pressure support functions philips resperonics bipap

[keithy62]

Have just purchased a philips respironics bipap sv auto advanced recently and am waiting an appointment to see a sleep specialist which will take sometime but have been using it in the meantime as is much better than my old fisher and paykel cpap. Have set it up with pressures i seem to tolerate reasonably well but have a question regarding epap max or min pressures in relation to the pressure support max and min functions as to what these two functions actually do and how they relate to minimum and maximum epap pressures as raising one of the pressure support functions can seem to alter max or minim pressures. My first experience with a machine with pressure support so dont understand what it's function is

Current settings are: Max pressure 16.0 Min EPAP 6.00 -- Max EPAP 10.5 -- P Support Min 4.0 -- Pres Support Max 6.0 Model Number SN P09887473

[palerider]

have a question regarding epap max or min pressures in relation to the pressure support max and min functions as to what these two functions actually do and how they relate to minimum and maximum epap pressures as raising

So, what's your question?

If it's just "what is PS"? it's the difference in the EPAP (exhale) pressure and IPAP (inhale pressure).
Classically, in bilevel treatment, PS is used to enhance ventilation of patients who're having breathing problems.

For most people on CPAP, it *might* just make it easier for them to breathe with the machine.

Too much PS will increase your chances of over-ventilation and end up increasing your central apnea count (Philips calls them "open airway" apneas, for no apparent good reason.

PS doesn't have any relation to the amount the EPAP increases.

[keithy62]

Thank you for your reply Palerider. Still dont understand function of PS. Thought pressure difference in my case would be the difference Min IPAP min and EPAP max with that being 4.5. Sorry for dumb question,my question prior to seeing my sleep specialist is are my PS settings low enough or not excessively high to cause central apnea events. Once again Thanks for your reply.

[palerider]

Thank you for your reply Palerider. Still dont understand function of PS. Thought pressure difference in my case would be the difference Min IPAP min and EPAP max with that being 4.5. Sorry for dumb question,my question prior to seeing my sleep specialist is are my PS settings low enough or not excessively high to cause central apnea events. Once again Thanks for your reply.

You're getting your terms mixed up.

There's no "min ipap" and "epap max" on machines.

There is MinEPAP, and MaxIPAP, and PS on auto adjusting machines. The EPAP varies based on breathing events.

PS is the difference in exhale pressure and inhale pressure on every breath.

If your EPAP on a single breath is 8, and you have a PS of 3, then when you inhale, the pressure will go up to 11, then drop back to 8 when you exhale.

If you want to know more about PS, then watch these videos:

https://www.youtube.com/watch?v=A-SlO2dU8Og
https://www.youtube.com/watch?v=BdeOiDJmbrk

[keithy62]

Apologise for that min ipap max epap mistake.Only saw mistake after i had posted. Thanks for further information pressure support function.functions.

[Respirator99]

... are my PS settings low enough or not excessively high to cause central apnea events. Once again Thanks for your reply.

ASV machines are not like ordinary CPAP or APAPs. They need a high PSmax to enable them to treat central apneas if they occur. For example Resmed recommend PSmax be >=15. Here's an extract from the relevant section of the Resmed ASV manual - the Philips will be similar.

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