ResMed Pressure Support

[IFLEW]

I have been on CPAP or APAP for nearly a year. I started with Respironics and now have a Resmed VPAP Auto 25 as listed in my equipment below. I have read, downloaded, and printed everything I can find about the Resmed A10 algorithm. I understand (I think) the discussion about whether it responds to Apneas above 10cm pressure. I also have the Rescan software and card reader so I can keep close track on my performance. My last visit to my doctor I took several print outs and he was very receptive of my efforts to understand the therapy.

My question is how the Pressure Support setting works into the equation. With my current settings of max IPAP 18, EPAP 7.4, and pressure supplement 4.0 the machine goes straight to 11.4 IPAP pressure and never is less. The IPAP works its way up to a maximum in the 15 range and then back down depending on the Hypopnea events. Does the Pressure Support establish what the EPAP will be when the IPAP is at 15? Is the EPAP always 4.0 (at this setting) less than the IPAP? My doctor would prefer a print out of what the EPAP is, rather than IPAP. I cannot find that option in the software.

I was titrated to about 12 cm pressure with a Respironics Auto BiPap machine. I found both the light and noise annoying and was able to change to ResMed which I like very well. I am in the area of 1 AI and 5 AHI most nights. I feel more rested using this machine but am still looking for the "sweet spot" and trying to understand the ResMed Algorithm.

I have experimented some with raising the EPAP but that seems to lead to bloating and other bodily functions. I hope some of my question and frustration makes some sense.

Sorry about the original confusion... I was talking pressure support and have cleaned up the post.

Sleep well...

[Slinky]

Supplemental pressure??? Do you actually mean the Pressure Support setting? I have the Auto 25's predecessor, the VPAP Auto so maybe there is some supplemental pressure that is available on the Auto 25 but not the Auto?

If it IS the Pressure Support you are talking about jnk gave an EXCELLENT explanation of how it works differently than the Respironics' Pressure Support. (Much as I hate to say it, Respironics' PS is so easy for me to understand - and Resmed's is corn-fusing! - I have to read jnk's explanation every time we do a pressure setting change as I can't seem to keep the understanding in my beady brain).

"I think you may misunderstand the differences between the two machines and how each machine must be set. They are both good autobilevels, but you can't set either of them up correctly by attempting to use the numbers that were used on the other brand of machine. You have to think about the numbers and translate them for how you want the other brand of machine to run.

As an illustration, think of inhale and exhale as being two dancers. On the Respironics dance floor in the Respironics world, the two dancers dance two different dances without caring what the other dancer is doing. You simply set the size of the dance floor and you tell the dancers the maximum distance they are allowed to get from each other during their separate dances (there is an automatic minimum to keep them from bumping into each other), and they each do their own thing. Sometimes they dance close to each other, and sometimes they dance far apart. That distance varies. On the other hand, on a ResMed dance floor in the ResMed world, the two dancers do the same dance and are always the exact same distance from each other, but they can still roam the full dance floor, as long as they do it together. So if you mistakenly set the fixed distance of the dancers to be the same size as the dance floor, you keep the dancers from moving at all.

In other words, for the Respironics machine, you set the maximum IPAP and minimum EPAP (the size of the dance floor), then you set the MAXIMUM pressure support, or maximum distance allowed between the two separate pressures (dancers). For the ResMed, you similarly set a maximum and minimum (the dance floor), but then you set the ACTUAL pressure support, the fixed distance (or, difference) between inhale pressure and exhale pressure for the night. On that machine, those two pressures increase and decrease TOGETHER, NOT SEPARATELY, moment to moment, during the night (since the two do the same dance together).

It seems that the person who set up your machine didn't understand that difference between the two machines and set up the ResMed as if it were a Respironics. That is incorrect. If you want the ResMed to run as an auto, make sure the pressure support number is a number LESS THAN the distance between Max IPAP and Min EPAP so the dancers have some room to move. If the machine isn't set up correctly, it is the person who set it up who has kept the machine from running as an auto. That is not a limitation of the machine; it is a limitation of the person who set it up. That person was confused. So don't blame ResMed.

As for which approach to autobilevel dancing is best, I don't know. I just know the two approaches are different and that before you set up one brand after using another brand, you had better learn something about dance floors and choreography in the other world and translate from one to the other, if you want to see a dance.
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there is nothing wrong with keeping the dancers pinned, if that's what a person wants to do. Some like the feel of a ResMed autobilevel in auto mode (because of how Easy-Breathe feels) but don't want the pressures to move around at night. So to get straight bilevel while the machine is in VAuto mode, they purposely make the pressures stay the same by setting pressure support the exact distance between Min EPAP and Max IPAP. But if a person wants to use a ResMed autobilevel as an autobilevel, the stick has to be shorter than the walls or the pressures won't vary."

[IFLEW]

Yes, my apologies to you and the others who read and did not offer an answer. It is pressure support I am talking about and that article explains perfectly how ResMed works. I thank you for your reply. As I said I tried to search for all the articles about how the ResMed worked before posting my (incorrect) question... but I never found this one.

Thank you again. Now I am closer to understanding what the charts mean.

Ed

[Slinky]

No need to apologize. We are so fortunate here to have people like jnk, RestedGal, Velbor, dsm ..... and so many others to help us understand our therapy.

[rested gal]

I'm so glad you posted Jeff's (jnk)'s excellent explanation of Pressure Support in those two major brands, Slinky. It's a classic!

