Insufficient air in middle of night only

[doughpat]

Hi all -

I've got moderate OSA and have been pretty good about using my Resmed Airsense 10 Autoset.

However, lately I have noticed a bit of a disturbing trend: I wake up in the middle of the night with the mask off. I (or my wife) dutifully remind myself to put it back on, but for some strange reason it feels like I can't get enough air!

This is so strange to me because when I first put the mask on when I first go to bed, its fine. I have no struggles, none of that awful suffocating feeling. It only happens after hours of sleep.

I recently turned up the humidity by 1 as I was having some issues with a dry throat, but the problem was happening before that.

Not sure if these settings are relevant, but here they are:
Pressure Relief: On
Temp 81 F
Humidity 6
SmartStart: On
Mode: CPAP
Set pressure: 9.0 cm
Ramp time: off
EPR on
EPR type: full time
EPR level: 2

Your help is deeply appreciated. Please let me know if there is any more information I can provide to help.

[zoocrewphoto]

It would be really useful to download sleepyhead and post some graphs of a typical night.

Without data, we are really just guessing. But I do see that you have an apap but you are using a straight cpap pressure of 9. It is possible that you are having more events during the middle of the night, and the pressure of 9 isn't enough to prevent those events. That could easily leave you gasping for air. The best way to fix the problem is to look at the graphs as they will show the events that are happening. You will probably also want to use a range of pressures to see what the machine would like to do and if it helps. you could switch your machine to apap and set it for 9-20 and see what it does.

[Julie]

I see that you're in Oregon, where I believe the usual humidity might be relatively high, yet you have your machine's humidity up at 6... is it possible you're just getting way more than you need and it's causing you to wake up (and feel suffocated)? I do agree though that Apap mode would be preferable unless you know a good reason why you're just on Cpap.

[Sheriff Buford]

A straight cpap pressure of 9 should be enough air without feeling suffocated. Could it be possible that you are taking the mask off, experiencing a event... waking the wife up and she is asking you to put the mask on? Regardless, to get proper therapy, you need to keep the mask on. Tape the mask on your face with some medical tape so when you take the mask off, it will immediately wake you up. It won't take long to train yourself to leave the mask on all night.

Sheriff

[Pugsy]

People tend to assume that the entire northwest is humid with lots of rainfall but it's not necessarily the case.
It depends on which side of the mountain range a person lives.
The west side along the coast...yes, fairly high humidity but on the east side of the mountain range it can be quite a bit different.
The Cascades block a lot of that wet weather from making it to the east side of the states in Oregon and Washington.
It's a lot drier on the east side of the mountains.

Besides....if it is very humid these newer machines won't necessarily add moisture on top of whatever the relatively humidity is...they simply won't use as much water because the air is already fairly humid.

Example....if someone is using the setting of 6...and if that setting means the machine wants to deliver 90% humidity...and the relative humidity is already 88% then the machine won't really add much moisture and very little water will be added to the air.
If the relative humidity is 95% and it's raining outside then the machine won't use any water at all because the air is already humid.

All this is of course assuming that the humidity inside the house is the same as outside which of course it most likely isn't especially in the winter months when we tend to heat our houses by some means.
Furnaces will dry the air out some...and wood heat especially so.

So which side of the mountains and type of heat will impact the humidity in the house....and if a newer machine like S9 or newer or System One or newer where the machines have humidity sensors that can tell what a person is actually experiencing in the house to start with...the machine may or may not be even adding much moisture anyway. They won't add moisture if the air is already fairly humid because it isn't needed.
Now the older machines without sensors for humidity...different story.

[doughpat]

Hi all - good ideas regarding the sleepyhead data. I'll work on getting that. Its been a while since I've bothered looking but I should! I

Regarding CPAP vs. APAP -- I'm not sure "why" I'm on continuous - I just haven't fiddled with it since getting the unit much. But now that I think about it, I actually bought this unit (cash) so that my older unit could be a "travel" setup. I will cross reference the settings on my older S9 and see if there are any differences. That'll be enlightening.

And finally, yes, I am on the beautiful (and far far less populated) east side of the cascades, where we get 10" of rain a year and tumbleweeds, junipers and a very dry climate dominate. It is also true that the humidity controls on these new machines are indeed dynamic and will only 'make up' for additional humidity instead of just "dumbly" adding more water. The effects of this can be seen by examining how much water remains in your reservoir fluctuating dramatically, depending on the ambient humidity.

[D.H.]

I agree that you should use Sleepyhead to see how you're doing. Also, since you have an APAP, you might want to leave the min on 9, but turn up the max; at least to 15. It shouldn't go there unless it needs to.

BTW, as far as I know, you can't use Sleepyhead on a phone, you need a desktop or laptop.