Going to get an upper endoscopy done, should I ask for any particular drug?

I have to get an upper endoscopy done in a few weeks and I'm pretty damn scared. I have a high sedative and pain killer tolerance from being an alcoholic for 15 yrs. When I had my cardiac cath. done I was still awake and could feel everything, it sucked. I know for sure I want to be out or as closed to out as one can get to not know whats going on for this procedure. I can't even swallow pills without choking. What would be a good drug or anesthesia to ask the doctor to use? It's not so much the gagging or vomiting that scares me as alcoholics do that all the time. It's the choking to death, suffocating or feelling of panic of having a tube shoved down your throat that scares me most. Please help me out here and if you have something negative to say, keep it to yourself. Thanks...