Help with S9 runaway pressure
Newbie here, love the forum thanks to all.
Briefly, I was on a cpap about 12 years ago for 18 months than had throat surgery which cured the problem. So I am familiar with the trials of getting used to cpap.
Last fall I was feeling tired all the time, and mentioned to my doctor that the symptoms felt a lot like sleep apnea. He did an at home sleep study which showed I had apnea. As my insurance doesn't cover anything I am basically on my own with no support.
But I have this great community, here, thank you. I'm still working on dialing in my pressures but am frustrated with the pressure if I wake up during the night. I don't know why but I have been waking up 1-2 hours before my normal wake up time. As soon as a wake up the pressure goes to the max. I often get up and pee then try to settle back to sleep. Within a couple of minutes the pressure will go from 7.6 to the maximum 12.0 which then makes it hard for me to get back to sleep. My typical (?) pressure is around 9.
I'm assuming that when I am awake the algorithm is confused and jacks up the pressure because of how I'm breathing. Is this correct? Any suggestions for how to breath or what to do so this doesn't happen??
I don't use the ramp feature, I have the epr set at 3 which seems comfortable to me.
Thanks for the help.
RE: Help with S9 runaway pressure
What's your ramp and ramp time setting?
Personally I don't use the ramp but it would seem if you need a little time to get settled down and back to sleep, and don't find the lack of air on a lower setting discomforting then setting the ramp to give you this leeway might work for you.
I am a newbie and can't be counted on to know anything, so take my comment as unverified rumor until proven otherwise.
In any case you might want to post these settings since others will surely ask about them and you might get faster help.
Sweet Dreams,
HerbM
Sleep study AHI: 49 RDI: 60 -- APAP 10-11 w/AHI: 1.5 avg for 7-days (up due likely to hip replacement recovery)
"We can all breathe together or we will all suffocate alone."
RE: Help with S9 runaway pressure
I don't use the ramp. However, what is weird is as soon as I wake up the pressure goes up (even if I haven't taken off the mask or stopped the machine). I guess I could use the ramp and put in on 30 minutes or so and if I wake reach over turn the machine off, then back on so that it is ramp mode. I was just wondering if anyone else has had this problem and if they had any suggestions.
RE: Help with S9 runaway pressure
(02-10-2014, 02:48 PM)tahoemark Wrote: I don't use the ramp. However, what is weird is as soon as I wake up the pressure goes up (even if I haven't taken off the mask or stopped the machine). I guess I could use the ramp and put in on 30 minutes or so and if I wake reach over turn the machine off, then back on so that it is ramp mode. I was just wondering if anyone else has had this problem and if they had any suggestions.
I have your same machine and I have noticed that I breath heavier after I get up or wake up not sure if that's why the flow is heavier.
My setting at the moment is ramp 4 and total is 13. I hit stop when I get up so when I come back the autoset starts the ramp which helps me settle back in, but when I wake up just lying in bed my flow seems high even though my graph readings show I only got up to 12.9 one time and the machine dropped me back into the 8 range or lower during my sleep duration.
So maybe you could try the ramp, hit stop and this might help the higher air flow to slow down till you go back to sleep.
Good luck, the machines are teak here n there sometimes to fit each person, just make sure your not getting leakage, when my mask leaks the machine increases the air flow.
RE: Help with S9 runaway pressure
tahoemark,
It would be useful to see the data with the graphs zoomed in to show one of these periods where you are awake (and trying to get back to sleep) while the machine is increasing the pressure up to your max setting.
My guesses about what might be causing this behavior:
1) The machine has no way to tell when you are asleep and when you are awake. And normal wake breathing is often much more ragged than normal sleep breathing. And so the machine is misinterpreting normal wake breathing patterns as sleep disordered breathing and scoring "false events" and responding by increasing the pressure.
2) Much deeper than normal breathing right after you turn the machine back on, followed by a return to much shallower, but normal breathing as you are just beginning to drop off to sleep. The deeper than normal breathing sets up a rather large running baseline for airflow, and the (normal) drop in airflow once you start settling in, however, is great enough for the machine to mislead the machine to score a hypopnea or two (or even an OA or two), which leads to the pressure increase.
