Interesting discussion of CSA as it relates to OSA . . .

Talking Sleep - Spotlighting Central Sleep Apnea https://aasm.org/wp-content/uploads/202 ... script.pdf

From that discussion/interview:

"I would posit that . . . the relationship between central and obstructive sleep apnea is very tight from a pathophysiologic standpoint. These two conditions are very much intertwined."

"Many of my colleagues and our trainees . . . talk about . . . post arousal. They see a huge breath, and there is an apnea after that. . . . Now, if that's all I see, I'm prepared to downgrade it and not consider it contributing to the overall picture. But again, it all depends on how many of these we see."

"My approach [to treatment-emergent central apnea]--and this is one area when data are few, experts are many-- . . . I look at the level of CPAP that eliminates the obstructive apnea and treat it . . . And if after three months [the centrals go] away, we're done, which is probably the natural history in a good number of patients. Now, there are a number of people who would continue to have some [central apnea]. Our approach has been on not overtreating. . . . If . . . around 15 they're not symptomatic, leave them alone. If it's more than 15 and it persists and they're symptomatic, then I think we need to bring them back. And we do either ASV or BiPAP. . . . But I like to give them time on CPAP, get them to accept the CPAP, use the CPAP. Make sure there is nothing else, heart failure, whatever, and then reassess them."

Edits were to typos, some mine and some in the (automated?) transcript.

Are they using CSA (Central Sleep Apnea) and CAA (Clear Airway Apnea) as exactly synonymous terms?
For example: Any detected clear airway apnea event is a detected central sleep apnea event.

Yes, very interesting*
IMO, a summary statement made at the very end is highly significant:

DR. BADR: The message is that we need to think of ventilatory drive of central apnea as the
headline, not a footnote. It is really a driver in the whole condition under the rubric of sleep disordered breathing.
And that morphologic distinction that we draw in international borders or firewalls
between central apnea and obstructive apnea,
I think it's arbitrary and artificial and may not be benefiting our patients.

So if we think of it as an unstable system with an unfavorable upper airway, it will manifest as obstructive apnea,
{but} an unstable system with a favorable upper airway. It will manifest a central apnea.
It's one system that that is showing you instability.

(Highlighting and brackets were added for clarity)

@ Lazarus: Do you think that the "it" that Dr Bader is referring to in his last sentence "It's one system that is showing you instability" is the ventilatory drive system?

Probably broader.

The point is that giving optimized CPAP the full shot for months can often solve the centrals too, since the physical airway and the drive mechanisms are all interrelated as part of one big system. Fixing the obstruction issues by stabilizing the airway will often fix centrals because of that system interplay. People need time to heal once the CPAP is put in place. Rushing people to some other modality before giving that healing and adjustment time to happen on CPAP is not helpful. If the centrals remain a significant number or get worse or disturb sleep, THEN it is time to explore.

So please stop telling people that having some centrals when they start on CPAP is reason to panic and begin searching for serious health issues and demanding a different machine. The centrals may be nothing more than a different manifestation of OSA. Let the CPAP treat the OSA for a while first since CPAP doesn't only stabilize the airway but also can, for many, stabilize any emergent or uncovered drive glitches that the years of untreated OSA caused.

Unless, of course, you are in the business of pushing ASVs onto people who don't need them.

Tec5 wrote: ↑

Tue Aug 22, 2023 8:12 pm

Are they using CSA (Central Sleep Apnea) and CAA (Clear Airway Apnea) as exactly synonymous terms?
For example: Any detected clear airway apnea event is a detected central sleep apnea event.

They have no problem understanding the meaning of terms they use because they know how to use context to discern the intent behind the chosen terminology instead of needlessly getting hung up on meaningless technicalities.

I highly recommend we all learn to do the same.

But, yes, it seems the doc's stated preference is repeat lab PSG. Nevertheless, the doc uses home-machine-reported data because of unwillingness of patients to do a repeat PSG.

Similarly, when they say BiPAP, they mean bilevel, since the context isn't an attempt to differentiate between brands.

My choice is to read for intent and meaning, not enforcing one's own preferences for word choices onto others.

lazarus wrote: ↑

Wed Aug 23, 2023 12:02 am

Tec5 wrote: ↑

Tue Aug 22, 2023 8:12 pm

Are they using CSA (Central Sleep Apnea) and CAA (Clear Airway Apnea) as exactly synonymous terms?
For example: Any detected clear airway apnea event is a detected central sleep apnea event.

They have no problem understanding the meaning of terms they use because they know how to use context to discern the intent behind the chosen terminology instead of needlessly getting hung up on meaningless technicalities.

I highly recommend we all learn to do the same.

Your preferred context, is not the only “context”. One would expect that specialists speaking to other specialists would be very precise in their wording, to avoid misunderstanding by someone inferring an alternate “context”.

But, yes, it seems the doc's stated preference is repeat lab PSG. Nevertheless, the doc uses home-machine-reported data because of unwillingness of patients to do a repeat PSG.

I did not ask about the docs preference to repeat in-lab PSG, what point are you trying to make here?

Tec5 wrote: ↑

Wed Aug 23, 2023 7:00 am

Your preferred context, is not the only “context”.

My point is that the writer's/speaker's context is the one that matters. Not yours. Not mine. I mean, if you are interested in information at all, anyway, not just meanings of words.

Tec5 wrote: ↑

Wed Aug 23, 2023 7:00 am

One would expect that specialists speaking to other specialists would be very precise in their wording

I wish you the best with that expectation. But you may want to get used to disappointment.

