WELCOME! to the forum.!
Hang in there for more responses to your post and best of luck to you with your CPAP therapy.
I agree with PaulaO2. Mine dropped with a low of 85% and the doctor referred to it as "very mild desaturation" in his summary.
Oxygen in the 80's isn't that terrible. On my sleepiest mine dipped to 57% but the sleep study said during titration my oxygen desaturation was eliminated. Before I had the sleep study I had the "at home" study and my oxygen levels dipped in the 40's...
I went into 'smurf-zone'. Back in the day, they would let you drop as far and as long as you did, rather than wake you - because they wanted to know how bad is bad. I hit the low 60s (forget the exact number) for multiple minutes at a time without PAP.
Today, On my Oximeter, I will drop below 88 for a total of about 2 minutes total in a entire sleep session.
*I* am not a DOCTOR or any type of Health Care Professional. My thoughts/suggestions/ideas are strictly only my opinions.
"Only two defining forces have ever offered to die for you. Jesus Christ and the American Soldier. One died for your Soul, the other for your Freedom."