If bakers can choose their customers based on sexual orientation doctors should be able to choose their patients based on political affiliation. At least one of these is a choice.
I won't comment on the politics angle, but at the very least I think health care should go under a shared code of not being cruel or combative with the workers who are providing you care.
I understand that you can't just kick someone out to die on the street, even if they're being an asshole, but I think that a lot of people predicate their behavior on the fact that you can't kick them out to die on the street. I think it would be much better if there was an understanding that you are leaving the hospital if you abuse the people there, and you can come back the instant you agree to behave, and we'd really like you to agree to that, but we can't care for you until you do, no matter what thing is going to happen to you without care, and that's a hard boundary. The people providing the care need to be cared for, too.