It's a good thing that Philadelphia Flyers forward Jakub Voracek wasn't injured on this play, but that should not be a factor in the severity of a penalty when it comes to these types of hits.
Washington Capitals forward Jason Chimera absolutely crushed Voracek from behind during Game 5 of their first round playoff series, sending him flying into the boards, head first, with a hit that looked like it was going to have a horrifying result in real time.
Upon watching the replay it's even more impressive Voracek wasn't hurt after the way his head was pancaked against the glass, and it becomes more difficult to understand how Chimera was only awarded two minutes for this infraction.
Needless to say the Flyers weren't very happy about this one.
Here's another angle.