ozij wrote:pressures I can tolerate only thanks to EPR

ResMed CPAPs do make straight pressure very curvy, almost to the point of being cleverly disguised bilevels, since a pressure of 10 with EPR of 3 is really only giving 7 cm on exhale, right?

Right. Except when you have events -- then the EPR takes a break, and the exhale pressure goes up. That's a safety measure, (or maybe a CYA one...). The person on 10 was not - in principle - prescribed 7, so if they have an event (apnea, and snore), the exhale pressure will go back up.

O.

ozij wrote:Right. Except when you have events -- then the EPR takes a break, and the exhale pressure goes up. That's a safety measure, (or maybe a CYA one...). The person on 10 was not - in principle - prescribed 7, so if they have an event (apnea, and snore), the exhale pressure will go back up.

O.

Now, I'm a little slow but this sounds to me like straight CPAP with EPR is an alternative to the auto mode (APAP), as you kind of get an effective increase in pressure when it is responding to an event. Question for those in the know, could you compare an APAP with a 7-10 setting vs a CPAP with a 10 setting and 3 EPR? My guess is that APAP would try to adjust before the event, while CPAP with EPR adjusts after the event. (Probably C-Man is on the mark when he observes how I am trying to overanalyze everything.)

GaryG wrote:

ozij wrote:Right. Except when you have events -- then the EPR takes a break, and the exhale pressure goes up. That's a safety measure, (or maybe a CYA one...). The person on 10 was not - in principle - prescribed 7, so if they have an event (apnea, and snore), the exhale pressure will go back up.

O.

Now, I'm a little slow but this sounds to me like straight CPAP with EPR is an alternative to the auto mode (APAP), as you kind of get an effective increase in pressure when it is responding to an event. Question for those in the know, could you compare an APAP with a 7-10 setting vs a CPAP with a 10 setting and 3 EPR? My guess is that APAP would try to adjust before the event, while CPAP with EPR adjusts after the event. (Probably C-Man is on the mark when he observes how I am trying to overanalyze everything.)

Good question. (Although, I don't think you're slow, I don't think I've ever seen the C-Man off the mark, and he's a master analyzer himself. ) I admit that the little "suspending EPR" trick seems like a cool feature that actually makes the Elite II a more attractive machine to me in some ways than my VPAP Auto bilevel, since my machine can't raise EPAP without also raising IPAP. Although, I wonder if that suspension of EPR ever causes arousals on top of the event arousals or worsens the event arousals?

GaryG wrote:

ozij wrote:Right. Except when you have events -- then the EPR takes a break, and the exhale pressure goes up. That's a safety measure, (or maybe a CYA one...). The person on 10 was not - in principle - prescribed 7, so if they have an event (apnea, and snore), the exhale pressure will go back up.

O.

Now, I'm a little slow but this sounds to me like straight CPAP with EPR is an alternative to the auto mode (APAP), as you kind of get an effective increase in pressure when it is responding to an event. Question for those in the know, could you compare an APAP with a 7-10 setting vs a CPAP with a 10 setting and 3 EPR? My guess is that APAP would try to adjust before the event, while CPAP with EPR adjusts after the event. (Probably C-Man is on the mark when he observes how I am trying to overanalyze everything.)

Fixed CPAP with EPR is not an alternative to the auto mode for those who need varying inhale pressures. If your fixed pressure is 9, and you actually need 10 to keep your airway open, you can have 50 apneas and hour, and that fixed inhale pressure won't change.

A ResMed machine at a fixed pressure of 10 will give you a constant, never varying never changing pressure of 10 each and every time you inhale. It won't change that pressure, not matter how many or how few events you have. EPR lets you decide which pressure you will receive on exhale. It's a comfort feature, and the machine will override that comfort feature if you have events. The chart will show you an utterly stable pressure of 10 in red, and a (possibly) varying one in blue.

