I just found your discussion regarding air under the skin. My horse has the exact same thing happening right now. He punctured his chest with the blunt end of a pitch fork and the drain the vet put in let air in but not out. The drain is out, but the puncture is still open (it has to drain). My horse is so full of air, he has lost the definition in his face. How long of a recovery period did you experience with your horse? I am worried, because my vet has never seen this before and can't give me many answers.