With GERD, is BiPAP superior to APAP reducing aerophagia?

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
-SWS
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Post by -SWS » Sat May 05, 2007 9:31 am

blarg wrote:Have you seen gravity?
What? Admit that and take up residence in a padded room somewhere? No thanks.

I might have seen gravity once or twice. Why do you ask??

PeaceSleeper- CONGRATS!!!!!!!!

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rested gal
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Re: Auto BiPAPs

Post by rested gal » Sat May 05, 2007 10:06 am

PeaceSleeper wrote:There also seems to be some light with a sleep doc in Toronto about monitoring OSA patients much more closely. A doc there is thinking about starting a service---of course in cahoots with ResMed, to pull data from patient's machine weekly for assessment and possible action. Of course, the manufacturers want some of that service bureau revenue so it will be a slow process, but at least someone is moving in the right direction.
Interesting, because for a long time I've thought that when doctors prescribe a temporary auto-titrating trial with ANY autopap for a person to use at home, they (the doc, DME, SOMEBODY) ought to do a download within the first few days and EVERY WEEK thereafter. Just to see how things are going -- especially the leak rate -- but also to see if the typical "wide open" setting they prescribe needs to be changed. Tweaks during the trial could make the trial produce much more useful info, imho.

Giving people an autopap trial wide open at 4 - 20 or even 5 - 20 for a month without looking at what's going on has always seemed...well, stupid...to me. Someone needs to be looking at the "daily details" every week during a trial, imho. Before the older details get overwritten with new.

If the trial is with a PB 420E autopap, it's even more important (imho) that the first download be looked at within a couple of nights, to see whether IFL1 might need to be turned off.

Thanks for the info, PeaceSleeper!
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Re: An update on this post from the initiator.

Post by dsm » Sat May 05, 2007 3:03 pm

PeaceSleeper wrote:Hi All!

Wow, what fun this post started rolling! I have certainly learned even more about respiratory physiology than I planned on.

I am now over a week on my nifty auto BiPAP M series and have given up on the auto titrating function because it definitely wants to push my EPAP up until I start experiencing centrals, no matter what the settings or PSMax.

When I set the unit to IPAP 10.5 cm and EPAP 4.5 cm, my AHI goes consistently below 3 with almost no OAs. In fact, I think the OAs it is reading are just me swallowing or clearing my throat---though I guess those are supposed to be VS events.

Now remember, I was titrated at a reputable sleep lab on bilevel and 10/5 but was not fortunate enough to have the support and help of the kind folks on this forum. I had a super leaky mask and a humidifier that put out way too much H2O to make my asthma do anything but become more reactive. That was 5 years ago and I have been suffering high blood pressure and daily severe headaches since then.

With the help of lots of coaching and knowledge from the forum, I have been able to get my leaks under control, move to a machine that I am quite comfortable using for 6 or 7 hours, and have basically almost no events on a good night.

I just wanted to say---please keep up the discussion, my hope is that people will focus on the issues, and know that you are having a positive impact. Bravo!

Peace

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): bipap, humidifier, AHI, auto


PeaceSleeper,

Welcome to the xPAP success club. MY bet is you won't look backwards & with the CMS settings you are using, I believe little can go wrong but a lot will go right.

The only remaining challenge is leaks & squeaks from the mask but that is a separate issue.

DSM

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NightHawkeye
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Post by NightHawkeye » Sat May 05, 2007 5:19 pm

-SWS, my apologies for taking so long to respond. I started a response this morning, but was called away, and couldn't get back to it until this evening.
-SWS wrote:
NightHawkeye wrote: My understanding is that EPR simply reduces pressure on exhale while leaving the inhalation pressure or IPAP unchanged.

EPR is simply a BiPAP function, is it not?
Bill, unlike traditional BiLevel, Resmed's EPR algorithmically attempts to "handle events". Specifically, Resmed's EPR tries to suspend lowering pressure during EPAP phase for obstructive apneas.
-SWS. after reading your response, I was curious to learn more and here's some of what I found on ResMed's website:
ResMed website wrote:How does EPR work?

