First off, I am so sorry you have to go through all that pain.
I understand, as I go through that a lot when they relocate my shoulder.
Fentanyl is actually not a concsience sedation medication, but a strong pain medication. it usually makes people so sleepy they don't react to the pain much.
Just this tuesday I had to have my shoulder relocated. they gave me ativan, and morphine, didn't do a thing, so they tried fentanyl, and it still didn't touch the pain. the doc couldn't believe I was still highly alert and in pain. so they used the actual meds that kind of put you in a twilight sleep. I think they used atomidate ( might not be the right word), and the second try they used diprivan(the white milky looking med michael jackson ODed on). They can also use Brevital which is an old Benzo but it kind of puts you to sleep, and sometimes they use Versed. These meds aren't like general anastesia(sp?), but are sometimes used as "induction" and are short acting.
I don't know if your doctor will use these kinds of meds but you could always ask. When I had nerve blocks in my abdomen they used the Diprivan and a pain medication.
Sorry if that was of no help what so ever. And I really wish this thing had spell check.
Best to you!!