Talk To Me About Resmed's VPAP Pressure Support

You may be right about the ResLInk making the difference in the reporting and graphing, jnk!!! I'll be glad when the new SmartMedia cards get here and I can use it again.

Imagination wouldn't make that graph have fluctuations up and down in a jagged line, jnk. And that is what I had early on w/this VPAP Auto.

And tell me this, in the Summary graphs, the Pressure bar graph, is it desirable to have the entire bar at the Median pressure w/no 95th percentile or Maximum shown? 'Cause early on those bars would show Median, 95th Percentile and Maximum. I am assuming this is 'cause I need MORE pressure than the present IPAP setting. I'm sorely tempted to just change her back to the original IPAP 13, EPAP 8 - but it confuses me WHY the Pressure Support was set at 4 then and not the 5 they want now.

Bluebonnet_Gal wrote: . . . Just a note that my pressure is usually not a straight line all night. Some nights, I have a straight line all night, but most nights, there is some slight fluctuation. Since I got my EPAP up to closer to where it needs to be, I see a LOT LESS fluctuation in the pressure through the night.

I would call that a good thing. You used the machine to auto-titrate, then you adjusted the machine to where your pressure needs to be. That meets my definition of success!

Bluebonnet_Gal wrote: Thanks for your explanation Jeff. That makes sense. Thanks for the "plain English" which ResMed doesn't seem to be able to use!

You are welcome. Just remember that what I say is only my personal conclusions on it all. I'm no expert. I hope it helps, though.

Maybe ResMed's wording makes sense to those who speak Australian. *

jeff

* [Note: Please ignore my shameless attempt to start a flame war (or maybe just a spark skirmish) with dsm and his kin. ]

THAT is what "I" am having a problem with. This IS a VPAP "AUTO", WHY are we "by guess and by goshing" w/these pressure settings?? Every now and then I get disgusted and try a few things on my own. BUT it "is" more difficult when you have COPD because sometimes your breathing or your breathing capacity isn't consistent day in and day out. Exacerbations can just creep up on you and you don't recognize them until they become relatively severe. So that is why I TRY to cooperate and not go flying off the handle on my own. And THAT is why when they switched me to a bi-level I insisted on a bi-level auto. I'm about ready to say to h*ll w/this bi-level and pull out my faithful ole S8 AutoSet Vantage.

Slinky wrote:THAT is what "I" am having a problem with. This IS a VPAP "AUTO", WHY are we "by guess and by goshing" w/these pressure settings?? Every now and then I get disgusted and try a few things on my own. BUT it "is" more difficult when you have COPD because sometimes your breathing or your breathing capacity isn't consistent day in and day out. Exacerbations can just creep up on you and you don't recognize them until they become relatively severe. So that is why I TRY to cooperate and not go flying off the handle on my own. And THAT is why when they switched me to a bi-level I insisted on a bi-level auto. I'm about ready to say to h*ll w/this bi-level and pull out my faithful ole S8 AutoSet Vantage.

I hear ya, Slinky. And your COPD is what makes everyone careful about suggesting things, I'm sure. I am no doctor or tech or therapist, so I sure don't have any right to even have an opinion on your situation at all. But my opinion, nevertheless, is that, for you, the pressure support is the most important number. I think that makes the ResMed autobilevel you have the best machine for you. In my opinion, your COPD would make the Respironics autobilevel not as good a choice, so I am glad you ended up with what you have. On the other hand, I wish I could try the Respironics autobilevel, myself, because I have a feeling it might give me better treatment. I don't know, though.

Four is the standard amount of pressure support to start out with when doing bilevel titrations, as I understand present protocol. I don't know if they prescribed pressures with a difference of five cm to you because of your OSA or your COPD. But when they gave you a bilevel prescription, they gave you two specific pressures to use. Translating those two numbers into what should be programmed into an autobilevel is not something anyone in the industry is trained for anywhere, as far as I know. I am still glad you got a cutting-edge machine. In my opinion, the way to use your machine in auto mode is to extrapolate from the two numbers they gave you what pressure support they had in mind. You can either run your machine in bilevel mode at the exact IPAP and EPAP numbers prescribed, or you can run it in auto mode by, most importantly, programming in the distance between the numbers they gave you as your fixed pressure support. In other words, to my way of thinking, when your machine is in auto mode, the most important thing is programming in the pressure support number, which for you is 5.