When the patient exhales, the S8 flow generator detects the beginning of exhalation and reduces motor speed to drop pressure. The patient or clinician chooses one of three comfort levels to determine the degree by which pressure will drop.

Setting 1 = mild comfort (1 cm H20)
Setting 2 = medium comfort (2 cm H20)
Setting 3 = maximum comfort (3 cm H20)
Clearly, this is Bi-Level functionality. They go on to say that EPR will be turned OFF during detected apneas, as you indicated, after 15 seconds.
ResMed website wrote:EPR Timeout

If a patient's exhalation period exceeds 15 seconds, EPR immediately suspends. The treatment pressure reverts to set CPAP and remains suspended until the next inhalation phase is detected. EPR helps patients experience the highest level of comfort and benefit from their therapy. EPR is available on ResMed S8 EliteTM and the S8 AutoSet VantageTM flow generators.
Blarg, I suppose this last one is what confused you about the duration of EPR. Unlike C-flex, EPR is not a transient phenomenon. Instead, EPR is exactly Bi-level operation. It turns OFF on occasion, as -SWS indicated, but that only happens if apneas, hypopneas, etc are detected.
-SWS wrote:Quite a few patients can get away with traditional BiLevel EPAP being less than CPAP. But quite a few cannot. That last epidemiological reality is why a BiLevel PSG is so often considered "medically prudent" when switching from CPAP to traditional BiLevel.
I believe your statement is awfully heavy-handed there, -SWS. Everything I've read on the matter (excepting Snoredog's unsubstantiated self-serving proclamations) are that Bi-Level (BiPAP) therapy for most folks results in substantially reduced pressure requirements. Here, for instance, is a nearly 20 year old study in the medical journal, Chest (conducted by Respironics), which concludes:
Chest, Vol 98, 317-324, Copyright © 1990 by American College of Chest Physicians wrote: . . . we have shown that by using a device that permits independent adjustment of EPAP and IPAP, obstructive sleep-disordered breathing can be eliminated at lower levels of expiratory airway pressure compared with conventional nasal CPAP therapy. This may reduce the adverse effects associated with nasal CPAP therapy and improve long-term therapeutic compliance.
Here's the link for anyone interested in reading the original.
http://www.chestjournal.org/cgi/content ... f_ipsecsha

The preponderance of evidence seemingly indicates that Bi-Level therapy results in a significant overall reduction in pressure requirements for the vast majority of CPAP patients.
-SWS wrote:Bill, while I have your ear would you mind sharing perceptions? I have always suffered from silent GERD (no perception of my GERD symptoms). I also don't perceive much difference among those various C-Flex settings---aside from increased aerophagia when I have C-Flex turned on. Curious---how does that compare with what you're experiencing?
Actually, -SWS, I haven't associated C-flex with aerophagia at all. I'm not saying there's not a relationship, just that if there is a connection, it hasn't been of major concern to me. As for the silent GERD, I'm of the opinion that while my own GERD didn't present me with the common "burning" stomach acid sensations, it nevertheless has become more obvious to me recently that there have been more subtle sensations of discomfort which I could have been paying attention to if the problem hadn't been so chronic. (not sure that answers your query at all, -SWS, but that's my experience.)

Regards,
Bill

P.S. Congratulations, PeaceSleeper on your renewed success with therapy.


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Post by roster » Sat May 05, 2007 5:56 pm

[quote="NightHawkeye"] ..............As for the silent GERD, I'm of the opinion that while my own GERD didn't present me with the common "burning" stomach acid sensations, it nevertheless has become more obvious to me recently that there have been more subtle sensations of discomfort which I could have been paying attention to if the problem hadn't been so chronic. .....

Rooster
I have a vision that we will figure out an easy way to ensure that children develop wide, deep, healthy and attractive jaws and then obstructive sleep apnea becomes an obscure bit of history.https://www.youtube.com/watch?v=0ycw4uaX ... re=related

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Post by rested gal » Sat May 05, 2007 7:39 pm

NightHawkeye wrote:EPR is exactly Bi-level operation. It turns OFF on occasion, as -SWS indicated, but that only happens if apneas, hypopneas, etc are detected.
I don't think one can say "EPR is exactly Bi-level operation" when EPR will be suspended in the presence of more than 15 seconds of no inspiration (inhalation.)

