AirSense 10 "Sleep Report"

[SleepyTimeTime]

I'm having trouble understanding the "Sleep Report" screen on my ResMed AirSense 10. It shows the following (data in parentheses are value ranges for the last six nights):
1. Events per hour (2.0 to 14.5)
2. AHI (6.8 to 7.2)
3. Total AI (5.5 to 5.8)
4. Central AI (4.7 to 4.9)

OSCAR shows an "AHI" that matches the machine's Sleep Report value of "Events per Hour" so that looks like Obstructive + Central + Hypopnea but EXCLUDING RERA. But the machine on-screen specifically shows an AHI value that has a much narrower range than the "Events per Hour" value.

Can somebody shed meaning or a technical definition of the four values shown in the Sleep Report on the machine, why they do not use the same nomenclature as OSCAR, and specifically what are #2, #3, and #4? How does #2 AHI differ from #3 Total AI? What is "AI"? Is it an "Apnea Index"?

ResMed seems to be deviating from industry standard measurements and nomenclature after their "Events per Hour" measurement. Seems like this should be simple. There is nothing that I can find in the ResMed AirSense 10 manual defining the on-screen values being reported. In fact, the manual (I think) only discusses the "Events per hour" value and ignores the other three.

This is quite confusing.

Thanks in advance!

[Crimson Nape]

These values can be reported by the day, week, or month. Which do you have it set for?

[SleepyTimeTime]

Thanks for pointing that out. It took me forever to find out how to change the averaging period.

I found two versions of the manual online and only one points out the averaging period can be changed. Even then, the manual just barely suggests that the "Period" item on the menu is a clickable action item. Every other item under "Sleep Report" provides information only and is not clickable. Only the "Period" can be clicked to change a setting. That is terrible user interface design -- there should be some indicator showing that you can get to a submenu by clicking the word "Period." The manual could certainly be better in that regard, too. It says "Set the time interval covered by the sleep report"; it would have been better to say "Set the averaging period covered by the sleep report."

The tech who set up my machine set the reporting average period to "Month." I didn't realize that was an adjustable parameter until you told me nor did I realize I was on "Month" because I always scrolled right past that to get to the AHI data.

By changing it to "Day," the "Events per hour" value at the top of the Sleep Report now matches the "AHI" value at the bottom of the Sleep Report.

One further question. Last night I got these readings shown on Sleep Report on the machine:
AHI           5.2
Total AI      3.7
Central AI    2.4

Looking at OSCAR today, I see:
AHI           5.30
Obstructive   1.29
Hypopnea      1.58
Clear Airway  2.43 (same as "Central")

So, from this, I infer the following two things about the machine Sleep Report:
1. "Total AI" is Obstructive + Clear Airway (Central)
2. Hypopnea is NOT included in the Sleep Report

Is this correct?

I've been logging the CPAP machine "Sleep Report" data in my Excel spreadsheet, but it appears I don't have to do that because OSCAR provides the details I need and I can do my own moving averaging in Excel. That will save me some logging and analysis time.

[Crimson Nape]

Yes, you are correct. The values appear correct based on rounding. The Clear (2.43) and the Obstructive (1.29) add up to the AI (3.7) at the top. If you subtract the AI(3.7) value from the AHI(5.2) you get a value of 1.5. This is close to the Hypopnea of 1.58 listed at the bottom. AHI stands for Apnea+Hypopnea Index. Apneas are classified as either Obstructive or Clear/Central. Hypopnea is a reduction of breathing, so they are classified separately.

[harrywr2]

The tech who set up my machine set the reporting average period to "Month."

Actually the machine defaults back to 'Month' every time it's unplugged or there is a loss of power.

[SleepyTimeTime]

Thanks. I moved the machine to a different location and we've had some power failures. That explains why it is on "Monthly." I have no idea how it was set up in the beginning. I did not know it reverted to Monthly upon power failure and restart.

I'm going to stop using the on-screen Sleep Report as all the statistics are available via SD Card to OSCAR.

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Thanks. Glad to get confirmation on how they are calculating and presenting the data.

[Sleepster]

You can also use the myAir website to look at some of the statistics.

[SleepyTimeTime]

Thanks. I've looked at MyAir and all I see is the bare bones top-level stats (AHI, total time, leakage, overall score). Are there more detailed stats there?

[Sleepster]

Thanks. I've looked at MyAir and all I see is the bare bones top-level stats (AHI, total time, leakage, overall score). Are there more detailed stats there?

No, but I find that limited info useful and easy to access. When I want or need more detail I go to OSCAR or ResScan.

[SleepyBull]

I was confused by these numbers too.