When DD was in ICU in May, I would have loved some magazines or books, snacks, etc. Just things to fill in time because she was in an induced coma for nearly 24hours I had to sit around & wasnt able to do anything. If its just a couple of hours then she probably wont need much just having someone there to talk to would be a big help.
When Little V was in ICU last yr, was a dreadful time yet having some company and someone to talk to was one thing that can help pass time my sister came and stayed with me at the hospital for a couple of nights and I have to admit, it was such a relief to have someone there to keep my mind off things. So exactly what Daydream believer has mentioned. I think your a wonderful friend being there for your friend.