S-9

[hrc54]

Hi all-

I'm now totally confused. I set my S-9 to 12 last night on CPAP. Using my Resmed Activa mask-I selected "nasal" mask setting on the Clinician's menu rather than the "pillow" selection when I use my Breeze mask.
My question concerns the Leak rate. It said "31.2 L/m". That's 31.2 liters per minute. I thought that was a very large leak but on the mask fit it had a smiling green face.

I'm totally confused now. I thought the Resmed machines S-8, S-9 reported the leak rate over & above the mask leak rate that you set on the machine. That is. once you select the mask then the leak rate on the Resmed machines that you see for reporting purposes are AFTER the machine compensates for the mask. Yet, the smiling green face was there & had good numbers.

Any insight??

Thanks-Bob

[jmelby]

What leak rate number are you reporting? If that is your Maximum leak rate, then your results make sense... having leak go up to a high rate a few times (due to adjusting your mask, etc) is not unusual, and would not impact the smiley face. If that is your 95% leak rate, then it's another story... as you state, 31.2 is a high leak rate and the machine is subtracting out expected ventilation. Are you looking at this in ResScan or on the machine?

[hrc54]

Thanks jmelby. I'm looking at it in the "information menu". I got that by holding down both buttons for 3 seconds. I don't have the Rescan software. The menu which starts with the icons goes through "sleep quality".
I have it in CPAP mode. The thing that confuses me is that the "mask fit" icon was a smiling green face.

I first looked at the leak rate & was shocked to see it was so high (31.2 liters per minute) considering the Resmed machines ALREADY compensate for the mask flow rate. I've already selected the "nasal" setting on the which mask I use. But, with that said, why the smiling green face??

Thanks-Bob

[jmelby]

I use the software so haven't really paid attention to the leak rate reported on the machine. My guess is that it is reporting the maximum leak for the night, not the 95% or median... thus your leak rate was fine most of the night... the amount of time with a high leak rate did not meet the threshold to mark your leak as bad (thus the smiling face instead of the frown). The best way to know for sure would be to check in ResScan and look at the graph for the night.

I wonder if anyone else knows whether the leak rate reported on the machine is the maximum leak or something else...

[KC5cychris]

you may want to look at the flow curve for you mask.
I use the quatrro and at 10, the l/m would be around 40
looking at this may help determine if yu are in the window
I use Resmed so haven't really paid much attention to what is on
the machine as far as numbers and the smile face other than mask fit

Chris

[KC5cychris]

double

[hrc54]

Thanks for the replies. I guess my question on that screen is does it already take into account the flow rate on the mask. Last night I used a Resmed Activa mask & selected the "nasal" setting. On a pressure of 12 cm the mask has a flow rate of 34 liters per minute. My leak rate was 31.2 liters per minute. So, if you add those together you get about 65 lpm. Very high. Of course, why did the "mask fit" say everything was fine?

Thanks-Bob

[DreamOn]

I believe that the Mask Fit icon (smiley/sad face) is only indicating the results from using the "Mask Fit" feature on the S9 machine (pressing the Push Dial and holding down for at least three seconds to test the mask fit). I don't think it's reporting the overall nightly leak rate.

Like the ResMed S8 machines, I believe the Leak Rate reported on the LCD's screen is the 95th centile value. On the S9 machines I believe that the mask's "intentional flow rate" is subtracted before the Leak Rate is reported, just as it is on the S8 machines. In theory then, if you have no leaks and have the correct Mask setting on the machine, the machine-reported Leak Rate should be zero. I believe that the "acceptable" leak rate threshold is the same for both the S8 and S9 machines. A leak rate above 0.4 liters per second (which is 24 liters per minute), could affect your comfort, therapy effectiveness, and accuracy of reported results (such as AHI).

I could be wrong about any/all of that, but that's the way I understand it. Your leak rate is indeed too high. Look for leaks from the mask cushion, air escaping from the mouth (perhaps when you're deep asleep), and check for holes in tubing and connectors. I hope that helps!

[Nord]

I believe that the Mask Fit icon (smiley/sad face) is only indicating the results from using the "Mask Fit" feature on the S9 machine (pressing the Push Dial and holding down for at least three seconds to test the mask fit). I don't think it's reporting the overall nightly leak rate.

Like the ResMed S8 machines, I believe the Leak Rate reported on the LCD's screen is the 95th centile value. On the S9 machines I believe that the mask's "intentional flow rate" is subtracted before the Leak Rate is reported, just as it is on the S8 machines. In theory then, if you have no leaks and have the correct Mask setting on the machine, the machine-reported Leak Rate should be zero. I believe that the "acceptable" leak rate threshold is the same for both the S8 and S9 machines. A leak rate above 0.4 liters per second (which is 24 liters per minute), could affect your comfort, therapy effectiveness, and accuracy of reported results (such as AHI).

I could be wrong about any/all of that, but that's the way I understand it. Your leak rate is indeed too high. Look for leaks from the mask cushion, air escaping from the mouth (perhaps when you're deep asleep), and check for holes in tubing and connectors. I hope that helps!

DreamOn is completely correct.
Beside the "smiley face" it says... Mask Fit ... not Leak.
Your Leak rate is very high for 95 percentile Leak and you should look for mouth leaks etc.

Nord