I just want to add a passenger's perspective. I was very appreciative when a medical aide volunteered to help when my son had a severe nosebleed on a domestic flight in Peru. She had sufficient knowledge and great bedisde manner; she even stayed with us for several minutes in the terminal. (He was fine, by the way.) I understand the sacrifice that medical professionals make treating people on planes (or in unexpected settings on the ground, for that matter) but they should know how much difference they make in someone's life.