[CPAP] AHI 6-10 with mostly clear airway events?

[sleepo]

Hi everyone,

This forum has been a huge help for me to get started using CPAP therapy, and it's already made a big difference for me. I've been using my CPAP for about 6 weeks, and I'm hoping I could get some advice about optimizing my therapy.

I'm typically getting an AHI of 6-10 or so, and most of it is from central airway events. I'm wondering if this could be treatment-emergent CSA, or maybe it reflects actual central sleep apnea and I might need to try an ASV? I've attached two recent nights of OSCAR data, plus my original home sleep study with my diagnosis.

Here's what I'm currently using:
- Machine: Resmed Airsense 11
- Mask: Resmed P30i (nasal pillows with tube connection on top of head)
- Settings:

• Mode: APAP
  
• Pressure Min: 5.00 cmH2O
  
• Pressure Max: 20.00 cmH2O
  
• Antibacterial Filter: No
  
• Climate Control: Manual
  
• EPR: Off
  
• Humidifier Status: On
  
• Humidity Level: 1
  
• Mask: Pillows
  
• Patient View: Off
  
• Ramp: Off
  
• Response: Standard
  
• Smart Start: Off
  
• Temperature: 23 ºC
  
• Temperature Enable: On
  

If anyone has any suggestions for me, I would greatly appreciate it! Hoping to get my AHI even lower!

[jdougc]

Welcome to the forum,
We need to see the device settings, are you using F12 for an Oscar screen capture?

Your minimum pressure is too low for an adult, you need at least 7 cm of pressure. 
Raising the minimum may also help stop some obstructive events on your hypopneas.
is your ramp on? Make sure to raise the ramp pressure to 7cm also.

Your flow limits are too high, you need EPR to fight that, use at least a setting of  EPR of 2.
If you feel airstarved with EP on, don't turn it off, but raise your minimum to 8cm

[SarcasticDave94]

Welcome to Apnea Board,

Thanks for supplying the sleep study. OK, you have an issue with Central Apnea on the test. 290 CA under the line pAHIc 3%, total events 596. Your CA of 290 is just under half the total events. Regardless of reason, you have a sensitivity to Central Apnea.

So, currently you're not doing too bad with the AutoSet, but not great. So look at your summary history involving CA events. They will very likely be up, down, absent then return, with no settings changed. This is the typical CA trait called consistently inconsistent.

Do your best to make CPAP, AutoSet work, but when you're done and ready to get a better machine, you'll probably have to try the bilevel VAuto next, for insurance coverage purposes. Note that it may be worse for you than CPAP, because those CA on the test are evidence you'll eventually want ASV, and the standard bilevel is iffy for CA. The VAuto has the Trigger setting that helps avoid CA for some.

Discuss with your doctor about that high CA count on the test result. Ask them when they plan to address and treat them. Right now, they're only attempting to treat half your total test events, and it's very likely not nearly good enough.

CPAP and bilevel that doesn't have a backup breath rate like the ASV cannot treat CA. You can try to avoid some though. And there's a big difference between treating them and avoiding.

[sleepo]

Really appreciate the advice from both of you!

I've attached another OSCAR daily screenshot with the left panel zoomed out so you can see the device settings, plus the overview screenshot of the last couple weeks to show what my AHI has been each day.

I met with my pulmonologist last week and he said that he thought my AHI was totally fine and to just continue with how I'm currently doing things. He thought that the central events were likely treatment-emergent CSA and said that it could be a few months before my brain adapts to using the CPAP.

I had turned off EPR after reading some other comments on this forum that suggested it might contribute to central events, but I can definitely experiment with turning EPR back on. I'm not too familiar with looking at flow limits - what should I be looking at there to see if things are going well?

Thanks again, everyone, I appreciate it so much!

[jdougc]

SarcasticDave94, is right that CPAP and bilevel that doesn't have a backup breath rate like the ASV cannot treat CA.

Your flow limits are too high and driving up your pressure, you need EPR to fight that, use at least a setting of  EPR of 2.
If you lower your pressure swings, your CAs may lower.
Consider a tight pressure range of 8-10 cm for a few nights.

Lose the few weeks of AHI data, nothing useful there.

[SarcasticDave94]

They can't be treatment emergent CA, so this pulmonologist is not correct, because the CA were on the test that was without CPAP. That was supposed to be a diagnostic test.

Correct, lower pressure variable may help.

[sleepo]

Gotcha, that makes sense.

Sounds like I should try out a smaller pressure range with EPR on. 

And also ask my doctor about using another type of machine to treat the central events! I'm guessing he'll tell me that it's not worth it if my AHI is already this low, but I think it's worth looking into.

[CLCCW]

I just went down a very similar path as yours. Tested with Centrals and OAs, LOTS of Centrals. They started me on AirSense 11 as APAP, with pretty minimal range (5-8 I think). My OA was pretty non-existent, then, but I had crops of many CAs and AHI would wax and wane from like 7 to 15 or so. All over the map. They switched me to CPAP at 9 and that helped a bit, but CAs were continuing. The goal is to be under 5 AHI, and minimize the hypopneas, too.

I lobbied hard for an AirCurve 11 ASV which was like pulling teeth but I got it. First night, my AHI was 1. something, and a smattering of hypopneas. It works.

My centrals are not due to cardiac stuff (tested), nor opioid or other narcotic use (don't use), nor any neurological issue I am aware of. My brain just does not communicate to breathe appropriately when sleeping, apparently. I also live at over 5,000 ft and some of us at that altitude even for a long time, have this situation. Or, it is totally ideopathic.

I just wanted to respond to say it seems they want to keep you on CPAP (claiming insurance won't go for ASV) but we made it happen (I had lots of coaching from SleepRider and Sarcastic Dave). Some times "good enough" can be made better.

Try what you need, but begin reading about the efficacy of ASV for those like us. Good luck with your new settings!

[sleepo]

That is so helpful to hear how the ASV worked for you! I really appreciate you talking the time to describe your journey - it really does sound similar to my situation.

I will definitely look into ASVs and see if I can start the conversation with my doctor. Thanks so much, everyone!

[sleepo]

Hi everyone, just wanted to say thank you again and ask for some further advice.

I took your suggestions and tried a pressure range of 7-10 with EPR 2 for a few nights, and then tried 8-10 with EPR 3. Both seemed to not change much from my results under previous settings (still getting AHIs of 5-10 with mostly central events). I've attached OSCAR screenshots for one night with each settings.

Is there anything you might suggest trying with my CPAP that could help, or do you think this is really a sign that ASV is the way to go?

Thanks again, everyone!