Interpretation Questions - My OSCAR Data

[ApneaQuestions]

Just an update on today's phone call with the Tech (not the Doctor)

1) I asked questions to get a feel for the "standard protocol" that he uses with the average patient
2) We then discussed my specific numbers
3) We then discussed me setting my own values

Your doctor and your technician may have different protocols.
In my case, The "standard" protocol goes something like this..

a) Supply the equipment with some defined settings
I didn't press him on whether they pay any attention to the split-night titration studies to guide the settings or simply a use a one-size-fits-all strategy.
In my case, the titration results wouldn't be much use because the studies were only semi-reliable due to poor sleep during the tests and due to being a mouth-breather who was titrated using a nose mask that I couldn't handle.
I am fairly certain I got default one-size-fits-all settings

b) Call the patient once every two or three weeks to see how they are getting on
Typically they look at the most recent weekly average AHI to see if it's looking reasonable or out of control.
They don't really look at much else.

c) After a few calls (maybe over 2 months) they hope to see stability in the numbers
In my case, this means seeing if the weekly average AHI is (say) below 5 or better
Because I mentioned CAs to him..  see if the percentage of CAs is coming down.  
I assume he'd check for treatment-emergent CAs for all patients.. but he didn't say so explicitly

d) Once stability is reached, they set you up for one night with an oximeter to make sure you are 90% or better

e) At that point they stop looking at any data and stop the phone calls
They rely on the patient to proactively call for help. Otherwise they assume the best and you go off their radar.


Then we talked about my personal data

a) As I predicted... He said the past week numbers were looking good
Weekly average was AHI=2.45  OAI=0.13  Hypopnea =0.77  CAI=1.56  RERA=0.1
b) As I predicted... He never even spotted the bad CA night (because it wasn't in the past 7 days)
c) He offered to order the oximeter today as part of the final "farewell" check this week.
d) I asked to delay that oximeter for a further week to give me time to make sure that the CAs are indeed gone (or going).
e) I explained that the numbers may look good but my sleep and fatigue are not.  Nevertheless I'll try to stick with it.

Then we talked about me altering my own settings

a) He appreciated that I was asking before tweaking
b) Their system does NOT have any automated algorithm that detects user-tweaks and forces them back to the "prescribed" settings by modem
c) He guaranteed that no-one would ever change my settings via modem without telling me first
d) He is fine with me changing settings because he knows I will be careful and use good reasoning
e) Once the "farewell" oximeter test has been performed and the final phone call made... he wouldn't even know that the settings have changed because they stop looking at the data
f) I didn't get any impression that there might be any intelligent algorithms monitoring for medically significant changes on an ongoing basis.  That surprised me because it seems easy to implement.

I thought this might be interesting to someone out there.  Your mileage may differ with your doctor/technician

[SarcasticDave94]

Some sounds typical for sleep doc, some not. Flying off radar probably means post compliance.

Keep at it. If there's something we can help with, ask away. We'll try to assist with applicable knowledge. Monitor the numbers especially CA and how you're feeling for therapy. Make Dr. Duck help if it applies.

[ApneaQuestions]

Yesterday I felt worse than I remember at any time in my life.  I think it is all caused by lack of quality-sleep getting used to the APAP.

The level of "fatigue" was not in the "severe jetlag" category, it was in the "I think I am in some danger here" category.
I don't have a tendency for histrionics nor for hypochondria.

I was also getting body pains  (outer muscle-type pain as opposed to inner-organ-type pain).
The pain was from the top rib on my left side, across the top of my rib cage to the right side.
It felt as if I had repeatedly hit myself with a clenched fist and bruised myself. Obviously I hadn't done that.
It didn't feel like intercostal muscles because it was above the rib-cage. The pain didn't increase with an intake of breath, it was just constant.

BTW I have R.A. (controlled) and my groin/hips started to hurt like a flare was imminent... but today that has gone too.
I went to the store and at one point I was struggling to put words together in a sentence without sounding drunk or drugged.

Last night I slipped the mask on for an hour but then took it off because I felt I MUST get some uninterrupted sleep by hook or by crook.

Today I'm back to the baseline perpeptual jetlag feeling and those pains are now gone.
It's hard to put some symptoms into words but that's the best I can come up with.

BTW I'm not whinging here... I'm just trying to be as descriptive as I can .

This is all a bit ironic because the previous night was a perfect 0.0  (Yes I know that doesn't necessarily mean anything in terms of sleep quality)

Today I have been paying attention to some RERA threads and one comment in particular from @sleeprider in this post
http://www.apneaboard.com/forums/Thread-...#pid321925

He said..
The big fluctuations in respiratory rate together with flow limitations is what RERA looks like (respiratory event related arousals).  The reason you don't feel rested in spite of very good AHI.

So I looked at my chart and rearranged the curves to bring the flow-limitations and resp-rate together.