A machine on auto mode will vary its therapy pressure, depending on the events it encounters. When set at 7 to 10 it will give you a inhale pressure of 7 as long as you have not events that are indicators for a pressure raise. Your inhale = therapy pressure (red) will vary up and down depending on the events identified. If you need a pressure of 7 to keep your airway open when you inhale, that's the pressure you will have, regardless of either the EPR setting or the maximum pressure. If you need more, you'll have more.

True bi-level mode can be set to supply different pressures for inhale and exhale, for each and every breath, all night through. The inhale / exhale delta (difference) is firmly locked on the ResMed bi-level machines, and will not vary, no matter how many events you happen to have.

O.

Gary, I've been following this thread with interest, and enjoying learning. Thanks for sharing.

GaryG wrote:(Probably C-Man is on the mark when he observes how I am trying to overanalyze everything.)

Gary, do whatever gets you through the day....or night.

I'm just a pup.
O is much better at explaining this stuff......
as is obvious.

At this point, I can only share my experiences and
the reasons for creating said experiences.

carbonman wrote:

GaryG wrote:(Probably C-Man is on the mark when he observes how I am trying to overanalyze everything.)

Gary, do whatever gets you through the day....or night.

I'm just a pup.
O is much better at explaining this stuff......
as is obvious.

At this point, I can only share my experiences and
the reasons for creating said experiences.

Your message is getting thru loud and clear and I appreciate it. In fact, I glanced at my numbers and they were not so good last night, but I woke up refreshed with my nose clear (no sniffling). And so I'm trying to get myself not to download my numbers for a few days and then look backwards at the data. I think the danger is to have the numbers make me feel a certain way and I'm trying to stay clear of that.

Well, I've been "self-titrating" for the past 6 days, one more night to go before my appt with my sleep doc.

Here's a summary of my past 6 nights, followed by the last two nights of detail, followed by a chart of daily stats since the beginning of October. Would appreciate any feedback, along with questions to ask my doc. Seems like my numbers are good irrespective of my pressure settings, almost like my body adjusts to whatever I set the pressure to. As to how I feel? Well, I feel better now than I did pre-CPAP, but I haven't experienced nirvana yet, and so I thought I was on the path to get the sweet spot. But maybe I don't have a sweet spot, and I'm just chasing my tail.

As far as masks, I am currently alternating between the Fit Life FF mask, which irritates my chin, and leaves my teeth sore, and the F&P FlexiFit HC432 FF mask, which irritates the nose bridge.

bump

All that being said, I must bring up Schrödinger's cat - the act of observation affects the outcome.

Gary, did you have a lot of spontaneous arousals? Or a deranged sleep architecture? Either one might still be contributing to not having that $1,000,000 night, er day...er sleep?

provider wrote:All that being said, I must bring up Schrödinger's cat - the act of observation affects the outcome.

Which made me go a'Googling:
http://www.mtnmath.com/cat.html

And with that all that being said, I must bring up....

Well Gary, how did your appt with your Dr go? And how do you feel? I'm in no way qualified to really comment on your reports but it looks to me that you'd do pretty well in a narrow range of let's say 8-12cms or possibly straight cpap at 10 or 11cms. Of course it all depends on how you feel and how comfortable your mask is. Just a thought from my own observations, but I find that I'm "calmer" when I look at Mike's reports in cpap mode rather than trying to pinpoint every detail of the auto graphs and wanting to find something to improve on. For me, less is more. Keep us posted, Dori

Well, after consulting with doc, he frankly doesn't put much to "small" differences in AI results. He thinks whether a 0.5,1,2,3, etc, its all really the same, and only large factors, like if I was at 20 or 100 or more would be significant.

Based on my results, it looks like I can tolerate higher pressures than I need. My results are similar in 11-15 or 4-15 ranges. As a result of my consulation, I changed my settings in the 6-12 range. I'm feeling ok, not great, not terrible. But I have to say, after having a bad night on Thursday, I feel a lot better today after a good night of 8.5 hours of sleep with AI showing 0.7 on my read-out.

So I'm defintely getting benefit from CPAP. Just not nirvana (yet).

My doc thinks my efforts to find an optimal sweet spot are futile, as he thinks I'm doing fine now.