Sadly, I know from where you come on this since blood thinner, Coumadin, was instrumental in my late wife's death.
She broke her leg and she had to come off Coumadin for surgery. She had a stoke during surgery which led to bleeding on the brain and she also had an artificial heart valve and further surgery was out of the question. She lived a week after the leg surgery passing quietly on July 4th, 2010.
I hope and pray that your wife will come through this and can get on with her life.