Hoo boy. So many feelings here.
I gotta say, I've had someone try something pretty similar to what Vick just did to me during a PTSD flashback and...opposite of helpful. Longest freaking panic attack ever. :/
Characters are free to do as they like because fiction, but please, please, please do not ever do that to someone in real life. You can't 'shock' someone out of a panic attack because their fight or flight response has already gone totally haywire. You want to stay calm and speak softly, try to get the person to notice details about their current surroundings. This can help the person separate memory/fears from reality so they can calm down.
Thus endeth the public service announcement