SleepyHead BIPAP questions.

[jedimark]

Hi. I'm hacking my way through improving SleepyHead's BIPAP support.. I have ironed out a lot of nasty bugs in the process.

I have a few of questions for BiPAP users:

On System One BIPAP machines.. When running in BIPAP mode, do they also have C-Flex/C-Flex+/A-Flex modes, or just Bi-Flex?

What you don't see in BiPAP mode is the Time@Pressure candlestick graph. I have just added support for two similar graphs sourced from IAP/EAP data. Is it necessary/good to have both IAP/EAP shown this way? (I have no idea)

Also regarding BIPAP IAP/EAP (lo/hi pressures) <-- What's the preferred generic terminology for them? (Preferably something both ResMed & PRS1 users will get)

[cflame1]

On System One BIPAP machines.. When running in BIPAP mode, do they also have C-Flex/C-Flex+/A-Flex modes, or just Bi-Flex?

BiPAP just has BiFlex

Also regarding BIPAP IAP/EAP (lo/hi pressures) <-- What's the preferred generic terminology for them? (Preferably something both ResMed & PRS1 users will get)

IPAP/EPAP

[jedimark]

Can BiFlex be turned off in the setup?

Here's what the BIPAP daily tab looks like in currently.


Is anything missing from this screen that a bipap user finds really important?

[builta]

Can BiFlex be turned off in the setup?

yes

[cflame1]

Is anything missing from this screen that a bipap user finds really important?

you probably should add a PS (pressure support) value... it's a set number so would go on the list on the left.

[jedimark]

PS? Pressure Support? I have no idea what that is..

Does it show in Encore? A screenshot would be awesome..

[cflame1]

see if you can get a file from Slinky's PR S1... I don't have a machine that new. PS is specific to an Auto Bipap (but doesn't show up the way that Robysue run's her's).

[builta]

PS? Pressure Support? I have no idea what that is..

Does it show in Encore? A screenshot would be awesome..

PS shows up in the pressure graph and is visible in the single graph that shows both IPAP and EPAP. It does not show up directly but is visible a because it can force either EPAP or IPAP to move to stay within a predetermined pressure differential of each other.

PS or "Pressure Support" identifies the difference in pressure between the IPAP and the EPAP.

For PRS1 BiPAP Auto (750 model), PS is a variable and has both a both a minimum and a maximum value (if the unit is set to run in BiPAP Auto Mode). The minimum value is fixed as the minimum two (2) CM H2O. The Maximum value is set in the Provider's Setup Menu. The machine will change IPAP or EPAP independently of one another to respond to events as long as the relative difference between IPAP and EPAP pressure is maintained within the set range of PS minimum and PS maximum. The result is that pressures move independently or one another but are constrained to relative range.

A person looking at the data is interested in this PS movement.

Non-Auto PRS1 BiPAPs (650 model or if the 750 is set to run in BiPAP Mode) do not use a variable pressure support. This is because the pressure support if fixed for those units. It is the fixed value of the difference between IPAP and EPAP.

I've got to look but, I will supply a link to JNK's dancer and stage explanation.

Cheers

[jedimark]

Thankyou both.. I'll try and absorb that info. I have a feeling that info is one of the pair of pressure values in the .001 summary file. I need to double check.

I've been looking at some screenshots of reports and stuff scattered around this forum, and they've got Breaths per minute, tidal volumes, etc... I'm not sure whether this stuff is calculated by the machine and stored or the software calculates it from the flow waveform. I'm also not really sure how useful that info is to people.

It's worth exploring I guess.

It's not exceptionally hard calculating most of that.. But it will slow the importer loader down a fair bit. I can do that sort of stuff for any machine that's got access to flowrate data, not just Bipap.

[builta]

Hi,

First the PS setting is just for the BiPAPs and the BiPAP advanced models.

Second I will PM you a report set from Encore Pro for a BiPAP Auto.

Third, Here is the explination of how PS works on a Respironics BiPAP auto in layman terms (quoted from JNK)

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.

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).

[robysue]

Contributing a bit more verbal info about S1 BiPAPs that I know for certain AND what I've been told about Resmed VPAPs.

1) Standard terminology on both platforms for the two pressure levels is IPAP and EPAP.

