Leakage Rates too Low

Kairosgrammy wrote:You need to be cautious. You may be acquiring high rates of CO2. Other than that, I really haven't a bit of advice to offer. Just sounds hinky to me.

There is nothing to be hinky about. ResMed machines report leaks differently than Respironics machines.
It is quite common to have a 0.0 leak number for a ResMed machine. All it means is that there really isn't any excess leak above the vent rate..We just never see the vent rate reported on a ResMed machine.
ResMed removes the vent rate BEFORE it ever reports the leak to be shown on the machine or the software.

ResMed leak numbers and Respironics leak numbers cannot be compared as apples to apples because they are 2 different reporting values. ResMed being only excess leak being reported and Respironics being Total Leak being reported (Total leak being ..excess leak plus vent rate)

OP here is trying to subtract the vent rate from the ResMed reported leak and it is already been subtracted prior to reporting. We can't remove it twice.

Pugsy - well this answers my question I posted earlier (continuation of a thread)....but what is considered an acceptable leak rate for a ResMed? I have had "0" for 3 nights and a "1" last night. Just curious, I know I'm still good just want to know for the future.

Pugsy,

It still doesn't compute unless the ResMed subtracts more than 24. From the graph, the exhaust port should leak 36l/min, the ResMed machine would subtract 24, and the baseline leakage I should always get REPORTED BY THE MACHINE OR SOFTWARE should be at least 12l/min. Anything above 12l/min would be my mask leakage.

Unless you are saying that the ResMed machine would subtract 24 + up to an additional 24

charlestek wrote:Unless you are saying that the ResMed machine would subtract 24 + up to an additional 24

We don't know what Resmed uses as the generic number that it subtracts before it reports the leak.
We aren't ever told exactly how they come up with their figure.
Logic tells us that when someone chooses full face mask....that the machine has a set figure that it automatically will adjust upward as the average pressure goes up and thus the vent rate goes up. We never see that number. You are assuming that they use a 24 L/min number but we don't know what they use. That 24 L/min number is only the line where ResMed says all bets are off when the excess leaks gets above that number. My guess is that the actual number subtracted will be very close to an average of all full face masks at a certain pressure and will go up as the pressure goes up. I would bet money that it is well above 24 L/min. You've got your mind wrapped around the 24 L/min number as being related to vent rate and it is not.

If you just have to factor in your vent rate to your numbers...you will have to add the vent rate to what ResMed is reporting so that you have a total leak....and you will have to adjust the red line 24 L/min upwards by your vent rate.. Way too much work to end up with same result. Either that or get a machine like mine then you will see vent rate reported as well as excess leak.

Again...that 24 L/min is only a line in the sand...it isn't added or subtracted to anything at this point.

kwcrnp wrote:Pugsy - well this answers my question I posted earlier (continuation of a thread)....but what is considered an acceptable leak rate for a ResMed? I have had "0" for 3 nights and a "1" last night. Just curious, I know I'm still good just want to know for the future.

Answered in your thread but will answer here also.
ResMed says they can handle leaks up to 24 L/min. Your reported leaks are well under that line and you are fine.