Safe endoscopy and sleep apnea..what if you don't yet know if you have sleep apnea?

If you haven't had the sleep study yet, but they're putting you out for an endoscopy, how safe is the procedure? I have been under general anesthesia before with no problems, but that was at least 2 years ago. I'm a little concerned.

We greatly appreciate your interest in helping us build our Q&A database. To discourage vandals from posting garbage, however, we require people to register before posting.