RE: How does ASV "deliver a breath"?
sheepless Wrote:can it actually complete an inhale and exhale without my participation? (to get the air in and let it out again?).
Yes, I think it can - that's the "ventilator" part of ASV. As SleepRider said above, it doesn't take a lot to inflate the lungs and exhalation is passive - when your lungs aren't being inflated the rib cage relaxes and forces the air out. So the ASV is not a hospital grade ventilator but can breathe for you, up to a point.
RE: How does ASV "deliver a breath"?
Sleepless, I just noticed your pressure in you avatar.
EPAP: 7.6 - 12 PS: 3.2 - 9
This tech explains ASV adjustment and pressure well, You might consider raising your max ps, at the moment your machine is restricted.
pick it up at the 12 minute mark.
youtube Bilevel and ASV Titrations: Pressure Changes for Technologists and Patients.
05-28-2019, 11:19 PM
(This post was last modified: 05-28-2019, 11:20 PM by idlewire.)
RE: How does ASV "deliver a breath"?
So, just curious -- this is probably for SleepRider -- what's the minimum pressure differential to allow an exhale? From the charts DeepBreathing posted, obviously pressure is not dropping to 0 for exhale. Let's say I'm inflating the lungs at 18cm, would a pressure drop to 17cm allow a (passive) exhale?
RE: How does ASV "deliver a breath"?
Having 18 epap and 18 ipap allows for a passive exhale. As in you don't need to consciously exhale, the body will do it. You would have noticed that it feels like your lungs don't fully empty on cpap, that is because of the min pressure holding open the air sacks. This is normal and a desired feature for some patients. With 18 14. The 4cm difference reduces breathing effort by about 50%.
Do you have a titration sleep study on the Vauto?
RE: How does ASV "deliver a breath"?
As usual I see things a little different. I thought I might need an ASV machine back at the start of things so I researched it a little. This is what I figured out. YMMV.
1. to "inflate the lungs" you must overcome the air pressure of the environment, just like with a balloon. no CPAP of any kind can do that. A true Ventilator CAN do that and CAN breathe for you.
2. The word ventilator technically does NOT mean to breathe for you, it means it blows air into you. This is just like a fan ventilates a house by blowing air into it. In the case of most medical equipment a Ventilator has come to mean "breathing for you", but then we look at the ASV and this does indeed use the generic meaning of Ventilator.
3.A CPAP (non-ASV) creates a pressure splint in your airway. It does not and cannot open an obstructive apnea, but once it detects that you have had one it will increase pressure to try and stop your next breath from being another apnea. IE it splints open your airway.
4. Obstructive apnea is just that, something is blocking you from inhaling. Central is where your brain stem does not even try to inhale. The ASV is timing your breathing and can detect when you "should" have inhaled.
5. ASV machines will give a pressure pulse when they detect that you have not taken a breath and will step up the pressure pulse to try and trigger you into taking a breath. It does not and cannot breath for you. The ASV machines can also handle Obstructive Apneas.
The difference on the machine side is that an ASV machine can directly treat a central apnea. If you don't have brain stem issues, but are having centrals it means that you need an adjustment to your CPAP settings or maybe a BiPAP CPAP machine that gives you more setting control to try and adjust out the centrals.
ASV machines have their own issues to get used to. The pressure pules can "startle" you and keep you awake. They are twice the cost of a BiPAP and you really don't want to use ASV mode unless you really need to.
