Resmed S9 and Resperonics System One

I have been using my auto cpap for about 6 years now. I have a Resmed S9 and a Resperonics System One. After much trial and error I have homed in on a minimum pressure setting of 6 and a maximum of 11 and no ramp. I use a Dreamwear Nasal Mask.

My AHI results with the S9 are consistently better than with the System One. With the S9 I am routinely between 0 and 2. With System 1 my AHI is between 3 and 5, more variable and with occasional spikes of 7-10. I sleep about the same with either machine. Both machines report a 90% pressure of about 10.

I have been tracking this for about a year now and I am confident that the different results are independent of location and other factors.

Has anyone else experienced this? Does anyone have a possible explanation?

Don't really know, could be the calibration is different on each machine. Go for the gold, use the S9...

The algorithms for auto adjusting mode are different with the 2 brands. So how they go about doing their job is a little differently.
The ResMed is a bit quicker on the response time.
What you describe is common and I have seen it with myself. I have used both brands and with the Respironics I have to use a slightly higher minimum pressure than I do with the ResMed to get approx the same results.

MarcoSil wrote:I have been using my auto cpap for about 6 years now. I have a Resmed S9 and a Resperonics System One. After much trial and error I have homed in on a minimum pressure setting of 6 and a maximum of 11 and no ramp. I use a Dreamwear Nasal Mask.

My AHI results with the S9 are consistently better than with the System One. With the S9 I am routinely between 0 and 2. With System 1 my AHI is between 3 and 5, more variable and with occasional spikes of 7-10. I sleep about the same with either machine. Both machines report a 90% pressure of about 10.

I have been tracking this for about a year now and I am confident that the different results are independent of location and other factors.

Has anyone else experienced this? Does anyone have a possible explanation?

You need higher minimum pressure on the respironics because it's not as responsive to breathing anomalies as the resmed is.

Thanks Pugsy and Palerider. Makes a lot of sense.

My current minimum setting is 6 and max is 11. If I close this gap up much more I start asking myself why I wouldn't turn off the auto feature and just use it in regular cpap mode with a setting of 10 or 11. Another way of saying this is it looks like Resmed's auto adjust system is better than Resperonic's.

ResMed is a bit more aggressive/responsive but that isn't always a good thing for some people. Some people actually prefer the gentler way of doing things that Respironics seems to go about doing.
That said...most people would do well with either and it's perfectly fine for one person to prefer one brand over another brand for whatever reason they may have.
Most people don't get a chance to actually use and compare both brands.
I do know a small handful of people who have tried both and prefer Respironics...of course it's a small handful compared to the large handful that prefer the ResMed.

You might not need to increase that minimum all that much to get the same results with the Respironics but AHI numbers are just numbers and don't really mean much as long as you are sleeping good and feeling good. Maybe as little as 0.5 to 1.0 cm more.
I get better "numbers" with the ResMed but my sleep and how I feel is pretty much the same no matter what the numbers are and no matter what machine brand I am using.
I used a Respironics APAP for probably 4 years before I starting trying various machines. In fact I still have a PR S1 BiPap Auto that is my travel machine.
Now if I noticed a difference in sleep quality or how I felt during the day then I might do a little more tweaking with the Respironics but I don't so I don't really put much thought in minor differences in AHI.
It's not like I see AHI of 1.0 with the ResMed and 7.5 with the Respironics.
It's usually just maybe a 1.0 to 2.0 difference.

I will say this...it is nice to be able to use a little less pressure with the ResMed. Not that I ever had any real problems with the pressure I needed on the Respironics....it's just less is simply a bit more comfortable and I am all about comfort.

Thanks again Pugsy and palerider.

I increased the minimum pressure on the Respironics to 8 (max 11) and turned off the ramp. Better numbers and probably a bit better sleep. At some point I may just disable the auto mode and set the pressure at my 90% pressure (9-10) and see what happens.

MarcoSil wrote:Thanks again Pugsy and palerider.

I increased the minimum pressure on the Respironics to 8 (max 11) and turned off the ramp. Better numbers and probably a bit better sleep. At some point I may just disable the auto mode and set the pressure at my 90% pressure (9-10) and see what happens.

Anybody that tells you there's some important significance to the 90-95% pressure is someone that doesn't understand cpap.

That pressure is just a 'max pressure' that throws out any short term spikes.... much like in the olympics where the highest and lowest scores are tossed out. It's not a relevant number for determining best pressures.

OK, so for the past 2 months I have been experimenting with settings on my Respironics machine and find that the tighter the range, the better the numbers. I homed in on a min of 8 and a max of 10, no ramp and Aflex of 2. This got my average AHI down to about 3 with almost all being hypopnea. Previously, on this machine, I was running an average AHI of about 5 with a min pressure of 4 and a max pressure of 11.

So, I decided to try running on straight CPAP mode for a while. At a CPAP setting of 9 with Cflex+ of 2 my average AHI is a little under 2. Quality of sleep seems about the same, maybe a little better since there are no large pressure swings in CPAP mode. This is about the same result I get from my S9 in auto mode with pressure range set 4-12.

I'll be using CPAP mode when using the Respironics machine and the auto mode when using my S9.

I have a question if you can help about the S9. I just started using this system last week and I'm so confused. Do I just push the button and it starts? And why is the light staying red over the water area? I thought it was suppose to be blue? Nobody I know have a machine like mine so I don't know who to ask. I tried contacting my doctor but being I have an older machine its like they are trying to push me to buy a newer one.