On a tangent, not all doctors are suitable for emergency work. I used to work with a paediatric neurologist, who was excellent in her field and a respected specialist, and she told the story of the call going out on a plane for a man who was having a heart attack. She hesitated about it - she hadn't "done hearts" since medical school twenty years earlier. Just as she was about to volunteer, however, another doctor put his hand up... and he was a cardiologist.