Blood Transfusions saved lives but have also taken lives. As A JW I would not accept a blood transfusion on religious grounds, even if the blood could be sterile and pathogen free, I would not accept a blood transfusion based on what the Bible says to "abstain from blood."
As a medical doctor I could not honor any medical directive from someone that did not want blood for religious reasons. I could honor the directive as much as possible and if possible, but that would be a medical decision for me to decide, but I would try to honor it. I would not have a person die on me given the chance to live using blood. If a person wants to die on their own, I cannot stop them but once a person is under my care, I must use all of my powers to save his live. And In good conscience, I could not honor a directive short of a miracle from God not use blood if it was medically necessary. As a medical doctor, it would be a violation of my oath not to use all of my powers to save a person's life. In the US, there would be legal consequences but I would fight as much as I could to save the patient. I would fool the patient if I had to and I would do everything in my power to save his life.
As a judge sitting on Caesars throne bearing the sword, having the power of life and death; short of a miracle I could not affirm any medical directives restricting lifesaving medical treatments on religious grounds. Of course I would have to hear the case, but my decision would be grounded on scientific medical opinions not on refusal of medical treatment for religious reasons.I would not buy the argument that blood is too risky when the benefits outweigh the risks. Not being a JW, and as much rights JW have to practice their religion, I bear the sword.