While it was indeed a life threatening injury, the medical staff at the stadium and at the hospital never considered him in danger. When you have a game like hockey, played with razor sharp blades and constant physical contact, these kinds of things are always a possibility and you have very good medics handy!
If it weren't for them being there, he likely would have died, but with them there to get it under control and the surgeons at the hospital ready for this kind of thing, he was in very little danger really. Still, he lost a lot of blood (I heard someone estimated it at around 5 liters but I don't know how true that is) and his recovery will take some time.
Def