That alone makes it not be "exactly" like a true bi-level machine. A true bi-level, as long as it's not an ST machine with a timed backup rate set, will continue delivering the lower EPAP pressure UNTIL the person begins an inhalation. A non-ST bi-level will never "suspend" that lower EPAP pressure and let a higher pressure (the IPAP) in UNTIL the person begins to inhale. Unlike EPR which will let the higher "regular" cpap pressure in again if enough seconds go by without an inhalation.

The only similarity I see in EPR with bi-level is the fact that EPR's pressure drop lasts throughout the entire exhalation. Other than than, EPR is not "exactly Bi-level operation", imho.
NightHawkeye wrote:
-SWS wrote:Quite a few patients can get away with traditional BiLevel EPAP being less than CPAP. But quite a few cannot. That last epidemiological reality is why a BiLevel PSG is so often considered "medically prudent" when switching from CPAP to traditional BiLevel.
I believe your statement is awfully heavy-handed there, -SWS. Everything I've read on the matter ... are that Bi-Level (BiPAP) therapy for most folks results in substantially reduced pressure requirements.
Bill, I think you are overlooking an extremely important word in what -SWS said. The word is EPAP.
"Quite a few patients can get away with traditional BiLevel EPAP being less than CPAP"

The study you quoted is not at odds (imho) with what -SWS carefully explained. In fact, if you look at the words I'll emphasize in red, the study is talking about precisely what -SWS is talking about... about EPAP being set to eliminate obstructive events.
NightHawkeye wrote:Here, for instance, is a nearly 20 year old study in the medical journal, Chest (conducted by Respironics), which concludes:
Chest, Vol 98, 317-324, Copyright © 1990 by American College of Chest Physicians wrote: . . . we have shown that by using a device that permits independent adjustment of EPAP and IPAP, obstructive sleep-disordered breathing can be eliminated at lower levels of expiratory airway pressure compared with conventional nasal CPAP therapy. This may reduce the adverse effects associated with nasal CPAP therapy and improve long-term therapeutic compliance.
NightHawkeye wrote:The preponderance of evidence seemingly indicates that Bi-Level therapy results in a significant overall reduction in pressure requirements for the vast majority of CPAP patients.
If you're saying that based on the study you quoted, I think you might be connecting the dots wrong on that one, Bill -- but maybe I am. I think the researchers were talking only about "lower levels of expiratory airway pressure."

A regular CPAP titration will likely come up with a higher single pressure to be prescribed than a bi-level's EPAP pressure. The straight cpap pressure has to take care of all events. The bi-level's EPAP pressure has to take care of obstructive apneas only.

A bi-level titration of the same person will likely come up with lower EPAP pressure (to take care of apneas.) But...the higher IPAP pressure (to take care of hypopneas, flow limitations and residual snores) arrived at in a bi-level titration could likely be just as high as what would have been reached in a simple cpap titration.

Makes sense for the researchers to say "This may reduce the adverse effects associated with nasal CPAP therapy and improve long-term therapeutic compliance." A very significant "adverse effect" for many CPAP users is difficulty in breathing out against high pressures.

But the "this" that the researchers are talking about is "lower levels of expiratory airway pressure." Same thing -SWS was talking about.
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Post by Snoredog » Sat May 05, 2007 9:10 pm

rested gal wrote:
NightHawkeye wrote:EPR is exactly Bi-level operation. It turns OFF on occasion, as -SWS indicated, but that only happens if apneas, hypopneas, etc are detected.
I don't think one can say "EPR is exactly Bi-level operation" when EPR will be suspended in the presence of more than 15 seconds of no inspiration (inhalation.)

That alone makes it not be "exactly" like a true bi-level machine. A true bi-level, as long as it's not an ST machine with a timed backup rate set, will continue delivering the lower EPAP pressure UNTIL the person begins an inhalation. A non-ST bi-level will never "suspend" that lower EPAP pressure and let a higher pressure (the IPAP) in UNTIL the person begins to inhale. Unlike EPR which will let the higher "regular" cpap pressure in again if enough seconds go by without an inhalation.

