Hello,
I have been using a Resmed Air Sense 10 for 2 weeks or so. Doing well in general, but have trouble getting consistent mask seal scores. Last night my mask seal was 0/20, yet my AHI was reported at 0.6. **Will the AHI score be accurate if the mask seal is really bad, or does mask seal have no effect on the machine's ability to record AHI accurately?
Thanks for any insight!
Tracy
Hope this makes sense... just my experience but the ResMed POINTS are not the issue. Look at your LEAKS PER MINUTE. You can get zero ResMed points but your mask can be sealed a bit and well enough where it won't affect your AHI as the machine can compensate a bit. If the LEAKS PER MINUTE go off the chart, then your therapy will no longer be effective and your AHI WILL GO UP. When I struggled with mask leaks, my L/Min could be 30 to 50 and there seemed to be little effect on AHI. Up over 60? The AHI went up. The highest leaks were caused by my jaw sagging and the lower part of my full face mask would end up in my mouth. One massive air leak and the Aircurve 10 couldn't compensate I guess. Not sure what the exact leak level vs machine compensation is but there is a number. The .6 AHI you got tells me that even though the mask was leaking some, the machine was able to do its job; provide positive air pressure and it kept your airway open. FYI: Last Thursday I had BAD mask seal and got ZERO RESMED points; about 60 L/Min. Usually I have almost NO leaks. Still had AHI of .2. In the past if over that L/Min value perhaps AHI of 3-5...
A leak under 24 on an AirSense 10 is not too bad. The machine should cope fine. If you have an AHI of 0.6 at this level of leak it should be reliable. I've never paid any attention to the point score that the AirSense gives because it is ultimately meaningless. As a professional I want objective data which is comparable to other historical data, not some arbitrary rubbish that ResMed has made up. The leak rate in L/min (that's litres/minute in case you are wondering) is a universal standard for mask leak. ResMed machines do deduct what they think the controlled leak level should be (the air which comes out of the exhalation port) from the score you see, so it is possible, in some cases, to achieve a leak rate of zero. If you use a different brand of machine it will not do this, and even a perfectly fitting mask will still have some leak reading (because there is still air flowing out of it through the exhalation port). So one brand does not necessarily compare directly with another. If the leak level is high enough it will interfere with the machine ability to detect apnoeas and hypopnoeas.
I have not found any correlation between mask leak and events.
Main problem with a mask for me personally is if the mask slips into my mouth off my chin if my jaw sags. This will create one massive leak condition and I am sure that positive air pressure just can't be sustained when the mask is in my mouth. L/Min values will be well over 100 and AHI DOES go up. Other than the mask slipping into my mouth, I don't see much correlation between mask seal and AHI. Mask seal can spoil your sleep if air is blowing in your eyes and your mask is making disgusting noises.
Mask leak does not necessarily affect AHI, but it can. If it is big enough then the pressure in you upper airway will be insufficient to keep it open. And if your leak is huge, the machine sill simply not record data because it can't tell what's going on. However, in most cases mask leak has minimal effect on AHI. We usually tell people that if it's not disturbing you then it's not a problem.
if your leak is huge, the machine sill simply not record data because it can't tell what's going on
Okay, this is disturbing. Because my leak is huge. But I can't seem to figure out what the problem is.
A huge leak will be easier to pinpoint than minor seal leaks with air blowing into your eyes. Where is the leak? Do you have some numbers like L/Min?
pattyloof, I have had a problem with major mask leakage for a long time. What I've been told is that, even though my AHI appears to be low, a mask with that much leakage isn't going to record the data reliably (just as sleeptech said above). One of the sleep reps at my supplier suggested I try the AirTouch F20 mask once my insurance allowed me to get a new mask. Finally, yesterday, I was able to get it. It uses memory foam. Last night, my mask leakage was 0.96%, the lowest it's been in a long time. It's a shame that the insurance companies will make us wait even when there's a good reason to switch. But call your supplier to see when you can go for a mask fitting and a new mask. It shouldn't be more than 3 months after you received your last mask. You can ask that the Airtouch F20 be one of the masks you try, but there might be other options that work better for you. IMPORTANT: They didn't tell me until a few days ago that I needed a prescription for the Airtouch F20. Which is silly - there's no reason why anyone would need a prescription for that mask over others. But it's important you know that so that when you're able to go in for your fitting, you can take the mask home with you instead of being surprised and finding out you can't get it until after you can get a prescription. I hope that's helpful.