Be careful when going to save a teammate. The enemy may be using them as bait or might just be around the corner with backup. Your rescue just went from bad to worse because you did not see the tactical hiding behind the window or the jumpack who decided to join the fight. If your a non healer see if you can clear the area or stand close to the downed player while you wait for a healer to come. If your a healer make use of your long range heals or heal grenades. Certain races even have a fire and forget heal which is very useful for saving someone in the middle of a fight. If you are downed get to cover asap. You can also choose to sacrifice yourself by blocking a doorway or sitting infront of an objective.