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Do CPAP machines come with a reverse ramp feature? By this I mean that the pressure starts close to the max and slowly decreases unless necessary instead of the other way around.
The reason I'm asking is that most nights, unless my Airsense 11 Auto ramps up quickly enough, I usually wake up 10-15 minutes after falling asleep with a jolt and a deep inhale. On bad nights, this happens a few times before I can fall asleep. On good nights, the machine ramps up quickly enough for me to stay asleep. I've attached an OSCAR screenshot of a typical night for me where I don't wake up right after falling asleep.
Current machine: ResMed Airsense 11 Auto
Min pressure: 7
Max pressure: 15
EPR: Off
Ramp refers to a feature during which pressure is kept artificially low ( often below therapeutic values ) for a period of time.
I believe you are referring to the algorithmic response to events or the lack of events.
When an obstructive events occurs pressure is increased for a period of time. Should no events be detected pressure will be decreased. This is limited to stay within the maximum and minimum values defined in your settings. This is the simple description of the algorithms of all auto CPAPs.
Gideon - Project Manager Emeritus for OSCAR - Open Source CPAP Analysis Reporter
I'm not an expert so I can't say that's necessarily the right answer but it seems to me like if you're feeling like you don't have enough pressure... turn up the minimum?
It's possible to change the 'Ramp Start Pressure' - the default is 4, which I found to be woefully low. It's in the clinical menuu along with the other comfort features.
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Thank you all for your replies. I think I spoke incorrectly in my original post and ended up asking the wrong questions.
The problem I'm trying to solve is that sometimes when I'm falling asleep as I go from light sleep to a deeper stage of sleep, I wake myself up with a silent snore. I've attached a screenshot that shows what it looks like in OSCAR. You can tell when the event occurred by looking for the spike in flow rate close to the green bar. The minimum pressure here is 8.6 instead of my usual 7 because I tried bumping it up to see if that would help and it did but I also think that the aspirin I took before falling asleep was the main contributor.
My thinking in the original post was that to alleviate the issue, my CPAP allowed me to set an artificially high and temporary starting pressure to get me past the 15 minute mark when I most often wake myself up. The CPAP would then follow its normal algorithm and let the pressure drop back to my minimum since I usually spend most of the night close to my minimum pressure. For example, if my current low and high pressures are 7 and 15, I could artificially set the CPAP to start at a pressure of 11, ride out the first 15 minutes of sleep, and the CPAP would then automatically adjust the pressure lower following the normal algorithm since I don't need it that high for most of the night.
I'm not entirely sure what causes it other than it seems to get worse when I have a cold or some other throat inflammation (like I do now) and I also don't know if there's a term for this event. I can tell you that it kicks me back from sleeping to fully awake and it takes me another 15 minutes or so to fall back asleep where I either progress to real sleep or silent snore myself awake again for another try. It's like I get really sensitive to any airflow restrictions due to muscle relaxation.
That "event" is a sime basic arousal meaning your sleep transitioned to a less deep form of sleep.
Awake breathing is typically rather irregular but I see none of that in this segment. In other words I don't see evidence of you being fully awake at anytime during this segment.
Gideon - Project Manager Emeritus for OSCAR - Open Source CPAP Analysis Reporter
I had the idea of reverse ramp a while back too. I would get a 'pop' of quick collapse that would disturb my drifting off to sleep pattern. Without the feature though, it seems the only solution is to bump the min pressure up a bit. That seems to have worked for me.
I think it could be a useful feature, but likely would generate confusion and support calls from many users.
Preamble:
For the last few months I have simply been lowering my min start pressure (on the Vauto Min EPAP 4.4). Seems to be working fine for me, for about 2 months now that I no longer daily look at my data, maybe only 1x or 2x per month.
(Now for most this is too low, but the reason I do this is so that when I am asleep and my airways are not obstructed, this allows the machine to bring the pressures way back down again during the course of the night. Something to do (in my warped mind anyway) with having longer Time at Lower Pressures during the course of the night. This way many of my side effects of CPAP have been largely reduced.)
However on Dec 6th I tested RAT+ and had a somewhat difficult month. With blocked nose I found this low starting pressure was not enough to allow me to comfortably breathe while trying to fall asleep.
Here is what I did:
I left the machine settings as they were (in my case Min EPAP 4.4, Max IPAP 10.0 and PS 1.8), but to get the pressures up a bit, to allow me to fall asleep, I simply held my breath long enough to hear the machine FOT'ing, and repeated until I felt my breathing was fine. This resulted in the machine temporarily ramping up the pressures enough to allow me to fall asleep. Of course, the AHI numbers increased a bit, because of these artificially introduced OSA, but this is to be expected. AHI still < 2.0 most nights, anyway.
Now, YMMV and I am not suggesting this may help you, but this is my way of "manually" introducing something in the way of what are describing. Not sure if you would help you, or what the expert opinion of this would be, worth trying?