If Mask Leaks, Why No Apneas?

[pat07011]

I've been using the Resmed Autoset Spirit with the Resmed Ultra Mirage FF mask. Efficacy Data varies for pressure each night, but is pretty near the same for the other readings.

The data for last night reads: Pressure-6.8, L/s-.30, AHI-2, AI-.3, HI- 1.7. Is that a high leak rate? And does AI of .3 mean that I'm having less than 1 apnea? How do you have less than 1 apnea? Perhaps I'm not getting something here.

As long as I'm having very little apneas, would it matter whether or not the mask was leaking?

[Wulfman]

I've been using the Resmed Autoset Spirit with the Resmed Ultra Mirage FF mask. Efficacy Data varies for pressure each night, but is pretty near the same for the other readings.

The data for last night reads: Pressure-6.8, L/s-.30, AHI-2, AI-.3, HI- 1.7. Is that a high leak rate? And does AI of .3 mean that I'm having less than 1 apnea? How do you have less than 1 apnea? Perhaps I'm not getting something here.

As long as I'm having very little apneas, would it matter whether or not the mask was leaking?

Those are per-hour statistics.
Yes.....leaks matter. (and may throw off the numbers)


Den

[DreamStalker]

If you have one apnea and slept for one hour, your AI will be 1.0 but if you slept for ten hours then your AI will 0.1 apneas per hour.

AHI is the sum of AI + HI.

You mask should have come with some literature that lists the normal leak rate for that mask at a particular pressure.

[pat07011]

My auto is set from 4 to 12. My readings are ranging between 6 and 9.2.

I'm assuming that when there are no apneas, I'm at 4.

I don't like the idea of having my beginning number that low because of rebreathing. Sometimes I feel really lousy in the morning and I'm thinking that might be the reason.

I would like to change it to 6, but I don't know how to do it and I don't want to make yet another trip to the DME 20+ minutes away.

Does anyone know how to change this?

[Wulfman]

Your apneas are probably happening at the lowest pressures.


You mean.....like these instructions?


1. Accessing the Clinical Menu

Turn on the device and wait until the standby (RAMP/SETTLING) screen appears on the LCD.
At this stage you can adjust the ramp/settling time.

Press the DOWN and RIGHT keys simultaneously for 3 seconds to access the clinical menu.


2. Changing Options and Settings.

Press the LEFT (menu) key to access the SETTINGS menu screen.

Use the UP and DOWN keys to scroll through the RESULTS, OPTIONS and SERVICING menu screens.

From a menu screen, use the LEFT (enter) key to access the parameters in that menu.

Use the UP and DOWN keys to scroll through menu parameters.

Use the LEFT key to view or change each parameter setting as required.

Press the RIGHT (exit) key until you return to the standby (RAMP/SETTLING) screen.

[pat07011]

You guys are GREAT! I would know nothing without you. How did you get so smart....or how did I get so dumb?

Wulfman, that's exactly what I was looking for. DreamStalker, you explained it perfectly.

I don't have any leak info with my mask, so I looked online and found something that says the leak index for my mask is 32 at a pressure of 8.0. So, does that mean if my leak index shows .32 or less, I'm in the ballpark?

Thanks again guys!!!! SO SMART!

[ufo13]

Pattie:

I think your machine does the same as my S8 Vantage - It reports the actual leak rate (it has already allowed for the mask exhaust leak rate)! So your leak rate of .30L/S (leak per second) as opposed to the L/M which most leak rates are quoted - equates to .30L/S X .60 (seconds per min) =.18 L/M! ResMed states leak rates are fine under .24L/M! So on our machines anything under .40L/S is OK ( .40L/S X .60 = .24L/M)!

Hope this helps,
All the best,


Steve,
ufo13

[pat07011]

Thanks Steve! Very informative and sounds good to me.

Why do you multiply by .60 and not 60?

Pattie

[ufo13]

Pattie:

That's the way I always saw it done as I recall! It was explained to me quite a while ago by other forum members and maybe I got it wrong with the decimal point etc! Plus I don't type so good! But at 18 you are doing very good! By the way my wife and I are from Jersey (Asbury Park), having only moved to Vegas when I retired!



All the best,
Steve
ufo13

[bgalb]

Like has been stated, the ResMed machines automatically account for the calibrated mask vent rate and any leakage shown on your leakage graph is due to mask leaks or mouth leaks. I use an optilife mask, which normally does not leak at all unless I get really active in rolling around.

My typical nights leak graph shows zero leak for the first fifteen minutes or so, then I start to get mostly intermittent 0.2 liters/second leaks for the next 2 to 3 hours with an occasional short leak up to 0.4 liters per second. I think these are mostly mouth leaks during rem sleep and the 0.4 lps leaks are probably temporary dislogments of my nasal pillows. There will be extended periods of zero leak rate, and the last three hours or so will usually have mostly zero leak with a few small and short 0.1 to 0.2 liters/second leaks.

Have used used heavy mouth taping to get near zero leaks, but my AI and HI numbers seem to stay about the same as when I don't now use the taping and just use my custom-trimmed one-dollar mouthguard. The mouthguard prevents large mouth leaks, but still allows lots of small ones.

Conclusion: for my Resmed and my pressure (9in H2O) , the leaks don't really cause any problems except they wake me up once in a while. If I had constant 0.4 lps leaks I would be concerned but the intermittent 0.2 lps leaks don't seem to be a problem and I intend to live with them unless I start to get awakened too often by the leaks.