[@Silver Fox] I see. Well, you should know that neither Cas nor anyone else aside from me and rivaan were part of discussing what this attack entails. I did not, however, ever specify how much blood would be "Lost" during. That was my error. The amount lost would be about 1/3 the total amount currently in the body. 

And though it sounds scary, 1/3 is not fatal, but there is the risk of it. The blood spike probably was easy to imagine larger, and i did describe it on the bigger side, but don't forget that when water, or in this case blood, expands when it freezes. She is still highly at risk for hypothermia with the combination of blood loss AND ice.

Here's a video explaining it a bit better (relevant at the 2 minute mark), she would be considered a Class III
[youtube]https://www.youtube.com/watch?v=JQwJVfVAPLQ&feature=youtu.be&t=2m17s[/youtube]

video courtesy of Cinderella Man and Experiment 249