The twighlight sedation is probably what we call conscious sedation, it is usual a combo of two drugs versed and fentynal, although there are many others they may chose from. During this time you maintain control of your own reflexes. For example, you breath on your own and are not intubated. Technically, you will be able to hear what is going on, you just will not remember it.
They use this type of sedation for many procedures, such as endoscopies. They may also use it for certain surgeries. I had to a some serous surgery on my foot last year. I originally thought I would go with the conscious sedation. However, when I was there, I realized I didn't really want to be hear the saw ( or see the saw) that would be cutting a large part of my first metacarpal off, so at the last minute I changed my mind. As a nurse, who never wanted to be an O.R. nurse, I decided i didn't want to be "present" for the procedure.
The surgery you are talking about is fairly major. If your concern is safety or immediately post op, I can tell you that I have professionally seen very few complications as a result of anesthesia. There are always possible complications, but often that has more to do with the surgery rather than the sedation method.
I just figured I'd add this to give you a balanced view point.
Good luck on your surgery, I'm sure whichever method you decide on, the results will be worth it.
