What is ASV?

I'm guessing auto serve ventilation...but what does that mean? Does it mean it only gives you extra pulses of air when you fail to make any inspiratory effort due to central sleep apnea, or obstructive apnea? I have a PR bipap ST which provides 12 bpm because I have central apnea as well as obstructive. I'm curious as to whether there are other machines out there that perform similarly, and whether any of those users are on this forum. I would love to chat with anyone having either/both kinds of sleep apnea. I don't know anyone else that does, and it'd be very helpful if someone could chat with me.

Asv treat central apneas. It has a back up rate like the unit you have. The difference is the st delivers a set pressure and the asv has varying pressures that hunt around your breathing patterns to give you the pressure you need at that time. Asv treat centrals more thoroughly than st

Thanks so much for explaining the difference to me. That sounds like it would be a much better system than what I have. I'll talk to my doc about it when I see him next week.

An ASV unit is an Adaptive Servo-Ventilator. Essentially that name means that it adapts to your breathing and "servos" the adaption (or ties the adaption) to your breathing. If you fail to breathe (due to a central sleep apnea), then it ramps up the pressure and acts as a ventilator.

You see, regardless of the cause of the central sleep apnea (heart issues, reaction to pressure, or central nervous system disorder), central sleep apneas occur due to a undershoot/overshoot cycle. For whatever reason our bodies fail to breathe as we should. The CO2 builds up in our blood stream. This is the undershoot side of the cycle. Our bodies simply do not breathe as they should to meet our needs. As the CO2 builds up, it eventually causes our bodies to resume respiration. That resumption of respiration tends to come with a slight hyperventilation (breathing a little bit faster than normal). This causes our bodies to blow off more CO2 than they normally would. This is the overshoot side of the cycle. That is, our bodies overdo the respiration just enough that they blow off too much CO2. This tends to depress respiration. And suddenly we are back on the undershoot side of the cycle. We fail to breathe as we should and the CO2 starts to build. This cycle tends to occur over and over and over if someone has central sleep apnea.

By jumping into the middle of this, the ASV unit acts as a ventilator and starts to help with respiration - even when we are not breathing. To do this, it increases the pressure within just a few breaths to support our respiration. By helping support our respiration, it helps decrease the build up of CO2, which helps break the cycle.

As a result, it is not unusual to see someone with an ASV unit have an AHI of 1 or 2 at the most. Often an AHI of zero is attained.

Hope that helps explain what an ASV unit is and does for you. If you have central sleep apnea (as you do), then I would suggest you mention stress that (as you note in another post) the ST unit you currently have does not seem to meet your needs and you would like to be titrated with an ASV unit. Sometimes you have to be pretty insistent to get them to do that. Also be aware that the cost of an ASV unit is a LOT higher than other units. But it makes a huge difference.

JohnBFisher wrote:An ASV unit is an Adaptive Servo-Ventilator. Essentially that name means that it adapts to your breathing and "servos" the adaption (or ties the adaption) to your breathing. If you fail to breathe (due to a central sleep apnea), then it ramps up the pressure and acts as a ventilator.

You see, regardless of the cause of the central sleep apnea (heart issues, reaction to pressure, or central nervous system disorder), central sleep apneas occur due to a undershoot/overshoot cycle. For whatever reason our bodies fail to breathe as we should. The CO2 builds up in our blood stream. This is the undershoot side of the cycle. Our bodies simply do not breathe as they should to meet our needs. As the CO2 builds up, it eventually causes our bodies to resume respiration. That resumption of respiration tends to come with a slight hyperventilation (breathing a little bit faster than normal). This causes our bodies to blow off more CO2 than they normally would. This is the overshoot side of the cycle. That is, our bodies overdo the respiration just enough that they blow off too much CO2. This tends to depress respiration. And suddenly we are back on the undershoot side of the cycle. We fail to breathe as we should and the CO2 starts to build. This cycle tends to occur over and over and over if someone has central sleep apnea.

By jumping into the middle of this, the ASV unit acts as a ventilator and starts to help with respiration - even when we are not breathing. To do this, it increases the pressure within just a few breaths to support our respiration. By helping support our respiration, it helps decrease the build up of CO2, which helps break the cycle.

As a result, it is not unusual to see someone with an ASV unit have an AHI of 1 or 2 at the most. Often an AHI of zero is attained.

Hope that helps explain what an ASV unit is and does for you. If you have central sleep apnea (as you do), then I would suggest you mention stress that (as you note in another post) the ST unit you currently have does not seem to meet your needs and you would like to be titrated with an ASV unit. Sometimes you have to be pretty insistent to get them to do that. Also be aware that the cost of an ASV unit is a LOT higher than other units. But it makes a huge difference.

I know this is a three year old thread, but someone just linked it and wow, great explaination of it! Thanks John