Advice..Narrow APAP press range or CPAP?

[Engransan]

Advice..Narrow APAP press range or CPAP?
I have gradually increased my Apap minimum pressure to 13cm allowing my machine to more rapidly respond to apnias and hypopneas. I have noted that my pressure graph tends to remain at or near 14cm but occationally drifts down to 13cm sometimes resulting in a few (10-15) apneas. Would I be better off setting the machine to CPAP mode? What would I sacrifice?
Engransan

[twokatmew]

You would sacrifice the machine's ability to go higher than your set (CPAP) pressure as needed. But ... the machine wouldn't go so low as to allow those apnea clusters to appear ... theoretically anyway. The only way to know for sure is to try it.

I've read that rule of thumb is to set CPAP pressure at the APAP's 95% pressure average. But ... that 95% will vary depending on your lower APAP setting! Before switching to CPAP, you might want to try bumping up that lower APAP pressure and see how you do. At any rate, it might give you a better idea of what pressure to start with if/when you try CPAP mode.

The good news is that your machine is capable of both CPAP and APAP, so you can use whichever works best for you -- and change it as your needs change.

[Engransan]

Thanks TwoKat. I had read on this forum that my machine ceases to respond automatically to apnias/hypopneas when the minimum press is set above 10cm however my daily graphs do not indicate this. I am considering a slight increase closer to 14cm before trying CPAP.
Engransan

[twokatmew]

Thanks TwoKat. I had read on this forum that my machine ceases to respond automatically to apnias/hypopneas when the minimum press is set above 10cm however my daily graphs do not indicate this. I am considering a slight increase closer to 14cm before trying CPAP.
Engransan

It's incorrect that ResMed machines cease to respond to events above 10cm. ResMeds respond differently above 10cm! They are more conservative about responding to events above 10cm in that the machines adjust pressure upward when they detect snores and/or flow limitations. This is to prevent the machines from increasing pressure in response to what might be pressure-induced central apneas.

[mars]

The only way to know for sure is to try it.

The good news is that your machine is capable of both CPAP and APAP, so you can use whichever works best for you -- and change it as your needs change.

Hi Engransan

If you follow twokatmew's advice above, you will eventually find out what is best for you. As this is a lifetime therapy it is best to spend some time on working things out.

What I am working towards is

low AHi
but not at the expense of more centrals
no clusters of AHi
no leaks
few or no interruptions for bathroom visits or banana breaks
and feeling good in the morning.

There may be other criteria that I cannot think of at present.

I usually try a setting for about a week to ten days to see how it goes (providing it is not obviously extreme), then compare the average with other settings. After nearly 3 months of this I am about a month away from finally working through all reasonable settings (both apap and cpap). I have found that good AHi results can come from a variety of settings, so we all need to develop our own criteria for the best therapy, and work towards that.

cheers

Mars

[DoriC]

Mars, I think it would be interesting if you could explain your system for trying out different settings,is it straight pressures, auto settings,etc? What was your original titration pressure? We finally got to the best setting with lots of help but when I experimented on my own it sometimes got confusing.