VAUTO not reacting to OA's

[yrnkrn]

One thing that ResMed said was to try Supplier #1 for a new machine. Nice to know.

I'm considering switching to bilevel and really interested in the bottom line here, if you try AirCurve from another supplier please update if it works differently than the ones you had.

[yrnkrn]

Crimson Nape and Dave,
                                     The VAUTO saw the OA and should have responded. The mask setting wouldn't have made a difference.

PaytonA experience here was the wrong mask type was causing his S9 VPAP Auto to behave differently, "As soon as I masked up and turned the machine on, I could tell that something was off a little. the transitions from EPAP to IPAP and vice versa were much more abrupt and forceful- made my mask do pushups on my face. As soon as I corrected the mask setting, I got my nice, smooth transitions back."

palerider thinks the mask type is probably used for more than the leak rate calculation, if at all, since "another wrench thrown into that is that in the resmed mask category, you'll find that some masks of the same type have bigger leakage variations within that same type than the variation with other types of masks."

This makes sense given the larger deadspace of FFM vs Pillows which the machine has to take into account.

With IPAP being quite high at 23cm,  and the mask behaviour mismatches the machine expectation, maybe some failsafe internal event was triggered, disabling further pressure increases. Imagine some "FOT result unreliable" event, do nothing now.

Also interesting all(most?) OAs are leakier then other times.

Could you fully zoom in on some un-leaky OA ?

[Walla Walla]

Update on my saga with the return. I had to return 2 machines as noted before at a cost of $167. The machine cost when ordered $1128. So I laid out $1295 to date.

I received a letter from Amazon stating they have confirmation from ResMed that the machine I returned has no issues. So they're only going to refund me 50% of the purchase price minus $11 for their shipping.

I ended losing $742.00 without anything to show for it. That's your Amazon A to Z refund policy in action.

Buyer Beware.

[Sleeprider]

So what are you going to do with the second machine? I can't explain why it doesn't up-shift that last 2-cm of pressure automatically, but is it really a therapeutic problem? Why not just set 25/22 and have at it?

[Walla Walla]

Sleeprider, I sent the second machine back. Found out I can stop shipment through UPS and have it returned. So at least I'll end up with a non auto EPAP and a Auto IPAP ????   It may seem like only a few pressure points but my DreamStation Auto Bipap seems to work just fine at the higher pressures. So I expected the same from ResMed. Now I know not to depend on Amazon's return policy.

[yrnkrn]

I'm not really sure at this point the machine is faulty. ResMed algorithms are very different than Respironics.

At least now you can learn more, SleepRider suggestion to start with lower min EPAP to see if VAUTO stops responding at some pressure point is good idea.
Could you try minEPAP=16cm PS=3 so that starting point is 19cm which is < 20cm?

I don't know if such limit actually exists in VAuto but is not unheard of in ResMeds.
The For Her algorithm stops at 12cm and pre-S9 machines stopped at 10cm.

Another possibility is that it does not respond due to low flow limitations.
Look at 02:00-02:20 there are tons of OAs but no flow limitations. Isn't this odd? 
Could you zoom on this area to maximum zoom to see individual breaths flow?

[Walla Walla]

I'm not really sure at this point the machine is faulty. ResMed algorithms are very different than Respironics.

At least now you can learn more, SleepRider suggestion to start with lower min EPAP to see if VAUTO stops responding at some pressure point is good idea.
Could you try minEPAP=16cm PS=3 so that starting point is 19cm which is < 20cm?

I don't know if such limit actually exists in VAuto but is not unheard of in ResMeds.
The For Her algorithm stops at 12cm and pre-S9 machines stopped at 10cm.

Another possibility is that it does not respond due to low flow limitations.
Look at 02:00-02:20 there are tons of OAs but no flow limitations. Isn't this odd? 
Could you zoom on this area to maximum zoom to see individual breaths flow?

I don't know where you got the information about the ResMed algorithms being limited on the models you just mentioned but it's not correct.

Also EPAP doesn't respond to flow limitations IPAP does.

As far as testing the machine I'll probably do that when I finally get it back.

[yrnkrn]

The For Her algorithm stops at 12cm and pre-S9 machines stopped at 10cm.

I don't know where you got the information about the ResMed algorithms being limited on the models you just mentioned but it's not correct.

I meant this in context of the thread topic, the pressure limit of the algorithms when responding to OA. 
Sorry if this wasn't clear enough. References -

For Her algorithm
The maximum pressure due to a closed airway apnea is 12 cm H2O. The therapy pressure still increases above 12 cm H2O if it is driven by either continued snoring or flow limitation. This reduces the likelihood of reaching high pressures over short periods.

Resmed autoset s9 vs. s8 events
S8 autoset does not increase pressure above 10 cm H2O when an apnea detected nor respond to hypopnea to avoid falsely responding to central hypopnea.

[Walla Walla]

I stand corrected on the Air Sense for her. I don't think that applies to the VAUTO though. If it was limited than the IPAP wouldn't have increased.

[Walla Walla]

Here is a chart with the pressure set at 17cm. It appears to be responding to OA's. So is there a limit built in? I have no idea.
I know my DreamStation reacts to OA's above 20cm. I also know my DreamStation shows lower leak rates starting off. What it means I have no idea. I have noticed some Resmed machines posted on here starting off higher on the leaks too. Not all but some. At this point I'll put the VAUTO in it's bag and use it for a backup. It still can still blow air and that's the main thing.
[url=https://imgur.com/Ygzqqtz][/url]