What does bipap do that cpap doesn't

[Jackman]

I have been using a Respironics Auto Flex for about the last month plus. Minimum pressure of 4 and maximum of 18. Now, they think I should be using bipap. Just curious of why that would better over the way I have been using it? I have not been shown what the information has been gathered on the machine over the last month.

What is the purpose of bipap? As I understand it, bipap has inhale pressure and exhale pressure, right?

Thanks

[davelikesbeer]

The first time you should do is download your data and see where you stand. A pressure range of 4 to 18 is waaaaay too broad. Well, kind of. The upper pressure will most likely never get met. But if your machine starts at 4 then takes a while to build up to an average pressure of 8 or so, you might want to then consider increasing your starting pressure to something higher. But you really need to look at your data before doing that.

And yes, you are correct. The BiPAP has two different pressures for each breath. One for inhaling and a lower one for exhaling. My doctor put me on BiPAP because she felt my high pressure on my APAP machine wasn't allowing me to exhale fully.

[FizzyWater]

And yes, you are correct. The BiPAP has two different pressures for each breath. One for inhaling and a lower one for exhaling. My doctor put me on BiPAP because she felt my high pressure on my APAP machine wasn't allowing me to exhale fully.

My CPAP machine says it does that (decrease pressure on exhale), too. Is the BiPAP more obvious that the C-flex? (Not being a smart-a$$, just trying to understand the difference).

[Pugsy]

My CPAP machine says it does that (decrease pressure on exhale), too. Is the BiPAP more obvious that the C-flex?

Hugely different. There simply is no comparison.
I have used both CFlex and AFlex. The actual amount of reduction in pressure with these setting choices is very minor.

I am now using PR S1 BiPap Auto but in straight BiPap mode...EPAP 9 cm and IPAP 13. The difference that is perceived is monumental. Hugely more comfortable than APAP 10 minimum is.

[archangle]

BiPap is Respironics trade name for "bilevel PAP". ResMed uses the trademark VPAP for the same thing.

A bilevel machine can set separate pressure for inhale and exhale. The "exhale relief," "Flex," and "EPR" only lower the pressure up to 3 cm between inhale and exhale. Bilevel can do a higher difference between inhale and exhale. Bilevel can set a specific inhale and exhale pressure.

CPAP machines can't go over 20 cmH2O pressure. Bilevel can.

Some bilevel machines have other features such as servo ventilation where it tries to time your breathing to make you take x breaths per minute. These ventilator machines are sort of a step above bilevel, but sometimes they're called bilevel as well.

[turbosnore]

And yes, you are correct. The BiPAP has two different pressures for each breath. One for inhaling and a lower one for exhaling. My doctor put me on BiPAP because she felt my high pressure on my APAP machine wasn't allowing me to exhale fully.

My CPAP machine says it does that (decrease pressure on exhale), too. Is the BiPAP more obvious that the C-flex? (Not being a smart-a$$, just trying to understand the difference).

I jut read somewhere that ResMed (S8 APAP or S9 APAP or both) the EPR (Exhale Pressure Relief, same thin as Respironics' flex)
lower the pressure 1.2 or 3.0 cmH2O depending on the EPR setting.

For a bilevel, the difference can be (this is guessing) set to 4 - 25 cmH2O.
Also, I think they use bilevels also when the centrals are causing trouble in xPAP treatment, or if the patient has UARS.

[cflame1]

I jut read somewhere that ResMed (S8 APAP or S9 APAP or both) the EPR (Exhale Pressure Relief, same thin as Respironics' flex)
lower the pressure 1.2 or 3.0 cmH2O depending on the EPR setting.

Not sure about the Resmed part... but that's not true for Respironics. They don't drop 1, 2 or 3 cm based on the FLEX setting.

