It seems to be a pretty common thing in ground combat. Perhaps you're in a PUG, perhaps everyone is running around solo doing their own thing. Anyways, the enemy gets a lucky shot in (read:wtfpwnjoo@22) and you're down. BUT: All is not lost! For in this game, ANYONE can rez you! So, you sit there knowing full well once you get up you can pop a hypo and be right back in the fight, adding necessary firepower to your side. But...wait! What's this? No one is rezzing you! They're just standing around waiting for the enemy? So you yell, and they run off. Leaving you to re-spawn, usually far from the others with multiple enemies in the way. Of course, your group is now outnumbered by the enemy and before long they are helplessly splintered, and thus easy pickings, for the better organized team (usually the Klingons) who end up wiping the floor with you 45-5.
Folks. EVERYONE CAN RES. And it only takes a few seconds. DO IT. Sure, there's no death penalty. Sure, respawning isn't that big a deal. But that extra phaser in a fight might be what it takes for YOUR side to WIN the effing PvP match! Jim Kirk would do it! Captain Picard would do it! Janeway would...well, she'd probably get lost looking for you then conquer a civilization for a cup of coffee while crying to Chakotai about how no one understands her needs...but I digress.
For those who didn't know, it's the CPR key, usually defaults to skill #5 I do believe, at least for tac officers. Please. Don't leave a fellow officer to moulder in the dirt. Rez him.