The only similarity I see in EPR with bi-level is the fact that EPR's pressure drop lasts throughout the entire exhalation. Other than than, EPR is not "exactly Bi-level operation", imho.
NightHawkeye wrote:
-SWS wrote:Quite a few patients can get away with traditional BiLevel EPAP being less than CPAP. But quite a few cannot. That last epidemiological reality is why a BiLevel PSG is so often considered "medically prudent" when switching from CPAP to traditional BiLevel.
I believe your statement is awfully heavy-handed there, -SWS. Everything I've read on the matter ... are that Bi-Level (BiPAP) therapy for most folks results in substantially reduced pressure requirements.
Bill, I think you are overlooking an extremely important word in what -SWS said. The word is EPAP.
"Quite a few patients can get away with traditional BiLevel EPAP being less than CPAP"

The study you quoted is not at odds (imho) with what -SWS carefully explained. In fact, if you look at the words I'll emphasize in red, the study is talking about precisely what -SWS is talking about... about EPAP being set to eliminate obstructive events.
NightHawkeye wrote:Here, for instance, is a nearly 20 year old study in the medical journal, Chest (conducted by Respironics), which concludes:
Chest, Vol 98, 317-324, Copyright © 1990 by American College of Chest Physicians wrote: . . . we have shown that by using a device that permits independent adjustment of EPAP and IPAP, obstructive sleep-disordered breathing can be eliminated at lower levels of expiratory airway pressure compared with conventional nasal CPAP therapy. This may reduce the adverse effects associated with nasal CPAP therapy and improve long-term therapeutic compliance.
NightHawkeye wrote:The preponderance of evidence seemingly indicates that Bi-Level therapy results in a significant overall reduction in pressure requirements for the vast majority of CPAP patients.
If you're saying that based on the study you quoted, I think you might be connecting the dots wrong on that one, Bill -- but maybe I am. I think the researchers were talking only about "lower levels of expiratory airway pressure."

A regular CPAP titration will likely come up with a higher single pressure to be prescribed than a bi-level's EPAP pressure. The straight cpap pressure has to take care of all events. The bi-level's EPAP pressure has to take care of obstructive apneas only.

A bi-level titration of the same person will likely come up with lower EPAP pressure (to take care of apneas.) But...the higher IPAP pressure (to take care of hypopneas, flow limitations and residual snores) arrived at in a bi-level titration could likely be just as high as what would have been reached in a simple cpap titration.

Makes sense for the researchers to say "This may reduce the adverse effects associated with nasal CPAP therapy and improve long-term therapeutic compliance." A very significant "adverse effect" for many CPAP users is difficulty in breathing out against high pressures.

But the "this" that the researchers are talking about is "lower levels of expiratory airway pressure." Same thing -SWS was talking about.
I agree, he is misinterpreting the study, I downloaded Bill's study and wasted 10 pages of paper to print it out, still reading and interpreting it, but I agree they are talking about lower levels of "expiratory relief" compared to CPAP which has NONE!

So can you conclusively say that Bipap results in lower mean pressure than CPAP? I said NO in my first response to this thread and I'm sticking to that statement, it hasn't been modified, go back and look.

Even in Bill's referenced study they indicate EPAP plays an important role in the elimination of apnea. How many times have we seen a report here where the patient has all Hypopnea and NO apnea? They probably wouldn't benefit at all with bipap.

I'm glad PeaceSleeper got relief with use of the bipap. But even they admit they had to prevent the machine's EPAP pressure from increasing. AHI may still improve if that AHI was made up of mainly Hypopnea events.

If you are going to "limit" the response of the machine (such as to eliminate aerophagia) by lowering of the EPAP, you also lower the overall minimum splint pressure maintained in the airway. In other words, if you set EPAP minimum to 5cm, then that is what the minimum splint pressure will be. If you move EPAP to 6cm, that is the new splint pressure. That pressure will be maintained throughout the transition period even during transition changes from IPAP to EPAP.