Real respected experts exchange concepts without attempting to police one another's usage to an unreasonable level of false exactness.

Learn to round each word to the nearest meaning as you read and listen, instead of demanding that each word have a decimal point followed by three numbers.

Or not.

Tec5 wrote: ↑

Wed Aug 23, 2023 7:00 am

I did not ask about the docs preference to repeat in-lab PSG, what point are you trying to make here?

Look at the context and the meaning for hints about what I meant.

lazarus wrote: ↑

Wed Aug 23, 2023 7:27 am

Look at the context and the meaning for hints about what I meant.

And that, kind sir, is exactly what I'm addressing.
You are asking me to interpret ("look for hints") to decode what you mean, as opposed to just explaining what your point is intended to be.

My interpretation of what you mean to convey, is not necessarily what you intend. But you can clarify, if you choose.

You asked about synonymous terms. Again. For some reason. Which is fine. Although it has nothing at all to do with why I posted what I posted or why the doc interviewed said what the doc said, as best I can tell.

But I'll address it one more time before I give up.

As I read it, the doc interviewed discussed lab findings AND home machine findings at one point in the interview, BOTH mentioned in the context of a discussion of centrals, but expressing a preference for what a lab finds over what a home-treatment machine finds--for obvious reasons involving the limitations of the valuable info that treatment machines provide for assessing and optimizing breathing.

From the interview:

We used to bring them back for another sleep study, another polysomnogram. But many patients don't like to have to come back for this, so we actually rely on tele monitoring, on our remote monitoring, because I think it's pretty good.

That well illustrates the facts of how definitions of words are not the, uh, central points. One word can often have a spectrum of meanings, much as human beings can often appear to lay along spectrums themselves when it comes to obsessions about word meanings in varying contexts.

PSG is pretty great for assessing centrals, home machines are "pretty good." Neither is perfect. But the same word can be used, if someone wants to. "Centrals."

When a clinician or researcher is broadly discussing the forest, good listeners don't become overly distracted and confused by which exact trees are meant. They infer that from the context of which forest in which location is being discussed. And that way they learn without confusing themselves and others. Therefore I ignore what term a speaker/writer uses to discuss seemingly-non-obstructive pauses in breathing, listening instead for intent, meaning, and practical application. And I recommend others do the same.

Hope that explains well enough why I said what I said. If not, I apologize for my explanatory limitations in my posts. I do the best I can.

And now can someone please help me resurrect my poor horse that appears to be somewhere along the death spectrum?

(Do you mean merely that the horse stopped breathing as assessed by the rider, or that an actual horse doc was called immediately to the scene to make an official pronouncement? Because only THAT would be a REAL death!)

lazarus wrote: ↑

Tue Aug 22, 2023 11:45 pm

So please stop telling people that having some centrals when they start on CPAP is reason to panic and begin searching for serious health issues and demanding a different machine.
Unless, of course, you are in the business of pushing ASVs onto people who don't need them.

I don't know that I've ever told that to people who are having some clear airway events*.

I've consistently commented that folks should try to find the causation of clear airway events to satisfy themselves that their is no pathological causation..... when the CAE are disproportionately large as compared with obstructive events. One way to do that is to discuss the clear airway events with their doctor, and I'd add probably the preferred way. The answer may be as simple as post-arousal apnea (whether the patient is consciously aware or remembers an arousal or not). But what patients should NOT do, in the face of significant numbers of clear apneas, is ignore it.

* I prefer to use the term clear airway events, as that is the broad descriptor for the clinical sign used in OSCAR reports, and the only clinical sign that home machines can distinguish.

And I prefer the terms RAHBD and VAHBD.*

Rider-Assessed Horse-Beating Death and Vet-Assessed Horse-Beating Death.

Hey, just me.

But it seems the doc interviewed above doesn't worry about any of it much until (1) after three months or so on PAP and (2) C-AHI is above 15 and (3) they're still symptomatic. That's pretty stinking conservative rather than aggressive about treating nonobstructive AHI. Not sure I'd buy into that approach 100%. But I respect it. And hopefully none of that doc's patients come here during that process and get frightened by posters making blanket statements about which machines treat which events and about how all pauses in breathing need immediate in-depth investigation.

After all, part of 'not substituting for medical advice' is not feeding people's fears when they see their machine reports and jump to conclusions about the medical significance. 'Talk to your doctor about this immediately' can be very scary words for an already frightened newbie to hear.

Just sayin'.

lazarus wrote: ↑

Wed Aug 23, 2023 12:22 pm

After all, part of 'not substituting for medical advice' is not feeding people's fears when they see their machine reports and jump to conclusions about the medical significance.

Yep, that's what I've been trying to impart, leave it to your medical professional to determine medical significance, not some randos on the internet.

'Talk to your doctor about this immediately' can be very scary words for an already frightened newbie to hear.

I don't think I've ever told someone "talk with your doctor immediately", but if you can find somewhere that I've said "immediately" I'll be glad to apologize.

By the way, I am not " in the business of pushing ASVs onto people who don't need them" . No, not in the business of "pushing" any equipment, let alone to people who don't need something.

dataq1 wrote: ↑

Wed Aug 23, 2023 1:36 pm

not some randos on the internet

I don't really know much about Rando, personally. But if I happen to cross paths with him in this forum, I'll do my best not to draw first blood.

@lazarus
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