Does this look to you like a "really bad" night even though the AHI is zero?
I am still new to the interpretations and have no idea how these curves look on a scale of 1 to 10.

You can tell I was struggling because of the big gaps taking the mask off then trying again then failing again.
Would any zoom areas help?

[ApneaQuestions]

Here's a zoom plot showing the non-rounded inhalation flow-rate and the corresponding Flow Limit and Resp Rate peaks.

I'm still new to interpretation but if I am understanding RERA correctly... these look like pretty bad breathing patterns.
Any comments/interpretations on this zoomed area?  Do you agree that it's bad?


I come from a signal processing background (Geophysics seismic analysis) which focuses on wiggle plots.
I am wondering if there are "hidden" utilities in OSCAR to perform waveform combinations and algebra?

I suspect that if I looked at the following combined waveform it might be a good way to predict arousal likelihood and give an estimate of "sleep quality".

NewCurve[i] =  ( FlowLimit[i] * RespRate[i] ) ** N    (Where N is a user-defined "enhancement factor" to exaggerate the y scale of the NewCurve)

[Gideon]

There is enough there that it should be addressed.  It will be difficult.

I had you initially set EPR = 0 and that cleared up a lot of Treatment-Emergent Central Apneas.  
To treat the Flow Limits and RERAs, even though they are not showing as events, we need to get you to tolerate a high EPR/PS (pressure support).
To start set EPR=1, that's not near enough, but it is a start.  

This could require a PS of around 8 which will require a BiLevel machine, but for you it will not be that simple.  Remember you had fairly high Centrals with EPR = 3.


Read this Wiki http://www.apneaboard.com/wiki/index.php...tral_Apnea

This form of Apnea occurs because of you blood CO2 level being too low.  This occurs because with CPR your AutoSet is too efficient and washes out too much CO2 from your blood.  This is why turning off EPR lowered your central Apnea.

Here is your dilemma, too much EPR means more Central apnea. You need more EPR to treat your flow limits and RERAs but this will cause more Central Apnea.

A possible solution is a technique in use by a couple of doctors and sleep clinics in the Boston area.  This is to increase the CO2 concentration in your blood by betting you to rebreathe a little bit of CO2. This is done by effectively moving the mask vent further away and is called EERS (Enhanced Expiratory Rebreathing Space) you can read about it here.
http://www.apneaboard.com/wiki/index.php...ace_(EERS)


For now we will work on slowly increasing your EPR.  

[ApneaQuestions]

...To treat the Flow Limits and RERAs, even though they are not showing as events...

Thanks (as always) for the feedback and suggestions and especially for the references.
I will step EPR up to 1 tonight and try again.

Do you know if the RERA events are reported by the device or are they computed arithmetically by the OSCAR software?
I'm wondering how bad a RERA needs to be in order for it to be reported and what is the basis for deciding that a RERA has occurred?
The zoomed plot looked fairly bad from my limited perspective... so I'm a bit confused why that waveform would register as zero RERAs

I'm hoping that I might be coming to the end of the acclimatization and the treatment-emergent CAs.
If that's true... I might start to do better as we step up the EPR.

[ApneaQuestions]

...To treat the Flow Limits and RERAs, even though they are not showing as events...

.......
I'm wondering how bad a RERA needs to be in order for it to be reported and what is the basis for deciding that a RERA has occurred?
The zoomed plot looked fairly bad from my limited perspective... so I'm a bit confused why that waveform would register as zero RERAs
........

To get more information about RERA-related "non events" I added a couple of user defined flags

#1 - triggered if Flow Limitation 80% for 10 seconds
#2 - triggered if Flow Limitation 80% for 5 seconds

These settings detect more RERA-like issues that are not severe enough to qualify as true detected "RERA event".
I still have not found a precise definition of what constitutes a "RERA event" in the Resmed world.

All plots going forward will show those user flags in the event graph but I didn't pollute the other graphs by turning them on there.

[ApneaQuestions]

Last night's data...

1) Summary shows continual lowering of CAs  (presumably acclimatizing and treatment-emergent CAs may be in the past) (?)
2) EPR was bumped up from 0 to 1
3) CAs tolerable on that setting
4) A single official RERA manifested (zoomed in on it just to see what I can see)
5) All data in the summary is for APAP machine except Nov 19-24 which was an ASV one week trial

Guessing next step will be to bump EPR to 2 or 3

Symptoms/Subjective:
Many full-conscious awakenings, still feeling "chronic jetlag" and "fogginess". Nothing as scary as the "diem horribilis" from 2 days ago.

Any thoughts?

[ApneaQuestions]

I also zoomed in on the CAs in case that is useful too.

11 seconds and 19 seconds

[Gideon]

Set your EPR = 2, likely 3 for tomorrow depending on what we see, especially with centrals.