ASV users: the everything ASV thread.

[dsm]

Fan speed & load.

Re the Bipap Auto SV models std & advanced (this does not apply to the new PR ASV).

The motors on both those models run at a continuous speed. Any variation is miniscule and only occurs if there is a rapid load shift in how the air is directed. The air direction is controlled by a high-speed 'air valve'. The pumped air can be directed back into the fan input or out into the patient air hose.

Restated. Both these older machines pump the air inside the machine at a fixed rate, the 'air valve' controls where the air goes. This air valve can direct minute increments of air flow either back into the input side of the fan motor or out into the patient air circuit. The air valve is a brilliant (but rather expensive) device built on the same principles that drive the cone of a loud speaker.

The point here is that the air being redirected back into the fan does decrease the load on the motor a tiny bit. The air being switched to the external hose does increase the load a tiny bit. The only parts in the motor that can wear are the bearings. The motors are of the DC brushless types with no other moving part than the rotor/fan & the two bearings. The rotor includes a 'rare-earth' magnet & thus is a one piece solid component.

Setting the max pressure on the machine doesn't change the speed of the motor. It merely regulates the maximum position the air valve will shift to to switch air into the outside hose. As so many posters have already mentioned, the machine does not go to max pressure very often at all. If it did, that would add a small load onto the fan motor's bearings. Good 'high-speed' bearings should last for many years. The ones shown in the link suffered from water damage when the owner (an RT) put the machine into its carry bag while there was water in the H/H.

Anyone interested in what the older Bipaps look inside can take a peek at these links. Click any image to enlarge it - you can navigate fwd & back.

Here is a Bipap Pro 2 (same internals as a Bipap Auto SV (apart from the motherboard) - it shows the air valve clearly ...
http://www.internetage.ws/cpapinfo/rems ... index.html

Here is a bipap Auto SV taken apart ...
http://www.internetage.ws/cpapinfo/bipa ... index.html

DSM

#2 - if you look into the base of the machine in link 1 (pic #8) , you can see a 'false bottom'. There is a hollow compartment there. The fan sits on the bottom & draws air up through the hole seen in the base. The excess airflow (that is not required for the patient air hose) is directed from an outlet in the air valve into that opening on the side of the case & back into the hollow base.

#3 - to follow the airflow see pic #7 in link 1. The air goes into the fan through the opening visible in the middle of the fan assembly (that opening normally sits flush down on the hole in the base of the case). The fan pumps the air out its side nozzle into one end of the air valve. The air valve directs some air to the air hose outlet (that is the exit on the side of the air valve). The remaining air goes out the far end of the air valve which normally sits flush on the opening in the side of the case, that air flows back down into the hollow base & can then be sucked back into the fan again.

[ameriken]

July 18-19.

EPAP= 4
PSmin= 3

AHI for the past 5 nigths: 6, 6, 5, 7, 9. Not sure what to think of this.

A couple of 30 to 45 minute naps in the past few days were as high as 18 and 23.

[adipasqu]

July 18-19.

EPAP= 4
PSmin= 3

AHI for the past 5 nigths: 6, 6, 5, 7, 9. Not sure what to think of this.

A couple of 30 to 45 minute naps in the past few days were as high as 18 and 23.

How do you feel? My numbers got worse before they got better, but I was feeling better. Could be some of the same in your case.

-A

[rested gal]

A couple of 30 to 45 minute naps in the past few days were as high as 18 and 23.

I don't use an ASV, but I have noticed on my data from any machine I use, AHI is often reported much higher from a short nap session (like the 30 - 45 minute naps you mentioned) than from a sleep session of two hours or more. I completely disregard the short nap AHI's.

1 even in a single one minute session is an AHI off 60. What makes that "accurate"?

If you have 4 events half an hour after you fall asleep, and sleep for an hour, your AHI will be 4. If you have no more events and keep on sleeping for 4 hours, you'll have an AHI of 1. That's math. I simply ignore shot sessions.

viewtopic.php?p=386775#p386775

[ameriken]

July 18-19.

EPAP= 4
PSmin= 3

AHI for the past 5 nigths: 6, 6, 5, 7, 9. Not sure what to think of this.

A couple of 30 to 45 minute naps in the past few days were as high as 18 and 23.

How do you feel? My numbers got worse before they got better, but I was feeling better. Could be some of the same in your case.

-A

I think maybe slightly better, the headaches are minimal. I was able to get through yesterday without a nap, which I thought was pretty good.

I the one of the reasons it's hard to explain how I feel is because it still takes me a little while to wind up in the morning but I'm able to function well throughout the day. I wake up thinking I didn't have a good night and not feeling so great, but then as the day progresses I start feeling better.

[ameriken]

A couple of 30 to 45 minute naps in the past few days were as high as 18 and 23.

I don't use an ASV, but I have noticed on my data from any machine I use, AHI is often reported much higher from a short nap session (like the 30 - 45 minute naps you mentioned) than from a sleep session of two hours or more. I completely disregard the short nap AHI's.

1 even in a single one minute session is an AHI off 60. What makes that "accurate"?

If you have 4 events half an hour after you fall asleep, and sleep for an hour, your AHI will be 4. If you have no more events and keep on sleeping for 4 hours, you'll have an AHI of 1. That's math. I simply ignore shot sessions.

viewtopic.php?p=386775#p386775

I was thinking about that yesterday, I might pull the card out when I take a nap so it doesn't throw my numbers out of whack.

[adipasqu]

July 18-19.

EPAP= 4
PSmin= 3

AHI for the past 5 nigths: 6, 6, 5, 7, 9. Not sure what to think of this.