Jeff's great explanation, which Slinky quoted, about the difference in how the ResMed VPAP Auto (and "25") and the Respironics BiPAP Auto handle the "PS" (Pressure Support) setting can be found here:

viewtopic.php?p=376749#p376749
topic: ResMed VPAP Auto 25 Clinician's manual

[jnk]

Hey, it was just a repackaging of what you folks had taught me here.

As for the question and statements:

Is the EPAP always 4.0 (at this setting) less than the IPAP? My doctor would prefer a print out of what the EPAP is, rather than IPAP. I cannot find that option in the software.

I believe the software only shows the IPAP in the software printout for the Auto 25. (That is an improvement over what the software shows me for my machine, though--it puts a line directly in the middle of IPAP and EPAP!) Since pressure support is constant with the ResMed brand, you are correct that EPAP will always be exactly 4 cm below IPAP at any given moment if pressure support is set at 4. So the doc can look at that one line for IPAP and immediately know the exact IPAP AND EPAP at any given moment.

My experience may be very different from yours, but these days I keep minimum EPAP around 8 most of the time, but have to crank it up to 10 when my nose is stopped up from allergies or irritation or stress. Any higher than that, and I get some aerophagia. I usually know within a few minutes of masking up whether it is going to be an 8 cm minimum EPAP night or a 10 cm minimum EPAP night.

jeff

[Slinky]

jnk, that's been a confusing point for me. The Resmed VPAP Auto, just 6 months "older" than the VPAP Auto 25, reports the mid-pressure between IPAP and EPAP, instead of the IPAP pressure as the VPAP Auto 25 does. I'm hesitant to post a reply to a lot of Auto 25 questions 'cause on accountta I'm never sure if there is a difference on the point of the question between the Auto and the Auto 25. And then my having had the S8 ResLink and oximeter on my VPAP Auto for so long I've forgotten what data the Auto (and before that the S8 Elite and S8 AutoSet Vantage) provides via ResScan 3.7 w/o the S8 ResLink and oximeter so again I hesitate to answer questions along that line.

[jnk]

jnk, that's been a confusing point for me. The Resmed VPAP Auto, just 6 months "older" than the VPAP Auto 25, reports the mid-pressure between IPAP and EPAP, instead of the IPAP pressure as the VPAP Auto 25 does. I'm hesitant to post a reply to a lot of Auto 25 questions 'cause on accountta I'm never sure if there is a difference on the point of the question between the Auto and the Auto 25. And then my having had the S8 ResLink and oximeter on my VPAP Auto for so long I've forgotten what data the Auto (and before that the S8 Elite and S8 AutoSet Vantage) provides via ResScan 3.7 w/o the S8 ResLink and oximeter so again I hesitate to answer questions along that line.

You are a wise woman, Slinky. I learned that the hard way by giving the wrong answer on this particular question a few times.

The clinical manual for the Auto 25 says: "The average IPAP pressure is calculated and recorded each minute in all modes."

The clinical manual for the VPAP Auto says: "The average pressure is calculated and recorded each minute (VAuto mode: average AutoSet pressure; S mode: average IPAP pressure). The pressure reported in the Efficacy Data submenu for a single session is the 95th centile pressure for mask-on time (VAuto mode: 95th centile AutoSet pressure; S mode: 95th centile IPAP pressure)."

So with the VPAP Auto, it depends on what mode you are in. The Auto 25 does it the same in all modes. IF I understand the above correctly, that is.

jeff

[Slinky]

Go ahead, jnk, confuse me some more! No, really, I understand what you are saying now. Its Resmed who is corn-fusing me! I think I'd rather have the extra graph lines for IPAP and EPAP.

I can understand why they don't bother since the PS keeps them in sync w/each other, never varying. But it would be easier for this tired ole brain to absorb. I think. Maybe.

[jnk]

Go ahead, jnk, confuse me some more! No, really, I understand what you are saying now. Its Resmed who is corn-fusing me! I think I'd rather have the extra graph lines for IPAP and EPAP.

I can understand why they don't bother since the PS keeps them in sync w/each other, never varying. But it would be easier for this tired ole brain to absorb. I think. Maybe.

I hear ya. Sometimes I think I might like to get the ResLink just to see those lines!

[Slinky]

PM me w/your e-mail addy if you want to see some. I'll send you a copy of mine.

[IFLEW]

Slinky, JNK, Rested Gal... Thanks so much for your reply and all the cross talk between you. It cleared up a lot of things. I set the pressure support to 3 instead of 4 to give me a higher EPAP. One night does not a test make but if last night is an indication I am going in the right direction. I try not to get too carried away with numbers and concentrate on how I feel but having the card reader and software makes it easy to get hooked on the figures.

I do not think I will pursue it but from you discussion I infer that Reslink gives a lot more information than the data card. Is that correct?

Also, is the Clinical Manual for the Auto 25 available in a PDF (or other) form?

Thanks again, I am active in several forums in other areas but am just getting my feet wet in the structure of this one.

Ed

[falvesjr]

Ed,

Check your PMs...

-F

[Slinky]

Well, it looks like falvesjr will take care of the Clinicians Manual.

As for the S8 ResLink, its just as well you're not interested at this point as Resmed has discontinued manufacturing the ResLink. I don't know what they are doing, if anything, about overnight oximetry w/their xPAPs now w/o the ResLink. I know they are going w/ResTraxx but I have no experience w/ResTraxx nor do I have any idea at this point just what they are up to regarding "accessories" for data.

[jnk]

One raises delivered EPAP by raising EPAP Min. Changing PS just changes the distance between IPAP and EPAP, so decreasing PS and leaving EPAP Min where it is mostly just lowers your delivered IPAP.