WOW this really strikes a chord in me ... I have the same fear!   I always have ever since I can remember. I am so sorry I know how you feel and it makes me sad for you. I don't know why I have this fear ( I too thought it may have been from a past life but not sure ) ... therapy has suggested that it's my fear of being vulnerable... apparently it's a fairly common thing to happen to anyone who's ever been taken advantage of or the like. Could this be relevant to you?

If you need the surgery, get it. Try to think of the odds. Don't allow your fear to cause you suffering. I know that if my life, or way of living, depended on a surgery, I'd get it  (if I didn't have a heart attack thinking about it first ).

Best wishes to you, you're in my prayers.

The fear of surgery has two main causes. First your soul experienced it in it's past life and it was very unpleasant to her and she remembers it subconsciously or two your soul subconsciously knows that it will happen to her in the present life. But there are also other reasons, however not that frequent, like for example a fear from what is not supposed to happen.

so have you known for this actually to happen?

Instead of an answer, I will rather recommend you to download and read books about these things from my web site:

http://www.spiritualknowledgebooks.net/