You can find the right minimum and maximum to use by watching your nightly results. The rest of the settings on your machine are true comfort settings. In my opinion, in your case, pressure support is NOT a comfort setting, regardless of what the manual says. It is written that way because the idea behind autos is that they are designed to treat you comfortably above all else. The idea behind them originally was for us all to run them wide open. But we know here that isn't the best way to get the best treatment from those machines. Also, there is some confusion in the industry, apparently, about the best way to handle pressure support in an autobilevel. But my opinion is that what ResMed is doing in locking in pressure support all night is a good idea for a COPD patient, and makes it prudent enough for you to run it in auto mode as long as your pressure support number is right.

The overall problem, I think, is that you have a very advanced machine that RTs aren't familiar with yet, and you are trying to optimize your therapy in a way that the industry isn't designed to fascilitate. So I understand your frustration with the industry as a whole. But you are doing the right thing in working with it all and figuring it out. It is unfortunate that you are basically on your own in doing that. But with a machine that new, relatively speaking, that's just the way it is and may be for some time.

I hope you don't mind my ramblings and opinion-throwing like that, Slinky. My heart goes out to you, and I wish I had the ability to give a fraction of the support to you that you've given to countless others for so many years.

jeff

. . . I select VPAP (auto). The next thing up is IPAP, I set it at 11 cms. The next thing up is EPAP, I select 6. The next thing up is Pressure Suppot, I set that at 5.

At those settings, the auto will never adjust anything. It has no room.

If you are in auto mode (called VAuto mode), you should be programming in the maximum IPAP and the minimum EPAP, not actual IPAP or actual EPAP. If you want the auto to do any auto-ing, then you'll need to give it a range to work in. You will need to raise your maximum IPAP.

Slinky, I'm trying to pick up (follow up?) on the things Jeff said so beautifully - about you, about your machine and about COPD.

If I understant correctly, a major problem with COPD is breathing out. Healthy lungs have a natural elasticity that lets them shrink and clear CO2 when people are no longer inhaling. Withe COPD (again, if I've understood correctly) the lungs have lost some of their elasticity, and you have to struggle to breath out, using you muscles forcefully. That would explain why they want you on a low EPAP.

While I agree that for healthy people it is often the difference between EPAP and IPAP the helps them breathe comfortably, I'm not at all sure if that's true for COPD. I can imagine a scenario where a person with COPD needs an objectively low EPAP.

dsm wrote:This is what makes more sense to me

Min Epap = 6
Max Ipap = ? (this shd be set to above 11 if you want VAuto to work)
PS = 5 (which sets Ipap = 6+5 being 11)
IF the machine is in VAuto mode AND If the machine detects no events & doesn't shift Ipap then the 95th % pressure should be somewhere between the 2 settings of 5 & 11. I can't see it being stuck at one or the other, it *has* to be just below ipap.

I agree with the above.

But as a side comment PS= 5 goes against my good judgment as a valid setting esp with your Min Epap set as low as it is. I would hope the RT thought very carefully about such a wide spread between epap & ipap when epap is set so low.

I don't understand what's wrong about the spread. If a person with COPD needs help both in breathing in (IPAP) and exceptional support for breathing out (low EPAP) I see nothing wrong with the spread.

Priority is given to the Max IPAP setting, followed by Min EPAP and then
Pressure Support. The device automatically adjusts the lower-priority settings to
ensure the device pressure limits are not exceeded.

Bear in mind that I have never held any kind of bi-level in my hands, let alone set it or breathed with it.

Jeff's explanation about the way the data is presented seems to me to very much to the point.

Note what Jeff said about PS: On a Resmed, the pressure support itself will not vary during the night - once you've set it, its set. And, since your max IPAP is equivalent to EPAP + Pressure Support, then by definition, the pressures won't vary either.

Ok, I see that Jeff has just said the following too, but I'll still keep this in the post:

If you want the machine to vary, for any reason, you would have to change the IPAP to higher. Mind you, I am not saying you should do this, and I am not saying this will giver you better therapy. That is beyond me. I am making a purely technical statement: I you set the IPAP higher, without changing anything else, that I think you may find variablilty through the night.

I assume they want you at PS 5 and not 4 to give you more relief on inhale - its role - is "Pressure Relief" in your case.

O.

ozij wrote:. . . While I agree that for healthy people it is often the difference between EPAP and IPAP the helps them breathe comfortably, I'm not at all sure if that's true for COPD. I can imagine a scenario where a person with COPD needs an objectively low EPAP. . . . O.

