Trilogy AVAPS vs ASV - Move the Debate Here

[Madalot]

There is an argument going in another thread regarding this subject and it was pointed out by cardsfan that the thread is really a horrible place to have the argument. AGREED.

Move it here.

It is being proclaimed that a patient using a Trilogy in AVAPS mode is essentially using the machine as an ASV. It's also being stated that the Trilogy, in AVAPS mode, IS an ASV machine. These quotes and statements are in dispute.

Carry on here. Leave that poor poster's thread alone.

[ajack]

I'm dialing in my ASV, you can see at 03:25 target ventilation. Why the ASV mode algorithm isn't a full non invasive ventilator, like the ST, ST-A iVAPS and avaps modes
I will be able to get it better by adjusting the epap and PS, but that isn't the point.
http://i.imgur.com/YGRaSjh.png

[TASmart]

You all might to look up borderline personality disorder, that's what the antagonist appears to be.

[palerider]

There is an argument going in another thread regarding this subject and it was pointed out by cardsfan that the thread is really a horrible place to have the argument. AGREED.

Move it here.

It is being proclaimed that a patient using a Trilogy in AVAPS mode is essentially using the machine as an ASV. It's also being stated that the Trilogy, in AVAPS mode, IS an ASV machine. These quotes and statements are in dispute..

there's no dispute... the proclamations are simply *WRONG*, by someone that doesn't know anything about the concept of VAPS (whether AVAPS by respironics or iVAPS from resmed).

You, as a long term user, obviously do know.

[Madalot]

There is an argument going in another thread regarding this subject and it was pointed out by cardsfan that the thread is really a horrible place to have the argument. AGREED.

Move it here.

It is being proclaimed that a patient using a Trilogy in AVAPS mode is essentially using the machine as an ASV. It's also being stated that the Trilogy, in AVAPS mode, IS an ASV machine. These quotes and statements are in dispute..

there's no dispute... the proclamations are simply *WRONG*, by someone that doesn't know anything about the concept of VAPS (whether AVAPS by respironics or iVAPS from resmed).

You, as a long term user, obviously do know.

Yes, I know he's wrong. You know he's wrong. Pretty much everybody with a brain knows he's wrong.

I'm hoping we can move it from the other thread because I agree that the argument belongs somewhere else. The OP's mother is on a Trilogy in AVAPS and whether a certain someone insists it's the same as an ASV is pretty irrelevant to the OP - and rightfully so.

Let that poor person spend the last time with their mother in peace. Argue all you (we??) want here.

[CPAPPED-ADAPT]

ASV is contraindicated for hypoventation. It is for hyperventilation syndrome, CSR and treatment-emergent complex apnea. You could perhaps kill someone who is severely underventilated (hypoventilation) by putting them on an ASV, they should be on a VAPS. I could be wrong, and someone please correct me if so, but I have several medical papers / presentations regarding this. Is this the accepted consensus here? I have been studying this a lot because my treatment-emergent complex apnea has been difficult to address. I also had confirmed this with my Sleep Doc, who seems quite knowledgeable in both ASV and VAPS technology.

[ajack]

alphabet, I don't kick my dog for drooling, it's what dogs do. I should treat you the same as I would treat a dog and let you have your delusions. What is being explained to you isn't getting through.

[ajack]

ASV is contraindicated for hypoventation. It is for hyperventilation syndrome, CSR and treatment-emergent complex apnea. You could perhaps kill someone who is severely underventilated (hypoventilation) by putting them on an ASV, they should be on a VAPS. I could be wrong, and someone please correct me if so, but I have several medical papers / presentations regarding this. Is this the accepted consensus here? I have been studying this a lot because my treatment-emergent complex apnea has been difficult to address. I also had confirmed this with my Sleep Doc, who seems quite knowledgeable in both ASV and VAPS technology.

That is right, an ASV is for a normal lung/respiratory function and treats periodic breathing. It is unsuited for more complex cases with base volume dysfunction.

[raisedfist]

ASV is contraindicated for hypoventation. It is for hyperventilation syndrome, CSR and treatment-emergent complex apnea. You could perhaps kill someone who is severely underventilated (hypoventilation) by putting them on an ASV, they should be on a VAPS. I could be wrong, and someone please correct me if so, but I have several medical papers / presentations regarding this. Is this the accepted consensus here? I have been studying this a lot because my treatment-emergent complex apnea has been difficult to address. I also had confirmed this with my Sleep Doc, who seems quite knowledgeable in both ASV and VAPS technology.

You are correct. ASV adjusts based on your actual ventilation and could quite easily lower pressure support when it actually needs to be increased. The ASV algorithm isn't designed to deal with the erratic breathing that can occur from respiratory problems.

