AHI and Pressure

[2bitwise]

I have a Resmed S9 and just started using Sleepyhead beta 0.95. Rescan 4.3 crashes my desktop during navagation. I uninstalled their drivers, but Win 7 crashes so bad I have to unplug my computer to recover.
When viewing Sleepyhead daily summary I get: AHI 1, Hypopnea(duration 1.5hrs), pressure and mask pressure do not change in response to the Hypop. The S9 is set to APAP mode. Why isn't the pressure changing? How accurate are the Sleepyhead graphs compared to Rescan?

[Pugsy]

Please post an image of your detailed report so we can see what you are seeing. If you don't know how see this thread as we discussed it and there's some examples. It helps us help you if we can see what you are seeing.
Screen shot thread viewtopic.php?f=1&t=81072&p=737779#p737779

The SleepyHead graphs are usually spot on in terms of how they compare to ResScan graphs.

[robysue]

When viewing Sleepyhead daily summary I get: AHI 1, Hypopnea(duration 1.5hrs), pressure and mask pressure do not change in response to the Hypop.

Not sure what you mean by "Hypopnea(duration 1.5hrs)". A single hypopnea is not going to last 1.5 hours.

The S9 is set to APAP mode. Why isn't the pressure changing? How accurate are the Sleepyhead graphs compared to Rescan?

I'm going to hazard a guess on this one: I suspect that you are looking at an "isolated hypopnea" or an "isolated obstructive apnea". The thing is: The auto algorithm is programed to NOT respond to isolated Hs and OAs if there is no snoring or flow limitation being detected. It takes two or more obstructive events (Hs or OAs) that happen very close to each other (like within 5 minutes of each other) to trigger the machine to increase the pressure for the events.

This mimics the AASM guidelines for manual titration of CPAP/BiPAP on attended titration sleep studies. The reason the guideline is there is at least partially to keep people from being over titrated.

[2bitwise]

I used F12 in SH, and I've got a PNG image. I copied it, but there is no paste function when I try to attach it here. (Win 7)

[robysue]

You need to upload the png image to a photo sharing site like Photbucket and then make the link from there. The url for the image needs to be between an [img] and an [/img] command.

[2bitwise]

So the only attachments can be a url.
That ties it.