Oscar/Air report questions

[Dormeo]

For several "max" values, the actual number used is the 99% value.

[Osiris357]

This is purely a guess on my part but I think the machine can sense a change in the flow when you inhale. A sudden lower flow tells the machine to increase pressure and in doing so also keeps track of how long and how much of a decrease in flow there is and marks it as a flow limitation on the FL chart. Again purely a guess.

[Gideon]

No CPAP or BiLevel, even ASV alters Pressure except algorithmically in response to events.
These machines all maintain pressure constant.
Physics, a sudden lower flow will for a brief increase in pressure before the CPAP (any of the above) can react by slowing the blower and restoring the currently set pressure.

The machine can sense a change in the flow as it contains both pressure and flow sensors.

[raylock1]

       
Good morning.  Time for an update and questions  

I seem to have solved most of the OA issues with the use of a snore collar.  I bought the "Eliminator" at Amazon.  It is pretty hard but surprisingly comfortable.  It only took one night to get used to it.  It dropped my OA's in half immediately.  So now I am looking at CA's and Hyponeas.  Most of my CA's occurred during two eight minute periods during the early morning.  I am attaching the Oscar for these two periods just to see if anything stands out.  I included the Time at Pressure line just because I am curious if it has any significance and not sure what it represents.  (The leak rate and snore lines are not shown, just for clarity since nothing showed up in them)
Ok, now a question.  Looking at the Medicare criteria for approving treatments, it seems that they lump Hyponeas with CA's rather than OA's.  Is this correct or have I misinterpreted the criteria?  If correct,  I wonder what the reasoning is?  Thanks again for the great help that is available here.

[Gideon]

Time at Pressure just says what pressure you spent how much time at. It has no meaning with regard to therapy.

Detail in the flow rate chart helps, set your y axis to +/- 70 and add a zero dotted line, the separator between inhale and exhale.
Seein your pressure may be of some help.
If you haven't I would try EPR=0

Please reference the medicare criteria you are referring to. I do know that at least as it pertains to central apnea medicare distinguishes between obstructive hypopnea and central hypopnea.

[raylock1]

Please reference the medicare criteria you are referring to.  I do know that at least as it pertains to central apnea medicare distinguishes between obstructive hypopnea and central hypopnea.

Here  is what I had read on the ResMed website      https://www.resmed.com/us/dam/documents/...elines.pdf

I think, however, I read it too quickly as they seem to reference both Obstructive Hyponeas AND Central Hyponeas.  I was looking at the definitions at the very bottom of the page which deal with the criteria for approval.  Eg. Central apenas plus central hyponeas must be more than 50% of the total apneas (for this particular machine).  I had not seen Hyponeas referred to before  as obstructive or central.  I wonder how they distinguish one from the other?

Sorry for the confusing question in the previous post.  BTW, I will reduce the EPR to 0 to see how that works.  Thanks for the suggestion.
Ray

[Gideon]

On Sleep tests, PSG, it is considered optional to split the classification of hypopneas between central and obstructive.  This is improving and we are seeing more tests that are noting central hypopneas.

It is an Obstructive Hypopnea if ANY of the following are present:

• Snoring during the event
  
• An increase in the flatting of the nasal pressure flow or PAP flow signal
  
• Paradoxical breathing
  

You can only call the event a Central Hypopnea 

• if NONE of the above is present.
  

We can tell by looking at a zoomed view of the flow rate chart.

[SarcasticDave94]

Try this AAST article to see if it helps: https://www.aastweb.org/blog/scoring-obs...e-criteria

Significant excerpt:

So how do I tell obstructive and central hypopneas apart?

It is an Obstructive Hypopnea if ANY of the following are present:

1. Snoring during the event
   
2. An increase in the flatting of the nasal pressure flow or PAP flow signal
   
3. Paradoxical breathing
   

You can only call the event a Central Hypopnea if NONE of the above is present.

That's it! With a bit of practice and observation, you can identify the difference between the two and find the correct device modality and pressure for your patient.

[raylock1]

   
This would seem to be central apneas.  I am not sure whether the flow rate shows flattening or not.  Seems to be the same all along.

[jaswilliams]

You flow line is fairly flat due to the scaling but it looks to me like both the CA’s and Hypopnoeas are centrally based and I would suggest that an ASV is in your future, but it is a game to get one, it will require further sleep studies to have worse numbers on a BiLevel and possibly an ST based machine before finally getting an ASV.


To follow this course you need to be a Squeeky wheel