The support class has an ability however that allows them to actually bring these soldiers back into the fight even if they start bleeding out.

So keep that in mind because if they're hit while they're on the ground, then they will properly die and be unsaveable. IF you already used the medkit during this fight, might not work. when you're using the guy with the medpack. While laying on the ground those soldiers are still able to be hit by grenades and other explosives, but enemies will not target them directly. You should see a couple icons in your action bar.

Stabilizing will stop the solldier from bleeding out, and they will lay on the ground with 1 health until you complete the battle, if your squad is completely killed, the soldier is lost, if you win successfully, the soldier will be 'Gravely Wounded' and put into the infirmary for a period of time. It's a little hard to see the grid, but the lone soldier at the top of the stack on the left is 3 squares away in a straight line from the MEC using Mist. Here is a screenshot of Restorative Mist in action. Stabilize is a seperate box from Heal Wound. When you first get it you may use it once per mission, if you pick up Expanded Storage as your Captain promotion you get an additional use. That soldier has sustained critical damage and cannot fight anymore, in that case you need to use the other option for the medkit, which will be called Stabilize. If however, the soldier is lying on the ground and there is that beeping at the start of the turn. If this is the case, you need to use the medkit button that looks like the Box with a Cross in it, which will be described as 'Heal Wounds' If a soldier is simply injured in the field, but they can still stand and fight, they will have a red circle around them which will be visible any time you have a unit with a medkit equipped. You said they get shot, then there is a red cross above them correct? So there is usually a beeping that sounds a bit like a heart monitor and the soldier should be lying on the ground. I think what you're describing is actually the soldier bleeding out.

Xcom enemy unknown how to revive