No Answers Yet For Problems With ASV

[Paper_Nanny]

I had an appointment with Mister Sleep Doctor (MSD) today. Long appointment... Very interesting appointment. I took Husband with me for moral support. I asked him afterwards if he noticed how MSD kept giving me non-answers to my questions and if he noticed how much MSD dislked me. Husband said he thinks MSD was being evasive because he doesn't feel comfortable saying, "I don't know the answer to that" He said, "I don't think MSD dislikes you; I think you frustrate him because you keep making him say he doesn't know the answer."

Some of my friends who have chronic illnesses and I joke about doctors being one of three types. There are the ones who are wonderful to work with, right from the very first appointment. There are the ones who are trainable. They are a little difficult at first, but can be trained so they are okay to deal with. And there are the untrainables. I would classify MSD as "trainable" at this point and today's appointment was a very long training session with him.

End results of the appointment: I will be having a full set of Pulmonary Function Tests done in a few weeks, if for no other reason than to establish a baseline against which future testing can be compared, if the ms starts having an effect on my ability to breathe.

I will be changing the settings on my machine so that it is set to BiPAP mode, with pressures of 8/12. Yeah, it sounds crazy, but it might work.

MSD talked to Bob, the Respironics Rep for much of the state of Oregon. Bob did in fact say I should be on a straight BiPAP, with no ASV. Why does this make sense? According to Bob, the the ASV is causing me to hyperventilate. That causes the CO2 level in my blood to go down, supressing the urge to breathe. When the CO2 level goes up, then I breathe. But, the ASV thinks I should be breathing sooner than that and triggers a breath. Thus, the PTB rate goes down after the first few hours of sleep.

Why does the ASV do that? Doesn't the algorithm figured out how fast I was breathing and time the breaths accordingly? According to Bob, that isn't quite right. The algorithm was deisgned for people with Cheyne-Stokes Respiration and CSA secondary to the use of opiods. It works great for people with that sort of SDB, but not for people like me.

I am not exactly sure how the residual hypopneas fit in there, but for now, I'll just go along with the notion that they somehow fit in to the nongeneralizability of the ASV algorithm. Bob will be sending MSD information about that. MSD will be passing that information along to me. And I will be passing it along to people here. It's like a little information train!!

When MSD called to tell me all that, he said he would call my DME tomorrow so she could change the setting on the machine. I told him he didn't need to bother, that I could take care of it myself. He said he didn't care what I did with my machine, but that he needed to call the DME to do the changes. I guess that makes sense with all the Right and Proper Medical Laws and Other Rules about such things.

I will be taking my machine in to the DME tomorrow anyway. I'm trading it in for the new lighter weight machine with more humidifier settings. Oh, yeah, I almost forgot... It also has wave form data capabilities.

I'll keep ya'll posted on what happens as a result of the changes in machine settings.

Deborah

Edit #1: Added information about machine settings.
Edit #2: Removed information about machine settings to put in separate post.

[Paper_Nanny]

These are the settings on my machine. Based on an earlier post by BrianinTN, these should set my machine up to act like a regular BiPAP set at 8/12. Brian didn't say anything about flex in his post. I left my flex set at 2. Will this make any functional difference?

BPM= 0 (Auto Off)
PresMax= 12
EPAP Max= 12
EPAP Min= 8
PS Max= 4
PSMin= 4
Flex= 2

Deborah

[dsm-guested]

These are the settings on my machine. Based on an earlier post by BrianinTN, these should set my machine up to act like a regular BiPAP set at 8/12. Brian didn't say anything about flex in his post. I left my flex set at 2. Will this make any functional difference?

BPM= 0 (Auto Off)
PresMax= 12
EPAP Max= 12
EPAP Min= 8
PS Max= 4
PSMin= 4
Flex= 2

Deborah

Deb,
Flex is an ease-of-use setting. It softens the transition from one breathing state to the other (breathing in-out) 2 is a good starting point. It shouldn't create any issues.

Good luck

DSM

[NotMuffy]

I asked him afterwards if he noticed how MSD kept giving me non-answers to my questions and if he noticed how much MSD dislked me. Husband said he thinks MSD was being evasive because he doesn't feel comfortable saying, "I don't know the answer to that" He said, "I don't think MSD dislikes you; I think you frustrate him because you keep making him say he doesn't know the answer."

