Need help understanding Flow Restrictions in Oscar

[originofstyx]

Hello,

I am a thin, 22 y/o male UARS patient with an RDI of 11. My symptoms include heavy brain fog, fatigue, and exhaustion. I have a ResMed AirCurve 10 VAuto. I can get my AHI down to <1 but this only helps mildly with my symptoms. So what I'm trying to do is configure Oscar to show 5s flow restrictions.

A bit more context:
-I run EPAP 9-10 with PS 3-6 and that gets my AHI<1
-Anatomical risks include narrow/high-arched palate and recessed jaws
-I have the MSE appliance installed which has drastically improved my nasal airflow but I still have septum deviation and congestion caused from AR or NAR. 
-I am planning an MMA surgery in the Spring of 2022, and using the BiPAP more as a crutch to feel less like death until I get the surgery.
-I am planning a coaching session soon with Dr. Barry Krakow for BiPAP self-titration for UARS and flow limitations. 

I configured Oscar to show custom user flags, my first flag being 20% flow restriction for 5s, the second flag being 50% flow restriction for 5s. After configuring this, these were my results from last night:
37 FR20% events, and 52 FR50% events.

Can anybody help me in interpreting these flow restrictions in order to get more benefit from PAP therapy?

[Gideon]

Your RDI in this chart is 0.92, in other words you have resolved your RDI.

Question, what is your height and weight? and are you an athlete? I'd like to check your breathing stats.
Based on your Tidal Volume I'll guess your weight to be 110 lbs.

[originofstyx]

Your RDI in this chart is 0.92, in other words you have resolved your RDI.

Question, what is your height and weight? and are you an athlete?  I'd like to check your breathing stats.
Based on your Tidal Volume I'll guess your weight to be 110 lbs.

My AHI is 0.92. How are you getting 0.92 for my RDI? I was under the impression that Oscar was not able to read RDI because you would need a Polysomnography for that, so the best way to estimate RDI is by tracking flow limitations. 

If RDI=AHI+RERAs, then there would be no way to determine RDI by Oscar alone because neither Oscar nor the BiPAP is capable of detecting RERAs.

I am 5'9", about 120 lbs. I do a lot of cycling.

[Gideon]

OK, that explains the low values.

I didn't check your device type. But with a PS of 6 I wouldn't expect to find much. So I was looking for other anomalies.

Have you scanned your entire flow rate in detail to id arousals yet?

[originofstyx]

OK, that explains the low values.

I didn't check your device type.  But with a PS of 6 I wouldn't expect to find much. So I was looking for other anomalies.

Have you scanned your entire flow rate in detail to id arousals yet?

When I scan the flow rate, I'll get periods for a while where the breathing looks completely perfect, and have that nice sinusoidal flow rate shape. Other times, I get what looks like airway collapse, arousals, hypopnea, or flow limitations (flat tops instead or rounded/sinusoidal ones).

[Gideon]

I read 1 as normal, no issues
2 as awake until the last UF, could be arousal but this is post arousal.
3 as arousal since I see normal before and after
The above by themselves is not a problem. Thus you need an index of them.

What is the "Index" times per hour of these and similar. Sorry, but these need to be manually counted on any machine.

And why 6? I'm not against it, I frequently use a high PS myself, but why?

[S. Manz]

My AHI is 0.92. How are you getting 0.92 for my RDI? I was under the impression that Oscar was not able to read RDI because you would need a Polysomnography for that,


.

Oscar can calculate your RDI as your preferred index, instead of AHI...the average number of respiratory disturbances ,obstructive apneas, hypopneas,are of course picked up by your machine and OSCAR uses them for RDI calculations (How AHI and RDI are the same numbers and Oscar is not doing this the wrong way either), however, respiratory event–related arousals [RERAs] cannot be detected by your CPAP and require a different methodology.......The setting is found in the preferences.
Also judging by the conversation, it appears to me that the sooner you get your corrective surgery , the better.
In regards to Flow Limitations, I have also posted the same question several times, with a wide variety of confusing explanations.
So I hope your thread ends with better results.

[pholynyk]

I noticed this: results from last night: 37 FR20% events, and 52 FR50% events.
and I'd like you to check something for me. The last time I used the User Flags, it seemed to me that 20% for x seconds meant a reduction to 20%, not a 20% reduction. Of course the 50% reduction is the same as reduction to 50%.
I'm suspicious because if it was 20% reduction, there should be more of them than the 50% reduction...
It may be easier to check if you turn on the red line at zero - by right clicking on the y axis at the left end of the graph. You can also expand the graph scale by reducing the upper and lower bounds there as well.

[Geer1]

As Gideon mentioned 1 was normal breathing, 2 and 3 were arousal/awake breathing. In 2 and 3 there were 3 "50% flow restriction" flags and none of them were real (post arousal), so the question is how many of these flow restrictions are real and occurring before an arousal (therefore being a potential cause of the arousal)?

I believe we may have already talked about this previously but it is easy to go down what I call the PAP rabbit hole chasing and hoping you will find improvement. Your flow rate chart shows disturbances/arousals but it isn't clear that these are caused by breathing issues. Lots of things can affect sleep quality and in cases like this OSCAR data is of little use unless you can see obvious flow limited breaths and RERAs when reviewing the flow rate data manually. If you can see obvious RERAs then as Gideon mentioned you need to count them manually when comparing results at different settings because these machines are not capable of analyzing and flagging breathing issues to the level you are hoping.