'inhale' time / other confusion on resmed vpap auto 25

[johnspartanII]

Indeed, I have recently seen my sleep doc, been trying to successfully use xpap for a long time now (over a year). My apnea is considered 'mild to moderate', so doc is recommending I might try a dental appliance, but as I keep feeling worse and worse, and everyone says that xPap beats the dental appliance even if it works, I'm trying to not give up on the machine. This is the 3rd? xpap machine I've had, and it seems to have a lot of features, but I have not tried as hard to really isolate the problem that might be keeping me from sleeping with it much - until now. Probably because I'm reaching the 'walking dead' stage.

Despite doing everything you guys typically suggest, I have still yet to successfully sleep for more than an hour? maybe? despite really not feeling claustrophobic, with the exception of maybe two or three times where I had severe aerophagia kick in - and I can't afford aerophagia since I've got terrible stomach and gi issues already. I'm using the full Quattro face mask which fits pretty nicely, and I don't get leaks as long as I'm not too stubbly at bedtime. But if I can get sleeping regularly with the thing, I'll deal with the aerophagia somehow. I hope.

Anyway, at the doc's yesterday, since I thought I perceived not getting enough inhalation air in general, they increased the overall pressure range. Now that they have, though, I can definitely tell that the thing that has been bothering me seems to be - the pap is deciding I am done inhaling before I actually am, vs. the actual pressure. I called the doc's office today but it might be a few days before they get back to me.

So my questions:

1. I think I've determined this has to do with the Ti min & Ti max settings, but I'm scratching my head determining exactly how to adjust this so it would benefit me. Likewise I see there's some other 'sensitivity' type settings, but I'm unsure which to look at.

2. I know that my auto 25 in auto mode (how they've been having me try using it) appears to have a range of max ipap and min epap, plus the pressure support number. I get the idea of this, although how it knows where to actually START the pressure level - when you first turn it on - vs. the "max" & "min" settings, I do not understand.

I've seen several threads around here talking about differences between 'auto' vs. 'bipap', so I did search! but I'm still unclear.

Thank you so much for your help, cpap-ers.

[fiberfan]

I have an S9 VPAP Auto, not the VPAP auto 25 you have but the settings I modified on the S9 have the same or similar descriptions in the VPAP Auto 25 and S9 VPAP Auto provider manuals.

Now that they have, though, I can definitely tell that the thing that has been bothering me seems to be - the pap is deciding I am done inhaling before I actually am, vs. the actual pressure.

I had this problem with the default settings on my S9 VPAP Auto. I increased the Ti Max until the machine didn't switch to epap until I had stopped inhaling. The S9's display let me see the current pressure so I could see it switch too early. I may have changed the Ti Min after reading the provider manual.

Likewise I see there's some other 'sensitivity' type settings, but I'm unsure which to look at.

After reading the provider manual, my understanding is that trigger sensitivity impacts how quickly the machine switches from epap to ipap while the cycle sensitivity impacts how quickly the machine switches from ipap to epap.

2. I know that my auto 25 in auto mode (how they've been having me try using it) appears to have a range of max ipap and min epap, plus the pressure support number. I get the idea of this, although how it knows where to actually START the pressure level - when you first turn it on - vs. the "max" & "min" settings, I do not understand.

I haven't learned about ramp settings since I don't use them but without ramp my S9 will start with epap and min epap and ipap and min epap + pressure support. When the machine sees a flow limitation it raises both epap and ipap with ipap staying at epap + pressure support. Max ipap is the highest ipap will ever go so the max epap is max ipap - pressure support.

[dsm]

Just offering a word of caution. It can be tricky playing without those settings with expert guidance such as from your R/T.

Altering those timings adversely can impact your respiration rate & tidal volumes - these when set wrong can in turn impact your blood CO2 levels.
The best way to play with those settings is with an R/T & particularly if the R/T can monitor the effects on your respiration & blood CO2 levels possibly with a oxi-capnograph monitor (does both SpO2 levels and EtCO2 (end tidal CO2) levels).

Good luck

DSM

[johnspartanII]

DSM - I hear you. This doc I just saw, he hasn't had me titrated or done a study himself yet... i'd previously seen two other docs, and the settings on my machine were from the previous doc. My understanding is that they have increased the overall pressure (as per the #'s I can see in the machine not to mention just turning it on) - but it feels almost exactly the same as before, except, well, with more pressure being blown at me.

I figured I'd ask though, because
a.while I do find the machine complicated and would prefer that the doc's office helps me adjust it just how i'd like, their response time is not exactly quick. They don't know me very well there yet, though, so that could change.
b. I just like knowing how the heck a gadget that's helping me breathe is configured... I asked them about this when I was there, and it was clear that they couldn't 100% explain how the pressure support worked, or the fact that while in the 'spontaneous mode' you can set specific initial max/min i&epap levels, but in auto mode, it looks like you can only set a single max ipap and min epap - but not the other way around. So without ramping, how does it know where to start?

thanks much