it depends on what you are having done, I am 4 weeks post bilateral mastectomy and tram recon, it was longer than 8 hours... my breast surgeon did the mastectomies first, then the plastic surgeon came in to do the recon.. I woke up very quickly after the op, and was back in the ward within the hour. Nurses kept a very close eye on me and were wonderful during my entire time in hospital.. I too was petrified when the surgeon told me how long, and nothing anyone can say will take that away from you, having confidence in the medical team treating you and let them know how you are feeling. all the best with the surgery, sending a big virtual hug