(04-15-2016 10:26 PM)DeepBreathing Wrote: Gday Todd
I think one or two (or even five) apneas over the course of a night is no big concern. I know you're trying to target zero apneas but that's not realistic in the real world.
I agree, and I have to remind myself that prior to ASV my AHI was typically well over 10 for the four months during which I have data, and probably for several years before that. But based on what I've figured out so far, I feel best when it's below 3.
Quote:I am concerned about those really long obstructive apneas you're getting, even if they are isolated, and you might want to raise those with your doctor.
I have a followup visit in a few weeks, at which time I'll discuss that.
Quote:I come back to our original discussion - pressure support treats central apneas and EPAP treats obstructive events (hypopneas and obstructive apneas). However this needs to be nuanced considerably more than my limited knowledge allows. I have read an excellent paper by Javaheri, Brown & Randerath which goes into great deal of detail about how the algorithms of the Resmed, Philips and Weinneman machines work. I was interested to note that on the Philips, if hypopneas are detected it raises PS first followed by EPAP if there is no response to the PS increase. (Which I think is more or less what palerider said). On the other hand, the same machines do a "proactive search" to determine optimum pressures and will raise EPAP in response to hypopneas. The paper can be found here: http://journal.publications.chestnet.org...id=1891790
Thank you. That's going to take some study.
Quote:1. Check your settings to ensure you're in the auto EPAP mode (however that is described in Philips-speak). It looks like your EPAP is fixed on 9 and not varying. Otherwise don't make any further changes for at least a week
SH says I'm in "ASV (Variable EPAP)". I'll check what the machine says.
Based on SH, it looks like EPAP varies, but not that much. I don't know what expected variation is. The min value was 7.8 and max was 11.3 last night. (AHI 4.6, one OA, not lengthy).
Quote:2. Do not review your data every day - this can become an obsession which detracts from the real purpose of the therapy which is to get refreshing sleep
I hear you. That's pretty much what the sleep doc said last fall when I was getting agitated about the numbers on the DreamStation.
I have to say I believe there's a significant psychosomatic component to all this, which is not to say that it's entirely psychogenic. But I do think anxiety about AHI, CAs, OAs, and so on is conducive to increases in them. Not an easy not to crack for my personality type.
Quote:3. Do keep a sleep diary where each morning you note how you feel, what sort of night you had and whether you can make it through the day without excessive sleepiness.
Good idea. I pretty much always feel fine in the morning, but it's a question of whether later in the day I start to feel hungover, for lack of a better word. After a "bad" night, I'll notice things like sensitivity to glare and loud noises, which ordinarily wouldn't bother me.
Quote:5. Do something about those long obstructive events. Talk to your doctor, maybe consider whether you might have a positional problem (eg head flopping forward onto your chest) which could be exacerbating the obstruction.
Yes, I suspect something like this--especially back sleep. I've known for some time that if I end up on my back I'm likely to have a bad time, such as a nightmare of suffocating. Shouldn't there be an alarm in these machines when there's a prolonged OA?
Quote:Hope this helps
Yes, thank you.
Edit: For the record, I just found that the highest possible PSmin setting on my machine is 2, which is where I have it. The tech had set it to zero when it was delivered, and the titration study specified zero.