Well, "IMHO", you could have really lit him up if you waved your Diagnostic Sleep Study at him



and asked a few techno-questions like:

• "On this NPSG, it looks like the majority of events are central apneas in REM. Aren't central apneas frequently considered a normal phenomenon in REM, especially Phasic REM?"
• "As a matter of fact, isolated centrals, especially if they are post-arousal, may also be considered a normal response?"
• "And if remove the central apnea index (3.8) from the Total AHI (7.0), then the Obstructive Apnea Index (3.2) doesn't even qualify me as 'mild', but rather 'normal'?"
• "Isn't it a little unusual (although not impossible)to have zero associated snoring in an OSA patient?"
• "However, in the absence of snoring, does that not make the liklihood of the hypopneas being central a very strong possibility as well?"
• "Is there even a relationship between the desaturations and respiratory events? The worst desat (at 84%) isn't."
• "Since respiratory events are almost always terminated by an arousal (although Magdy would certainly be willing to debate this), how is it that with my calculated number of respiratory events (41), there are only 11 arousals (coincidently, 41 desats. Otherwise they really wouldn't be events)?"

I will be having a full set of Pulmonary Function Tests done in a few weeks, if for no other reason than to establish a baseline against which future testing can be compared, if the ms starts having an effect on my ability to breathe.

You should also get a set of Maximum Inspiratory and Expiratory Pressures. Arrange this beforehand to insure they get the "thing".

I will be changing the settings on my machine so that it is set to BiPAP mode, with pressures of 8/12.

The logical progression would then be to try some low level CPAP, which should have been done in the first place. It is quite effective at taking a normal Obstructive AHI and turning it into a...

a...

... well, at least it can do it a heckuva lot cheaper than an ASV.

[NotMuffy]

...But now I see your avatar and I wonder, is Muffy a reference to a baked goods product?

Correct.

I am a "baked goods" that got snatched up during The Rapture.

[avi123]

[quote="NotMuffy except blueberry!

[*]"However, in the absence of snoring, does that not make the likelihood of the hypopneas being central a very strong possibility as well?"
a...


Question to NotMuffy: are the Hypopneas distinguished during PSG if Central or Obstructive?



... well, at least it can do it a heckuva lot cheaper than an ASV.[/quote]


Question to NotMuffy: Isn't an ASV a bad choice for an MS patient?

[Paper_Nanny]

Question: are the Hypopneas distinguished during PSG if Central or Obstructive?[/color]

I don't see anywhere that distinction is made, but I may be missing something.

Question: Isn't an ASV a bad choice for an MS patient?

Why would they necessarily be a bad choice for someone with MS? The areas of damage that can occur in MS are so incredibly variable that I don't think blanket questions like that make much sense.

Can you add some detail to your question, such as, "Isn't an ASV a bad choice for someone with MS who has________?" That would make more sense.

Deborah

[Paper_Nanny]

Well, "IMHO", you could have really lit him up if you waved your Diagnostic Sleep Study at him and asked a few techno-questions

Feeling a bit like an idiot after reading all that. Yeah, that probably really would have rattled his cage some. Alas, those questions never even occurred to me.

You should also get a set of Maximum Inspiratory and Expiratory Pressures. Arrange this beforehand to insure they get the "thing".

Which "thing"?

Deborah

[Paper_Nanny]

I woke up this morning feeling better than I have in days. There was a slight glimmer of a chipper and perky feeling in my belly. And when I looked at my data from last night... Whoa!!! WTF??? It looks HORRIBLE!!! I am now skeptical about this answer to my problems.

[BrianinTN]

The numbers are possibly indicative of ComplexSAS (i.e., central apneas in response to higher pressures). It's possible that lots of those new hypopneas are also central in nature.

These are higher "static" pressures than you're used to having. If we are seeing ComplexSAS, your body may acclimate with a bit of time, and those numbers may come down. Or it may not. Guess what the treatment of choice is for ComplexSAS? Yep, you guessed it, ASV.