Very good points. Thanks for making them, ozij. (I breathed a sigh of relief just seeing that you had made a post in the thread.)

I was making assumptions based on the fact that her two bilevel titrations were different pressures but both reflected 5 cm PS. (And making assumptions with COPD is what I was trying hard not to do.) If I remember, the titration with the higher pressures was earlier than her titration with lower pressures, which may well, indeed, be related to your point. I don't know. Slinky has said in the past that she is not a CO2 retainer.

I wish I knew how to buy Slinky her own personal doc and RT who knew her OSA and COPD situations completely and her machine.

Slinky wrote: You may be right about the ResLInk making the difference in the reporting and graphing, jnk!!! I'll be glad when the new SmartMedia cards get here and I can use it again.

Imagination wouldn't make that graph have fluctuations up and down in a jagged line, jnk. And that is what I had early on w/this VPAP Auto.

Yes. The ResLink gives you a graph literally showing each breath.

Slinky wrote: It confuses me WHY the Pressure Support was set at 4 then and not the 5 they want now. . . .

I assume (here I go with my assumptions again) they left the pressure support in the machine at its default, which is 4, and programmed your prescribed IPAP and EPAP numbers into the maximum IPAP and minimum EPAP slots. That's only my assumption as to why pressure support was at 4 on your machine before, instead of 5.

When my ex-DME brought me my machine after I insisted on an auto, the RT, similarly, had put it in VAuto mode but had programmed in my prescribed pressures as the maximum and minimum. I guess she had to, since the doc had not prescribed any minimum/maximum range on my prescription--he had only given IPAP/EPAP for straight bilevel and then said "patient may use an auto."

The way your machine is set up now, you are using it as a straight bilevel at close to your prescribed pressures but are also getting the comfort of easy-breathe too. Not a bad deal, really. If your overnight numbers are good enough, there may be no reason for you to want your auto to do any auto-ing. The benefit is getting the easy-breathing.

Just a thought.

But the thing of it is there is no Max and Min IPAP (or EPAP for that matter) there is ONLY IPAP and EPAP. And there is absolutely no indication anywhere, software, graphs, details, LCD screen, that ANY pressure but the half way mark of the pressure support is being produced, i.e. at IPAP 11, EPAP 6, Pressure Support there is NO indication this VPAP Auto is producing anything but a straight 8.4 cms of pressure (half of 5 is 2.5, so has to be 2.4) and 2.4 plus the EPAP of 6 is 8.4.

Forgive me, but DARN doctors that DON'T understand possible "comfort settings" and DARN local DME RTs who don't pour over that Clinicians Manual and learn to understand the products they sell. Mumble. Grumble. Cuss. Snarl.

By the way, I appreciate and respect the reasons for not wanting to make pressure recommendations. I'm really not looking for them. What I AM trying to do is understand how this d*mn VPAP Auto works IF it IS working properly. Either this Pressure Support is NOT working as it should, or I am not understanding something in the reporting of the data. GRRRRRRRR! I don't give a rat's rear what the data says once everything is feeling comfortable again like it did before they started tinkering w/it. But for now, that's all I have to work w/: the reported data and how I feel.

Just got a call from the office of my old/new (original) sleep doctor I just switched to (he'd moved an hour away and I stupidly didn't follow him until now). He's upped my IPAP to 13.

ozij wrote: <snip>

But as a side comment PS= 5 goes against my good judgment as a valid setting esp with your Min Epap set as low as it is. I would hope the RT thought very carefully about such a wide spread between epap & ipap when epap is set so low.

I don't understand what's wrong about the spread. If a person with COPD needs help both in breathing in (IPAP) and exceptional support for breathing out (low EPAP) I see nothing wrong with the spread.

>>> My concern would be if Slinky has any OSA compoanent (which I believe is the case) in which case an epap as low as 6 + a big spread tends to exacerbate othe OSA.

Priority is given to the Max IPAP setting, followed by Min EPAP and then
Pressure Support. The device automatically adjusts the lower-priority settings to
ensure the device pressure limits are not exceeded.

Bear in mind that I have never held any kind of bi-level in my hands, let alone set it or breathed with it.

Jeff's explanation about the way the data is presented seems to me to very much to the point.

Note what Jeff said about PS: On a Resmed, the pressure support itself will not vary during the night - once you've set it, its set. And, since your max IPAP is equivalent to EPAP + Pressure Support, then by definition, the pressures won't vary either.


