = EPAP + PS, instead it will raise IPAP and then calculate EPAP using the formula EPAP = IPAP - PS.

I suppose it may be a distinction without a difference (whether the ResMed bilevel Auto machine first raises EPAP or first raises IPAP), because whenever the machine makes automatic adjustments both EPAP and IPAP will always be raised (or lowered) together by the same amount.

Please note that the Philips Respironics BiPAP Auto may at times behave differently than this, because EPAP and PS may adjust themselves separately and also because increases in EPAP have priority and may cause reductions in PS. The PR BiPAP Auto has behavior which makes me think its IPAP is calculated from its EPAP and PS.

Personally, when explaining how pressure settings are adjusted on bilevel machines, I will explain that, conceptually, EPAP is adjusted to control apneas, and IPAP is adjusted to control Flow Limitation and snoring.

And whoever may be interested in the details can be referred to the full guidelines:
http://www.aasmnet.org/resources/clinica...040210.pdf

[_cy_]

if a design feature for bilevel machine is to deliver minimum amount of pressure and no more. auto titration (Vauto) keying off ipap when max pressure occurs makes the most sense.

For me switching from a straight CPAP Resmed S8 Escape to Philips Respironics auto Bipap (bilevel) greatly reduced pressures in auto mode. Then switched to Aircurve 10 Vauto (bilevel) in auto mode reduced pressures yet again and much quieter.

still getting used Apnea Board's settings .. for detailed posts it's not unusual for me to go back and edit mistakes and/or clarify statements 10+ times. time allowed to edit posts is the shortest I've come across.

[_cy_]

continuation of above post #18 concerning reduction of air pressures switching from straight CPAP Resmed S8 Escape to Philips Respironics auto Bipap (bilevel) greatly reduced pressures in auto mode. Then switched to Aircurve 10 Vauto (bilevel) in auto mode reduced pressures yet again.

as an explanation: note these pressures are for me .. yours could be completely different.

with straight cpap .. I experimented with all different pressures to arrive at an effective splint pressure but not be so high that I could not exhale uncomfortably. which was 6 to 8 range, much below 6 not enough pressure to provide support, over 8 I could not exhale comfortably. since machine I was using Remed S8 has no data, I had to go by how I felt in the AM.

next machine was Philips Respironics auto Bipap (bilevel) ..

[_cy_]

on another note .. experimenting with higher PS was to lower epap and hopefully reduce air pumped into stomach. changing PS to 5 from 4 did indeed stop air from being pumped into stomach .. lower pressure support increases number of OA events. next changed PS to 4.4 which seems to help keep air from going into stomach. but number of events went to 3 from 1.4. will try 4.2 PS settings next to see if that small PS change will control air into stomach.

Hi _cy_

I think all sorts of things might affect our tendency to swallow air, including sleep position, how close our chin is to our chest, the angle of the neck, tension, perhaps diet, as well as chance and of course pressure settings.

thanks .. have already been trying all sorts of different positions with no change .. chin up/down, one soft pillow or two, one hard pillow, large down comforter stuffed into a large bag, etc. etc.

since I'm getting Aerophagia or gas in Stomach with CPAP intermittently .. conclusion is one or both my esophageal sphincters are weak and/or have not yet adjusted to pressurized air.

specific to A10 Vauto .. I've made changes to PS from default 4 to 4.4 .. which will reduce epap pressures without increasing number of events per hour too much. found out it's important not to change pressures too far from default settings .. as that greatly increases number of events per hour. going from 0 events to say 1.5 events to prevent air from going into stomach is on track.

I've also changed Ti from default 2 to 2.2 seconds .. this helps with getting enough air with breathing cycles with lower pressures.

reducing epap pressures slightly seems to have stopped Aerophagia or gas in Stomach with CPAP.