Next look at Resmed's EPR,

Put IPAP in your left hand, EPAP in your right hand (some visual gravity stuff), the left hand is held at constant pressure, the right hand drops on exhale, how much is based upon the EPR setting used. When an apnea is seen, the right hand STOPS dropping, it stays at the same level as the left hand or again becomes straight conventional CPAP or as compared to bilevel machine, an increase in "EPAP pressure" to eliminate the apnea. Hopefully, from any CPAP titration done, the left hand pressure will be high enough to eliminate any apnea seen if not, the person has residual apnea.

But what does EPR do in the presence of Hypopnea? If you are using 3, does it continue to drop EPAP by 3cm when it sees an Hypopnea?

Bill's studies don't matter, it all depends on what type of events were seen and what factors found the CPAP pressure. To concisely conclude that Bilevel results in lower pressure than cpap across the board is misleading at best.

If PeaceSleeper wanted to do a head-to-head comparison, they would enable Auto titration function and let the machine "find" the ideal IPAP and EPAP pressure on its own, I bet if they had a CPAP of 9cm and that finding was based upon apnea or snores events seen, that the machine would find the same values as in the lab. It may only find IPAP needs to go to 11cm since it will always maintain a 2cm PS or delta. But if it took 9cm pressure to eliminate PeaceSleeper's apnea, it would take the same with EPAP. What you don't know is any fudge factors that the lab tech may have put in the assigned cpap pressure. Maybe it only took 8.5cm to do the job and they gave 9cm.

What most people end up doing here:

1. They start on cpap at 9cm (example pressure only).
2. They switch to an autopap see no relief. Why? because the same events seen during their PSG also causes the autopap to drive up pressure, it can be hypopnea, apnea, snores, FL's, doesn't matter machine will increase on all seen.
3. They switch to a Bipap, first few weeks they may leave it in auto Bipap mode, machine again finds it needs to increase pressure. They end up doing the same thing as PeaceSleeper, that is limiting manually what EPAP can do. But AHI indices are most likely going to climb, because you are leaving SDB events untreated.

One could have done the same thing by putting autopap in cpap mode, dropping pressure and using Cflex or by lowering the Auto:max until it only addresses the apnea, or the same thing that EPAP does. Either method will most likely result in a higher AHI. You just have to look at that AHI and aerophagia and pick the lesser of the two evils.

someday science will catch up to what I'm saying...

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Post by NightHawkeye » Sat May 05, 2007 9:18 pm

rested gal wrote:That alone makes it not be "exactly" like a true bi-level machine.
No argument, RG! I believe I noted the differences in detail.
rested gal wrote:Bill, I think you are overlooking an extremely important word in what -SWS said.
Not overlooking it all, RG. -SWS chose his words carefully, as did I. (I am not in disagreement with what -SWS said.) My point was simply that the vast majority of folks, at least according to the studies I've seen, obtain the same level of effective therapy with their machines titrated so that EPAP < CPAP, significantly less, rather than with EPAP = CPAP. I simply have not found any studies indicating to the contrary of the ones I posted.
NightHawkeye wrote:The preponderance of evidence seemingly indicates that Bi-Level therapy results in a significant overall reduction in pressure requirements for the vast majority of CPAP patients.
rested gal wrote:If you're saying that based on the study you quoted, I think you might be connecting the dots wrong on that one, Bill -- but maybe I am. I think the researchers were talking only about "lower levels of expiratory airway pressure."
Indeed, RG, that is exactly what they were saying, and that is exactly the point I have been making. It is also the issue which -SWS keyed in on when he revived this thread. (It occurs to me as I look at this just prior to hitting the send button, that perhaps you misinterpreted what I said above. Note that I never said lower IPAP than CPAP. -my apologies for any clumsy wording.)
rested gal wrote:A regular CPAP titration will likely come up with a higher single pressure to be prescribed than a bi-level's EPAP pressure. The straight cpap pressure has to take care of all events. The bi-level's EPAP pressure has to take care of obstructive apneas only.
I understand that to be your interpretation, RG.
rested gal wrote:A bi-level titration of the same person will likely come up with lower EPAP pressure (to take care of apneas.) But...the higher IPAP pressure (to take care of hypopneas, flow limitations and residual snores) arrived at in a bi-level titration could likely be just as high as what would have been reached in a simple cpap titration.
Only issue I have here is that you seem to imply a BiPAP titration will result in a higher IPAP level than CPAP level. This is not what research shows, RG. The first study I referenced in this thread stated, as I recall, that for 89% of CPAP patients, the IPAP titration value was essentially the same as the CPAP titration value, while the EPAP titration value was only 60% of that. Those are very significant findings, RG. It is not a small difference, but a very large difference. Rather than setting EPAP equal to CPAP as some here claim, researchers found it should be set to only 60% of that value in 89% of patients. In other words, if one is titrated on CPAP at 10 cm, then the researchers found the equivalent BiPAP titration to be 10 cm IPAP, 6 cm EPAP - for most patients.
rested gal wrote:Makes sense for the researchers to say "This may reduce the adverse effects associated with nasal CPAP therapy and improve long-term therapeutic compliance." A very significant "adverse effect" for many CPAP users is difficulty in breathing out against high pressures.
You bet! That 40% reduction in EPAP, without any increase in IPAP, apparently relieves a lot of grief!
rested gal wrote:But the "this" that the researchers are talking about is "lower levels of expiratory airway pressure." Same thing -SWS was talking about.
Yes! On that we are in full agreement, RG.