2) On the PR S1, you have Bi-Flex as the only choice for exhalation relief when running in BiPAP or Auto BiPAP mode. You can turn it off. If you turn it off, then there is a setting called "Rise Time" that controls the speed at which the pressure goes from EPAP to IPAP each time you inhale. Near as I can tell Rise Time is (very grossly) equivalent to one of the Ti settings on the VPAPs, although which one I have no real idea. On my own machine, I've been using Rise Time = 3 for most of the time I've had the machine. But the machine has briefly had Bi-Flex turned ON (with Bi-Flex = 3) by the tech who set it up. I'm the one who turned it off because I didn't like it. However in all my Encore reports, it still shows up that Bi-Flex = 3 and I assume this is because that's the last setting Bi-Flex was set at.

3) PS (Pressure Support) is something that is only found on bi-levels when they are running in Auto mode: Loosely PS is the difference between IPAP and EPAP. But the way PS is implemented on the S1 and the VPAP is quite different:

• On the S1, the PS setting is the maximum allowable value for IPAP - EPAP. On my machine the whole time I've been running in Auto mode, PS has been set to Max IPAP - Min EPAP. Maybe that's why it's not showing up? And the minimum value the S1 will allow for IPAP - EPAP is 2. The upshot of this is that whenever 2 < IPAP - EPAP < PS, the IPAP and the EPAP are allowed to vary independently of each other. But when IPAP - EPAP = 2 or IPAP - EPAP = PS, there are some constraints on how the pressures are increased or decreased.
  • When IPAP - EPAP = PS:
    • if the IPAP needs to be increased, then both IPAP and EPAP will increase at the same rate
    • if the EPAP needs to be decreased, then both IPAP and EPAP will decrease at the same rate
  • When IPAP - EPAP = 2:
    • if the IPAP needs to be decreased, then both IPAP and EPAP will decrease at the same rate
    • if the EPAP needs to be increased, then both IPAP and EPAP will increase at the same rate.
  • And at the start of the night, EPAP = min EPAP and IPAP =min EPAP + 2.
• On the VPAP, the PS setting is the fixed value for IPAP - EPAP. Hence IPAP and EPAP are always increased together on the VPAP. (And that's why the ResScan reports for VPAP mahcines can show the pressure info with only one curve.) At the start of the night EPAP = min EPAP and IPAP = min EPAP + PS.

4) For S1 users, it's important to have separate curves for both IPAP and EPAP pressures because they do vary independently most of the night. (See above.) For VPAP users, that's less important since the IPAP and EPAP curves will be vertical translations of each other.

5) For the Time@pressure tables for the S1 BiPAP Auto users. You need separate tables for IPAP and EPAP because they vary indepedently. As to what other information to provide, I'd ask the question: What information are you providing in the Time@pressure tables for the S1 Auto users? In Encore, there are computed indices for each type of event that triggers increases in IPAP/EPAP respectively. And the CAI is just stuck in the EPAP data since the machine does NOT raise pressure when CAs are detected. Whether these index numbers are actually useful for the user, however, is not at all clear and they are very easily misinterpreted by users. Many of us routinely ignore the index numbers or only look at them very briefly. For myself, I only use them to determine what kind of events were most often responsible for increasing the pressure from that level to the next. (High index for event type A + short time at pressure) implies events of type A were what was driving the increase in pressure most of the time. Could I live without this data? Yes.

6) And I'll add this too. It's very nice that you've added the humidifier setting added to machine settings. It's bothered me that Encore only lists the last humidifier setting on the summary data page. And I'm someone who actually makes fairly frequent, but small changes in the humidifier setting based on the weather, so this information being at my finger tips in the daily data is quite nice. Thank you.

[GumbyCT]

In the fwiw dept. -
Encore defaults the "Start of Day" to noon. I find this confusing and not normal. In EP1 it was something that could be changed under the "Demographics" tab. In EP2 I can't find anyplace to change it. So I ask that if you can, make it a feature that can be changed under Preferences for the user.

Maybe some folks work shift work and prefer something completely different than I do.

Thank You

[robysue]

In looking at the posted data a bit closer, I've discovered a silly (and hopefully trivial to fix) error. On those bar graphs at the bottom IPAP and EPAP are backwards. EPAP is ALWAYS the smaller of the two pressure settings.

And a clarification for others who might be wondering such things: The bedtimes show up correctly on MY computer which is in a different time zone that jedimark's. That's why the bedtimes in the posted data look so odd.