EncoreViewer Printout of Leaks

I would appreciate some help understanding the Leak portion of the Daily Details report. 1. What does LPM stand for?
2. My average leak is 18.00. What does the 18 represent? 3. I assume this is a good (low) leak rate?
4. My leak rate has a baseline line of about 18 which I believe is a standard rate for my low pressure setting of 4.5 and I understand when the graph line goes up, that represents a leak. What is happening when the line goes below the baseline, which mine does frequently througout the night? Thanks for the help.

valcherry wrote:I would appreciate some help understanding the Leak portion of the Daily Details report. 1. What does LPM stand for?
2. My average leak is 18.00. What does the 18 represent? 3. I assume this is a good (low) leak rate?
4. My leak rate has a baseline line of about 18 which I believe is a standard rate for my low pressure setting of 4.5 and I understand when the graph line goes up, that represents a leak. What is happening when the line goes below the baseline, which mine does frequently througout the night? Thanks for the help.

1. LPM is liters per minute.
2. A leak rate of 18.0 liters/minute with your comfortlite mask and a pressure of 4.5 indicates you are probably not leaking more than the designed exhaust rate for the mask. The mask must leak some air to avoid re-breathing respired air. Your pressure is off-the-chart low. The CPAP Mask Leak Rate Chart http://www.internetage.com/cpapinfo/leak-rates-1.html gives expected leak rates for different equipment and pressure settings. The lowest CPAP pressure is 8.0 cm H2O (centimeters water column), and for your mask the nominal leak rate is 23 LPM.
3. Its a very good leak rate, but very low pressure.
4. You may be blocking the exhalation vent with bedding or a pillow.

A 4.5 pressure setting is extremely low, and while it may support your airway, most of us feel "starved" for air at that setting because it isn't delivered fast enough to meet our volume requirements. Just be aware of how you feel, and it wouldn't surprise me if you increased that flow rate. How is your AHI at that setting?

valcherry wrote:I would appreciate some help understanding the Leak portion of the Daily Details report. ...

I assume this is from Encore View (or Encore Pro).

valcherry wrote:... 1. What does LPM stand for? ...

Let me quote from the online help:

Leak

Leak (in liters per minute). The dates of therapy are displayed along the bottom of the graph.

Displays the average leak rate per night of use. If the chart shows leakage at the “LL” level (large leak), this is an excessive leak that will compromise therapy. This could be the result of a poor mask fitting.

Note: The average, displayed to the right of the graph, is calculated by adding the daily averages and dividing by the number of therapy hours.

So, LPM is liters per minute.

valcherry wrote:... 2. My average leak is 18.00. What does the 18 represent? ...

I understand it should be 30 or less.

valcherry wrote:... 3. I assume this is a good (low) leak rate? ...

Yup. It is about 1/2 of the recommended maximum.

valcherry wrote:... 4. My leak rate has a baseline line of about 18 which I believe is a standard rate for my low pressure setting of 4.5 and I understand when the graph line goes up, that represents a leak. What is happening when the line goes below the baseline, which mine does frequently througout the night? Thanks for the help. ...

Not sure. My EncoreViewer reports don't look like that. No doubt others will be able to help here.

I'll see if I can help.


1. LPM stans for liters per minute which is the volume of air comming out the exaust holes in your mask plus any leaks.

2. 18 liters per minute (again volume of air) On Respirionics machines you have to subtract the design exaust rate for your mask to remove carbon dioxide and you should get the amout of leaks. 18 sounds good but I don't look at a pressure that low very much. It is hard to imagine that 4.5 cm/h20 would be enough to breathe.

3. If 18 is the design exaust rate then it is very good because you have 0 leaks.

4. If your leak line dips below the normal line it is generally means that you rolled over and stopped up one of the exaust hols on your pillow or something. This is not very good because if it is restricted you may be rebreathing some of the carbon dioxide.

Jerry

Welcome to the message board, Valcherry.

Your equipment profile indicates you have an autopap. Is the 4.5 pressure you mentioned the "minimum" pressure setting? If so, what is the maximum pressure set at? Or are you using the autopap in "CPAP mode" at one straight pressure of 4.5?

I agree with sleeprider here:

sleeprider wrote:A 4.5 pressure setting is extremely low, and while it may support your airway, most of us feel "starved" for air at that setting

If 4.5 feels ok to you...doesn't feel "stuffy" and doesn't feel like you want to suck more air, then that's fine for you. I'd want another cm or two as the minimum pressure myself, but everyone's different.

sleeprider wrote:How is your AHI at that setting?

Good question. If your AHI is usually 5.0 or below with a Respironics machine, that's good. I'd personally want my AHI to be below 3.0, but that's just my preference. But if you usually are seeing an AHI of 5.0 or more with a Respironics machine, I'd suspect that a minimum pressure as low as 4.anything cm H2O in auto mode needs to be raised. Or if that 4.5 cm H2O is a single fixed pressure in CPAP mode, it needs to be raised. Just my non-medical opinion.

The others covered leak rate already. I'd add only that the leak rate is not "exact"... I wouldn't worry about it varying some below or above your usual rate which is nice and low from what you reported. I regard the leak rate as just a rough approximation of what's going on leak-wise. If the overall rate seems nice and low, that's good enough for me. I don't worry about an occasional spike or a few reasonable plateaus in the leak rate.

My auto machine is set to run from 4.5 to 9.5.
My EncoreViewer numbers for the last two nights are:
#1 AHI 1.6, average pressure 4.7, over 90% pressure 5.7, average leak 21
#2 AHI 2.6, average pressure 5.4, over 90% pressure 7.3, average leak 22

And, I have to tape my mouth shut to keep air from bubbling out and waking me up. Sometimes, I end up having to put a strap (stretchy sock pinned together) around my head to keep my checks from puffing up and waking me up.

Again, thanks for the help.

Everything looks right from the numbers. AHI is controlled, pressure seems appropriate for you, and leaks are appropriate for the pressures and equipment in use. If you don't naturally block air from entering your mouth, you should talk to your DME about a full-face and see if that increases your comfort. Leaking into the mouth is a common problem for certain people, and while taping can prevent the air from escaping, its still not comfortable or natural. A full-face equalizes that pressure and if you can tolerate the greater coverage, may be more comfortable.

Sleeprider wrote:Leaking into the mouth is a common problem for certain people, and while taping can prevent the air from escaping, its still not comfortable or natural.

Taping the mouth and wearing a chinstrap around my face is very comfortable for me, compared to every Full Face mask I've ever tried (just about all of them, including the "hybrid" types.) So, it really is an individual thing, as to what feels "comfortable" or "natural."

Trying to sleep with ANY mask on one's face is not exactly the most natural or comfortable way to sleep, when it comes right down to it.

Sleeprider wrote:A full-face equalizes that pressure and if you can tolerate the greater coverage, may be more comfortable.

Yes, a full face mask may very well be more comfortable for Val, and for many other people. Wasn't for me -- I sleep much more comfortably with tape, chinstrap, and my favorite nasal pillows mask, but everyone's different. Several full face masks are well worth a try, of course.