Understanding the report values

[Suresh555]

I recently found out i have sleep apnea and am trying a dreamsrstion machine and a resmed one to see which one to buy. I am very confused with the variance on the reports provided by both these machines. For example, the former gives out types of apnea in whole numbers and the later provides as decimals. Also resmed shows event kind different from phillips that has 3. Can someone please guide me to understand these numbers?
Thank you in advance

[LSAT]

AHI is the number of events per hour. An event is where you stop breathing for 10 seconds or more. The events are Apneas where there is an 80-100% blockage, Hypopnias where there is a 40-79% blockage and Centrals where there is no blockage. The total of all three types divided by the number of hours slept is the AHI.

[Pugsy]

Get OSCAR and see the real details.

What these machine reports on the LCD screens varies widely. Not to mention the criteria for classification varies slightly for hyponeas between the 2 brands.

OSCAR https://www.sleepfiles.com/OSCAR/
http://www.apneaboard.com/wiki/index.ph ... stallation
http://www.apneaboard.com/wiki/index.ph ... rpretation

[Julie]

But FWIW the Resmed Airsense 10 autoset (For her model especially) is far more popular than the Phillips (Dreamstation, etc).
Both use different algorithms which accounts for differences you are looking at.

[zonker]

For example, the former gives out types of apnea in whole numbers and the later provides as decimals.

welcome to the zoo!

it's those decimals that i believe saved me from aerophagia. you can lower or raise the pressure in the dreamstation by .5 increments. in the resmed, you can lower/raise by .2.

i was SO sensitive to aerophagia that even raising my pressure(to get more effective therapy) by the .5 was impossible for me. even the .2 of resmed was difficult, but doable.

yes, i've used both resperonics and resmed. for me, i'll take the resmed any day.

good luck!!

sorry, i just realized i answered a question you didn't ask!


i haven't seen an example of what you are talking about re: events. they both read the same to me.

[Suresh555]

Thank you all for responding, I surely will check out OSCAR
Here are the examples of my data from both systems that confused me
Two sets of examples from dreamstation

Total clear airway apnea
Day one 0
Day two 1

Total obstructive apnea
Day one 5
Dsy two  0

Total hypopneas
Day one 10
Day two  21

Two sets of examples from resmed .

Total AI
Day one 0.5
Dsy two 0.6

Central
Day one 0.2
Day two 0.1

See the different values? The clear airway and Central is the same, yet in dreamstation I see 0 and 1 yet in resmed I see 0.2 and 0.1
There is no obstructive or hypopnea in resmed?

[Pugsy]

You are missing a critical data point on the ResMed machine...
Index...hourly average
AHI....ResMed
which is the total of the Apnea index and the hyponea index
The Apnea index is a total of the central apneas and the obstructive apneas. The hyponea index is never really overtly shown on the LCD screen and we have to sort of figure it out doing backwards math.
Example....AHI of 3 and the AI is 2 (and it's made up of 1 central and 1 obstructive)...that leaves the Hyponea index also being 1
or here's another example....AHI of 8....and the AI is 5 (made up of 3 centrals and 2 obstructives)...so that means the Hyponea index was 3. You have to subtract the AI from the AHI to get the hyponea index.

Or just use OSCAR.

As for as the values being slightly different between the 2 brands...we don't sleep the same each night. It's going to vary quite a bit even if the machine brand is the same.
Not to mention that each brand does things a little differently anyway and it's like trying to compare an apple and an orange. They just are going to taste different.

You can combine both machine's data into one profile in OSCAR. I have 6 machines in one profile at the moment....maybe 7.

[Suresh555]

Thank you Puget, for explaining. It does make more sense now. I guess I was also confused because of difference of full numbers vs 0.x numbers for the same item in two different machines.

[Suresh555]

Sorry Pugsy, the auto correct messed up your user name

[Suresh555]

Ok , so going by my machine data, showing
AHI of 1.3
AI of 0.5
Central AI of 0.2

Are the following correct (using your formula)
Obstructive would be 0.3
Hypopnea would be 0.8

[Pugsy]

Ok , so going by my machine data, showing
AHI of 1.3
AI of 0.5
Central AI of 0.2

Are the following correct (using your formula)
Obstructive would be 0.3
Hypopnea would be 0.8

You got it.

