Three weeks in - Some questions

[SleepyDwarf123]

Hello,


Background:  Had a home sleep test a few months ago and it showed an AHI of 73.8 with all apneas, except 1, being obstructive.  Completed the Titration in early Sept.  During the titration it appears that I started having Central Apneas and they moved to titrating me on BiLevel.  I have attached a copy of the table from the titration report below.  I was prescribed the AirCurve 10ST with pressure at 16/9 and backup rate of 12.  I received the machine about three weeks ago and have used it each night since.  

Since I have (historically) been a mouth breather when sleeping, they tried a Dreamwear FFM during the titration.  I found the mask to be relatively comfortable.   When I took the AirCurve home, I asked for an F30i as I wanted to try that mask.  For the first few days, I used a combination of the DW FFM and F30i.  I found them to be somewhat comfortable, but found the DW to 'burp' alot when at IPAP.  I liked the F30i, but found that I needed to make it tight and that both F30i and DW seemed to get 'sloppy' and have a hard time keeping seal later in the sleep session.  I then got my hands on an F20 and tried that for a few nights and finally got a good seal.  In the last few days, I have tried the Vitera and think that is the mask for me.  I am still working on getting the straps right, but have had a few good nights.  I agree with all that the choice of mask is probably one of the most difficult, and important, steps of getting used to therapy!

Looking at OSCAR, my leaks most nights seem to be relatively well-controlled and AHIs seem low.

I do have a few lingering questions that I hope you all can help with.

-  I have attached the OSCAR chart from last night (used Vitera).  If I read this correctly, it is showing a small number of events through the night.  When I zoom in to the flow diagram, it appears that there may be other events that are not being caught.  Am I correct in assuming that these ARE actually additional events, and if so, why isn't the machine flagging them and should I be concerned?  (I've attached a zoomed chart of one such event).

- Is it realistic to believe that the therapy has eliminated most (all?) of the obstructive apneas that appeared on the home study?  And, why didn't any Centrals appear on the home study and I had loads on the titration?

- I understand the concept of the 'backup rate' and that it is there to try to remind me to breathe when a Central Apnea occurs.  Is there a way, through Oscar, to understand how often the backup breath is used/given?

- I realize that 16 is not "too big" of a pressure, but it seems to create lots of leaks and challenges with the masks.  Is it realistic to think that if I reduced the IPAP by 1 or 2, that I would affect the AHI, etc that much?

-  For me, the biggest challenge (and really not too big) is adjusting to breathing the way that the machine seems to want me to.  By this, I mean that when I first start therapy I feel that the pressure is making me take deeper breaths.  And, I also find that when I complete the 'inhale' and start exhale, that I am 'pushing' against the machine to switch to exhale.    I had a similar feeling when switching from EPAP to IPAP and adjusted the Rise Time and that has helped, but the IPAP to EPAP switch is still abrupt.  I have adjusted Cycle sensitivity to "Very High" and this has helped, but it's still not 'natural'.   Any suggestions for making this more comfortable.

- I will be visiting my Sleep Doctor in the coming weeks for our first visit after starting therapy.  In reading this board and all of the info posted, it appears that the ST machine may not be the 'best' option.  But, if I look at my AHI with therapy, it appears that the machine is 'working'.  Would I benefit from an ASV machine and what info is best to present to my doctor to make a case?  Would the ASV be more effective, or more comfortable for therapy?

Thanks, in advance, for reading and for any suggestions/insight that you may have.  I hope I have provided the information correctly.

[SarcasticDave94]

Welcome to the Apnea Board,

I'm making a guess at this time, you must have higher Central Apnea support needs than most, or there's another Respiratory issue that prompted the doc to prescribe the ST. The progression isn't normal. CPAP or APAP like a ResMed AutoSet, BPAP like VAuto, then maybe one with backup rate for respiratory disease or Centrals.

It's good they want to get you to higher therapy machines, likely due to need, but they chose the wrong machine. ST is the old machine type. ASV will trump this soundly. You need to discuss why the ST was chosen and make your case for ASV. If you get there, request only ResMed's AirCurve 10 ASV. I'd consider harping on lack of comfort.

