Look it can make her feel energetic once she gets oxygen! The hypoxia can cause heart attack or stroke. Plus, Cpaps have come a long long way.
You can use nasal pillows now, instead of a mask & it just forces your airway open if you stop breathing.
It’s so wide & soft, you don’t feel like anything is in your nose openings !
Plus hypertension goes away too often after use of Cpap at night!
But if they have not run a. MRI of the c-spine, see if the Doc can, b/c by her positional symptoms, being fine & then getting worse, that often happens when the nerve is compressed more, so lifting, pushing , carrying groceries or laundry can bend the neck & that would cause her to be fine & then get worse! That’s probably why docs were previously testing for orthostatic hypotension!
The reason I know, is b/c I’ve been there, and was shuffled around, until I saw on an MRI cord compression at C4-C5 and subsequent surgery to lift the disc off the cord relieved all the symptoms!