S8 to S9

I had read on here that the S8 was bad about showing HypoApnea's. I've had the S9 for a few days and haven't had a single one with the S9. I will say I like the S9 better and the EPR seems to work better. I like having the flow data as well.


The S9


The S8

I've seen the posts about the s8 scoring hypopneas aggressively as well. But, I don't get it. If there is a clearly defined formula that it uses to determine one that is pretty much the same as the s9 or even a respironics machine how can this be?

My question is this: does the s9 do a better job of catching/preventing hypopneas?

I've got almost 5 years in on an s8 elite, and am getting an s9 autoset Monday. Since my ahi lately is usually about 5 - 6 on the s8, and it's almost always about 90% HI I will be anxious to see Tuesday's numbers!

This thread talks about the algorithm change with the S9: viewtopic/t50229/S9-AHI-accuracy.html

There seems to be consensus that the S9 algorithm scores hypopneas less aggressively on purpose, to bring it more in line with other brands. I've used an S8 and my AHI was higher than on the S9, and the score was mostly hypopneas. Ditto for the S7 platform, which may have used the same algorithm.

I recently made the switch from S8 AutoSet II to S9 Auto. After almost 4 wks, I have found:

1. leaks and pressure - no significant change.
2. Hi go from 5-9 range to less than 1
3. Ai drop from 3-4 range to under 1.
4. What now appears are centrals, which the S8 could not pick up on the data card - in the 2-3 range

Overall my total AHI numbers have dropped. Do I feel any different? No!

S8 = AHI 1-5
S9 = AHI 0
PR ONE Series 60 AHI 0.4-3

RandyJ wrote:This thread talks about the algorithm change with the S9: viewtopic/t50229/S9-AHI-accuracy.html

There seems to be consensus that the S9 algorithm scores hypopneas less aggressively on purpose, to bring it more in line with other brands. I've used an S8 and my AHI was higher than on the S9, and the score was mostly hypopneas. Ditto for the S7 platform, which may have used the same algorithm.

Yes, I've seen lots of threads that talked about this. I was suprized when the S9 hasn't shown any HI's at all. The S8 was almost all HI's.

Over all I feel the S9 is a big improvement. I really like the climate line hose and the humidity settings. I have the dishwasher safe S8 tank but the S9 version is much easier to clean. The only thing I don't like is (like most people) the hose comes out the back.