Clarification ... Apnea Suppression Pressure

[janp]

I guess I'm on "information Overload" from everything I've been reading and trying to digest.

I'd appreciate a consensus on the question ...

In Auto mode, does a higher minimum pressure typically do a better job of suppressing apneas better than a higher maximum pressure setting?

Thank you,

Jan

[Hawthorne]

In trying to get better data and therefore, better sleep with an auto, yes, raising the minimum pressure is much more effective in dealing with events than raising the maximum pressure.

Raising the minimum slowly and only making changes every 4 days to a week is much better.

Some people set a narrow auto range ( mine is 2 1/2 cm between the minimum and the maximum pressure and I get a 90% pressure 1cm below the maximum consistently).

The minimum is usually better if it is just a cm or so below or right at, your titrated pressure. The maximum generally doesn't matter unless you get run away Centrals with too high a maximum. That, in most cases, is unlikely though.


The other thing that can happen with to wide a spread, is that the changing pressures can cause arousals and sleep disturbance. Work on the minimum though!

[Wulfman]

Welcome to "information overload", Jan.

"Yes". When using an APAP/Auto, it's important to have your minimum pressure set to where it will prevent the vast majority of events. If your minimum pressure is too low, it can take too long for the pressure to get to where it needs to be.....if it can get there at all. So, by having the minimum pressure at the optimum point, it will get most of them. Some of us differ on where to set the maximum pressure, but it depends on the person and their type of "events" and whether they still snore and have leaks above the minimum pressure that may cause runaway pressure increases. I'm one who believes in a narrower range of pressures to prevent/restrict those runaways.


Den

[rested gal]

I agree with Hawthorne and Wulfman about the importance of the minimum pressure setting with an autopap for preventing apneas:

Results: 1st night with Auto A-Flex (topic started by TSSleepy)
Two nights graphs posted using pressure range 4 - 20 and 10 - 20
viewtopic.php?p=348963#p348963

November 2008 Just got an APAP (topic started by turbosnore)
viewtopic.php?p=319619#p319619

October 2008 Turning off Aflex and Cflex (topic started by DoriC)
viewtopic.php?p=307265#p307265

September 2008 New Guy - Need Help w/Settings (topic started by alanhj13)
viewtopic.php?p=294319#p294319

Wulfman, DreamStalker, and ozij explain why autopaps make changes slowly.
December 2008 Why adjust APAP. Isn't it auto? (topic started by oxygenium65)
viewtopic.php?p=323218#p323218

_____________________________________

I also think the minimum EPAP pressure is the most important one to set "right" when using an autotitrating bilevel machine:

My thoughts about EPAP setting on a bilevel machine (and min EPAP on the BiPAP Auto.)

November 2007 - EPAP is for more than just comfort exhaling.
viewtopic.php?p=227068#p227068

December 2007 - my understanding of how a bipap titration is done.
viewtopic.php?p=231786#p231786

May 2008 - discussion with RonS about importance of EPAP setting.
viewtopic.php?p=265020#p265020

[mdbarthe]

I can speak from firsthand experience on this topic. My APAP pressure range was initally set by my RT at 10-20cm. I was titrated at 13 originally, then a year later lowered to 12cm.

For the first few months I had my APAP (after having switched from straight CPAP after 2 years) I had AIs around 5-9 per night (AHI of between 10-15 per night).

About 1 month ago, I raised my pressure range minimum from 10 cm to 13 cm. My AIs dropped to 0.1 to 2.0 per night and my AHIs reduced to between 5-7 per night. Those figures have stayed consistent since I upped my minimum pressure in the range.

I should mention that I have always had an extremely low leak rate (many nights a complete flat line) and all other variable remained constant. For this reason, I am convinced raising my minimum pressure in the range was the key to better therapy.

[janp]

Thank you all for taking the time to respond.

It would appear that raising the lower limit can help to reduce apnea events!

Looks like that's where I'm headed.

Thanks again.

Jan

Rested gal ... you continue to amaze me with your source of reference information!!!