>>>> The way PS works is that it combined with epap Min sets the bilevel pressure operation say PS=4 & epap Min = 8 then IPAP (not Ipap Max) will equal 12. Ipap Max if set above 12 (say 16) sets the upper limit the ipap can float too as events are detected. As ipap floats up in response to events, epap follows at exactly PS CMs below IPAP.

Ok, I see that Jeff has just said the following too, but I'll still keep this in the post:

If you want the machine to vary, for any reason, you would have to change the IPAP to higher. Mind you, I am not saying you should do this, and I am not saying this will giver you better therapy. That is beyond me. I am making a purely technical statement: I you set the IPAP higher, without changing anything else, that I think you may find variablilty through the night.

I assume they want you at PS 5 and not 4 to give you more relief on inhale - its role - is "Pressure Relief" in your case.

>>>> I think Slinky may have been experimenting. Slinky, is that the case ?

O.

In addition.

RE the Respironics Bipap Auto (w biflex) that machine doesn't apply PS the way the Resmed one does. It sets its own default PS of 2 CMs then during the night it will *independantly* vary ipap & epap thus dynamically changes PS on the fly whereas the Resmed PS remains fixed - the Resmed Bipap Auto machine allows the user to set a MAX PS - this is the maximum the epap-ipap gap can float to during the night while events are detected.

Both machines are difficult to explain but easy to visualize once the explanations are understood. In the case of the Resmed just thing of 2 pressures eaxactly PS apart & these 2 pressures float up & down between epap MIn & Ipap Max. BUT if the user accidentaly sets Ipap Max lower that the number epapMin + PS equals, then PS gets forced down - restated epapMIn set to 8, PS set to 4 gives ipap of 12 but if the user sets IpapMax to 11 then PS gets dropped by (12-11) 1 CMs to 3 CMs. As stated, Ipap Max takes priority over PS & will alter PS if it has to.

DSM

Slinky wrote:there is no Max and Min IPAP (or EPAP for that matter) there is ONLY IPAP and EPAP.

If you are in VAuto mode, but are being asked by the lcd screen of the machine to enter IPAP and EPAP, your machine is malfunctioning. S mode asks for IPAP and EPAP. VAuto mode asks for Min EPAP and Max IPAP. The following are quotes from the clinical manual (which a very special person gave me):

"In S mode, you may set two treatment pressures—one for inspiration (IPAP) and one for expiration (EPAP)."

"(S mode) In S mode, you can set values for IPAP and EPAP."

"In VAuto mode . . . you may set the difference between the inspiratory and expiratory pressures using the Pressure Support (PS) setting (see “Pressure Support” on page 10). AutoSet pressure is a conceptual value. The patient is delivered an auto-titrated inspiratory and expiratory pressure based on the AutoSet algorithm, which has the AutoSet pressure as its midpoint. The AutoSet pressure is reported in data management and efficacy results information. You may also restrict the range of pressures in which the AutoSet algorithm operates, using the Min EPAP and Max IPAP settings respectively."

"Min EPAP and Max IPAP

"(VAuto mode) These settings allow you to restrict the range of pressures in which the AutoSet algorithm can operate, using the Min EPAP and Max IPAP settings"

Slinky wrote:Just got a call from the office of my old/new (original) sleep doctor I just switched to (he'd moved an hour away and I stupidly didn't follow him until now). He's upped my IPAP to 13.

In my not-so-humble opinion, following through on that change would require that you, or whoever, be sure exactly which mode you are in and that your machine is functioning properly in that mode. Again, if your machine is in VAuto mode and it is asking for IPAP and EPAP instead of Max IPAP and Min EPAP, my opinion is that your machine is not acting properly, based on my experience with my VPAP Auto and the words in the manual, above.

Also, if the doc is a pulmo, I might ask straight out if it matters to him/her how high your EPAP goes and if it matters how much distance there is between IPAP and EPAP. That is important information, IMO, for whoever sets the machine up, if you are going to run the machine in VAuto mode.

Slinky

I like jnk am thinking your machine is malfunctioning (why I asked if you were confident it was in VAuto mode). And knowing what your machine went through I wouldn't be surprised if it is.


DSM

These pics may make it easier to point out what is being said.

VPAP S MODE
===========
(set epap & set ipap)




VPAP VAuto Mode
===============
(set epapMin & set ps & set iapaMax)

The wiggly line is the epap-ipap cycling - the limits of the wiggly line are epapMin & IpapMax (the boundaries)