[Treatment] AHI 0 one day, AHI 42 next day - Huh?

[tenter]

Hi,

I'm feeling lost and confused. On some days the Oscar reported AHI is low, and most days it is high (40s, 50s, even 60s). The low AHI seems to correspond with a lot of large leak, does large leak prevent Dreamstation detection of OAs?

Probably more important is resolving the usual high AHI, any suggestions welcome. FYI seeing pulmonologist Monday.

Background:

I used a Dreamstation CPAP maching for about two years, never thought it helped me. Earlier this year I complained to my pulmonologist, and as a result I had a BiPAP (titration?) sleep study. I don't think it is helping either.

Note, at the end of the sleep study, the technician said that for the first half of the night, the apnea was well controlled, but the second half of the night it was not. So they were hoping that the BiPAP machine would work for me.

OSCAR charts attached showing low and high AHI.

Thanks.
       

[SarcasticDave94]

Welcome to the Apnea Board.

Yes, I'd say that the very high leak rate of 80% + would prevent any machine to give proper reporting and therapy. That leak likely comes down to mask fit and adjustment or a mouth leak if not on full face masks.

[PaulaO2]

Think of it this way. If you are trying to put air in the tire but it doesn't fit right on the valve, more air is going out than in. And if you activate the commercial version's tire pressure gauge, it can't report the pressure the tire has in it because it isn't fitted the right way.

Masks are the same.

Full Face Masks are notorious for leaks. It is also possible that some nights, you sleep in such a way the mask has no physical push on it (pillow, shoulder, whatever) so it stays in place. Other nights, it is being moved out of the way so, it leaks. Another possibility is you are sleeping on your back, requiring more air than the mask was fitted to handle so it leaks.

Look up your mask on YouTube and find fitting videos. A lot of the times, one or more of them will have a tip on how to get it to fit that works for you.

[Sleeprider]

Tenter, the difference between the two graphs is the leak rate. The problem here is that you have persistent clusters of obstructive apnea that continue regardless of the pressure your machine produces. This is probably a form of positional apnea where you're tucking your chin and closing the airway. No amount of pressure can open a closed airway , and you don't seem to change position or free up your airway. Without a doubt you need a soft cervical collar and other adjustments to your sleeping position. Fewer pillows or a smaller one may help. Read the wiki in my signature links on the Soft Cervical Collar to see examples of how other members have resolved positional apnea. Be sure to follow the links to the Posiitonal Apnea wiki in the Optimizing Therapy Wiki. This problem is fairly easy to solve.

[tenter]

Sleeprider,

Thanks for the info, will check into getting a SCC.

[tenter]

Update:
Turns out the air leakage was a plumbing problem... there is an adapter between the mask and the hose which is loose. I taped it as a test, and now leaks are much lower.

After some research and experiments, I found that a different sleep position allowed the BiPAP machine to work better, see attached chart

Still not sleeping well, will work on suggestions in other threads (sleep hygiene, etc.)

Again, thanks for the suggestions!

[SarcasticDave94]

Definitely going in the right direction after the leaks are better controlled.

[Dormeo]

Wow, that is a dramatic difference! For the benefit of other people with a similar problem, could you say a little more about how you addressed sleep-position issues?