Resp. rate in OSCAR

[naposnore65]

I notice that Resp Rate in OSCAR (which btw is not displayed by the Resmed software) is measured in the inspiration phase.
From my sleep measurements (attached) OSCAR showed quite a broad variety of rates (see the Resp. Rate graph). However, from the flow rate chart, it is clear that my true respiration rate (measured on expiration) does not change. What happens is that the inspiratory phase is very irregular in shape and brings a fake measurement of the rate. 
If this is common for all users to have a more regular expiration phase maybe it would be better to measure the rate on the expiratory phase.
by the way any idea of what kind of illness the weird shape in inspiration means?

[Gideon]

welcome to the forum.

It is hard to see at this scale but I don't see a normal non-flow limited breath in that entire sequence. What Illness
1. Respiratory Effort Related Arousal
2. Upper Airway Resistance Syndrome
or you can just call it
3. Flow Limitations

A trick on the flowrate chart is to insert a red line at zero. Right click in the chart name area and you can navigate to a number of feaTURES.
All of them say that you have resistance in your upper airway.
The fix, at least for the moment, is in your hands. The best treatment for this os Pressure Support (PS) or in your case EPR.
Set EPR = 3, fulltime then repost.

[SarcasticDave94]

I'd agree with some sort of flow limit existing, begin using EPR full-time at 3.

[naposnore65]

Ok I will try tonight
in the meantime, I realized that since the resp rate OSCAR measures is the frequency of inspirations, this automatically becomes a measure of breathing irregularities. 
On the other hand, it is interesting to correlate this with the tidal volume graph (related to the amplitude of breaths). 
They are almost perfectly correlated, I..e bad sleep pattern is both low amplitude and irregular inspiration patterns.
Quite interesting.
Attached the whole night plot. 
But the airsense works quite well I would say 
Indeed, I have also taken a measurement of Sp02 from another device and the desaturation never goes below 94%, except at 2:30 where one can see from airsense a major respiratory event where it goes down to 92% which is still acceptable.
Still, I don't feel good, rather stunned I would say. My sleep is quite bad.
Thanks for the nice work you guys are doing.

[Gideon]

You are not showing one of the most important charts, especially for you, Flow Limits. It is Flow Limits that are the primary driver of pressure in ResMed devices.

The cluster of RERAs suggests that you are having a positional apnea problem, frequently chin tucking, and that could explaining the isolated chart you started with as well. While it may be as simple as removing an "extra' pillow, read the soft cervical collar wiki, the link is in my signature. What do you think?

[naposnore65]

ok I set EPR=3

Everything changed:

a) the AHI quadruplicates! many CAs and OSAs that were not there without
b) Resp. rate and tidal volume MUCH more regular
c) shape of inspiration cycle MUCH more regular 

So goodies and some baddies.
All in all, increasing the AHI so much does look a good thing...

Could it simply be due to night-by-night variation?

[cathyf]

If you look over at the summary statistics on the left, it shows your Flow Limits spend 5% of the night at 0.24 or above. (The "max" is not labelled correctly for FLs -- your 0.53 is actually the 99th percentile for flow limits.) But anyway, those numbers are ugly high -- general accumulated wisdom around here is that you want that 95th percentile number to be 0.10 or below.

(In 6.5 years, my 95th %tile FL has been below 0.10 maybe 20-30 times *sigh* Probably because those nights I had insomnia and spent 3/4 of the night wide awake with the mask strapped on! *double sigh*)

[kappa]

OSCAR does not calculate the respiritory rate - it is calculated by the Redmed software in the machine and reported by OSCAR. It would appear in the initial trace that you may have something messing with the flow during the first half (potentially both in inspiration and expirations phases). This could be cardiogenic artifacts or something else (although the amplitude seems very high for a cardiogenic artifact).

[Geer1]

I have started to record video of my sleep semi regularly. During my rem sleep I have some strange breathing (everyone does to some level) that has some interesting and similar but not exactly the same type of breathing and it is caused by twitches of my diaphragm (or other nearby muscles).

In your case you are having this for extended periods of time at a regular frequency. I believe this is what is called asynchronous breathing, in short I believe your muscles are contracting in an irregular pattern causing this strange flow rate.

I see on google that it appears obstructive breathing may be a cause this and for example the flow to the right of your zoomed in example shows flow limitation and RERA's. Your recent example with EPR turned onto 3 started showing higher AHI but look at the difference in your flow rate and respiration rate graphs!!! Your asynchronous breathing was occurring roughly half the night in first example you posted and now it is pretty much gone (as is your flow limitation also significantly reduced)!

This is one of those cases where although your reported AHI is higher I believe you just greatly improved your sleep quality and are on the right track.

Your obstructive apneas appear to be real (a couple zoomed in screenshots would help confirm) in which case a higher minimum pressure may help (I would start with 10 then maybe bump up to 11).

Edit: Higher min pressure will most likely help stop these obstructive apneas. In your previous example average pressure was 13 cm with no EPR meaning your EPAP (low pressure that holds airway open) was 13 cm. In the most recent night your average pressure was only 10.5 cm with 3 cm EPR meaning EPAP was only 7.5 cm on average (almost half what it was previously). The higher EPAP before was stinting your airway open but you were still struggling to breath effectively. Now you are breathing more effectively but airway isn't being kept open because of lower EPAP.