Tweaking ASV

[ahuman]

I switched to ASV and am not sure how to start adjusting. How should I start dialing this in and what am I looking for in these traces as some appear different to the CPAP/BiPap. Some of the flow rate has flat tops so that seems to indicate that there is tweaking to be done. The flow is also somewhat inconsistent breath to breath.

https://lh3.googleusercontent.com/drive-...1600-rw-v1

[mlmollenkamp]

ASV is a completely different animal than APAP.  Not much relates.  I made the switch about a month ago and am doing well now.  It would help to know more.  

Are you starting with settings that were derived from a sleep study? or are you starting with default settings?  
What machine do you have?  
Do you have a sleep doctor?  
Is there a specific problem you are trying to address?  

Answer these and send an OSCAR printout, there are people here who can help.

[SarcasticDave94]

I have used an ASV in the past, and should be able to help make therapy better suited. We do need to get you to provide an OSCAR chart. It's free and safe.

You'll need an SD card in the ASV before sleeping to collect detailed data.

Also, what are your current ASV settings? Which seemed to help the most?

While we wait on OSCAR data, here's the ResMed ASV Titration guide to assist.

   

[ahuman]

What made you stop using ASV? 

I'm using an Airsense 10 ASV in ASVAuto. Despite a sleep study at a an academic medical center, they did not titrate me. I am starting with the setting the sleep doctor gave the DME. I linked to a night from Oscar. When on bilevel, I was at about EPAPmin 9, IPAPmax 14, PS 4. 

I looked at the Resmed ASV mode titration protocol, I'm not sure how to check that obstructive events are eliminated. The machine does not flag much for me so it requires a manual review. 

When looking in detail, I can see that some events are happening and causing the machine to adjust. For the ASVAuto protocol, I'm not hitting EPAPmax so that instruction does not add much. Should I start with the non-ASVAuto protocol and increase EPAPmin by 1 and then check for unflagged events? Or do I do something more complicated such as EPAPmin plus PSmin is at least Median pressure in statistics?

I'm initially trying to find a balance where the machine has enough range but also does not need to adjust as much as that can disrupt sleep. Once I can get that a bit better, then I can try to refine it more.

[SarcasticDave94]

I also have COPD level GOLD 3, which is listed as having ASV contraindicated against using. COPD and ASV didn't play well together for me.

I'd rather you use the New Attachment button to attach the OSCAR charts to your posts. See my signature link for attaching OSCAR charts.

Anyway, you may want to reduce EPAP Max by 5 down to 10. Then take that 5 and add it back onto PS Max. Give this a try, mainly for comfort. That AHI was zero, and you can't get better in numbers. So any edits need be focusing on comfort.

[ahuman]

Can you explain this suggestion in more detail? Limit EPAPmax to manage upper limit of exhale resistance for comfort? What is the purpose of increasing PSmax - to provide ample IPAP runway in case it is needed? I'm not sure how unpleasant it is to be hit with 25 cm but perhaps on inhale it would not be terrible.

[SarcasticDave94]

You EPAP Max didn't get to 10 with current settings, and I'd thought to keep it that way. Meant to be kept out of the way some so you'll get PS working a bit sooner. With the ASV, PS blips for inhale will always be a shorter duration than EPAP which is what the pressure is based off of. It'll only hit Max PS when required.

[ahuman]

I'm still dialing things in so here is a whole night and some zoomed sections where I'm not sure what is going on or how to address each one. I put labeled each with an image number to try to make it easier to reference with any ideas. Thanks for any suggestions.

Image 1:


Image 2:


Image 3:


Image 4:


Image 5:

[SarcasticDave94]

Still zero AHI, so that's the same. Perfectly fine that way. Is it comfortable with this setup? If so I'm not seeing anything to edit.

[ahuman]

AHI is not always zero but usually low so it's not much use for me to consider. I'm trying to optimize the flow rate as much as possible. For example, possibly I should bump PSmin more to address flat tops. I also sometimes get events that are not flagging suggesting that EPAPmin should possibly move up a little so the machine is not stuck trying to react. I'm trying to better understand what is going on in the zoomed in sections to assess whether I can improve each pattern or it might be positional or something like that where there is not as much I can do in terms of machine settings.

As for comfort, hard to say as ASV is different feeling than BiPAP. Possibly there could be more flow at times which is another reason I'm going to try bumping EPAPmin.