[Pugsy]

Respironics exhale relief is not based on pressure reduction like ResMed machines..so not the same animal.
Instead it is flow based. Here is AFlex explanation and the other Flexes in upper right corner links.
http://aflex.respironics.com/ The reduction in pressure during this flow based relief is much smaller reduction even at the setting of 3.

Rested Gal as had a chance to use Respironics AFlex, ResMed EPR and a BiPap machine and all their exhales relief options. She can explain it better but the exhale relief in a BiPap with the range between inhale and exhale is much more dramatic. Pretty much instantaneous and inhale pressure does not start until inhale starts. BiFlex on the BiPaps again is flow based so with Respironics BiPaps there is BiFlex flow based in addition to the dramatic EPAP/IPAP range of settings available on BiPap. She has told me that even resmed EPR at 3 is not the same as a EPAP and IPAP range of 3. She told me it just feels different. I have never had a chance to use a ResMed machine to see for myself.

Also I have found trying the PR S1 BiPap that straight BiPap offers more immediately seen exhale relief while awake and first masking up. In straight Bipap if you set EPAP to 8 and IPAP to 12 you can see the range change on the LCD screen immediately. When using Auto mode the range seen is only 2 cm even though your IPAP might be much larger.
IPAP won't rise till events trigger a rise and one must be asleep for this to happen.
That 2 cm difference perceived when first masking up is not nearly as easy to exhale with as a 4 cm difference in straight BiPap mode.

Strictly from a comfort while awake viewpoint straight BiPap EPAP at 10 and IPAP at 14 or 15 is easier to exhale with
than similar settings in Auto mode because the machine only gives you inhale that is 2 cm higher than EPAP while awake so 10 EPAP and 12 IPAP.. even if IPAP is 20...one only gets the 2 cm pressure support until IPAP is driven upwards by event precursors. Then it will drag EPAP up with it based on your pressure support choices.
Respironics machines allow for variable pressure support in auto mode. I think ResMed VPAPs have a fixed pressure support.

It is the difference between inhale and exhale that gives the perceived comfort with BiLevel therapy. I have a friend using BiPap Pro. Now at 14.5 EPAP and 18.5 IPAP... on cpap she was at 16.5.. she says BiPap is hugely easier to breathe with. A setting of 15.5 EPAP and 17.5 IPAP is simply not nearly as easy to breathe with. It is the difference in the settings that offers the relief.

One must also remember that EPAP must be set at a pressure where the bulk of the OAs are taken care of. One can't have an EPAP that is extremely low an expect it to be completely effective. When it is we run into the same problem as any auto machine has...the time getting EPAP and IPAP to where it needs to be effective.

[robysue]

Rested Gal as had a chance to use Respironics AFlex, ResMed EPR and a BiPap machine and all their exhales relief options. She can explain it better but the exhale relief in a BiPap with the range between inhale and exhale is much more dramatic. Pretty much instantaneous and inhale pressure does not start until inhale starts. BiFlex on the BiPaps again is flow based so with Respironics BiPaps there is BiFlex flow based in addition to the dramatic EPAP/IPAP range of settings available on BiPap. She has told me that even resmed EPR at 3 is not the same as a EPAP and IPAP range of 3. She told me it just feels different. I have never had a chance to use a ResMed machine to see for myself. emphasis added

I too can attest that a System One BiPAP with IPAP - EPAP = 3 feels very very different from an S9 AutoSet with EPR = 3 (with Bi-Flex turned OFF). I'm glad I'm not the only one who can tell the difference.

Also I have found trying the PR S1 BiPap that straight BiPap offers more immediately seen exhale relief while awake and first masking up. In straight Bipap if you set EPAP to 8 and IPAP to 12 you can see the range change on the LCD screen immediately. When using Auto mode the range seen is only 2 cm even though your IPAP might be much larger.