My advice would be to (1) call your doc and tell him both how you feel and what the numbers are, and (2) ask him whether you should stick it out to see if things improve or immediately adjust the settings. There's a pretty strong argument for sticking it out, especially since you felt good, but I have no idea whether the MS makes it inherently risky to induce these kinds of centrals.

Unrelated to the above, I find it odd that the ASV sometimes did make slight changes in EPAP and IPAP. I didn't think it would do so given the parameters you entered.

Question: are the Hypopneas distinguished during PSG if Central or Obstructive?[/color]

I don't see anywhere that distinction is made, but I may be missing something.

No, you aren't missing anything. Quoting yet another email from my RPSGT friend, who was grumbling about this very issue:
"...older style of designating events, which was more precise, where events are categorized as obstructive, central, or mixed in addition to the designation of apnea, hypopnea, RERA... but they don't officially recognize those multidesignations anymore"
I've gathered from reading on the binarysleep boards that some labs still do and some labs don't. Muffy can probably explain why that's the case.

[rested gal]

Glad to see Not_Muffy is helping you, Deborah.

I had heard of "phasic" (and "tonic") REM before but had never looked it up.

Found this:
http://www.rtmagazine.com/issues/articl ... -02_04.asp

[StillAnotherGuess]

There are the ones who are wonderful to work with, right from the very first appointment. There are the ones who are trainable. They are a little difficult at first, but can be trained so they are okay to deal with. And there are the untrainables.

If I were your sleep doctor, how would you classify me?

MSD talked to Bob, the Respironics Rep for much of the state of Oregon. Bob did in fact say I should be on a straight BiPAP, with no ASV. Why does this make sense? According to Bob, the the ASV is causing me to hyperventilate. That causes the CO2 level in my blood to go down, supressing the urge to breathe. When the CO2 level goes up, then I breathe. But, the ASV thinks I should be breathing sooner than that and triggers a breath. Thus, the PTB rate goes down after the first few hours of sleep.

You feel better because you have 100% PTB while not on ASV. But the AHI sucks. Your AHI was better on ASV. If what Bob says is true, I would still love to bag you and add O2 to your ASV therapy. Maybe that could keep your AHI low and still have 100% PTB?

[Paper_Nanny]

If I were your sleep doctor, how would you classify me?

I don't have enough information to answer that question. How would you like me to classify you?

I would still love to bag you

Wow, I have never had a guy say that to me before! It sounds kinda... creepy. I can't get the body bag sensations out of my mind. The sound of the zipper, the feel of the plastic, the weight of the bag with someone inside... <looking around, trying to find the shuddering smiley>

But I digress. Why would adding O2 to my therapy make a difference?

Deborah

[Paper_Nanny]

These are higher "static" pressures than you're used to having. If we are seeing ComplexSAS, your body may acclimate with a bit of time, and those numbers may come down. Or it may not. Guess what the treatment of choice is for ComplexSAS? Yep, you guessed it, ASV.

I feel like I am in some weird cartoon for deranged middle school children.

My advice would be to (1) call your doc and tell him both how you feel and what the numbers are, and (2) ask him whether you should stick it out to see if things improve or immediately adjust the settings. There's a pretty strong argument for sticking it out, especially since you felt good, but I have no idea whether the MS makes it inherently risky to induce these kinds of centrals.

Doctor left the office at noon today and is on vacation until 11 July. He went to Lake Shasta. I could probably track him down. I don't no of any risk inherent to MS associated with those kinds of apneas. Maybe I will just leave it be until Doctor comes back from vacation.

Unrelated to the above, I find it odd that the ASV sometimes did make slight changes in EPAP and IPAP. I didn't think it would do so given the parameters you entered.

Once again, you have examined my data more thoroughly than I did. I may have noticed that later this evening, or tomorrow, but hadn't done more than give it a cursory glance this morning.

Deborah

[StillAnotherGuess]

Why would adding O2 to my therapy make a difference?

It would only make sense if you plugged the vent holes in your mask (i.e. bagging you) in conjunction with supplemental O2 and ASV therapy. Without this process you will never use your device successfully in ASV mode.

Read carefully what you wrote that Bob said.. Then read it again.

'Guest' and everyone one else will strongly disagree with me. So be it.

They will all agree your ASV days are over.