[Treatment] Leakage and AHI accuracy

[Mlidoudou]

Hi there:

My father has been trying Airsense 11 for 2 months and we have found face mask is best for him in terms of leakage (usually around 4L/min).  The next best is nose mask but using tape to seal the mouth leaving a hole (for safety reasons).  Leakage can range from 18 to 35L/min).  AHI is usually low, around 2 or less. With face mask, AHI is higher, ranged from 1 to 14.  When I checked the data on Oscar, there are periods that are grayed out (leakage higher than 24L/min) when there is mouth leakage with nose mask.  And I never see any events in the grayed area.  The flow rates often have consistent small amplitudes in the grayed area (but not small enough to be called apnea).  I am just wondering if the AHI can be trusted.  Is it real that there are no events during mouth leakage? My doctor thinks that it is exceptable when the AHI is low even when leakage is in the 30’s and 40’s. Does any one else have this problem?

Thanks,
Maggie

[SarcasticDave94]

The mask that has that high of a leak rate, median 13, 95% 38 etc., and large leaks of 29%, this all means it's not working period. Being a nasal mask of some sort with high mouth leaks, it's not working out. It means also the events accuracy is not existent, do not go by events to grade effectiveness, with this situation. Best to stick with a mask that has a lot lower leaks.

The accuracy of the therapy is being affected because the CPAP cannot keep up with the leaks. That's why the gray large leaks are reported. The leaks are so much it's as if the mask isn't on.

[Mlidoudou]

Thanks for your reply. But when I am next to my dad, I do see him breathing when he is having those large leaks although I cannot judge the depth of his breathing. My dad also thinks he slept well and feels refreshed.

Is it possible that the mouth leaks (along with the blowing air from the machine) is somewhat helping him to breath? Is the machine still able to accurately measure flow rate during those mouth leaks? If so, does that mean there is still breathing but the amplitude is less with each breathe? Can this be the reason why there was no events during those mouth leaks and the therapy was still effective?

[SarcasticDave94]

Breathing still will happen even with large leaks, but that's not the problem with dealing with CPAP. Large leaks like these reduce the therapy effectiveness. So again don't trust the no event aspect.

The leaks are large enough where the CPAP cannot sense events, and it cannot respond to anything because it's trying and failing to keep up with high leaks.

The suggestion is use the mask that doesn't leak that much.