Not sure what you mean here: When I mask up and start my machine, I see this:

EPAP = my min EPAP = 4cm
IPAP = EPAP + 2 = 6cm

And I can tell you that for me, breathing when I'm still awake at the beginning of the night at 6/4 is easier than breathing when I wake up with the pressure at 8/4, which is not that uncommon. But breathing at 8/4 is much, much easier and more natural feeling than breathing on the S9 at 8cm with EPR = 3 ever was for me.

Strictly from a comfort while awake viewpoint straight BiPap EPAP at 10 and IPAP at 14 or 15 is easier to exhale with
than similar settings in Auto mode because the machine only gives you inhale that is 2 cm higher than EPAP while awake so 10 EPAP and 12 IPAP.. even if IPAP is 20...one only gets the 2 cm pressure support until IPAP is driven upwards by event precursors. Then it will drag EPAP up with it based on your pressure support choices.

EPAP only gets "dragged" up by IPAP being increased once IPAP - EPAP = PS.

Respironics machines allow for variable pressure support in auto mode. I think ResMed VPAPs have a fixed pressure support.

That's my understanding too. On the Resmed VPAPs, IPAP and EPAP always increase/decrease at the same time and by the same rate.

[Pugsy]

Not sure what you mean here: When I mask up and start my machine, I see this:

EPAP = my min EPAP = 4cm
IPAP = EPAP + 2 = 6cm

I am using straight BiPap mode and not auto mode EPAP 9 cm and IPAP 13 cm.. 4 cm difference. When I watch the machine it bounces back and forth between 9 and 13.
If I try same settings in Auto mode..EPAP is 9 cm but IPAP just starts out at 11 cm...the 2 cm minimum PS. So it bounces back and forth between 9 and 11. IPAP will of course drag EPAP with it per the PS setting in response to events when I am asleep. That setting doesn't give me the "difference" feeling that I get with the 4 cm difference while awake. It is the "difference" that I have found I like. For me it feels no different than breathing without the machine at all.

I can do EPAP 9 and IPAP at 20 if I wanted which would be like my APAP settings and I did do one night with it that way just to see what it was like. It was fine. No problems. It isn't hard to exhale against 9 at all...I have been using 10 minimum APAP for over 2 years. So in auto mode 9/11 would work fine... I have just found that I happen to like feeling the "difference" that 4 cm or more range in straight bilevel mode gives me. Either will work well while I am asleep I suppose.. I just found I really, really like the 4 cm difference and how smooth and effortless it is. It is actually easier on me than 9 EPAP and 11 IPAP in auto was while awake. Much less work if one wants to call it work.

I have only been doing the BiPap a little over 2 weeks. I plan to start a thread on this experiment soon. I just wanted a little more data. I will say that for the first time since I started CPAP therapy I actually "feel" the good numbers that I have had since I got my pressures tweaked. I was "okay" before on APAP but just "okay"...Since using the BiPap I am averaging an hour more of sleep, husband says I don't move around as much, and I feel hugely more rested the next day. Something in my body likes BiPap and I am going to keep using it.

So essentially I tried using something that felt really great while awake (the wide range in EPAP & IPAP in straight bilevel mode) and stumbled on to something that for some reason has made a huge improvement in how I have felt during the day.

[FizzyWater]

Thanks for the explanations.

It would seem to me that with those greater differences between inhale and exhale could lead to more leaking around your mask, since the pressure isn't more-or-less constant?

Other than those first claustrophic weeks on the machine, I haven't really noticed the pressure on exhaling at all. In fact, some mornings when I wake up, I have to put my hand in front of the mask to see if it's still blowing air (I've gotten so used to it).

Still haven't figured out how to comfortably talk or yawn while wearing the mask either.

Again, thanks for the explanations. It's too bad there isn't a place to try these out that doesn't charge $4000 a night!

