Anytime your oxygen drops below 88 it causes brain and nerve damage. So 76 is serious. I use a BIPAP machine, which is a
CPAP with
oxygen ... it keeps my levels right where they want them...97 for me. I use oxygen 24/7. I'm 53, smoked cigs for 30 years, have been off them for three years. I no longer crave the nasty things.
Yes, I think the oxygen at night will help you. That's how I started out, then as I got worse I need it all the time now.
Good luck with your breathing.