How do I calculate AHI for PB 420E?

Adrian · Post by **Adrian** » Tue Apr 24, 2007 3:30 pm

It seems (almost) everybody has Remstar machines that show a figure for AHI. As the Silverlining software for PB 420 E only gives separate indexes, how should one calculate AHI to be comparable with Encore figures ?
Do I only add indexes for Apneas and Hypopneas or should I also add (indexes of) Apneas/CA and Hypopneas (FL)?

Adrian

Snoredog · Post by **Snoredog** » Tue Apr 24, 2007 5:21 pm

after downloading Compliance, click on Synthesis, should give you that info in the upper right of the page under EVENTS: and should give you the index/h. If you add up the apnea count and hypopnea count you have AHI. It gives you the information individually.

Single click on the "date" on the left and it will give you the AHI for that day only. Or

You can also double-click on the day used on the left and it will pop-up with the pressure details for that night.

By clicking ? and your machine type on the tool bar should give you the manual to the software which explains everything.

On the detailed page, that will give you a time-line of the last 95hrs in detail, clicking on the Magnification button it will expand out the graph, you can use the cross-hair pointer + and move to a particular apnea event and it will show you precisely when that event occurred.

TXKajun · Post by **TXKajun** » Wed Apr 25, 2007 10:35 am

Short answer, "Yep, just add the AI and HI numbers."

Kajun

xface · Post by **xface** » Wed Apr 25, 2007 11:13 am

Just curious... is there a way to see average apnea time and total apnea time for a night?

Snoredog · Post by **Snoredog** » Wed Apr 25, 2007 12:33 pm

xface wrote:Just curious... is there a way to see average apnea time and total apnea time for a night?

No, it doesn't report that information.

But it gives a good breakdown of apnea information along with the time-line of events seen during the night on the Detailed report which are probably the best you'll find in any machine's report.

This is the graph I like, my comments shown in green:

Adrian · Post by **Adrian** » Wed Apr 25, 2007 3:09 pm

Thank you very much for the replies.

Snoredog, could I ask you some questions:
1. Why do you keep the upper pressure so high (16) when the APAP barely reaches 7? Is the pressure graph real, as mine is much more linear (if an event happens it goes to maximum stays there for some long time, goes down to minimum and then goes back on - settings are 5-9).
2. Some cycle states are marked Not so good. Why is that so? I have an average of about 30% Flow limited Cycle. Is that wrong. Is that maybe related to my nasal obstruction (deviated septum + enlarged turbinates)?
3. Do you erase data regularly as your graph only goes to session 30, while mine is already at 95? If you erase the memory can you still add the back data to have a synthesis for a longer period?

Adrian

Snoredog · Post by **Snoredog** » Wed Apr 25, 2007 10:40 pm

[quote="Adrian"]Thank you very much for the replies.

Snoredog, could I ask you some questions:
1. Why do you keep the upper pressure so high (16) when the APAP barely reaches 7? Is the pressure graph real, as mine is much more linear (if an event happens it goes to maximum stays there for some long time, goes down to minimum and then goes back on - settings are 5-9).
2. Some cycle states are marked Not so good. Why is that so? I have an average of about 30% Flow limited Cycle. Is that wrong. Is that maybe related to my nasal obstruction (deviated septum + enlarged turbinates)?
3. Do you erase data regularly as your graph only goes to session 30, while mine is already at 95? If you erase the memory can you still add the back data to have a synthesis for a longer period?

Adrian