Second Sleep Study - Questions to ask Doctor

[Zandor435]

I am having my second sleep study with my CPAP machine this weekend.  I have now been struggling off and on for 2-3 months with my therapy.  Folks on this board have been great.  A few solutions: Taping my mouth "fixes" dry mouth with my full face mask.  Upping my min pressure from 4 to 8.5 has helped me sleep longer through the night.  All that being said, I am still not struggling at the end of most days and sometimes earlier in the afternoon.


SleepyHead Link to 5/14/17 and 5/15/17

I would love suggestions of what to focus on with my doctor.

If possible, my goals are to ultimately be able to sleep through the night with my CPAP without any Lunesta or sleep drugs.  I would like to work towards having energy into the evening and maybe even be able to stay up until midnight some weekends. 

Currently I wake up 2-3 times a night.  I have only recently had 3-4 nights of success sleeping on my side.  I assume that is the best method for me going forward.  My AHI stays around 5. 

I would like to share my SH data with the doc.  My thoughts are to at least screenshot the last couple of weeks.  I am hoping he can help me identify with a little more certainty what pressure I need to be at and how I can best avoid OA's and H's.

From my experience I want to know the following:

Below what pressures am I having the most OA's?  What should my minimum be set at?
Is the C-Flex having an effect on my therapy?  It is set to the max of 3.  Should I work to turn that off.
What is causing my Clear Airways or Central Apneas?  (this may not be answerable as I realize this can be neurological).
Is it possible that I am being woken up by spikes in the pressure from the auto cpap?  Or is it more likely that the spikes in pressure and the waking up are both a result of clusters of OA's?

I appreciate any thoughts on other questions I might ask or maybe a better way to get the answers I  am looking for.  Thanks for any suggestions you all might have.
[url=https://goo.gl/photos/Ct9SnVTzYN8chezc8][/url]

[xxyzx]

I am having my second sleep study with my CPAP machine this weekend.  I have now been struggling off and on for 2-3 months with my therapy.  Folks on this board have been great.  A few solutions: Taping my mouth "fixes" dry mouth with my full face mask.  Upping my min pressure from 4 to 8.5 has helped me sleep longer through the night.  All that being said, I am still not struggling at the end of most days and sometimes earlier in the afternoon.


SleepyHead Link to 5/14/17 and 5/15/17

I would love suggestions of what to focus on with my doctor.

If possible, my goals are to ultimately be able to sleep through the night with my CPAP without any Lunesta or sleep drugs.  I would like to work towards having energy into the evening and maybe even be able to stay up until midnight some weekends. 

Currently I wake up 2-3 times a night.  I have only recently had 3-4 nights of success sleeping on my side.  I assume that is the best method for me going forward.  My AHI stays around 5. 

I would like to share my SH data with the doc.  My thoughts are to at least screenshot the last couple of weeks.  I am hoping he can help me identify with a little more certainty what pressure I need to be at and how I can best avoid OA's and H's.

From my experience I want to know the following:

Below what pressures am I having the most OA's?  What should my minimum be set at?
Is the C-Flex having an effect on my therapy?  It is set to the max of 3.  Should I work to turn that off.
What is causing my Clear Airways or Central Apneas?  (this may not be answerable as I realize this can be neurological).
Is it possible that I am being woken up by spikes in the pressure from the auto cpap?  Or is it more likely that the spikes in pressure and the waking up are both a result of clusters of OA's?

I appreciate any thoughts on other questions I might ask or maybe a better way to get the answers I  am looking for.  Thanks for any suggestions you all might have.
[url=https://goo.gl/photos/Ct9SnVTzYN8chezc8][/url]

i want to know why a second study is needed at all 
and if the doctor has any even distant financial relationship with the sleep lab 

now if one said you have apnea
and the next one titrates a RAD then it is possibly worth doing

[Zandor435]

My understanding is that the second study will include my CPAP machine. My first Siri did not include any CPAP machine.   My first study was about 2 1/2 months ago.

