She is absolutely terrified...statistics prove, and those abused Know, in their heart, that the most dangerous time is when you get caught leaving (It is total defiance to the abuser, after all). Plus, she has been convinced he is "the only one who could ever put up with her badness, ugliness, etc etc etc".
Been there, lived that, got out.....best wishes to her! And the best line you can take is just repeating, "you are worth better".

People who repeatedly find themselves in abusive relationships find it hard to leave. That's why they are stuck. They might confide in people hoping to find not only a listening ear, but some reaction that validates their own concerns, and perhaps a solution or support in making a break safely. They may not feel safe in heeding the advice right away, but they do remember it. Just having their concerns validated is helpful in itself.

Calling someone stupid, or writing them off, because they are being victimized and can't see a way out isn't going to help anyone. She's not stupid, but maybe was brought up to be loyal to men, no matter their behavior, and dependent on them.

You might get through to her by pointing out that your whole office could be in danger. Sometimes we will accept abuse for ourselves to please our abuser, but can actually draw a line when it comes to other people. She needs a sympathetic ear and professional help to give her strength.

Your gut is telling you that your office could be in danger because of this guy. Tell someone with the authority to share his photo with security or something?

You can't change anything for her but you should do what you can to protect yourself. If the man is calling the hospital that often, the hospital should be able to take legal action against him. You may even be able to get him banned from the premises so that you can call the police the moment he enters the property.

I know how messed up your head can get in an abusive situation. If he's that nuts, is no wonder that she's not acting rationally. Unfortunately, it also means that you probably won't be able to talk any sense in her no matter how hard you try.

If you want to help her, I believe the best thing you can do is be supportive of her so that she can trust you to help her out, if she ever decides she wants help. Showing her respect and kindness may help her decide to look for something better but sometimes people are beyond able to accept good things. That said, in any situation of abuse and in this one particularly, you need to be careful about setting boundaries in your help so that you don't end up getting harmed in the process as well.

Surely she can get a restraining order and report him to authorities by recording some, if not all, the conversations? I would tell her to fuck off telling u about the situation unless she does something about it, or u, or someone else, will. This seems waaaaayyyy too volatile to shrug it off. She needs to understand that!

CUT HIS FUCKING FINGER OFF!?!?!
Call the cops!!! That dude is a psycho!!!!!!

It sounds like he could be a threat to her co-workers as well. If your workplace has mental health care insurance, please encourage her to use it.

That is some scary shit! Do the cops and hospital execs know about this? Be careful!

Wow. I've seen people tolerate abuse, but that's next-level Stockholm. Bad news all around.

This is the part of the situation where every one gets friendly, just before the knives and guns come out. If she works near you figure out a way to get low and out of there quickly. If something happens get out of there I do not want to hear that you have been harmed. Be safe.

Human Resources. Not your circus not your monkeys - someone higher up needs to be made aware and deal with the possibility.