[SleepyDwarf123]

Welcome to the Apnea Board,

I'm making a guess at this time, you must have higher Central Apnea support needs than most, or there's another Respiratory issue that prompted the doc to prescribe the ST. The progression isn't normal. CPAP or APAP like a ResMed AutoSet, BPAP like VAuto, then maybe one with backup rate for respiratory disease or Centrals.

It's good they want to get you to higher therapy machines, likely due to need, but they chose the wrong machine. ST is the old machine type. ASV will trump this soundly. You need to discuss why the ST was chosen and make your case for ASV. If you get there, request only ResMed's AirCurve 10 ASV. I'd consider harping on lack of comfort.

Thanks for the quick reply.  I have no other respiratory issues that I am aware of (nor are noted in the Titration report or any other report).  I do plan to ask why ST was chosen and hope that the comfort issue will help.  I did have a short discussion with the doc when they called with the results of the titration and they said the ST was required because I needed the backup breaths.  This was before I was able to read all of the great info here and elsewhere.

[Gideon]

Assuming that your diagnostic study had a lack of centrals what happened is on the application of CPAP your breaths became deeper, you noted this, and as a result your body exhausted CO2, except that too much was exhausted and your CO2 levels were lowered to below your apneic threshold resulting in a central apnea . This process repeated.

Your test team put you on a BiLevel and a backup rate to combat this. Congrats on them on that they put you on sufficient pressure support to overcome the centrals. Normally we see a PS of 4 or maybe 5 which is not enough.

An ST works by maintaining both inhales and exhale pressures sufficiently far apart to encourage breaths. This is a constant value.
An ASV works by maintaining pressures to achieve a constant volume. The approach is completely different. With ASV only enough pressure will be applied to achieve this volume. The ASV reaction occurs on each and every breath that is causing a problem vs acting on all and every breath wether it is needed or not.h

[quiescence at last]

welcome to the forum, and hope you'll find experiences of those who have similar symptoms to be helpful.

i personally look for evidence of sleep efficiency, and the amount of REM and SWS (slow wave sleep), as keys to feeling sleep satisfied (quenching the body's needs).  based on those parameters the titration shows one really good setting at BIPAP^2 96% of the time sleeping versus awake, SWS occurring 50% of that sleep, and REM 14% of that sleep.  Even though BIPAP^4 shows 20 minutes of 85% efficiency, no SWS or REM occurs.

A well-known feature of adult human sleep is the abundance of slow-wave sleep (SWS) just after sleep onset with recurrent bouts of decreasing amount during the remainder of the night.

SWS is usually scored as deep sleep Non-REM or sleep stages N3 and N4.  They are usually paired with a REM sleep period, and usually occur before the REM sleep period.

I would rate the settings in order from best to good, based entirely on titration as:
BIPAP^2 (with AHI 12) lots of REM lots of SWS.
BIPAP^5 (with AHI 0)
CPAP^4 (with AHI of 14)

It would be great if the machine could self adjust between BIPAP^2 and BIPAP^5, where pressure were IPAP were 13 to 16 and PS were min 5 max 7.  I don't know much about getting those settings on your machine.

QAL


quote from 
https://academic.oup.com/sleep/article-pdf/14/1/5/13659359/140102.pdf

[SarcasticDave94]

I forgot to mention earlier, request your copy of the detailed sleep study data. This isn't the summary I'm referring to, but multiple pages with charts, written info, etc. If there's resistance in obtaining your report, make mention that HIPAA law permits you to request and receive it. No will not be the acceptable answer.

After you successfully get your copy, post a redacted version in a post on this thread. There's going to be info that will help us guide you in therapy.

I have had the ASV myself. Tuned properly, there's little Apnea that stands a chance. Central along with the other Apnea can be successfully treated with the ASV. The only weakness of the ResMed's ASV is lack of time controls, but for you I don't think that's an issue. With my COPD overlap, it was however.

And I'm thinking it can be more successful and comfortable in your situation. Call and request a switch over. And keep us updated.