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Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 4:13 pm
by Rubicon
Yeah I'd look at the graphs, specifically the desats. They used the 4% rule, I think they're valid, but the mean nadir is only 92%.

Is the 82% real or artifact? If there's only like 1 significant desat out of the clear blue sky I'd be thinking about throwing it out.

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 4:20 pm
by lazarus
Rubicon wrote:
Wed Jan 11, 2023 3:48 pm
Rubicon wrote:
Wed Jan 11, 2023 3:46 pm
You heard weed is legal here now?
Going over to CostCo now to pick up a bale.
Be nice to your lungs. You might need them later.
Centennial1 wrote:
Wed Jan 11, 2023 2:51 pm
the care that has to taken in comparing AHI from the WatchPat and a AHI from your home machine is that the one infers/implies apneas while the other actually detects apneas and hypopneas ..... is that fair to say?
I would say that lab/center AHI is true AHI. Home-treatment-machine-reported AHI is a useful estimation/approximation for trending purposes. And pAHI is a different estimation/approximation suitable for home diagnostic purposes.

Scientifically and technically speaking, none of the three are directly equivalent. But that's OK. Other than in exceptional circumstances, the estimation/approximation versions of AHI are plenty good enough for the purposes for which they're designed.

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 4:42 pm
by Rubicon
lazarus wrote:
Wed Jan 11, 2023 4:20 pm
And pAHI is a different estimation/approximation suitable for home diagnostic purposes.
Y'know you can trick a WatchPAT into thinking PLMs are pAHs:


Image

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 4:46 pm
by robysue1
Rubicon wrote:
Wed Jan 11, 2023 4:42 pm
lazarus wrote:
Wed Jan 11, 2023 4:20 pm
And pAHI is a different estimation/approximation suitable for home diagnostic purposes.
Y'know you can trick a WatchPAT into thinking PLMs are pAHs:
So does that mean that if a WatchPAT study indicates there may be OSA, then it's prudent to follow up with an in-lab sleep study?

What if a WatchPAT study seems to indicate that OSA is not likely a problem. Does that mean it's prudent to follow up with an in-lab sleep study?

In other words, what's the real benefit of a WatchPAT study? Other than the obvious that it's cheap and done in your own bed?

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 5:22 pm
by lazarus
Rubicon wrote:
Wed Jan 11, 2023 4:42 pm
Y'know you can trick a WatchPAT into thinking PLMs are pAHs:
I am not really a fan of HSTs in general, myself. But if the only way payors will allow trials of PAP is by using positive-finding HSTs, I will try my best to support the AASM stand on it all. I guess.

I consider my personal printouts of my lab diagnostic and lab titration some of the most valuable documents I own. But present economic reality just doesn't seem prepared to support the providing of that to all who need lifesaving PAP in a timely fashion.

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 5:43 pm
by Janknitz
Here's Medicare's opinion on home sleep studies. https://www.cms.gov/medicare-coverage-d ... Id=227&ver

Since Medicare ends up paying for ongoing equipment, supplies, repairs, and physician care to treat OSA, it would seem that if HST's tended to consistently overscore sleep apnea where none exists, Medicare would be reluctant to cover them. AND, Medicare could slow the pipeline of people who get OSA diagnosis and treatment by refusing to accept HST's.

It appears to me that HST's are "good enough" for most, and hopefully the people who really would benefit from an attended in-lab PST will get them, either because the HST will flag something that needs further assessment or the failure to benefit from therapy (when the patient actually uses it) will warrant further assessment.

Medicare DOES cover in-lab, attended PST's without additional proof that is required rather than a HST, so it's not as if they are demanding everyone on Medicare have a HST just to save Medicare money (but some third party payors do).

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 5:59 pm
by Rubicon
Janknitz wrote:
Wed Jan 11, 2023 5:43 pm
Since Medicare ends up paying for ongoing equipment, supplies, repairs, and physician care to treat OSA, it would seem that if HST's tended to consistently overscore sleep apnea where none exists, Medicare would be reluctant to cover them. AND, Medicare could slow the pipeline of people who get OSA diagnosis and treatment by refusing to accept HST's.
Sure, they make up for the margin of error by using the 4% Rule and AHI criteria.

