ASV users: the everything ASV thread.

[BrianinTN]

Encore rounds up when the fractional component >= .4 Makes it nightmarish to match it's calculations, so I don't even bother any more with my stuff - I prefer accuracy over familiarity..

If you look closely at his CA, it's thicker.. There's a few events there crammed together, which up's the CA indice value a bit.. Still not enough for Encore to make any sense.

Thanks for the correction. I thought it was thicker but should have zoomed in rather than assumed. Mea culpa on both counts.

[ameriken]

Min PS = 5.
EPAP now is at 5.

If I drop the EPAP to 4, is it necessary to drop the Min PS to 4 as well or are those number separate from each other? (In other words, if EPAP = 4 and Min PS = 5, would the Min PS keep the EPAP at 5 regardless of my dropping EPAP to 4?)

Also, looking at my report at the # of CA's, I do notice there are more events than any other night, usually I'll see only 1 CA event in a night, if even that. Last night shows at least 3 events.

[adipasqu]

Encore rounds up when the fractional component >= .4 Makes it nightmarish to match it's calculations, so I don't even bother any more with my stuff - I prefer accuracy over familiarity..

If you look closely at his CA, it's thicker.. There's a few events there crammed together, which up's the CA indice value a bit.. Still not enough for Encore to make any sense.

Thanks for the correction. I thought it was thicker but should have zoomed in rather than assumed. Mea culpa on both counts.

Actually, Brian has it right on the old ASV unit. There is a bug that rounds everything up for some reason. I would have maybe one OA flag and one CA flag for the night, with 10 hours of sleep for example, and both would be reported as 1.0 for OAI/CAI and add 2.0 to the HI to give an inflated AHI for the night. While on my old machine, I would hand calculate my indices from the flags and my AHI for the night would usually be 1 to 2 points lower than reported from Encore (although I think the bug is in the machine and not in the software, because this issue did not display itself when I was on APAP before ASV using the same software).

[adipasqu]

Min PS = 5.
EPAP now is at 5.

If I drop the EPAP to 4, is it necessary to drop the Min PS to 4 as well or are those number separate from each other? (In other words, if EPAP = 4 and Min PS = 5, would the Min PS keep the EPAP at 5 regardless of my dropping EPAP to 4?)

Also, looking at my report at the # of CA's, I do notice there are more events than any other night, usually I'll see only 1 CA event in a night, if even that. Last night shows at least 3 events.

They are separate, but realize what is going on with both at 5. Initially, you are inhaling at 10 cm and exhaling at 5 cm. That's a big difference and probably too big for most of the night. I suspect this is causing you to be hyperventilated and suppressing your own body's spontaneous breathing. If you drop PSmin to 3, or lower perhaps, your spontaneous breathing will increase and you will likely feel even better! Remember, you are just setting lower limits for the machine to take over and adapt to what you need at any given point time. I feel it is important to give the ASV machine a wide window in which to operate for effective therapy. At least, that has been my experience.

-A

[ameriken]

They are separate, but realize what is going on with both at 5. Initially, you are inhaling at 10 cm and exhaling at 5 cm. That's a big difference and probably too big for most of the night. I suspect this is causing you to be hyperventilated and suppressing your own body's spontaneous breathing. If you drop PSmin to 3, or lower perhaps, your spontaneous breathing will increase and you will likely feel even better! Remember, you are just setting lower limits for the machine to take over and adapt to what you need at any given point time. I feel it is important to give the ASV machine a wide window in which to operate for effective therapy. At least, that has been my experience.

-A

Interesting, thanks for the explanation. I took a 30 minute nap a little while ago and beforehand, I decided to drop EPAP to 4 and minPS to 4.

I know naps are not the best judge of what's going on, but my AHI was 25, my worst ever under any circumstance with an ASV. Also, I dont know what the tech term is for this, but when exhaling I felt like I was snoring...it was like snoring in reverse. I've noticed this from time to time before, but this time it was more frequent.

The ASV pushed my EPAP to 5 nearly the whole time. So, I may leave my EPAP at 5 and experiement with perhaps dropping minPS to 4 or 3.

[adipasqu]

Interesting, thanks for the explanation. I took a 30 minute nap a little while ago and beforehand, I decided to drop EPAP to 4 and minPS to 4.

I know naps are not the best judge of what's going on, but my AHI was 25, my worst ever under any circumstance with an ASV. Also, I dont know what the tech term is for this, but when exhaling I felt like I was snoring...it was like snoring in reverse. I've noticed this from time to time before, but this time it was more frequent.

The ASV pushed my EPAP to 5 nearly the whole time. So, I may leave my EPAP at 5 and experiement with perhaps dropping minPS to 4 or 3.

Yeah, I wouldn't put too much stock in your nap data. Try 4 and 4 tonight and we'll see how it compares with last night.

-A

[ameriken]

I'm not going to go quite that low on the EPAP yet, I'm leaving it at 5, but I will lower the minPS to 4.

This ASV stuff seems more and more like art than science.

[adipasqu]

I'm not going to go quite that low on the EPAP yet, I'm leaving it at 5, but I will lower the minPS to 4.

This ASV stuff seems more and more like art than science.

Sounds good to me. Some might say art, others might say magic...

[ameriken]

July 13-14. EPAP set at 5, minPS set at 4. Not feeling to great this morning. AHI 6. Oddly, I woke up early this morning snoring in my mask which is evidenced by the cluster of VS's in hours 4 and 5. Also odd is the OA that I had.

[adipasqu]

July 13-14. EPAP set at 5, minPS set at 4. Not feeling to great this morning. AHI 6. Oddly, I woke up early this morning snoring in my mask which is evidenced by the cluster of VS's in hours 4 and 5. Also odd is the OA that I had.

