Any relief he could have had at Powell's being alive is snuffed immediately. Still--a M*A*S*H doesn't refuse to treat someone just because they're the worst person you've ever met. They treated the enemy, too. It's not their lot to cast judgement like that. Only to heal.

"Keep him out of this or I'll lay you out again, and you won't like how I do it!" he snaps, as he gently tries to ease his arms around the man to carry him from the altar. "You know as well as I do that it's only the luck of Providence that of all people to end up here, it should be me."