watching impermanent sensation with equanimity

I am going for minor operation. Should I ask for anesthesia or do without it(seeing the unpleasant sensation equanimously) ? And when I have orgasm or very tasty food it's very difficult to see the sensation equanimously. What to do? Any tips to remain in equanimity in orgasm ?(too difficult!) Isn't anesthesia same as alcohol ? (numb your consciousness )