[Gideon]

I would ask 
"if I raise my Min 1cm H2O to 9.5 cmH2O do you think that will reduce my AHI?"
"my goals are to ultimately be able to sleep through the night with my CPAP without any Lunesta or sleep drugs, what is the best way to do that?"
"Currently I wake up 2-3 times a night. What is the best way to improve this"



Below what pressures am I having the most OA's?  (When you don't use xPAP your OA is highest, IMHO not a good question)
What should my minimum be set at? (What I am driving at above)  You are just above good, make only small changes

Is the C-Flex having an effect on my therapy?  It is set to the max of 3.  Should I work to turn that off. (I would try off, and settings between 1 and 3 and see if it makes a difference, this is considered a comfort setting)

What is causing my Clear Airways or Central Apneas?  (Assuming you didn't have any in your original Sleep Study, they occur because your CO2 is out of balance because the xPAP is venting CO2, the purpose of the intentional "leak" so your body says you don't need to breath, typically goes away as you get used ti therapy)
Is it possible that I am being woken up by spikes in the pressure from the auto cpap?  (Yes) [b](Some are very sensitive to the spikes)[/b]
Or is it more likely that the spikes in pressure and the waking up are both a result of clusters of OA's? (Some are very sensitive to the spikes)

[Sleeprider]

From your charts, higher minimum pressure, or a cervical collar. I think bonjour is close with his assessment of 9.5 minimum pressure. It's hard to say what the occasional periodic breathing is about without a closeup of the flow rate.

[Zandor435]

bonjour

 I appreciate the thoughts.

Below what pressures am I having the most OA's?  (When you don't use xPAP your OA is highest, IMHO not a good question)

Mainly what i meant was, at what pressure are most of my OA's dropping out.  But I agree there might be more important points to focus on.

What is causing my Clear Airways or Central Apneas?  (Assuming you didn't have any in your original Sleep Study, they occur because your CO2 is out of balance because the xPAP is venting CO2, the purpose of the intentional "leak" so your body says you don't need to breath, typically goes away as you get used ti therapy)

Bonjour, would you mind elaborating on this a little bit?  What do you mean CO2 is out of balance?  I have read a bit about intentional leak and understand it as a way of making sure you don't breathe too much CO2.  Do you mean that my mask might not be leaking enough and hence my body is responding to excess CO2?  Or do you mean that my body simply might not be used to the increased level of CO2 and that is not a problem b/c I will eventually adjust to it likely?

Btw, my[b] first sleep test did not have a CPAP, but my first sleep study report has no mention of Central Apneas.  I assume that means i had zero CA's.  [/b]

Thanks again for your comments.

Zandor 

[Gideon]

Bonjour, would you mind elaborating on this a little bit?  What do you mean CO2 is out of balance?  I have read a bit about intentional leak and understand it as a way of making sure you don't breathe too much CO2.  Do you mean that my mask might not be leaking enough and hence my body is responding to excess CO2?  Or do you mean that my body simply might not be used to the increased level of CO2 and that is not a problem b/c I will eventually adjust to it likely?

Btw, my[b] first sleep test did not have a CPAP, but my first sleep study report has no mention of Central Apneas.  I assume that means i had zero CA's.  [/b]

Thanks again for your comments.

Zandor 

the long answer
Central Apnea (CA)
Central sleep apnea (CSA) Central sleep apnea is a disorder in which your breathing repeatedly stops and starts during sleep. Central sleep apnea occurs because your brain doesn't send proper signals to the muscles that control your breathing. Central Apnea is best treated with an ASV machine. These are among the most expensive of all PAP machines. On an xPAP the best we can do is to minimize the Max pressure and utilize EPR or other relief (PS on BiLevel / BiPAP)if available, at the same time as raising the EPAP (min Pressure) to support obstructive events. These two treatments “fight” each other and it is a real balancing act. If an Auto band is used it is typically a very tight band.