A couple of 30 to 45 minute naps in the past few days were as high as 18 and 23.

How do you feel? My numbers got worse before they got better, but I was feeling better. Could be some of the same in your case.

-A

I think maybe slightly better, the headaches are minimal. I was able to get through yesterday without a nap, which I thought was pretty good.

I the one of the reasons it's hard to explain how I feel is because it still takes me a little while to wind up in the morning but I'm able to function well throughout the day. I wake up thinking I didn't have a good night and not feeling so great, but then as the day progresses I start feeling better.

You're still recovering from sleep debt. I've been there. Be patient and it will pay off, I promise. I am a new person now, but it has taken almost 3 months of ASV (and tweaking my therapy) to get me there. And, I'm sure, I still have a ways to go. Each day gets better for me, and it will for you.

-Antonio

[adipasqu]

A couple of 30 to 45 minute naps in the past few days were as high as 18 and 23.

I don't use an ASV, but I have noticed on my data from any machine I use, AHI is often reported much higher from a short nap session (like the 30 - 45 minute naps you mentioned) than from a sleep session of two hours or more. I completely disregard the short nap AHI's.

1 even in a single one minute session is an AHI off 60. What makes that "accurate"?

If you have 4 events half an hour after you fall asleep, and sleep for an hour, your AHI will be 4. If you have no more events and keep on sleeping for 4 hours, you'll have an AHI of 1. That's math. I simply ignore shot sessions.

viewtopic.php?p=386775#p386775

I was thinking about that yesterday, I might pull the card out when I take a nap so it doesn't throw my numbers out of whack.

That's not a bad idea. Especially, if not seeing bad numbers from a short session makes you feel better about the therapy.

-A

[ameriken]

That's not a bad idea. Especially, if not seeing bad numbers from a short session makes you feel better about the therapy.

As long as the naps don't mean anything, I'm not worried about it. However when I go see to the Dr next month, I don't want to bring him an AHI that is skewed up or down because of the naps.

[ameriken]

You're still recovering from sleep debt. I've been there. Be patient and it will pay off, I promise. I am a new person now, but it has taken almost 3 months of ASV (and tweaking my therapy) to get me there. And, I'm sure, I still have a ways to go. Each day gets better for me, and it will for you.

-Antonio

Thanks Antonio, those words mean a lot. Really. I appreciate your help and encouragement and hope one day I can provide the same to someone else here.

I've thought about pulling the mask off for one night just to compare how I felt before with how I feel now, but when I think about how I felt before I started on xPAP, I cancel that idea. I felt so damned awful over the past year that I was often wondered if I would even make it to xPAP. And when my sleep Doc called me after my first PS back in March and he was all freaked out about my O2 levels, that didn't help.

Looking back, I can say I am definitely far better than what I was.

[adipasqu]

Looking back, I can say I am definitely far better than what I was.

And that's all that matters in the end. Numbers be damned!!! Do you have a pulse oximeter or access to one? You might want to ask your sleep doc if they can loan you one for a while to see if your saturation are at good levels under ASV therapy.

-A

[ameriken]

Looking back, I can say I am definitely far better than what I was.

And that's all that matters in the end. Numbers be damned!!! Do you have a pulse oximeter or access to one? You might want to ask your sleep doc if they can loan you one for a while to see if your saturation are at good levels under ASV therapy.

-A

I've been thinking about buying one, but I'm not sure how good or accurate they are, there's a thread going on that with some good input, but I haven't decided on buying one yet. That's one of the things I want to talk to him about is seeing where my O2's are at.

[adipasqu]

Looking back, I can say I am definitely far better than what I was.

And that's all that matters in the end. Numbers be damned!!! Do you have a pulse oximeter or access to one? You might want to ask your sleep doc if they can loan you one for a while to see if your saturation are at good levels under ASV therapy.

-A

I've been thinking about buying one, but I'm not sure how good or accurate they are, there's a thread going on that with some good input, but I haven't decided on buying one yet. That's one of the things I want to talk to him about is seeing where my O2's are at.

I like my CMS-50F. The wristband could be better (I may end up making my own out of some neoprene or something), but otherwise it's a nice and affordable wrist oximeter. They don't have to be super accurate to see the desaturations vs. events, which is the important thing.

-A

[Bright Choice]

I like my CMS-50F. The wristband could be better (I may end up making my own out of some neoprene or something), but otherwise it's a nice and affordable wrist oximeter. They don't have to be super accurate to see the desaturations vs. events, which is the important thing.

-A

Yes, that wristband it really weird. Two work arounds: 1. Cut the extra strap "flaps" off. I have no idea what they are there for. Works fine without the flaps. 2. I bought an $8 watch band with velcro closure at Walmart. I like this solution best.

Either way it is a bit of a "squeeze" to get the band on. Be gentle so you don't break the oximeter but you can ease the strap on.

[adipasqu]

I like my CMS-50F. The wristband could be better (I may end up making my own out of some neoprene or something), but otherwise it's a nice and affordable wrist oximeter. They don't have to be super accurate to see the desaturations vs. events, which is the important thing.

-A

Yes, that wristband it really weird. Two work arounds: 1. Cut the extra strap "flaps" off. I have no idea what they are there for. Works fine without the flaps. 2. I bought an $8 watch band with velcro closure at Walmart. I like this solution best.

Either way it is a bit of a "squeeze" to get the band on. Be gentle so you don't break the oximeter but you can ease the strap on.

I almost sent you a message on how to install the dang thing. Whomever came up with that design and chose that material should be fired!

-A