mask leak - how much it too much

[Artimus60]

Hello all,

Issue: my mom's leak/LPM has gone up the last 2 nights and her AHI (especially her centrals) have gone way up - I'm wondering if there's a connection.

The Details: She's about 2 months into an attempt to treat what has been diagnosed as severe sleep apnea. She started with a CPAP machine and was fairly quickly moved to a BiPAP asv advanced machine as she was diagnosed with complex sleep apnea. Her AHI has remained quite high (>35AHI) for most of that time. About a week and a half ago her doctor made some adjustments to her EPAP and PS settings and it seemed to do some good as her AHI began to head in the right direction, eventually getting as low as 11AHI (still high, I know, but everything's reletive and when your quality of sleep has been as poor as hers has, 11AHI can seem like sweet relief). She had a really crummy 'couldn't get to sleep all night' experience 3 nights ago and her stats from that night were undestandebly poor. The last 2 nights her numbers have been a big step in the wrong direction and she's even more fatigued during the day than usual. During those two nights she's used a PadACheek mask liner for the first time. I've heard nothing but great reports regarding the PadACheek products and I'm confident that she'll like the liner but, for whatever reason, for these first couple nights her leak/lpm has gone up. Her average lpm has been around 35 but the last couple nights it's been over 40. I'm wondering if this could account for or contribute to her big jump in central apneas and the plummet in her 'patient triggered breaths'. I think I'm going to try not using the PadACheek liner tonight and see if that has any impact on her stats and the way she feels on Sunday. I've done some searches on this site regarding mask leak and I found the 'Introduction to Mask Leaks' document but I'm still a little hazy on what's considered an acceptable level of leakage.

I've included the following screen captures of data returned using EncoreBasic.

Trend Data Showing Increase in CA's


Last Night


Thanks in advance for any observations that you might have or any personal experience you've had that might help to shed some light on our situation.

artimus60

[Artimus60]

groan - how much IS too much?

[Pugsy]

The leaks are minimal and not causing the increase in events.
Respironics machines report total leak which is the mask's intentional leak/vent rate plus any excess leak.
You know I have no experience with this machine so I really can't offer anything there.
But the leak would need to be doubled before I would worry about leak. Large leak territory is somewhere between probably 75 and 90 L/min. We aren't ever given a set number but her numbers are well below large leak territory.

Now if she is having her sleep disturbed by any leaks (even if minor) then that could account for poor sleep but more from the fragmented sleep and not because leaks are large.

In her mask literature there should be a graph for intentional leak at your mom's pressure.
If you don't have the paperwork the vent rate can be found on the internet.
Vent rate increases with pressure and full face masks have a greater vent rate than say nasal pillow masks.

[Artimus60]

Hi Brenda,

Thanks for your reply - I kind of had a feeling that was the answer. I know that my mom has an ongoing leak rate but I didn't think it would be enough to account for the drastic change in her AHI count. I'm frustrated as she seemed to finally be heading in the right direction. Back to the drawing board...

Thanks again for taking an interest and sharing your knowledge,

Mike

[greatunclebill]

the quattro intentional vent rates at pressures of 8, 12, 16 and 20 are 32, 41, 48 and 54 respectively. so if you're looking at total leaks in the graph and subtract these numbers, your unintentional leaks are not bad at all.