Regards,
Bill


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Post by rested gal » Sat May 05, 2007 10:43 pm

NightHawkeye wrote:
rested gal wrote:Bill, I think you are overlooking an extremely important word in what -SWS said.
Not overlooking it all, RG. -SWS chose his words carefully, as did I.
Ok, I thought when you said "exactly" you meant "exactly." Glad to see that you didn't exactly mean it when you chose that exact word.
NightHawkeye wrote:(I am not in disagreement with what -SWS said.)
Good. Kind'a sounded like you were when you said, "I believe your statement is awfully heavy-handed there, -SWS." Even with the "wink" included.
NightHawkeye wrote: My point was simply that the vast majority of folks, at least according to the studies I've seen, obtain the same level of effective therapy with their machines titrated so that EPAP < CPAP, significantly less, rather than with EPAP = CPAP.
Agreed, now that you specify "EPAP" instead of talking in general about "a significant overall reduction in pressure requirements for the vast majority of CPAP patients." Thanks for clarifying what you had in mind.
NightHawkeye wrote:
rested gal wrote:A bi-level titration of the same person will likely come up with lower EPAP pressure (to take care of apneas.) But...the higher IPAP pressure (to take care of hypopneas, flow limitations and residual snores) arrived at in a bi-level titration could likely be just as high as what would have been reached in a simple cpap titration.
Only issue I have here is that you seem to imply a BiPAP titration will result in a higher IPAP level than CPAP level.
Not sure what you are taking issue with there or why you think I implied that.

I said that in a bi-level titration IPAP could likely be set just as high as the pressure that would have come out of a regular CPAP titration. I don't see anywhere that I said or implied a bi-level titration would end up with IPAP higher than a CPAP titration would have come up with.

Looks to me like I was saying the same thing as this...
NightHawkeye wrote:The first study I referenced in this thread stated, as I recall, that for 89% of CPAP patients, the IPAP titration value was essentially the same as the CPAP titration value


NightHawkeye wrote:Rather than setting EPAP equal to CPAP as some here claim, researchers found it should be set to only 60% of that value in 89% of patients. In other words, if one is titrated on CPAP at 10 cm, then the researchers found the equivalent BiPAP titration to be 10 cm IPAP, 6 cm EPAP - for most patients.
I have no problem with that. If I were gonna set the machine, I'd probably put the EPAP at 7 in that example...just to be sure.
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Post by dsm » Sun May 06, 2007 2:27 am

rested gal wrote:
NightHawkeye wrote:EPR is exactly Bi-level operation. It turns OFF on occasion, as -SWS indicated, but that only happens if apneas, hypopneas, etc are detected.
I don't think one can say "EPR is exactly Bi-level operation" when EPR will be suspended in the presence of more than 15 seconds of no inspiration (inhalation.)

