Thanks again all.
Wasn't pleasant doing mouth to mouth as you say, but adrenalin kicked in and just got on with it.
He was unconscious and passed calmly, don't think he new we were helping him, but I was talking to him and comforting him anyway incase he could hear me.
There wasnt any heroics, you dont have time to stop and think. It's a major life experience I won't forget, but nothing to what many in uniform have to go through on a regular basis.