I have sleep apnea as well. I had previous complications when I woke up from having gallbladder surgery, my oxygen levels would not come up. I was so scared to have this EGD, so scared to be put to sleep. But I was told it was nothing like when u be put to sleep when you have major surgery. And they were right. I had my egd on Friday, they knew I was so scared. The Dr put on music, I saw him move to the music, I smiled then I was knocked out. Having an EGD is so fast, I was back to my room within 30 mins. I woke up with no pain, and the best sleep ever. My oxygen levels was perfect. You will be fine hun.