It looks like the videos have been taken down. I saw one earlier that was truly harrowing - blood everywhere, on the ice and down the front of the player's white uniform jersey, as the player was led to the sidelines by a teammate after having his throat slashed by an opposing player's skating blade.
If you didn't know better, you'd think it was a sacrifice.
It happened in a high school game here locally, like 20 something years ago. Kid survived somehow, and then neck guards became a requirement after that.