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 6:19 pm
by Centennial1
Janknitz wrote:
Wed Jan 11, 2023 4:02 pm
This is a summary. The Watch Pat produces a much more detailed report, he should ask for the full report. It might be more clear from that.
We called the sleep lab that gave the equipment and produced the report. They insisted that was the complete report.

Now, I had mentioned earlier that my wife had a WatchPat sleep study done at the same lab about six months ago. Her report was 7 pages and included flow graphs and the detain of when every event took place.

So apparently there are different WatchPat home studies, her study definitely had a nasal cannula, my brother’s did not.

Re: Help understanding Sleep study

Posted: Wed Jan 11, 2023 6:32 pm
by Centennial1
Rubicon wrote:
Wed Jan 11, 2023 4:13 pm
Yeah I'd look at the graphs, specifically the desats. They used the 4% rule, I think they're valid, but the mean nadir is only 92%.

Is the 82% real or artifact? If there's only like 1 significant desat out of the clear blue sky I'd be thinking about throwing it out.
Do you have any idea if the lab that did this study can expand the desaturation graph, to get a better look at the surrounding data, or even if the six second desat follows an “assumed” apnea.
A look at that might provide a better clue if that 82 was an artifact

Re: Help understanding Sleep study

Posted: Thu Jan 12, 2023 2:52 am
by Rubicon
Centennial1 wrote:
Wed Jan 11, 2023 6:19 pm
Now, I had mentioned earlier that my wife had a WatchPat sleep study done at the same lab about six months ago. Her report was 7 pages and included flow graphs and the detain of when every event took place.
Actually, you said your brother's wife:
Centennial1 wrote:
Tue Jan 10, 2023 10:30 pm
In truth, I am asking this question on behalf of my brother, who didn't want to create his own login and thread, and asked me to ask those questions about his new sleep study. ...

Incidentally, his wife's home sleep study, done about six months ago, actually did list the number of hypopneas, obstructions and clear airway events.
That is, unless now you are he.

Or I am he as you are he as you are me
And we are all together.

Goo goo g'joob.

Re: Help understanding Sleep study

Posted: Thu Jan 12, 2023 3:00 am
by Rubicon
robysue1 wrote:
Wed Jan 11, 2023 4:46 pm
In other words, what's the real benefit of a WatchPAT study? Other than the obvious that it's cheap and done in your own bed?
And a lot less stuff hooked up.

Re: Help understanding Sleep study

Posted: Thu Jan 12, 2023 3:13 am
by Rubicon
robysue1 wrote:
Wed Jan 11, 2023 4:46 pm
So does that mean that if a WatchPAT study indicates there may be OSA, then it's prudent to follow up with an in-lab sleep study?
That's not a question with a one-size-fits-all yes or no answer, but I had a Laboratory Itamar PAT Sensor for a while and ran it simultaneously with NPSG for comparison studies, and I tell ya, when it works, it works, and it's REALLY clever.

Re: Help understanding Sleep study

Posted: Thu Jan 12, 2023 7:17 am
by Centennial1
Rubicon wrote:
Thu Jan 12, 2023 2:52 am
Centennial1 wrote:
Wed Jan 11, 2023 6:19 pm
Now, I had mentioned earlier that my wife had a WatchPat sleep study done at the same lab about six months ago. Her report was 7 pages and included flow graphs and the detain of when every event took place.
Actually, you said your brother's wife:
Centennial1 wrote:
Tue Jan 10, 2023 10:30 pm
In truth, I am asking this question on behalf of my brother, who didn't want to create his own login and thread, and asked me to ask those questions about his new sleep study. ...

Incidentally, his wife's home sleep study, done about six months ago, actually did list the number of hypopneas, obstructions and clear airway events.
That is, unless now you are he.

Or I am he as you are he as you are me
And we are all together.

Goo goo g'joob.

Re: Help understanding Sleep study

Posted: Thu Jan 12, 2023 7:28 am
by Centennial1
My mistake in typing pronouns, is it really important?
Three people had sleep studies, two were WatchPat home studies.

Re: Help understanding Sleep study

Posted: Thu Jan 12, 2023 7:37 am
by Rubicon
Centennial1 wrote:
Thu Jan 12, 2023 7:28 am
My mistake in typing pronouns, is it really important?
There's really not a lot of things that are important when you think about it...