Appreciate help adjusting settings (UARS)

[cmcphee]

@mper6794 I'll definitely make those graphs. Couple questions:

- What numbers are you using for your X axis (CAs)? Are you graphing CAs/hour, per night or another unit?
- You mention "CAs have to be recounted by yourself, no Resmed report!" - what durations (or other characteristics) am I looking for? general disturbances?
- Any graphs that I should make from when I was on the AirSense for three weeks? I've only been on the AirCurve for a few nights.


@bonjour I will post screenshots from last night w/ reduced PS shortly - long story short, way fewer centrals and slept for almost 6 hours.

[Gideon]

sounds like a success. let's see is another adjustment is needed.

[slowriter]

@mper6794 I'll definitely make those graphs. Couple questions:

- What numbers are you using for your X axis (CAs)? Are you graphing CAs/hour, per night or another unit?
- You mention "CAs have to be recounted by yourself, no Resmed report!" - what durations (or other characteristics) am I looking for? general disturbances?
- Any graphs that I should make from when I was on the AirSense for three weeks? I've only been on the AirCurve for a few nights.

mpers6794 and alexp are saying that most of the CAs reported by these machines aren't real centrals, and that you can tell by looking at the flow rate graph in relation to tidal volume. 

I don't 100% understand it, but alexp lays it out here. 

I would like to see wider discussion of this, and see it on the wiki in time.

In my case, I just don't believe what the machine is telling me on those CAs (my titration study turned up a single real CA the entire night); seems more a rough measure of how well I slept.

Not saying it can't be different in your case, but maybe take a close look at the TV per alexp?

[slowriter]

PS - I think part of the problem is the unfortunate fact that what Resmed means by CA is much more vague a thing than Central Apnea. Wish they found a different acronym.

[mper6794]

@mper6794 I'll definitely make those graphs. Couple questions:

- What numbers are you using for your X axis (CAs)? Are you graphing CAs/hour,......yes, CA's/hr....and the median for RR.
- You mention "CAs have to be recounted by yourself, no Resmed report!" - actually, I just recounted flagged CA's, but only those ones not associated with arousal/awakenings/wake-ups (either due to any kind of air flow reduction - AFR - or PLM's). This is the trick! knowing how to spot ar/aw/wk; pratice will tell you how to do it (tidal volume, flow rate, and leaks are all the information you need). Later on, I will try to share examples on how to spot and discriminate ar/aw/wk due to AFR or PLM's. 

- Any graphs that I should make from when I was on the AirSense for three weeks? I've only been on the AirCurve for a few nights......well, I think you coud use any pressure support (EPR,,,),  yet, in my case I have used just BPAP values.  It may works....until you get more PS from you Bilevel. 


@bonjour I will post screenshots from last night w/ reduced PS shortly - long story short, way fewer centrals and slept for almost 6 hours.

[cmcphee]

Ok thanks mper6794, let me know when you write something up about how to identify awakenings. would love to apply to previous data too.

Quick question for everyone, at the risk of sounding like an idiot. Could you please help correct or confirm my understanding of pressure settings on the two machines I've tried:

• AutoSet Air Sense for Her with Min 9, Max 12 and EPR 3 would result in pressure ranges of 9/6 - 12/9?
  
• AirCurve vAuto with EPAP 5 , IPAP 12 and PS 4 would result in pressure ranges of 9/5 - 12/8?
  

In other words, EPR on AutoSet decreases a min and max, whereas PS on AirCurve vAuto increases the EPAP and decreases the IPAP?

[slowriter]

... In other words, EPR on AutoSet decreases a min and max, whereas PS on AirCurve vAuto increases the EPAP and decreases the IPAP?

Even simpler than that. Effectively:

EPR decreases EPAP (hence Expiratory Pressure Relief), and PS increases IPAP (the "support" is on inhale).

It's easier to understand it if you assume fixed pressure.

Also, the vuto display shows what it's doing with PS on the sleep report, while it's running.

[Gideon]

Ok thanks mper6794, let me know when you write something up about how to identify awakenings. would love to apply to previous data too.

Quick question for everyone, at the risk of sounding like an idiot. Could you please help correct or confirm my understanding of pressure settings on the two machines I've tried:

• AutoSet Air Sense for Her with Min 9, Max 12 and EPR 3 would result in pressure ranges of 9/6 - 12/9? correct
  
• AirCurve vAuto with min EPAP 5 , max IPAP 12 and PS 4 would result in pressure ranges of 9/5 - 12/8? in VAuto mode
  

In other words, EPR on AutoSet decreases a min and max,(pressure will be pressure - EPR down to machine min of 4.) whereas PS on AirCurve vAuto increases the EPAP and decreases the IPAP?  no there is no decrease.  IPAP = EPAP + PS.

red is comments by bonjour

[alexp]

@mper6794 I'll definitely make those graphs. Couple questions:

- What numbers are you using for your X axis (CAs)? Are you graphing CAs/hour, per night or another unit?
- You mention "CAs have to be recounted by yourself, no Resmed report!" - what durations (or other characteristics) am I looking for? general disturbances?
- Any graphs that I should make from when I was on the AirSense for three weeks? I've only been on the AirCurve for a few nights.

mpers6794 and alexp are saying that most of the CAs reported by these machines aren't real centrals, and that you can tell by looking at the flow rate graph in relation to tidal volume. 

I don't 100% understand it, but alexp lays it out here. 

I would like to see wider discussion of this, and see it on the wiki in time.

In my case, I just don't believe what the machine is telling me on those CAs (my titration study turned up a single real CA the entire night); seems more a rough measure of how well I slept.

Not saying it can't be different in your case, but maybe take a close look at the TV per alexp?

The idea is that if you draw more air in your lungs, your desire to breath is reduced for a little while. Try it while awake, take a couple of very deep breaths and you'll see that you don't need to breath for some time. It's perfectly normal. That's not a central apnea. The same thing happen when you sigh during your sleep. In fact, if I wear the mask while awake and turn on the machine, the machine will report some central apneas. Therefore that's mean an arousal during my sleep might be reported as a CA as well. 

Without EEG, there is no way to distinguish an arousal from a CA except scoring the events manually and even then there is no certainty. It's important to understand that people move, sigh or wake up during their sleep and the machine can flag these events as CA. REM breathing is also quite irregular and can look like CA especially when you are dreaming.

A real central apnea happens without a big increase in flow rate or tidal volume. You are breathing normally when all the sudden you stop for no apparent reason.

In my case, when I increase the PS too quickly, I get an increase in CA events. Most of these events usually follow a series of deep breaths. I think it's my body just trying to figure how to breath with all this air coming in. It's usually goes away after a week or two. Might not be the same for everyone though.

I think in your case you should definitely lower your PS to 3 or even lower and rise it gradually in a week or two if you are still experiencing some flow limitations.

[cmcphee]

Ok thanks @alexp for the thoughtful explanation. I can definitely count some of the CAs out from your description. However, I think I'm still seeing a lot more two nights ago than normal. Am I interpreting the attached graph correctly that these are CAs because my respiratory rate and tidal volume are steady?