Is a Sudden Large Change in AHI Independent of Mask Type

[Comfortably Numb]

Last night was my third consecutive session with a full face mask (F20). Prior to that I had been using a nasal mask (N20). The quality of my sleep has seemed to be improved with the F20, and I've had nearly 0 major leaks three nights in a row.

When I awakened this morning, I was shocked to see my AHI = 6.65. It has never come close to that in my prior two months of therapy. My average over the last 30 days has been 1.32. There was a 40 minute period last night when my AHI was at 21. The first two nights with the F20 revealed an AHI of 0.77 and 1.46, respectively, which has been pretty normal for me. Last night, the obstructive portion of my AHI was 1.57 as compared to an average of 0.17 over the last 30 days. Also, I snored last night more than at any other time in my therapy. The graph and my burning nasal passage are evidence of this.

I had made a few changes in my apap settings with the F20 to get a more comfortable break-in experience. I changed my pressure range from 5-9 to a constant 9, and I changed my "always on" EPR from 2 to 3. Other than that, nothing has changed except the mask. Since the change in masks is the only major variable that has been introduced, could that have a significant effect on AHI?? thanks

[Julie]

You made a classic goof - changing 2-3 things at a time and then wondering what happened. You should change only one at a time so you can evaluate that feature, i.e. pressure, or mask etc. for at least a few nites each, otherwise you can't know what's what.

First of all, EPR will usually make your AHI a bit - couple of cms maybe - higher, just the nature of how it works, so if you don't need it, or don't need it at 3, lower it or turn off entirely for now.

Second, why change your pressure as you did - from Apap to Cpap, AND the numbers diff. as well? I personally would set my Apap at e.g. 7, a reasonable if lowish number that you can at least breathe at vs 4 or 5 for the min., and then let the high setting be higher at eg 15 for now... apneas won't go any higher than they need to anyway, may only reach 10, but why not open it up more, again if only for a while? And why switch to Cpap at all at the same time = to achieve... what?

Your mask may not be well fitted, or the right size, or the right type altogether for you, but again, work with it on its own while other factors remain the same so you can get definitive answers, not wild guesses. How's your leak rate? Have you set the machine's mask type into the machine (if yours allows that)? Changing the mask may or may not have been the reason, or only one, for your numbers to have been different.

[Comfortably Numb]

Thanks for your comments Julie. Here is my faulty logic. When I first tried the F20, I felt as though I was smothering. I thought if I increased my EPR from 2 to 3 and raised my minimum pressure from 5-9, I would achieve the feeling of maximum air. It does seemed to have worked in that regard. Also, my leak rates have been near 0 since moving from the N20, leading me to believe that most of my leaks were from mouth breathing. I will go back and start over. The dramatic increase in snoring is more startling to me than my AHI increase.

[zoocrewphoto]

Another possibliity to consider is that when you sleep better and relax more, you might actually need more pressure to prevent events. Some people need to increase their pressure a bit once they have settled in and can sleep better. BUT! Before you make more changes. Look at your data graphs in sleepyhead. See if your pressure is topping out at 9 or not. You said there was one period of time where it was worse. Were those obstructive events or clear airway events. Could you have been on your back, in REM, or really deep sleep? Or were you tossing and turning (possible sleep wake junk)?

[D.H.]

I agree, only change one thing at a time, so if there is any type of issue, you know which variable is the likely culprit.

[prodigyplace]

Be sure you have set your machine to full face mask.
Some people have found that higher pressures are needed with a full face mask but only make one change at a time.

[ChicagoGranny]

There was a 40 minute period last night when my AHI was at 21.

How many events did you have during that period? (See the Events tab in SH.) How many events did you have total for the night?

In both instances, what were the type of events?

[Comfortably Numb]

I'll try my best to answer each of these questions:

See if your pressure is topping out at 9 or not. You said there was one period of time where it was worse.

My pressure has been flat lined at 9 on the graph because I changed the minimum (5) to equal the maximum (9). The period of time when things were the worst applied to my AHI which was 21 for a 40 minute period. The pressure remained at 9 all night.