The below is from RobySue from a forum post with minor edits by bonjour
When a PAPer is reporting problems with centrals while on xPAP, the important questions come down to these:
1) Did the sleep diagnostic test (the one without xPAP) show any centrals?
2) How many centrals are we talking about and at what pressure(s) do they start?
3) Can the OSA stuff (the OAs, the Hs, and most of the snoring) properly be treated at a pressure level that is below that needed to trigger the CAs?
4) Does the number of CAs go up, down, or stay about the same after a few weeks on xPAP therapy?

Here's the thing you need to be aware of: Some people's bodies do have a bit of a problem regulating the CO2 levels in the blood when they are first put on xPAP therapy for obstructive sleep apnea. And the result of not properly regulating the CO2 level in the blood leads to the emergence of central apneas. Essentially, you only inhale when the CO2 level in the blood is high enough for your brain to tell the lungs and diaphragm, "Inhale Now". When the brain misinterprets the CO2 level or if the CPAP washes out too much CO2, the brain doesn't send the signal to "Inhale Now" and you don't take a breath when you are supposed to take one.
The problem with pressure-induced centrals seems to be aggravated by the addition of pressure. In other words, the higher the pressure setting on the xPAP machine, the more likely pressure-induced centrals are to occur. In some people, the CAs can be completely controlled simply by limiting the max pressure the machine is allowed to use. Pressures over 10 cm are more likely to cause problems with CAs, and hence if the OSA stuff is controlled with a pressure less than 10, the usual fix is to just use only enough pressure to control the OSA stuff. (A few people have trouble with pressure-induced centrals at lower pressures; other people find that their pressure-induced centrals might only be a problem if the pressure is really high--like above 15cm.)
Sometimes the problem with pressure induced centrals is self-limiting: The body takes a while to figure out the whole xPAP thing, but after a few weeks it *does* adapt and by that point many people who had some issues with pressure-induced CAs notice that the number (and length) of the CAs in their data starts to decrease. And after a few more weeks of using their machine, the CAs essentially disappear---in other words, the person gets some isolated ones here and there, but the number of them is small and the overall AHI is consistently less than 5 (and often significantly less than 5) and the person reports feeling and functioning better in the daytime. The fact that many people's bodies take a while to adjust and that the number of CAs recorded often goes down with continuing to use the machine is a major part of why many sleep docs and most insurance companies don't just immediately switch an xPAP newbie from a CPAP/APAP or BiPAP/VPAP to an ASV machine at the first sign of pressure-induced centrals. Other reasons for not immediately switching include the cost of an ASV and the fact that learning how to sleep with an ASV can be much harder than learning how to sleep with a CPAP/APAP or BiPAP/VPAP due to the drastic pressure increases used to "trigger" inhalations as a way to prevent the central apneas.
Given that you are seeing some centrals and your overall AHI is sometimes in the 5-10 range instead of the 0-5 range, it's worth watching the centrals, but it is also worth giving your body some time to adjust to the AirCurve. And if you jumped from the AirSense to the AirCurve right away because of the centrals, then it really may be best to be patient for 2-4 more weeks of using the AirCurve with your current settings.
It's also worth mentioning that some people find that frequent changes to the therapeutic settings aggravates their problems with centrals. In this case, two important questions to ask are:
A) How long have you been using xPAP? (In this case, that means both the time you used the AirSense and the time you've used the AirCurve.)
B) How frequently do you change the settings? What is the longest you've used a particular setting?

[Zandor435]

Bonjour,  

It will be some time before I can respond in full, but this is awesome.  I am very grateful for the response.  This is a lot of great information.  Thanks for taking the time to answer my question.  I still can't believe how helpful you and others have been on this board.  Thanks again. 

Zandor

[David Govan]

Bonjour,

Many thanks for the long, thoughtful dissertation. Two questions --

With total AHI under 5, consistently, what number of CA's should give concern?

With total AHI under 5, what does the great predominance of hypopneae suggest?

I realize these are very general questions.  

Thanks.

[SideSleeper]

PR machines have two Flex settings--C and A. The difference has been explained on this forum but I can't remember how to explain it--just know I had more CA's on C Flex. My CA's, pretty regular when I first started, were also lowered when I dropped from 3 to 1.