Someone with hypoventilation is ventilating inadequately, so why would you want to replicate these patterns or target inadequate ventilation? The whole point of VAPS is to counteract inadequate ventilation by consistently providing an adequate volume of air for proper gas exchange to occur.

The only one who disagrees can simply type in Google "ASV contraindications" and you will get a plethora of results.

[ajack]

from what you have been reading adapt, you may have come across blood gas readings. That is also what determines whether an ASV is suitable. co2 retainers need the st or vaps

[raisedfist]

finally added asv boy to the foe list. are there like no mods on this site?

[ajack]

nope, no mods. he's having a wonderful time,

[robysue]

On the other thread, xxyzx wrote:

If she is using a mask, meaning non-invasive ventilation, then the Trilogy is simply assisting with breathing; the AVAPS mode just ensures adequate ventilation (assuming everything is set correctly). If she was sedated and/or unable to protect her airway, then she would be using invasive ventilation.

=====

and that is exactly what an ASV does

when the patient is not breathing it forces a RR and a given Vt
resmed and philips have different algorithms to determine RR and Vt
some machines let the dr. set the RR
the Vt really depends on the patient and their lungs so setting an average for everybody would not be as good as using the patients own Vt average

Nope. You still don't get it.

Most simply, in ASV mode there is NO target ventilation setting, but in AVAPS/iVAPS mode there is a target ventilation setting, and it plays a critical role in determining when an AVAPS machine steps in and how much additional pressure it provides to the patient.

It is true that in ASV mode the machine measures the tidal volume for the last several minutes so as to calculate the minute ventilation. And in ASV mode, the machine (internally) defines a target (minute) ventilation that is 90% of the moving average minute ventilation over the past several minutes. When the actual minute ventilation drops below that moving target, the machine decides you're in trouble and it starts to increase IPAP rather drastically until you start breathing more deeply on your own. In other words, in ASV mode, the machine expects the patient's last several minutes of regular breathing to reflect what the tidal volume and the minute ventilation should be at the current time.


In AVAPS mode, however, the target ventilation setting is a target for the desired tidal volume and this is usually based on the height and weight of the individual, but during a titration study the target ventilation setting can be adjusted to fit the patient's particular needs. (There is a protocol for adjusting it in the titration guidelines.) In the AVAPS algorithm enough pressure is applied to keep the actual tidal volume at or above the target ventilation setting at all times. In other words, the AVAPS does NOT use a running average of the tidal volume or minute ventilation, and the reason it does not use a running average is because the problem the patient is dealing with does not typically cause a very short term drop in minute ventilation, followed by hyperventilation, followed by more hypoventilation, etc. CSA is marked by this kind of hyperventilation-hypoventilation cycle; COPD and other restrictive respiratory problems are not. Rather a person with a restrictive respiratory problem has trouble maintaining an appropriate O2 saturation even during periods of normal breathing and their tidal volume may drop so slowly that it does not look like a hypopnea or the beginning of a CO2 undershoot/overshoot cycle (i.e. periodic breathing). So in essence the AVAPS doesn't trust the patient's last several minutes of regular breathing to necessarily reflect what the patient's current tidal volume ought to be.

Some useful links:

https://www.resmed.com/us/dam/documents ... lo_eng.pdf The Resmed titration guide. The discussion of Resmed's iVAPS algorithm starts on p. 25; the discussion of ASV starts on p. 27; an iVPAPS titration flow chart is found on p. 39, an ASV titration flow chart is found on p. 39, a sample iVAPS prescription can be found on p. 38, and a sample ASV Auto prescription can be found on p. 40. Information about billing codes for the VPAP ST-A starts on p. 45.

http://incenter.medical.philips.com/doc ... %3d9792335 The PR titration guide. The discussion of ASV starts on p. 13; the discussion of AVAPS starts on p. 17; sample scripts for both ASV and AVAPS are found on p. 19.

http://www.saegeling-mt.cz/fileadmin/us ... IntEng.pdf More detailed information about AVAPS---which patients it's for and explanation of how it helps their problems, from Philips Respironics

http://www.medtechnica.co.il/files/1402301644l44Ui.pdf Looks like a PowerPoint presentation with detailed information about properly titrating PR AVAPs machines, along with a pretty complete picture of what the Trilogy is capable of doing.

[palerider]

ASV is contraindicated for hypoventation. It is for hyperventilation syndrome, CSR and treatment-emergent complex apnea. You could perhaps kill someone who is severely underventilated (hypoventilation) by putting them on an ASV, they should be on a VAPS. I could be wrong, and someone please correct me if so,

You are not wrong.

[palerider]

finally added asv boy to the foe list. are there like no mods on this site?

the owners don't care.