3) The machine is detecting what it thinks is snoring or flow limitations. Some people have a tendency to do some very soft (almost inaudible) snoring just as they're starting to fully relax into sleep. If this "snoring" has the proper kind of vibratory signature in the wave flow data, the machine will think it's real snoring and increase the pressure pretty rapidly. Flow limitations are scored based on some very subtle changes to the shape of the inspirations and it's possible that the raggedness of normal wake breathing may make some of the inspirations have a shape other than the round, parabolic shape of normal sleep breathing inhalations. And once the flow limitations are scored, the machine will increase pressure in an attempt to smooth out the inhalations.
Since you are comfortable with your min pressure setting of 8cm and the problem is that the increase up to 12cm is what's bothering you and making you wake up further rather than allowing you to settle back into sleep, you might find that using the ramp for a brief period would keep the machine from increasing the pressure until after you are soundly back to sleep. I'd suggest starting the ramp very close to your min pressure and the ramp time something pretty close to how long it usually takes you to get back to sleep after the bathroom breaks. In particular, I'd suggest a starting ramp pressure of 7 or 7.5 cm and a ramp time of 10 or 15 minutes.
RE: Help with S9 runaway pressure
I'm curious as to why you don't use the Smart on-off that the S9 machines provide; it sure beats having to turn the machine on and off manually. I have my ramp set to 5 minutes with a starting pressure of 8, with anything lower than that, I feel like I'm suffocating.
INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE.
ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA.
RE: Help with S9 runaway pressure
(02-10-2014, 02:48 PM)tahoemark Wrote: I was just wondering if anyone else has had this problem and if they had any suggestions. Most of the time when I wake up, the screen shows pressure around the minimum
Not all of us can sleep 8 hours solid and wake up feeling refreshed, ready to conquer the world.
I don,t sleep right through the night, for example ... just woken up 5 morning, made myself a cup of tea and I,m here on the board,
I,ll go back sleep for an extra hour or two, not sleep hygiene text book but I,m okay with that, also might take an afternoon nap if needed
It could be something unrelated to CPAP which need some detective work. Avoiding sleep on your mack might helps, any dry mouth or/and stuffy nose, OTC or prescription drugs
What your AH, leak and pressure ... median, 95th percentile, maximum
Check the software that you,re using, whats going prior waking up ... large leak, Pressure maxing up, apnea and duration, clusters of events, flow limitations. If variable pressure affecting your sleep, you might look into setting the machine in CPAP mode so it deliver a fixed pressure all night
RE: Help with S9 runaway pressure
Thanks for the input. It didn't occur to me that I could set the ramp start pressure just slightly under my minimum pressure. As it is a new machine the start pressure was set at 4.0 which I find is not enough but I will bump that up and see how that works. Robysue I did look at the breathing on sleepyhead and didn't see any events or exaggerated breathing. The events that did show up were well after the pressure was up to the max. Anyway I will try using the ramp and seeing if that works out. Of course my other problem is I start thinking about things I have to do when I wake up, so add that in with any discomfort from the cpap.... well there goes sleep.
I'm frustrated with the first 30 days but having been through this before I know it takes time to get comfortable with everything.
Thanks all for the thoughtful replies.
02-11-2014, 02:38 PM
(This post was last modified: 02-11-2014, 02:41 PM by zonk.)
RE: Help with S9 runaway pressure
(02-11-2014, 01:38 PM)tahoemark Wrote: The events that did show up were well after the pressure was up to the max. What type of events ... obstructive or central
The autoset increase pressure in response to flow limitation (up to the max if needed) which are early signs of obstructive apnea ... not central apnea. Even with the best optimized setting, the machine cannot prevent all apnea events all the times, every night
You did not say whats the leaks stats are
RE: Help with S9 runaway pressure
Tahoemark--That high end pressure business is something that I have experienced on my S9 autoset every once in awhile, but not too often. When it occurs, it's also when I put the mask back on and turn the machine on again (I don't use the ramp feature) after a visit to the bathroom. While I haven't tried to analyze why it happens as others have, I just turn the machine off again, wait about a minute, and turn it back on and all is well again.
In my case, the S9 Auto is running fairly wide open with a pressure range of 12 to 20.
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