Can you still have central apneas on ASV??

[Michaely6]

I have a resmed ASV and was just wondering if it is still possible to have central apneas while on an ASV machine or does the machine take care of all centrals with the backup rate?

[SarcasticDave94]

My opinion would be that centrals could occur if the settings aren't right for the user. The ASV, like all other xPAP machines, need dialed in for the individual. No machine can do its job properly without being enabled to function correctly via the correct settings, per said individual needs.

[Crimson Nape]

I agree with Dave. If the ASV, or any CPAP, isn't properly adjusted then it can't address the patient's apneas and/or hypopneas.

[Michaely6]

Thanks for the feedback guys!

[jaswilliams]

But the machine won't report the event as a CA as it only reports UA's and Hypopnea

[Michaely6]

So the only way to know is to look at the flow graph in sleepyhead huhh

[Walla Walla]

If I understand ASV machines which is probably questionable. Clear apnea events never go away. That's the purpose of the backup forced breaths the machine gives you. What the machine does is adjust pressure for obstructive events while providing assisted breaths for clear apnea events. So aside from the breaths per seconds settings there's no other adjustment to be made for clear apnea.

OK now everyone can correct me.   

[Michaely6]

If I understand ASV machines which is probably questionable. Clear apnea events never go away. That's the purpose of the backup forced breaths the machine gives you. What the machine does is adjust pressure for obstructive events while providing assisted breaths for clear apnea events. So aside from the breaths per seconds settings there's no other adjustment to be made for clear apnea.

OK now everyone can correct me.   

Your logic on that actually makes alot of sense!!

[sheepless]

as I understand it the asv resolves ca and periodic breathing without user intervention.  unlike other bilevel's , with asv there is no setting for back up breaths; it's built into the algorithm.  from resmed's website advertising:

"The AirCurve 10 ASV bilevel machine offers truly personalized therapy for central breathing disorders, such as Cheyne-Stokes respiration (CSR), central sleep apnea (CSA) and associated obstructive events. Featuring the most clinically-studied and proven ASV algorithm, AirCurve 10 ASV is the only adaptive servo-ventilator that targets the patient’s own recent minute ventilation.

ASV mode
The clinically-published ASV algorithm constantly learns, responds, predicts and synchronizes with the patient’s respiratory pattern to help rapidly stabilize respiration.

The pressure support varies to respond to the patient's need. Mandatory breaths are delivered at the patient’s recent spontaneous breath rate.  [my emphasis]

ASVAuto mode
In ASVAuto mode, this bilevel machine not only responds within the breath, adjusting Pressure Support to stabilize respiration, it also automatically adjusts the expiratory pressure in order to provide the minimum pressure required to maintain upper airway patency. It analyzes the state of the patient’s upper airway on a breath-by-breath basis and delivers expiratory pressure within the allowed range."

edit: I should add that I think it's odd that all apnea are unclassified if clear or central's are automatically resolved. still, there seems to be a presumption that unclassified apnea is obstructive.

[jaswilliams]

The reason the apnoea is classed as unclassified is that an ASV does not do the Forced Oscillation technique (It's busy doing it's thing) so it does not know if the apnoea are CA's or obstructive. By looking in detail at the flow to can some times tell but I don't have enough events remaining at night to worry about, my treated AHI is often 0 occasionally 0.24 my CA's if they flag anything flag as hypopnoeas the machine blew as hard as it could and I only took a partial breath.