Kathy and Juan,
Good luck on your surgery and taking back your life. Remember, positive thoughts and after surgery, walk walk walk. In regards to the protein shake the day of surgery, they want your stomach empty so you will not have anything to eat or drink that day. The day before surgery I believe that it is just liquids. They will go over that when you get down there. Just relax, I know easier said than done, because you have done great so far by losing the weight. That will help your recovery after surgery.