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+--- Thread: Calculating AHI on Resmed (/Thread-Calculating-AHI-on-Resmed)
Calculating AHI on Resmed - theMezz - 07-30-2018
How does the ResMed calculate AHI?
Does it include awake time?
If I have 100 actual events in 4 hours - that's an AHI of 25
BUT
If I have the same 100 actual events in 4 hours
and have the machine on me for 5 hours and get 4 hours of sleep
is my AHI still 25 or does it calculate to 20?
If wake time is counted as sleep time, then AHI can be potentially misleading (?)
RE: Calculating AHI on Resmed - mesenteria - 07-30-2018
It includes the total measuring time by the machine (when it either senses you are using it and turns itself on, or when you first turn it on) and when the 'session' is either interrupted or ends. Meanwhile, assuming you are wearing a suitable mask with correct fit, it will record all hypopneas and OA/CA. It does a simple averaging over hours/portions thereof use.
RE: Calculating AHI on Resmed - Stom - 07-30-2018
(07-30-2018, 10:36 AM)theMezz Wrote: If I have the same 100 actual events in 4 hours
and have the machine on me for 5 hours and get 4 hours of sleep
is my AHI still 25 or does it calculate to 20?
If wake time is counted as sleep time, then AHI can be potentially misleading (?)
Yes, the ResMed just gives you a mathematical average, based on how long the machine was on. It doesn't try to estimate sleep vs awake time. It's not a sleep study.
If you know when you were awake (and you can often estimate this from your flow graphs in Sleepyhead) you can manually subtract your awake events from your score. This is one of the advantages of using Sleepyhead and looking at the details rather than the summary data on the machine or in AirView.
RE: Calculating AHI on Resmed - sonicboom - 07-30-2018
Your machine has no way of detecting when you are awake or asleep. You can do a manual calculation by subtracting your awake time.
RE: Calculating AHI on Resmed - sheepless - 07-30-2018
I suffer from fragmented sleep (maybe called sleep maintenance insomnia?) so if sufficiently awake I make it a habit to turn off the machine, forcing me to remove the mask, to avoid seriously skewing the reported data. then restart everything when I decide I can go back to sleep. if I don't fall back asleep within a few minutes, I stop the machine again to limit the skew.
RE: Calculating AHI on Resmed - theMezz - 07-30-2018
thanks, everyone
that's good information