Be sure you have set your machine to full face mask.
Some people have found that higher pressures are needed with a full face mask but only make one change at a time.

My machine is definitely set at full face. I like an earlier idea by Julie to increase the maximum pressure to 15. I may do that and nothing else for a couple of days to see if more pressure is actually need in this full face mask.

Another possibility to consider is that when you sleep better and relax more, you might actually need more pressure to prevent events. Some people need to increase their pressure a bit once they have settled in and can sleep better.

I have definitely slept better with the full face mask because my mouth leaks have been virtually eliminated (major leaks near 0 for three nights). I have also had more dreams.

How many events did you have during that period? (See the Events tab in SH.) How many events did you have total for the night?
In both instances, what were the type of events?

My event flags were the worst I've ever had. They were as follows:
OA 9 events 1.57
H 35 events 4.83
RERA 20 events 2.74

Thanks to everyone for your help with this.

[Comfortably Numb]

Last night was my third consecutive session with a full face mask (F20). Prior to that I had been using a nasal mask (N20). The quality of my sleep has seemed to be improved with the F20, and I've had nearly 0 major leaks three nights in a row.

When I awakened this morning, I was shocked to see my AHI = 6.65. It has never come close to that in my prior two months of therapy. My average over the last 30 days has been 1.32. There was a 40 minute period last night when my AHI was at 21. The first two nights with the F20 revealed an AHI of 0.77 and 1.46, respectively, which has been pretty normal for me. Last night, the obstructive portion of my AHI was 1.57 as compared to an average of 0.17 over the last 30 days. Also, I snored last night more than at any other time in my therapy. The graph and my burning nasal passage are evidence of this.

I had made a few changes in my apap settings with the F20 to get a more comfortable break-in experience. I changed my pressure range from 5-9 to a constant 9, and I changed my "always on" EPR from 2 to 3. Other than that, nothing has changed except the mask. Since the change in masks is the only major variable that has been introduced, could that have a significant effect on AHI?? thanks

============

did you tell the machine it was pushing air into a different size mask ?

If you'll read the thread, you'll see that I have said repeatedly that my machine is set to "full face." I don't know how else to tell it what to do.

[Comfortably Numb]

I apologize xxyzx. It was in another topic/thread talking about the F20 where I said "repeatedly" that I had changed my settings to full face. I only said it once in this thread and it wasn't in the OP, so you are correct.

[WickedLoki]

If you are not going to look at the whole picture then why bother responding???

[palerider]

I apologize xxyzx. It was in another topic/thread talking about the F20 where I said "repeatedly" that I had changed my settings to full face. I only said it once in this thread and it wasn't in the OP, so you are correct.

don't apologize to someone so lazy they don't even read the thread before popping off with stupid 'suggestions'.

[ChicagoGranny]

How many events did you have during that period? (See the Events tab in SH.) How many events did you have total for the night?
In both instances, what were the type of events?

My event flags were the worst I've ever had. They were as follows:
OA 9 events 1.57
H 35 events 4.83
RERA 20 events 2.74

This is not a complete answer. I am trying to understand whether that 40 minutes wrecked your statistic for the night while the rest of the night was good.

(Don't worry about end-of-alphabet boy; he can't manage his own therapy - never had one good night of CPAP therapy in his whole life.)

[Comfortably Numb]

This is not a complete answer. I am trying to understand whether that 40 minutes wrecked your statistic for the night while the rest of the night was good.

I had events throughout the night, but there was a large cluster immediately preceding the worst period of AHI I've ever had in therapy. Between 1:15 a.m. and 1:45 a.m., I had a 29 events out of a total of 64 for the entire night. Between 1:40 a.m. and 2:15 a.m. my AHI was flat lined at 21 and then it began to recede. Not sure this is what you need.

[guest two]

do you expect me to read every message on the board before i comment on a discussion in case some stray message somewhere had some other factoid

Yes