Which numbers do I watch ... and what do they mean?

I could just leave it at that, but if you know me, you know I'm much more verbose (`plaws -v`). I have the S8 Elite and, thanks to various threads here, know how to access the stats (not that the DME, sleep lab, or doctor's staff mentioned any of this). What I need to know is what numbers to watch and what are "good" values.

Yours in wakefulness,

Peter

PS: I seem to get less bloating on my back (I'm normally a side/stomach sleeper) and even managed 8 hours of CPAP time last night - a new record for me in my first week.

I'm sure that some of the folks that are a lot more knowledgeable than me can fill in the gaps but the numbers I watch are:

1. AHI number, try to keep it under 5. Kinda watch the correlation between the OA (Apneas) and the H (Hypotonias)
2. Average leak data. Should be close to the specifications on the mask exaust port for the mask you are using. Tells you if you are leaking while you sleep.
3. Large leak data. Tells me wheather I am leaking a lot or taking my mask off at night.

I usually don't pay any attention to the snore index because it is not really important to my health.

Anonymous wrote:1. AHI number, try to keep it under 5. Kinda watch the correlation between the OA (Apneas) and the H (Hypotonias)

OK, mine's kind of high as I continue to experiment.

Anonymous wrote:2. Average leak data. Should be close to the specifications on the mask exaust port for the mask you are using. Tells you if you are leaking while you sleep.
3. Large leak data. Tells me wheather I am leaking a lot or taking my mask off at night.

Leak data, eh? Mine seems to be zero all the time, which can't really be right. Is this something I have to enable?

You have to first understand what is being displayed:

1. AI=Apnea Indice or Index, number of apnea per hour (avg.)
2. HI=Hypopnea Indice or Index, number of hypopnea per hour (avg.)

3. AHI=AI+HI (sum of above divided by 60 for avg per hour).
4. Leak=Leak can impact your therapy as pressure is lost via the leak, so to know if a pressure is working, you have to look at the leak rate. If you have selected the proper mask from the machine's menu it should rate that leak in the ***** rating (see your manual).

When trying to improve your therapy, you need to control leak so you know the data you are looking at is accurate, too high a leak rate machine will stop responding and data you are looking at then becomes be skewed.

First goal should be to get your Apnea indice (AI) below a value of 5 per hour or what is considered "Normal" or what a patient without OSA would have.

Apnea is a more severe event since it is a complete obstruction of the airway and results in the greatest drop in oxygen levels. So you always want to eliminate those first.

Once you get the AI to drop below 5 the HI should automatically begin to follow that trend although HI can increase and decrease as that AI number falls.

That number may even increase before it drops, but usually when it does that you have over-titrated yourself. What you are looking for is a "dip" or sweet spot with the pressures used as shown in the sample graph:



In the sample, if your current pressure is 7 cm and your AHI score is >5, then you need to gradually increase pressure (never more than 1cm per night) and observe the AI indice. That indice should fall (don't worry about the HI, ignore it), you only address HI once you get AI down to 1 or sub 1 avg. As soon as you get the Apnea count to its lowest HI should begin to fall, once HI starts to fall and gets below 5 you know you have done everything to get AI at its lowest.

This sample graph gives you an example, you will notice that 9.0 cm is that "dip" or sweet spot you are looking for. Obtain that and you will have achieved your ideal therapy pressure based upon the AHI finding. But keep in mind that lowest AHI finding doesn't always mean you will sleep the best at that pressure. In a lab they can see via EEG where you are sleeping the most peaceful which should in theory result in the lowest AHI (what you are trying to achieve).

So with that machine even you can plot your indices every day and write down your score, a weekly or 7-day average is going to give you a better picture than a single night.

plaws wrote:Leak data, eh? Mine seems to be zero all the time, which can't really be right. Is this something I have to enable?

Yes, that can be right. If showing your overnight stats (AHI, AI, HI) is enabled, showing you the leak rate is already enabled, too.

That brings me to a question --
My AI numbers were generally below 1 but my HI numbers were above 10 (in general). With an AHI of 11.7 but the AI numbers below 1 was I premature in assuming that my treatment wasn't working??? How long does it take for the HI numbers to come into check with the AI numbers??
My leak rate is usually about 25 which is about what the mask should be venting.....

Sounds like you've got the info wired plaws!!! Let us know how you're doing!!!
I may have gotten to "into the numbers" in looking at mine - hence the question above.....

good luck
cheers
goose

goose wrote:Sounds like you've got the info wired plaws!!! Let us know how you're doing!!!

Well, I don't know about that. I have been keeping notes since, though, and trying to note anomalies (like when I forget the decongestant or forget to top up the humidifier).

The one thing about my numbers that really stick out are how all over the place they are. Some nights AHI is around 10, other nights around 6. And the AI and HI are all over the place too.

As far as hours, what are most folks getting? My have been creeping up and I've had several nights, especially if I get to bed before 2200, where I get over 8 hours of Magical Box Sleep.

I've found, too, that if I kick the mask off around 0500 and then go back to sleep (mostly on weekends) that I may "sleep" another hour or 2 or 3, but I sure don't feel rested. Think I'll just start getting up when I can't stand the mask any more.