[Equipment] ASV reacting too early when falling asleep

[antstephenson]

Hi guys/girls,

On Monday, I was finally prescribed with an ASV, and so far my data appears to be good (http://www.apneaboard.com/forums/Thread-...ess?page=4), however, right now I'm struggling to fall asleep easily due to the machine reacting to my slow breathing prior to falling asleep and it increases the pressure and startles me, I found that I can turn ramp on which appears to disable the ASV capabilities and make it like my previous AutoSet machine, but I find it difficult to sleep with ramp in general, as I end up counting down and keeping myself awake when I know the ramp will finish. I persevered without it on my AutoSet and finally became comfortable with falling asleep easily with it. Another issue is if I enable a long ramp (40-45 mins is the max, afaict), if I fall asleep fast, I end up having events.

Anyway, I was reading online that the ASV I have (See the sidebar <----) automatically calibrates based on my breathing, it's in AutoASV mode and I would highly prefer leaving it in that mode as my clinician has set that and advised me to only fiddle with the EPAP for comfort (which I raised to 5.00 based on comments in my previous thread).

So my questions are; should I persevere by switching off the ramp and will the machine learn my breathing patterns? I've used it for 40 mins without ramp on my first night and didn't actually fall asleep, so any calibration that would of occured whilst awake didn't happen after this. My other question is if anyone else found felt the same as me and simply got familar with the way it worked?

Thanks everyone in advance!

Ant

[sheepless]

what you describe is the nature of the beast I think. you'll get used to the machine nudging you to breathe during sleep onset. after a while you'll be grateful for the relief you get by breathing more properly. when it happens you can either exhale sharply against it to lower the pressure or follow its prompt to inhale. I always do the latter unless I'm leaking a lot or its plugging my ears or forcing air into my stomach. initial pressure isn't uncomfortable so I don't use the ramp. didn't like it with apap either.

[antstephenson]

Hi,

Thanks for the comments! actually the "initial pressure" isn't a problem for me, my EPAP min is at 5.00 which is perfectly adaquate, just turning on ramp actually disables the reactive nature of the ASV. I'm gonna give it another go tonight without the ramp feature and see what happens.

[sheepless]

other more-experienced members might have suggestions for adjusting pressures to reduce the impact of the machine at work (pressure swings); maybe adjusting / raising min pressure support, but I'm still figuring the machine out myself so wait for others to chime in. meanwhile, your profile shows cpap pressure 4-19. that doesn't sound complete for asv(auto). you should have min & max epap and min & max pressure support. it should also show min & max ipap but that can be figured from epap + ps.

[jaswilliams]

When your ASV starts to Breath for you when falling asleep blow back at it hard and it will stop breathing for you for the next 3 minutes and it will Sync with your new reduced breath rate. Over time everything syncs up and and this issue will go away.

[Spy Car]

What you are describing (a sudden increase in pressure just as ones breathing slows down as one enters the sleep transition) is exactly what I experienced with the ResMed ASV machine. From reports of others, it seems typical. Annoying, but not unusual.

The good news it this problem seems to go away.

It seems like the best response to the pressure increase is to exhale forcefully into the mask when this happens. This has been dubbed the "blowback" method by ASV users here on the forum. Doing this settles the machine down.

I'm not sure if the machine learns our patterns, or if it rains us, or if it is a little of both, but I (and most users) seem to fall into sync with the machine over a couple of weeks.

It is a pain to have the ASV blast at the most critical moment of sleep transition. It is the one complaint I have with an otherwise brilliant device.

Hang in there. Use the blowback method. And expect it will get better.

Bill

[squid14]

Nothing more to add, it's been pretty well covered, it's something we all go thru when you switch to an ASV and believe it or not you will adjust to it. I've been using one for 6 years and couldn't sleep without it.

[SarcasticDave94]

Welcome to Apnea Board. I'll Ditto very strongly to try the Blowback method. The ASV will learn IMO and it tends to reset the therapy, at least it feels like it to me. When I use blowback, I focus on my breath rate, pattern, etc, making sure I'm not going too deep or shallow and keeping a "regular" flowing breath rhythm as it is supposed to be.

As for the Ramp, I personally can't use it period. It cuts therapy time and I don't like the transition from ramp back to the regular ASV therapy program.

Hope this helps and best wishes for great successes to your ASV therapy. I know the ASV machine can and will deliver, keep plugging away.

[DeepBreathing]

I've been using the Aircurve 10 for a few weeks while my old S9 was in for warranty work. The 10 is slightly more aggressive in the way it delivers pressure support, and I found that I had to reduce PS Max by a few points to allow me to get to sleep. The downside of that, of course, is that my AHI went up a bit.

The blowback method described above does seem to work, but it's better to get yourself into a nice regular breathing pattern so the machine can synch with you more easily.

As for ramp, I found the transition at the end of the ramp period always resulted in a distinct pressure pulse - it's much better to use these machines without ramp if you can do so.

[antstephenson]

Ah guys honestly I'm really happy to see some concensus on a possible solution and that I'm not the only one whos experiencing/experienced this. I'm going to try what you've suggested tonight and see how it goes, last night I got fed up and took it off after about 1:30h.