patrickbrem - Settling in to an AC10 ASV from a S9VPAP

[patrickbrem]

My history with CPAP started in 2012 with a sleep study that found severe mixed APNEA  (60+ per hour) - resulting in me being put on a Resmed VPAP adapt.  I fluxuate about 5 - 10% lighter (weight loss) from that original study and at one point even lower resulting in a spike in events on ASV which led to a 2nd sleep study and being switched to CPAP Vauto mode.   For a while....  until I gained again still below my original weight - and switched back to ASV (now an AirCurve 10 ASV)

I provide that history - for context for my questions below.  I'm fairly close to the weight range where my Central events start to drop.  My AC10 is at about 35,000 hours and my insurance is going off the 2nd study and refusing to approve a new ASV for me.   I also have been wanting a 2nd "travel" CPAP - and given all these factors - I purchased a used Resmed S9 VPAP with 230 hours of use (for a $100!!).  

For some reason I thought the VPAP was the same as my ASV - but quickly realized my error.  I did my best to take an educated guess at a reasonable starting point - and settled on Min EPAP 5, Max IPAP 16, PS5 in VAUTO mode.  After a slew of CA events and a 7.7AHI the first night, I consulted the forum and ended up adjusting the Trigger to "Very High".   Voila!   .77 AHI.  

Below are two OSCAR charts - from my AirCurve10ASV and from my S9VPAP.   Although the AHI is great on the S9 - i have questions about if the data shows equally effective therapy and noticed big differences in Resp rate and tidal volume (higher on the S9!).   I also noticed that my ASV had a lot more leak rate and Hypopnea events than the S9.   

Does it look like i have the S9 dialed in?  Do the difference make sense - and do they indicate recommended tweaks to the s9 setup?

Resmed AirCurve10 ASV:
   

Resmed S9 VPAP in VAuto
   

Thank you for your help!  
-P

[Crimson Nape]

Hi patrickbrem! -

It appears you have found your sweet spot on the S9. Everything looks good. I would get a few day's data under your belt and if the pressure numbers stay in or near the same area as your posted image, I would drop your upper limit down. The reason is, so you won't get an excessive pressure change on a bad night or if you happen to have a chin tuck.

Good luck!

-- Red

[patrickbrem]

Thanks, Red!

I feel like I accidentally got things right and still don’t quite understand everything. I’ll get more data and see if the results hold, but will lower the max pressure down a bit. If my CA events hold at those levels does that indicate that VPAP is just fine for me even with my history of mixed APNEA? Does either profile look to be more optimal or are they both completely fine but slightly different?

Does the leak rate and HA events on the ASV indicate anything that needs to be adjusted? My AHI for the AirCurve is consistently between zero and one so I’m probably being a little obsessive ?. 

Does it make sense that the two types of treatment would yield a different respiratory rate?  I’ll see if more nights on the S9 show a consistent pattern. 

Thanks for the education! It’s nice to understand more about the nuances of the treatment. 
-P

[patrickbrem]

Per a previous thread, I have an AirCurve10 ASV for my prescribed machine.  It was dying and my fight with insurance drove me to pick up an S9 VPAP Auto. With the help of the board I "thought" I had it dialed in as a backup and travel CPAP.   Insurance finally relented and I have a new AC10-ASV - but I've still been using the S9 as my "sleep away" solution so that I could leave my main unit at home.

All was good.   AirCurve AHI typically <1 and S9 AHI usually about 3 - 4.   I travelled from home (Seattle) to Mexico City this week (elevation 7400 ft) and my AHI sky rocketed above 50/60.   Is there any data below that might explain what the heck happened and how I can avoid it?  Is there a known correlation with altitude (oxygen levels) and CA events and I have to use ASV for those destinations?

AirCurve ASV Baseline in Seattle (March 22)
   

S9 VPAP in Seattle (March 21)
   

S9 VPAP in Mexico City with crazy CA/AHI (Apr 9)
   

Thanks for the help!
-P

[Crimson Nape]

Since both threads deal with your therapy and the other provides some background, I'm going to merge them. A good title seems to be, "patrickbrem - Settling in to an AC10 ASV from a S9VPAP".

- Red

[stevew168]

That's some serious serious CA's in Mexico!

[patrickbrem]

That's some serious serious CA's in Mexico!

You're telling me!   My three days in Mexico City were:

Mon (8th): 79.37 AHI
Tue (9th):  55.75 AHI
Wed (10th): 67.37 AHI

I'm still curious if anyone has thoughts on what the S9 data shows (or doesn't show).  Is it just that my CA is severe / exacerbated by low oxygen at altitued and only my ASV will work??

Thanks for anyone who has thoughts looking at the data.

Also for reference - I used the S9 here last night in Seattle and my AHI was back to 3.7.

Thanks!
P

[SarcasticDave94]

One explanation, you need to get back on ASV at altitude, possibly the rest of the time too.

Central Apnea can be multiplied at higher elevation, just like this. The VAuto can be acceptable for you until it's not, again in situations like this.

[stevew168]

As usual, I agree with you. When you go to a higher altitude, you need to breathe deeper and faster. And just as importantly to staying conscious, you are purging CO2 that drives your brain to signal your abdominal muscles to cause lungs to breathe.

As a private pilot who flew over the Sierra Mountains once around 14,000 ft., I know this. (As a pilot, you must have AHI < 5).