EPAP stayed at your EPAPmin almost the entire night... Were you asleep when that OA occurred? I wouldn't worry about a single OA flag, even less so in that position of your sleep graph. No PB and no CA, that's good. With the VS, could you have been a little congested last night? I take it you were awake for the bad PTB cluster between 4-5 hours? Same thing happens to me if I wake up and try to fall back to sleep. You awake, ABR goes down, tidal volume goes up, CO2 concentrations reduce, and spontaneous breathing is suppressed. I need to figure out why I can no longer sleep through the night, too...

-A

[ameriken]

July 13-14. EPAP set at 5, minPS set at 4. Not feeling to great this morning. AHI 6. Oddly, I woke up early this morning snoring in my mask which is evidenced by the cluster of VS's in hours 4 and 5. Also odd is the OA that I had.

EPAP stayed at your EPAPmin almost the entire night... Were you asleep when that OA occurred? I wouldn't worry about a single OA flag, even less so in that position of your sleep graph. No PB and no CA, that's good. With the VS, could you have been a little congested last night? I take it you were awake for the bad PTB cluster between 4-5 hours? Same thing happens to me if I wake up and try to fall back to sleep. You awake, ABR goes down, tidal volume goes up, CO2 concentrations reduce, and spontaneous breathing is suppressed. I need to figure out why I can no longer sleep through the night, too...

-A

The snoring woke me up, and perhaps that is when I had the OA, but I fell right back asleep. I also barely remember a large pressure increase waking me up, which also could have been an OA. Other than that, I was out the rest of the night.

As for EPAP, it seems like no matter what the EPAP min is, it always increases by 1 or 2. If set at 7, I'll see it push to 8 a few times. If I have it at 6 it'll push to 7. If at 4, it'll push to 5. But I don't understand why if at 7 it'll push to 8, but if set at 4 it won't push to 8. That kinda baffles me a little.

[adipasqu]

As for EPAP, it seems like no matter what the EPAP min is, it always increases by 1 or 2. If set at 7, I'll see it push to 8 a few times. If I have it at 6 it'll push to 7. If at 4, it'll push to 5. But I don't understand why if at 7 it'll push to 8, but if set at 4 it won't push to 8. That kinda baffles me a little.

This is a good thing. This is the machine telling you you don't need a high EPAP to keep your throat open (i.e. obstructions seem not to be your main problem). This is why I am most curious about what will happen when you set EPAPmin to 4. Will it stay at 4 cm 95% of the night or more? If yes, then EPAPmin of 4 is probably the right setting (can't go any lower). If you set it to 4 cm and it goes up to 5 cm for 95% of the night or more, then 5 cm is probably your right EPAPmin setting. As for PS, this is related to centrals. Although your CA is clear last night, I'm willing to bet most of your hypopneas are central since many of them line up with decreases in your PTB. Lower PSmin, hypops decrease and PTB increases would be my hope. So, you have a choice of two different experiments: 1) lower EPAPmin to 4 and see what percentage of the time it stays at 4, or 2) lower PSmin one more notch to see of the hypops reduce in number and PTB increases. Did you take any methadone later in the day yesterday?

-A

[ameriken]

This is a good thing. This is the machine telling you you don't need a high EPAP to keep your throat open (i.e. obstructions seem not to be your main problem). This is why I am most curious about what will happen when you set EPAPmin to 4. Will it stay at 4 cm 95% of the night or more? If yes, then EPAPmin of 4 is probably the right setting (can't go any lower). If you set it to 4 cm and it goes up to 5 cm for 95% of the night or more, then 5 cm is probably your right EPAPmin setting. As for PS, this is related to centrals. Although your CA is clear last night, I'm willing to bet most of your hypopneas are central since many of them line up with decreases in your PTB. Lower PSmin, hypops decrease and PTB increases would be my hope. So, you have a choice of two different experiments: 1) lower EPAPmin to 4 and see what percentage of the time it stays at 4, or 2) lower PSmin one more notch to see of the hypops reduce in number and PTB increases. Did you take any methadone later in the day yesterday?

-A

No, I only took it in the morning, I am going to avoid taking it late in the day from now on unless the pain is unbearable, which if taken in morning I'm usually ok at night.

And you are correct, I think the centrals and low PTB's are the bigger problem for me, it was just surprising to wake myself snoring with the odd sound inside the mask.

I'll give one of those a try tonite and see what happens. If I go to EPAP=4, is it ok to leave minPS=4?

Thanks, I appreciate your input.

[adipasqu]

No, I only took it in the morning, I am going to avoid taking it late in the day from now on unless the pain is unbearable, which if taken in morning I'm usually ok at night.

And you are correct, I think the centrals and low PTB's are the bigger problem for me, it was just surprising to wake myself snoring with the odd sound inside the mask.

I'll give one of those a try tonite and see what happens. If I go to EPAP=4, is it ok to leave minPS=4?

Thanks, I appreciate your input.

First, it's my pleasure. We all need a little help at times and I am hopeful for you. 4/4 is just fine. If EPAPmin of 4 works well but hypops are still high, then its time to reduce PSmin.

-A

[ameriken]

First, it's my pleasure. We all need a little help at times and I am hopeful for you.

I'd like to see a few more ASV users chime in on this thread with both their problems and remedies. I originally started it for my own issues however I know I'm not the only ASV user trying to tweak this thing.

4/4 is just fine. If EPAPmin of 4 works well but hypops are still high, then its time to reduce PSmin.

-A

Sounds good, I'll give it a go and see what happens.

How are you doing with your own machine? Are you where you want to be yet?