cake321 wrote:I had been using an old F&P HC234 for about a year, but wasn't getting any good results from my CPAP therapy, so I ponied up and bought a Resmed S9 Autoset. I was originally prescribed a setting of 11 last year. I set my range last night for 8-20. I always thought the setting they originally told me (11) wasn't right. I know one night of data isn't much, but what does it look like based on one night? I'm trying to learn what all of these things mean. I've attached my results below.
What is the difference in "Mask Pressure" and "Pressure"? Which one is the setting that the machine was set to?
Also, I think the 95% Pressure is the important number, isn't it?
What the leaks numbers? Are they indicative of a leak?
I believe the 1.0 AHI is good, right? I don't feel all that much better, though.
Thanks a lot for any help. Like I said, I'm still learning how to interpret all of this, but I'd appreciate if anyone could help in the time being.
Well, first off, thanks for attaching your complete data. It makes it much easier to see what's what. There's a lot more data there than you really need. Minute ventilation, response rate, etc, aren't really necessary.
Pressure is pressure delivered at the end of the hose. And unless you have a rat's nest stuffed in your mask, then that pressure will also equal the mask pressure. Sleepyhead probably provides the two pressure charts because the pressure at the machine will always be higher than the pressure in the mask because of the resistance to flow the hose provides. But your S9 automatically compensates for that resistance and displays only one value, that being the pressure at the end of the hose. I'd delete one of the charts in the preferences.
The 95% pressure is the highest pressure that you were experiencing 95% of the time. It can be thought of as that pressure that would most likely would provide you with the best chance of treating any obstructive events, if you were setting your machine for constant pressure. But that number is affected by the amount of "hunting" the machine had to do in order to chase down obstructive events. More on that later.
Your leak numbers are low; I wouldn't worry about them. You're always going to have leaks. They come and go. If they last for a long time, then it's time to think about how to fix them (adjusting straps, etc).
1.0 AHI. There are people on this forum who would trade an arm for such a low AHI. Anything below 5 is considered good. 1.0 is very good. Low AHI doesn't automatically translate into feeling good. It just means that your machine is preventing obstructive events effectively. Feeling good doesn't automatically follow from having a low AHI. Sleep is a very complicated subject and having adequate oxygen is only a small chapter in that book.
Looking at your pressure chart, I think you could improve your therapy by setting your low pressure limit higher. Notice what's happening on your pressure chart. Every time the pressure comes down to about 9, an event happens (snores,mostly) that causes the machine to increase pressure. Then the machine slowly tapers the pressure down until another snore sets it off again. So your pressure trace looks like the Alps. Your machine is constantly hunting. If you raise your low pressure limit to 10 or 10.5 those snores will be reduced or eliminated and the pressure spikes won't be as frequent or as high, and your 95% pressure will be reduced. If everything is set right, and if your pressure from your titration study was done correctly, your 95% pressure should fall very close to that lab titration value. For example, like yours, my lab value was also 11.0, and my 95% pressure is always within 0.5 cm of that number, and I never see spikes over 13 cm. What you want to see is the pressure trace spending some time lying down against the lower pressure limit. If the lower pressure limit is consistently below the minimum pressure displayed on your pressure chart, then the low pressure limit is set too low.
From the pressure trace, I think the 11.0 pressure from your titration study is about right. If I were you, I'd set the minimum pressure at 10.5 and the max pressure at 20 and see how you do for one night. What you want to see is those sharp pressure spikes to become fewer and not so tall. BTW, there's no reason to set an upper pressure limit with your machine. Effective therapy is all about setting the lower pressure limit correctly. The machine will take care of the rest.