[rested gal]

Rested Gal as had a chance to use Respironics AFlex, ResMed EPR and a BiPap machine and all their exhales relief options. She can explain it better but the exhale relief in a BiPap with the range between inhale and exhale is much more dramatic. Pretty much instantaneous and inhale pressure does not start until inhale starts. BiFlex on the BiPaps again is flow based so with Respironics BiPaps there is BiFlex flow based in addition to the dramatic EPAP/IPAP range of settings available on BiPap. She has told me that even resmed EPR at 3 is not the same as a EPAP and IPAP range of 3. She told me it just feels different. I have never had a chance to use a ResMed machine to see for myself. emphasis added

I too can attest that a System One BiPAP with IPAP - EPAP = 3 feels very very different from an S9 AutoSet with EPR = 3 (with Bi-Flex turned OFF). I'm glad I'm not the only one who can tell the difference.

Well... what I've said (Pugsy expressed what I've said correctly) in my comparisons of the feeling (to me) of bilevel vs EPR ... has never been the kind of problem with EPR you've talked about, robysue.

If I recall correctly, your problem with how EPR felt to you was a "tickle" you felt in your throat, making EPR unusable for you.
viewtopic.php?p=606451#p606451

I've never felt a tickle in my throat with EPR. The "just feels different" (from true bilevel) feeling that I get when using a CPAP or AutoPAP with EPR turned on is a distinct feeling of "resistance" when I first start to breathe out each time with EPR, compared to the almost instantaneously complete drop in pressure I get each time I start to breathe out when using a bilevel machine.

Unlike you, I had no problem using EPR...I never felt any "tickle" which is what you've described several times as being your problem with EPR. The difference I feel with a bilevel's way of handling drop in pressure when exhaling is purely a matter of more comfort (for me) at the beginning of each exhalation when using a bilevel machine. Distinctly more comfort (for me) breathing out on a bilevel machine than I get with EPR in a CPAP or autopap.

The way the different types of machines, brands of machines, "comfort" features, etc., feel to each person certainly can be different. You say you're glad you are "not the only one who can tell the difference" between bilevel therapy and cpap/autopap with EPR turned on. However, the specific "difference" you felt when using EPR, robysue, was not at all what I felt with EPR.

I wouldn't be surprised if there are others who would describe a completely different feel with EPR than the two very different ways you and I've experienced it. Perhaps some even prefer the feeling of exhaling with EPR, to the feeling of exhaling with a true bilevel.

To complicate matters further -- there are several people on this forum for whom Respironics (Philips Respironics) "digital tracking" (the way that brand's algorithm determines when the person is still breathing out, pausing, and starting to inhale again) doesn't work well at all to interpret their respiratory cycle. For them it switches up to the higher inhale pressure when they are still trying to breathe out, or can drop to the lower EPAP when they're still trying to breathe in, even though the built in limit of how long IPAP can be delivered has not timed out at all. That doesn't happen to me, and probably doesn't for the majority of people who receive a PR1 BiPAP or PR1 BiPAP Auto, but it does to some. So, even with true bilevel machines, the actual brand (PR1's "BiPAP" or ResMed's "VPAP") can matter as to how bilevel "feels" to them. And, more importantly, how it treats them.

[Kellsie]

I see, I spuopse that would have to be the case.

[fiberfan]

When I started using an apap spring of '10, I quickly found I needed the EPR set to 3, when I dropped the EPR to 2 I would wake more tired. When my asthma got worse early this year, I found the EPR of 3 wasn't enough even with a lowered pressure. In April my doctor agreed to let me try a bi-level as I was only able to use the apap half the time.

Using a bi-level I quickly found that the lowered pressure I was using on the apap was too low for me to breath in comfortably and with the ability to have epap and ipap set as far apart as needed I could have plenty of air pressure on inhale without the tiring exhale against pressure the increased asthma had caused.

There are nights I am tempted to start the bi-level early because breathing in with the increased pressure helps the asthma but since my brain has a nice bi-level means go to sleep connection I have resisted the temptation.

My asthma is moderate at worst but the rescue meds often make me worse so my approach to managing symptoms is a bit different.