That alone makes it not be "exactly" like a true bi-level machine. A true bi-level, as long as it's not an ST machine with a timed backup rate set, will continue delivering the lower EPAP pressure UNTIL the person begins an inhalation. A non-ST bi-level will never "suspend" that lower EPAP pressure and let a higher pressure (the IPAP) in UNTIL the person begins to inhale. Unlike EPR which will let the higher "regular" cpap pressure in again if enough seconds go by without an inhalation.

The only similarity I see in EPR with bi-level is the fact that EPR's pressure drop lasts throughout the entire exhalation. Other than than, EPR is not "exactly Bi-level operation", imho.
NightHawkeye wrote:
-SWS wrote:Quite a few patients can get away with traditional BiLevel EPAP being less than CPAP. But quite a few cannot. That last epidemiological reality is why a BiLevel PSG is so often considered "medically prudent" when switching from CPAP to traditional BiLevel.
I believe your statement is awfully heavy-handed there, -SWS. Everything I've read on the matter ... are that Bi-Level (BiPAP) therapy for most folks results in substantially reduced pressure requirements.
<snip>
RG,

Just as some added input, when I was at Resmed collecting my repl S8's I discussed EPR with the sleep specialist (MD). When I explained I had a PB330 that I used mostly & set at 10/13 & that I was interested to know how that compared to EPR, he said I should feel like it was the same as my Bilevel, to all extents & purposes it was a Bilevel. That was when he also said that most people really having to have a Bilevel for COPD or CSR often required large gaps between Ipap & Epapa - he said 8 was normal.

So as far as the Resmed RT was concerned EPR was Bilevel. I do agree that the suspension during detected events makes it a 'different' Bilevel but it is Bilevel.

DSM

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EPAP or IPAP, I say look at compliance and nightly SDB.

Post by PeaceSleeper » Sun May 06, 2007 2:57 am

Since I'm on my second swing at the bat with CPAP/BiPAP, I cannot help but comment that if a patient is not compliant, it doesn't matter what method of airway splinting they are prescribed---because they aren't using it.

I feel, and have no EEG data to back it up, that when I am breathing out against a high pressure level, my little old respiratory center is being pushed toward a central apneic event. It is much more than just "being uncomfortable" with breathing out against say 9-10 cm of pressure which is my titrated CPAP pressure. For me, I am much more likely to either not breath or to breath erratically at a high EPAP level. I only have about 2 weeks of data to support my view, but it is dramatic how the machine observed OA events drop, not rise, when I force the EPAP pressure lower. This is where it would be useful to understand the demographics of the population to know how many people have similar respiratory behavior as my---with low pressure level induced central apneas. For me, an auto machine running with a high upper range of pressure seems potentially a bit dangerous, or at least very annoying when trying to sleep.

So here is my question---with my M series Auto BiPAP, running in auto mode, it would seem it has no way at all of differentiating between an obstructive apnea and a central apnea---and because of that it will keep bumping up the pressure in 0.5 cm increments until it either hits the max limit of its user settings or it sees a time-averaged decrease in the number of events. In my case, I think I saw a decrease in the pressure primarily because I stopped breathing for extended periods of time---which the machine does time and I can observe with James' program that shows average length of apnea. When in auto and my results show higher EPAP pressures during the night, my apneas get longer---so I believe the machine is believing it is treating an OA event when in reality it is a CA event. Does this make sense? And what are the demographics in the population for this behavior, versus what I guess is the more "normal" behavior of almost 100% obstructive events for other people.

And thank you for the many positive and congratulatory posts. I am pretty psyched about it!! When I started, especially when the aerophagia kicked in big time, I thought I was about "toast". Thanks to people sticking with me on this forum, I was able to work quite easily with the sleep doc to get a BiPAP script and the DME has been excellent to work with. And this is in the face of the not often friendly face of Canadian socialized medicine. I find this forum much more useful than some of the other ones in large part because folks here are so willing to take time to contribute. I hope the enthusiasm builds even more, despite some of the setbacks that some of the vendors might create in the future---in an attempt to control the market. Without this forum I would be in a bad way physically and mentally, but now my outlook is pretty darned positive and I know I'm a hose head for life. Wahooooo!

