I'm so sorry to hear of the condition your dear friend is in, dear lady.
Unfortunately, your friend's doctor(s) may feel that it would serve no useful purpose to inform your friend of just how bad her condition is. Sadly, not everyone is able to handle the information in a way that they wouldn't feel terribly anxious/distraught at the thought of what's to come.
It COULD be that they feel things have already gone too far, and are deliberately avoiding upsetting your friend.
Will the doctor(s) speak with you about your friend? I'm assuming that as you're not a relative that they MAY not. Are there any family members around? They MAY have better luck with talking to the medical staff.
Are you actually sure that the medical staff believe there's little more that can be done for your friend? It MAY be that they believe your friend isn't in quite such a bad state as you think she is. This is something that needs to be clarified. You MAY be working yourself up over something that's not going to happen.
Does your friend have any religious affiliations? i.e. is she Christian, Muslim, Sikh, Buddhist, Pagan? Maybe you could arrange for a representative of whichever church to speak with her?
Have you tried talking to your friend yourself? I'm not suggesting that you be the one to tell her how bad the situation is, but have you listened to what she's saying? She MAY already know that things aren't looking good, and she MAY be trying to avoid upsetting you.
I appreciate those last few comments may seem a little strange to you, but I've been present at a few hundred deaths, and you'd scarcely believe some of the 'secrets' that people let you in on when they know that their time is near. Just be there for your friend for when and/or if she wants to say something to you ... and do, please, take care of yourself. If there's someone that you need to talk to, do ask. You'd be surprised at just what help there is available ... and don't keep things bottled up inside.
Blessed Be, my friend.