OSCAR interpretation - how to eliminate these centrals?

[neostarsky97]

Hi all,

24M, non-alcoholic, no drugs or recreational user. Was diagnosed with 14.9 AHI OSA last year post my septoplasty/turbinoplasty. Have been trying to get into PAP therapy and trying my hand at CPAP. 

My initial diagnosis had a fair bit of centrals mixed with hypnoapneas. Report attached.

I am currently using a VAuto - in CPAP mode because the S/VAuto mode was a bit over my head to understand initially but kept it as a safety so that I could switch if this current mode didn't work. 

Had been a long time lurker of /r/SleepApnea and was recommended here for OSCAR interpretation. Please help me understand my previous night's usage where I had a few centrals, and where I can tweak it to reduce that amount.

First image: Zoomed in on central event 10 minute interval
Second image: Entire night analysis - please ignore the first half hour - I was awake and on a call.
Third image: sleep study report

[staceyburke]

Welcome to the board.  Please put up the entire night with events not zoomed in.  If someone needs to see a zoomed in portion they will ask.  

The vauto is a great machine that I also use.  but using it as a cpap is defeating what it can do.  If you are ok with it I would like to see one night with the following setting.

ps 4
min 4
max 18
trigger set to high

That gives you an inhale of 8 an exhale of 4 and the trigger set at high has been found to lessen Centrals.

[neostarsky97]

Thanks for your reply.

The full night analysis is also posted, please check the second image.

I will try it out with the settings you have provided. But just to be clear, this is on VAuto mode correct? 
The trigger as I understand has Ti Max and Ti Min along with some other parameters. Could you tell me what 'high trigger' would correspond to on these params?

[Gideon]

TI min and Max are a pair of different parameters designed to allow alter the durations of the breath. These are different than the Trigger and "Cycle" parameters which affect the amount of signal to transition to Inhale (Trigger) or Exhale (Cycle). Detailed explanations of all four are contained in the clinical manual you can obtain in the CPAP manuals link in the black banner above.

[Dormeo]

Yes, you should shift to VAuto mode.

With your centrals, I'd recommend not increasing pressure support to 4 right away. Instead, you could try staying at 2 and using the high trigger to see how that goes.

In CPAP mode, you use what is called EPR. EPR drops your pressure on exhale by 1, 2, or 3. In VAuto mode, you'll be using what is called pressure support, which increases your pressure as you inhale by the amount you set. In both cases, there's a pressure difference between inhalation and exhalation, but the way to use the settings will be different.

For that reason, when you're in VAuto mode and using pressure support, mimicking your current CPAP settings would mean setting your minimum EPAP at 4.4 and pressure support at 2, with a maximum IPAP of 6.4.

tracyburke has recommend increasing your maximum IPAP to 18. I'm not sure why; maybe he could clarify. I'd be inclined to start your experimentation by mimicking your current settings and simply using a high trigger to see how that goes.

[neostarsky97]

Thankyou to the community members who have replied to this post and guided me. 

I had switched to the VAuto mode and tried a couple of nights. I'm glad to say I had my first night of 7 hours with 1.26 AHI ! 

I had a bit of aerophagia today morning, stomach hurts a little but I guess I should reduce my max IPAP a notch. 

If there's anything I may need to adjust more, please have a look. Posting my analysis.

Here's hoping I sleep for longer consistently! 

[Dormeo]

So glad you had a better night! Was this with the high trigger? You could bring your max IPAP down a little to see whether it helps with aerophagia. Sometimes a small difference will do the trick.

[neostarsky97]

So glad you had a better night!  Was this with the high trigger?  You could bring your max IPAP down a little to see whether it helps with aerophagia. Sometimes a small difference will do the trick.

Yes it was the high trigger. I had actually brought down my max IPAP a little - I don't have aerophagia anymore but now what's happening is I seem to be waking up after 5-6 hours of usage...Attaching OSCAR for the most recent night. Had some hypoapnea events right at the end before waking up. Any more tweaking I may need to do?

[Dormeo]

I recommend that you stick with these settings for at least a week before you consider any further changes. It’s normal for sleep to be different from one night to the next, so let’s see what the general trend looks like.

[neostarsky97]

Thanks Dormeo. Will update back on the thread after a week or so.