BiPAP vs auto

[Tired Guy]

OK... I've read the "Our Wisdom" and viewed the videos and am beginning to understand (or remember) much of this.

What I don't understand is the BiPap vs Auto issue. From what I have read and watched, it would seem to me that the auto adjusting where you get only the breadth you "need" would be far superior than Bi-level where it is "merely" one pressure of inhalation and one for exhalation.

So.... why the heck are the Bi-level machines 2X the cost of the Auto ones? Everything I know about "more complex" and "better" means that they cost more.

What am I missing? it is not so much the pricing that I am wondering about... it is just that it seems to imply I have something significantly wrong in my analysis!

Thanks again... and before I forget... thanks much to those that took so much time to write and edit the "Our Wisdom" section.

[dsm]

The Auto actually delivers one pressure but varies that one pressure in the hope it can keep it as low as possible& only needs to raise it when the auto thinks events are looming. BUT it never raises pressure quickly (takes minutes ). The theory of Autos is great, the practical application has very mixed results for people. A lot of the failures with autos are when ignorant DME & RTs send the patient out the door with pressure min & max set wide open.

The Bipap (Vpap Bilevel) delivers 2 pressures. The inhale pressure to better deal with OSA & the exhale pressure to make it feel easy to breathe against (vs the auto staying at the same pressure for inhale exhale). An Auto with CFlex tries to help by providing a simulated momentary bilevel pressure - a short dip immediately exhale starts. But a real bilevel does the job properly.

A bilevel (Bipap etc:) with Auto feature, varies both the inhale & exhale pressures. Many folk with Bipap Auto machines & Vpap Auto machines, claim they have the best of everything & seem to be among our happiest users. But they are as you pointed out, dearer (but the gap is closing a bit).

DSM

[jnk]

OK... I've read the "Our Wisdom" and viewed the videos and am beginning to understand (or remember) much of this.

What I don't understand is the BiPap vs Auto issue. From what I have read and watched, it would seem to me that the auto adjusting where you get only the breadth you "need" would be far superior than Bi-level where it is "merely" one pressure of inhalation and one for exhalation.

So.... why the heck are the Bi-level machines 2X the cost of the Auto ones? Everything I know about "more complex" and "better" means that they cost more.

What am I missing? it is not so much the pricing that I am wondering about... it is just that it seems to imply I have something significantly wrong in my analysis!

Thanks again... and before I forget... thanks much to those that took so much time to write and edit the "Our Wisdom" section.

Well, I found it all very confusing myself, so I'm glad you asked.

A CPAP that is not an auto basically gives one straight pressure all night.

An auto CPAP (or, APAP) varies the pressure overnight according to what pressure is needed (that's the theory, anyway).

A bilevel (or biPAP) that is not an auto alternates between two set pressures, one for breathe-in and one for breathe-out, all night.

An auto-bilevel not only has different pressures for breathing in and breathing out but also varies those pressures overnight.

What makes it complicated is that CPAPs with pressure relief (like EPR or flex) sort-of have different pressures for breathe-in and breathe-out too, in imitation of what a bilevel feels like. It just isn't quite the same as bilevel. It is, in a sense, a cheaper version of bilevel. Bilevels are more expensive because of the way they are made to truly give two completely different pressures for breathe-in and breathe-out.

What also makes it confusing is that auto CPAPs can also be run in regular, non-auto, CPAP mode.

Does that muddy the waters enough?

[Tired Guy]

Thanks for responding.... I think both of your answers together solved the mystery.

Here is my take, pls let me know if I "got it"

1) IF Autos really worked, then my original theory would be correct and they would (theoretically at least) be more expensive. Howwever, there is much to be desired in the efficacy of these machines.

2) Bi-level is the same as Bi-Pap (?) and does the lower pressure on exhale higher in inhale thing.

3) There is a newer (maybe) version of Bi-level that is ALSO Auto... but (a) this time Auto with bi-level and (b) it would appear to actually work!

So... not knowing the results of my sleep study or anything else...just going by what works for others (that is my starting point..not my end point) .... my goal should be a bi-level with Auto-- until my doctor and insurance company tells me otherwise!!

[jnk]

Thanks for responding.... I think both of your answers together solved the mystery.

Here is my take, pls let me know if I "got it"

1) IF Autos really worked, then my original theory would be correct and they would (theoretically at least) be more expensive. Howwever, there is much to be desired in the efficacy of these machines.

2) Bi-level is the same as Bi-Pap (?) and does the lower pressure on exhale higher in inhale thing.

3) There is a newer (maybe) version of Bi-level that is ALSO Auto... but (a) this time Auto with bi-level and (b) it would appear to actually work!

So... not knowing the results of my sleep study or anything else...just going by what works for others (that is my starting point..not my end point) .... my goal should be a bi-level with Auto-- until my doctor and insurance company tells me otherwise!!

1. Well, autos do work, and work well for some people. But they are often advertised as working without being customized to the patient. Most here who have posted on the subject have found that the minimum pressure of the auto needs to be within a cm or two of whatever pressure was found to work on titration night for a patient.

Cost is another matter. Cost is more a matter of what the market will allow. When autos were new technology they were very expensive. They are more common now. An auto is always capable of running in straight CPAP mode so you will never really take a hit on efficacy getting an auto, from that standpoint.

2. BiPAP is simply Respironics' name for bilevel. Bilevels give truly separate pressures for breathe-in and breathe-out.

3. Auto-bilevel is fairly new. But auto-bilevels have the same issues as auto-CPAP as far as not working well set up "wide open." The minimum EPAP still needs to be set up within a few cm of titrated EPAP pressure from a bilevel titration. An auto-bilevel machine is the 'latest and greatest' in some ways, but a doctor may not want to prescribe bilevel unless he feels he can prove to insurance you need it. A doctor is unlikely to prescribe a bilevel unless the tech that did the titration gathered evidence you need more than 15 cm or gathered evidence that you need bilevel for some other reason.

That is only how I understand it. I have been known to be wrong on more than one occasion, or so my wife tells me.