Thought I would share some of my experiences.  I had RNY with Dr. O'Rourke at OHSU. The OHSU team is a wonderful team for pre and post surgery. Anyway, the night before my surgery, my wife and I came to Portland and stayed in a hotel room since we live 3+ hours away. My wife insisted that I clean out my system with MOM (Milk of Magnesium...or however it's spelled). I stayed awake until about 1am thanks to that, and was still running in the morning (although that's probably due to nerves).
  Showed up a little late because we were told to go to a different place, but it didn't seem to matter. We showed up at 5:30 and I was given a gown, a bed, and a TV remote. I took all my stuff and made sure my wife had it. OHSU took my CPAP and "inspected" it. It was kind of odd, but ok. At about 6:30 I had a bunch of the OHSU medical teams come in and ask a ton of questions (didn't I just tell the last 12 teams that same info? Ask them!) My veins suck, so they had some problems with getting in my initial IV (they had to use ultra-sound to find the vein). I gave my wife the last smooch right as they gave me my sleepy meds. Wheeled me into the OR and made my way onto the OR bed. As I was told would happen, a lot of medical people came at me to start doing what they had to do. My anesthesiologist (the pain person) held a mask on my face and soothed me with her voice while I assumed she was putting me to sleep. 
  I woke up in recovery and had a nurse keep telling me to breathe deeply. As you can imagine, I didn’t want to because of the pain! Finally when they were getting ready to move me from recovery into my own room, I asked what time it was and the reply shocked me, even in my state of druggedness. “3:30.” WHAT?!?! 3:30!!! My poor wife must have been wondering that happened, but later she told me that they called and updated her twice during the surgery.