Peace


-SWS
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Post by -SWS » Sun May 06, 2007 3:27 am

NightHawkeye wrote:Indeed, RG, that is exactly what they were saying, and that is exactly the point I have been making. It is also the issue which -SWS keyed in on when he revived this thread.
That's exactly right, Bill. I revived this thread because I felt you were making some key points that were ignored. More in a later post on those two medical studies and even an EPAP=CPAP statement issued by no other than renowned Dr. Rappaport. In short I felt your contributions to this particular topic were too important to get "short-circuited".
dsm wrote: I do agree that the suspension during detected events makes it a 'different' Bilevel but it is Bilevel
At least the design objective of "event handling" makes EPR BiLevel sound inherently safer than traditional BiLevel.

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rested gal
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Re: EPAP or IPAP, I say look at compliance and nightly SDB.

Post by rested gal » Sun May 06, 2007 1:15 pm

PeaceSleeper wrote:Since I'm on my second swing at the bat with CPAP/BiPAP, I cannot help but comment that if a patient is not compliant, it doesn't matter what method of airway splinting they are prescribed---because they aren't using it.
Truer words were never written!
PeaceSleeper wrote:When in auto and my results show higher EPAP pressures during the night, my apneas get longer---so I believe the machine is believing it is treating an OA event when in reality it is a CA event.
I'd guess that if you are having a central and your breathing starts again before the "timer" (so to speak) of the three little pressure nudges is finished, the machine could think it had been working on an obstructive and would mark it as an obstructive.

PeaceSleeper wrote:And what are the demographics in the population for this behavior, versus what I guess is the more "normal" behavior of almost 100% obstructive events for other people.
Good question. Dunno.
PeaceSleeper wrote:Without this forum I would be in a bad way physically and mentally, but now my outlook is pretty darned positive and I know I'm a hose head for life. Wahooooo!
That's how many of us feel...thank goodness for help from the message boards!
ResMed S9 VPAP Auto (ASV)
Humidifier: Integrated + Climate Control hose
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3M painters tape over mouth
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roster
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Post by roster » Sun May 06, 2007 3:08 pm

[quote="NightHawkeye"] ..............As for the silent GERD, I'm of the opinion that while my own GERD didn't present me with the common "burning" stomach acid sensations, it nevertheless has become more obvious to me recently that there have been more subtle sensations of discomfort which I could have been paying attention to if the problem hadn't been so chronic. .....

Rooster
I have a vision that we will figure out an easy way to ensure that children develop wide, deep, healthy and attractive jaws and then obstructive sleep apnea becomes an obscure bit of history.https://www.youtube.com/watch?v=0ycw4uaX ... re=related

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dsm
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Post by dsm » Sun May 06, 2007 4:15 pm

-SWS wrote:
NightHawkeye wrote:Indeed, RG, that is exactly what they were saying, and that is exactly the point I have been making. It is also the issue which -SWS keyed in on when he revived this thread.
That's exactly right, Bill. I revived this thread because I felt you were making some key points that were ignored. More in a later post on those two medical studies and even an EPAP=CPAP statement issued by no other than renowned Dr. Rappaport. In short I felt your contributions to this particular topic were too important to get "short-circuited".
dsm wrote: I do agree that the suspension during detected events makes it a 'different' Bilevel but it is Bilevel
At least the design objective of "event handling" makes EPR BiLevel sound inherently safer than traditional BiLevel.
SWS,

Yes I would have thought so. What I am not certain about with EPR is how agreeable the rise times & switching sensitivity will prove. On the PB330 & Vpap III these params are highly tunable.

I plan to get my hands on an EPR enabled S8 & use it for a while (I lucked out on getting such a model when Resmed replaced my 2 Escape units).

DSM

Doug

xPAP and Quattro std mask (plus a pad-a-cheek anti-leak strap)