Inverse I:E Ratio - Anything to investigate?

[tigersbowling]

Hello all,

I've been using a cpap for about 6 months now. Unfortunately, I have not felt much benefit despite my numbers being great. Granted my apnea was mild (6.2 AHI, 9.6 RDI), but honestly my fatigue and other issues have only worsened since starting. Now I may have something else going on, and I'm still getting a bunch of tests done, but I keep coming back to my cpap numbers just to see if there's anything else I'm missing. 

Today I decided to look closer into some of my numbers on OSCAR and noticed I have an inverted inspiratory: expiratory ratio. It typically sits at about a median of 1.3. 

I have found mixed information about this. Is this something I should investigate further or is it normal? I've attached photos of a typical night and a zoomed in 2 minute window, which I saw requested on other posts. 

I have an Airsense 11, use a Dreamwisp mask with chinstrap plus mouth tape, constant pressure of 10 with EPR 2. AHI almost always below 1, highest ever was 1.7. I do typically wake up briefly at least 4-5 times a night. But I go to bed at the same time every night, sleep for about 8-9 hours, but I'm still exhausted all day and usually need at least one short nap. 

Thank you!

[G. Szabo]

You should not be worried about it. Your expiration has a long decay that crosses the zero flow a few times, so the I and E figures are corrupted.

[Sleeprider]

I agree. Your I:E is normal, but the extended null flow as expiration ends is resulting in a miscalculated expiration time. This is usually the case when the statistics indicate an inverse I:E and low or normal flow limitation.

[tigersbowling]

Got it, that makes sense. Thank you both!

[ChadBSr]

It is probably fine as others have indicated, assuming that your tidal volume is in a normal range for you.  My I/E ratio was low/equal/inversed but my tidal volume was too low as well.