new ASV user-questions

[flocof]

Hi, I was on S9 Resmed Auto and had residual AHI of around 12-19 with around two thirds CA, and the rest OA. I am on a trial with a PR ASV auto and I don't have any detailed information as I don't have a card reader yet, but as I had to go to the Hospital today for another reason I asked for a readout of my smartcard. I still have an average AHI of 10 with mostly Hypopneas and about 1:OA and 1:CA. Does anyone know what that means and why the hypopneas are higher now? and what are they?
I will be seeing the doc at the end of the month, but I would like to know in the meantime...I am very curious

[JohnBFisher]

It might mean that your exhalation pressure needs to be increased slightly. That is, rather than have the hypopneas develop into full blown apneas, the unit addresses the issue. However, with the lower exhalation pressure it can not stop the hypopneas.

The good news is that many of us find that while hypopneas are disruptive to our sleep they do not leave us feeling as miserable the following day. Sounds as if the ASV unit is doing a pretty good job with your therapy. Hope the trend continues for you.

[flocof]

Thanks John. So what exactly are hypopneas? My settings are at 10 with 7 exhale. Does that sound reasonable? and when you say it should be increased, you mean exhale should be tried with 8?

[Mary Z]

flocof, "Hypopnea: A respiratory episode where there is partial obstruction of the airway lasting greater than 10 seconds. Also called partial apnea or hypo-apnea. "
You should have more settings than two- min EPAP, Max EPAP, PS- Min and Max, and max pressure (IPAP). Unless this unit can be set up as a straight Bilevel....

[Grand-PAP]

what exactly are hypopneas?

Hi flocof,

Here's a very basic explanation:

Apnea is a Greek word that means "want of breath."

Hypopnea is a Greek word that means "underbreathing."

Hypopneas and apneas are both events in which there is a reduction in airflow. Which event is scored will be determined by the degree of reduction in airflow.

An apnea will be scored when the airway collapses ("obstructive apnea") and there is no airflow or when there is no obstruction ("clear airway apnea"), but there is no airflow.

Hypopnea is breathing that is shallower or slower than normal. By definition, a hypopnea is an event in which there is a drop in airflow ≥ 30% from baseline lasting for at least 10 seconds and associated with a ≥4% desaturation.

I don't remember the exact percentage and I couldn't locate the article, but I "think" that PR uses a 40% reduction is airflow to score a hypopnea.