Such a system would require the force of law. Without it, any doctor or facility honoring the opt-out exclusion would be subject to malpractice and civil rights lawsuits. If that lawsuit resulted in no fault on the part of the doctor and hospital, the program would become at that moment a matter of public policy, backed by the force of law.
Is a DNR any different?
Those who ignore DNRs—except under genuinely extraordinary circumstances—shouldn't be doctors.
And we're back again to the Hippocratic oath and patients who want to die for religious or other reasons.
I'm not sure what to make of this statement because, to the one, there is an aspect about it that is absolutely correct, yet to the other there are frightening implications. In the case of ignoring DNRs, some resuscitations will lead to extended existence in pain. Still, the phrase, "protect the doctors from their tendencies to want to abide by the Hippocratic oath", is ... well, I can see how it could be controversial. Throw that one into the abortion debate and see if we can find heads and tails, for instance.
Doctors usually see the human body in a detached way - they'd have to, to be objective - for them, the subjective aspects are less important than what they can do to prolong life and alleviate disease. The kind of doctors who ignore DNRs are the kind who don't give up on their patients and the notion that they can recover and once again, enjoy what life has to give. In my opinion and experience, those are the best kind of doctors.