Unusual sleep study results

[TorturedSoul]

Hello all. This post has to do with my daughter who like me has autonomic dysfunction. She had a sleep study done that really stumped the doctors. She stayed at below 95% oxygen saturation (90-92%) for 95% of the time she was sleeping. I was shocked. She had very few apnea events and no hypopnea. Her CO2 also didn't go above 50. The doctor has no clue what to make of the results. I'm very concerned. She definitely has sleep issues. However whenever I have tested her pulse ox at random times throughout the night it never registers that low. It actually was 99% every time I tested Last night. She saw a cardiologist last year and everything was normal and she did amazing on her breathing test so dr felt it wasn't her lungs. She said that leaves neurological causes. Could it be POTs that affected the O2 reading? I just can't understand how it dropped that low all night and yet when we test at home it's never that low. Also very few apneas and no hypopneas. I would think if it was neurological or neuromuscular something would be off there as far as apnea/hypopnea.  Does anyone have any insight? 

[MomtoGiuliana]

Here are some past discussions that may contain something useful:

https://www.dinet.org/forums/topic/22840-can-pots-cause-low-02-saturation-levels-pulmonologist-wants-me-to-have-surgery-%E2%80%93-need-feedback/

https://www.dinet.org/forums/topic/26501-is-low-oxygen-reading-common-in-pots/#comment-246802

Is it possible their equipment was malfunctioning?  Especially wonder if the dr is stumped and this has not been observed at home.

[TorturedSoul]

I have been using several pulse ox monitors over the years. Never did I get readings that low, but I couldn't measure continuously. Even so if the report said it was low 95% of the time you'd think I would discover similar results during the random times I have tested. I hope it was an error. Im waiting to hear back from her doctors. Thank you for taking the time to reply