Apnea Board Forum - CPAP | Sleep Apnea
Good results, except sometimes at end of night - Printable Version

+- Apnea Board Forum - CPAP | Sleep Apnea (https://www.apneaboard.com/forums)
+-- Forum: Public Area (https://www.apneaboard.com/forums/Forum-Public-Area)
+--- Forum: Main Apnea Board Forum (https://www.apneaboard.com/forums/Forum-Main-Apnea-Board-Forum)
+--- Thread: Good results, except sometimes at end of night (/Thread-Good-results-except-sometimes-at-end-of-night)



Good results, except sometimes at end of night - marklang - 02-22-2019

I have been having good success with my sleep apnea after earlier support on this forum.  I am using a Resmed Aircurve 10 vAuto machine set initially to 16/20 bipap and going up to 19/23 when needed.  I use a Resmed F20 full face mask.   Most of the time I have very good results:  often 0 (no incidents), and usually below 1 over about 7 hours of sleep.  However, in the last month or so I have been noticing that, from time to time, I have very good results for most of the night, but I get a lot of obstructive apneas and hypopneas the last hour or so of the night.   See the data from Sleepyhead below:

[attachment=10395]

I wear a collar all the time (Caldera) because I had problems even with those high pressure settings without one.   Initially, the Resmed bipap and collar combination took me from terrible results to very good results.   Even with the collar, however, I am getting these unusual results probably about once every 2 weeks, sometimes a bit more often.  I usually sleep for 4-5 hours after going to bed before I first wake up.  After that, I usually only go for an hour or two before I wake up again.   The problems always occur in the last sleep period of the night, and sometimes also in the one before that.  As can be seen in the data attached, for the last hour of this night I had problems almost every minute, after having no problems for most of the night.   That is similar to what I had before using cpap (average of 55 incidents per hour in my first sleep test).  

Does anyone have any idea what is going on here?  I am still sleeping well for most of the night, so I guess this is not too bad of an issue.   My sleep doctor says the results will vary from time to time.  However, I would like to get beyond this last issue if I can.  Thanks for any advice you may have.


RE: Good results, except sometimes at end of night - Gideon - 02-22-2019

I see the problem occurring 3 times in the above chart, during your last 3 sessions of the night, each starting approximately the same amount of time after going back to bed, and each successive time is worse than the previous time.

The issue is Flow Limits, the question is why?

Post a "normal typical night" for comparison and post 3minute detailed views leading into each event to help see if we can see a reason.

A possibility is to raise your PS from 4 to 5 to see if that impacts the Flow Limits.  I assume that you were wearing the collar for all sessions, they do look positional at first glance.

Fred


RE: Good results, except sometimes at end of night - marklang - 02-22-2019

Here is a view of the very next night.   This is pretty typical of most of my nights.

[attachment=10399]

Here is a close up of the start of the first cluster on the previous bad night, in my second from last sleep period:

[attachment=10400]

Here is a close up of the second cluster in my last sleep period. 

[attachment=10401]

The Resmed unit shows flow restriction, and it does look a lot like I used to get without the collar (positional).  However, I was wearing the collar and sleeping in the same position as far as I can tell all night.  

I have never really understood how to set the PS pressure support.   In my bipap sleep test, they used only 4, and I have kept that since.   I can try leaving the maximum pressures the same but increasing the PS to reduce the lower pressures. 

Thanks.


RE: Good results, except sometimes at end of night - Gideon - 02-22-2019

Just change PS to 5, no other changes.

Settings are
Min EPAP the starting EPAP pressure
Max IPAP the pressure that will not be exceeded
PS the amount of pressure added to the actual EPAP to equal the actual IPAP

The algorithm will alter EPAP and the IPAP will be maintained by the amount of PS above EPAP thus IPAP = EPAP + PS
Increasing PS is one way of treating hypopneas and flow limits with a bilevel (vauto)

I see the same issue in your typical night though at a very much lower level. See if you can video yourself for at least the start of all your sessions, I think something around 10 minutes+/- is your critical time.


RE: Good results, except sometimes at end of night - marklang - 02-22-2019

Thanks. I will try the PS change. I will need to figure out how I might video myself.

I have noticed that there are indications of flow restriction even on my good nights. The Resmed seems to respond very quickly to what it sees as flow restriction -- within a few breaths. So it often reacts even before an apnea event is recognized. The Dreamstation I had when I started with Cpap took many minutes to respond. It was advice from this forum that led me to request the Resmed when I switched to Bipap, and I am very glad I did that. My doctor prefers Dreamstation, but he let me go with the Resmed when I asked for it.


RE: Good results, except sometimes at end of night - marklang - 02-28-2019

I have not had this issue since I switched the PS on my machine to 5 until last night.   However, I really think it is not the machine setting.   Last night I slept the first period till about 1 am.  I went back to sleep and woke up again about 3:40 am, with no problems.  However, when I went back to sleep that time about 3:47 am, I had 27 events between then and 4:55 am.  This time, however, after I got back to sleep around 5 am I had no more incidents until I finally got up at 5:45 am.  

The second time I got up I noticed the high AHI reading on the machine.   This time I plumped up my pillow and laid down as I do when I first go to bed.  (I have normally just laid back in bed on the pillow as is when I wake up during the night.)  This suggests there is some kind of positional problem that the Caldera collar is not preventing.   I have not figured out a way to video me all night.  I could speculate that perhaps I am moving my head to the side, but I am not sure that would cause flow restriction.  I am using a special pillow filled with fibers of memory foam.  Perhaps in some circumstances the pillow takes a shape during the first part of the night, and I happen to lay down on it in such a way to push my head forward against the collar.   The collar is foam and will give some.  

I attached the data expanded at about 3:55 am.  This is a few minutes after I went back to sleep around 3:47 am and where the problems really show.  

[attachment=10562]

Any further suggestions are appreciated.   Perhaps I should try a different collar???  Again, while I have some indications of issues, this really bad cluster of events does not happen except occasionally, and I can determine no pattern.


RE: Good results, except sometimes at end of night - Gideon - 02-28-2019

You are understanding what is happening. I would suggest that when you are so that you re-fix your pillow as if you are just going to bed.

Remember that 1 night does not make a trend, thus I would not recommend any other changes for now.


RE: Good results, except sometimes at end of night - marklang - 02-28-2019

Thanks.  I agree that one night does not make a trend.   Fortunately, I am doing pretty well most of the time.  Nevertheless, I have this one issue that comes up regularly if not consistently, and I would like to deal with it.  I seem to be very sensitive to position.


RE: Good results, except sometimes at end of night - Gideon - 02-28-2019

The changes would be to a stiffer, or a taller collar or both.  A change in pillow, by itself, or coupled with the previous suggestions.


RE: Good results, except sometimes at end of night - marklang - 04-14-2019

Sorry for the delay in responding.   I purchased a new collar from Futuro, which was actually available from the local CVS drugstore.   It is thicker with a more rigid foam than the Caldera collar, although still reasonably comfortable.    That collar seemed to take care of the issues.   I also purchased a new pillow, a Tri-Core from Core Products.   This pillow has a depression in the center so the neck is supported by the fairly rigid side and the head sinks down into the depression.    This pillow alone did not work for me.   However, with the new collar and pillow, I have not had the bad results later in the night.  I still get up to 6-8 incidents on some nights, but my averages over a normal 7 hours are almost always below 1.   That is probably just normal variations.    So I guess this issue was just another indication that I am very sensitive to sleeping position. 

Thanks again for all the help.