I have used both brands over the years. In fact started my cpap therapy in 2009 on the Respironics and later tried the ResMed and liked it better. Respironics always seemed to show a little higher AHI than ResMed even long term.
Nightly variations are common because we just don't sleep the same each night but even long term and looking at trends the Respironics was always a little bit higher AHI. Not enough to really be a big deal but anywhere from 0.5 to 1.5 higher AHI.
There is a little bit of difference in flagging criteria for the 2 brands in terms of hyponeas but not a big difference.
I always wondered if their sensors were just a bit "more sensitive" which I know doesn't make much sense but years of using both brands gave me always a little bit higher overall average with Respironics. Never enough to be a deal breaker though so I finally shrugged my shoulders and moved on because it was something that was beyond my capabilities to figure out exactly why.

Don't worry about the auto correct....though you can go in an edit any post you make if you want to. See the little pencil on the upper right of the post reply box? That's the edit pencil...click on it and your post will open up and you can fix any typos.
I get Pugsy, Pugly, Pugsly, and others from time to time. To be honest, I didn't even notice until you mentioned it.


Now the Respironics machine only shows Apneas and hyponeas indexes. It won't breakdown the apneas into central (Respironics calls them clear airway) apneas or obstructive apneas. I don't have a cheat for it. Must use the software.
To be honest I hate Respironics LCD reporting because it's kind of important sometimes to know if the apneas are central or obstructive.

[Suresh555]

Again, thanks for sharing your knowledge and experiences. I am very new to this and started my first therapy on November 28th 2020. Dreamstation was the first machine offered to me and used it for 40 days. I have only used Resmed only or 4 days. Dreamstation now does break down all three type events (Obstructive,Clear and Hypopnea) in their Dreammapper app and the data is instantly reported through bluetooth. I was unimpressed by the MyAir, the app I was asked to use for Resmed and hopefully OSCAR will provide better reports. I do like the Resmed design better.

[Pugsy]

Yes, I know that you can get event category breakdown in the DreamMapper app but it is the total number of apneas and not the hourly index. One can of course easily figure out their own hourly index if they want to.

I did try DreamMapper back in the day but I found that the app on my computer was continually calling home without my wanting it to call home or when there was no need to call home. I don't like any app trying to call home unless I tell it to call home. Too much like spyware. Just me being OCD about stuff like that.....and if I want data from my machine I want more than the app will give anyway.
I did finally remove it but it wasn't easy...it left bits in the registry that still tried to call home after I uninstalled it. It doesn't cleanly uninstall either. I had to do some registry cleaning to get it totally out of my computer. I won't ever install it again even if I did try a Respironics machine again.

But I know people who love apps and love bluetooth and thinking that getting limited data on their phone or computer is enough for them...that's fine. If they are happy then I am happy but if they run into real trouble with their therapy and don't feel the good numbers (or they aren't getting good numbers) there's nothing on the MyAir or DreamMapper programs to really help figure out the problem and to fix any problem we first have to identify the problem.

[Suresh555]

How do one figure out hourly index from total apnea? Is hourly index more helpful and if so, how?

Most people i know except for one has resmed and are very happy with it.

I tried setting up OSCAR and got stuck at the part where it asked for the sd data. My machine does not have a SD card. Any idea how I can get OSCAR to read my data?

[Pugsy]

hourly index is nothing more than an hourly average.
Total number of apnea events (in whatever category) divided by hours of use.

You need a SD card to use OSCAR and if your machine doesn't have one then you need to get one and insert it in the machine.
The SD card MUST be inserted in the machine during use to get the detailed reports as they get directly written to the SD card while happening.
Only summary data is saved in the machine's internal memory.

Any generic SD card will work. You only need maybe 2 GB size but the small capacity cards are getting hard to find and actually can cost more. I got an 8 GB Sandisk SD card at WalMart and it works just fine.
You might have an old SD card laying around somewhere that might work....if not any place that sells the cheap cards will work.
Don't go getting one of the really big fancy SD cards like 64 GB...not needed, pricey and some people have actually had problems with their machines being able to handle them.