What is Normal Average Leak Rate?

[Lanco]

I am trying to figure out if my leak rate is ok as compared to all the other data I'm getting. I have an Apex XT Auto and use an Apex Wizard 210 nasal mask. I am using Apex Easy Compliance software. What I am showing is the average for 22 days.

Average AHI: 2.27
Average Pressure: 8.2
Average 90th Percentile Pressure: 8.9
Average Leaks: 51.8
Average Time with Large Leak: 1.81 Minutes

My mask exhaust flow is about 24 L/minute at pressure 8.

If you subtract 24 l/m from 51.8 you come up with 27.8. I am not sure if this is how to figure this out or not but I have seen mentioned in different places that if your Average Leak Rate is around 25 you're ok.

Can anyone verify this and explain this so I know i'm getting proper therapy?

Thanx

[justMongo]

Sorry this answer is not very helpful. So few people use that machine, that finding someone who knows the tolerance for leaks is going to be a long shot. This is one where you might try searching online for info about that machine; and see if you can dig up its specs.

[Lanco]

It seems to me someone that knows how the stats that I gave work together should be able to tell me what is right regardless of what brand cpap or mask. Or am I wrong with that assumption?

[justMongo]

I believe the assumption is wrong. The ability of the blower to maintain pressure against a specific flow varies by manufacturer.
24 LPM of unintentional leak is considered the max leak in ResMed machines. One cannot carry that over to the APEX XT Fit.
It's sort of a question of reserve capacity; and that's not guaranteed across manufacturers. APEX XT Fit is a rather small unit; and I would not be surprised to find it has less reserve capacity.

[Lanco]

Below is what my respiratory therapist said when I questioned all the leaks. Average being around 50 l/m Highest Leak being 74 and Lowest Leak being 7:

"If your total AHI is 2.23 then that is acceptable. I wouldn't overthink this too much. Regardless of the leak, if your AHI is that low, then you are good. Textbook normal is less than 5."

I am only a bit insecure about this because the original data I sent him showed a low AHI like around 1.75 at that time but leak rate similar to what I have listed here. Following that he is telling me to get a chin strap and then maybe a full face mask.

Then he told me that all was ok after resubmitting the newer info. I assume he missed the AHI number in the first correspondence and then corrected, but not sure and am a bit insecure because of how this played out.

Comments?

[green wings]

I agree with Mongo about not knowing what the acceptable leak rate for your machine is.

I think, though, that the stat "Average Time with Large Leak: 1.81 Minutes" (per night, I think?) tells you that your machine is saying that you're having very little time spent with a leak rate above the threshold that your machine can handle.

I am trying to figure out if my leak rate is ok as compared to all the other data I'm getting. I have an Apex XT Auto and use an Apex Wizard 210 nasal mask. I am using Apex Easy Compliance software. What I am showing is the average for 22 days.

Average AHI: 2.27
Average Pressure: 8.2
Average 90th Percentile Pressure: 8.9
Average Leaks: 51.8
Average Time with Large Leak: 1.81 Minutes

My mask exhaust flow is about 24 L/minute at pressure 8.

If you subtract 24 l/m from 51.8 you come up with 27.8. I am not sure if this is how to figure this out or not but I have seen mentioned in different places that if your Average Leak Rate is around 25 you're ok.

Can anyone verify this and explain this so I know i'm getting proper therapy?

Thanx

[green wings]

I've only been using CPAP since last winter. I used a nasal mask for the first four months, though. When it would leak, it was generally at the area that touched the bridge of my nose. At first, I would find that the sound of air hissing would wake me up. I'm pretty sure I started adjusting the mask in my sleep after a few weeks.

One thing I would see with the nasal mask was that, for me, a nasal cushion was only good for about six weeks. After that, it would start leaking enough to wake me up frequently. So you might want to keep an eye on the leak values to see if they increase with time. How long a nasal cushion lasts seems to vary greatly from person to person.

The other thing that you don't want, of course, is to lose your "tongue seal" and let pressurized air start escaping from your mouth. That may be happening during the short periods of time that are being recorded as "Large Leak".

Another thing that can happen is what people on the Apnea Board Forum usually call "lip leaking". This is when puffs of air escape from your lips. If it happens while you're awake, it will feel really weird. It's like fish lips. Lip leaking happens when you lose the "tongue seal" partially.

I don't know if any of this info. is at all helpful to you. If you are feeling better from using your CPAP machine, and you're not waking up with a very dry mouth, and the % of time in large leak stays low, you can just not worry about it.

Or you can try a chin strap or a full face mask. (The other way to go would be to try nasal pillows - those don't leak much at the interface with the nose. If leaks show up with them, you can be pretty sure they're coming from the mouth.)

Below is what my respiratory therapist said when I questioned all the leaks. Average being around 50 l/m Highest Leak being 74 and Lowest Leak being 7:

"If your total AHI is 2.23 then that is acceptable. I wouldn't overthink this too much. Regardless of the leak, if your AHI is that low, then you are good. Textbook normal is less than 5."

I am only a bit insecure about this because the original data I sent him showed a low AHI like around 1.75 at that time but leak rate similar to what I have listed here. Following that he is telling me to get a chin strap and then maybe a full face mask.

Then he told me that all was ok after resubmitting the newer info. I assume he missed the AHI number in the first correspondence and then corrected, but not sure and am a bit insecure because of how this played out.

Comments?

[Lanco]

Perhaps this will help:

[green wings]

Can you do a one-day report for 8/4? I see places where the leak graph for that day drop to zero, but I can't tell if that happened because you turned the machine off. I'm still not entirely clear about whether the leak value your machine displays includes the mask vent. If it does, it should never be zero once the machine is up and running.

Thanks.

[Sleepster]

Below is what my respiratory therapist said when I questioned all the leaks. Average being around 50 l/m Highest Leak being 74 and Lowest Leak being 7:

"If your total AHI is 2.23 then that is acceptable. I wouldn't overthink this too much. Regardless of the leak, if your AHI is that low, then you are good. Textbook normal is less than 5."

I would not agree with that. You need to look at the leak rate graph for each night. If it goes up and down a lot, that means you're leaking. If you have a well-fitting nasal mask then it's likely the leaks are from your mouth. The remedy is a chin strap. If that doesn't work, a full face mask.