Yes, I cannot imagine how people work in some of these fields. A lot of the pediatric specialization comes to mind also like oncology, cardiology. That some people can and do take the burden is the reason lots of those kids get to live.
I once asked the nurses in the intensive care ward, where my baby son was, why they didn't work with adults rather than children. Surely the heartbreak was hard to cope with? They said it was because children didn't know they were supposed to be ill so they didn't lie around moaning like adults did—as soon as they felt a little better they would jump up and go and play with their toys. It was much more satisfying having patients who (if they got better) you saw go from coma to running around again full of joy.
Management of and varying response to compassion fatigue.
There's a happy period where you're doing extremely fulfilling work, then a difficult time when you're distraught at your failures, then a complete indifference to suffering that you've normalized.
Managing fatigue and stress in any job is extremely important, managing compassion fatigue is even more so.
My mom worked in the neonatology ICU for years, and while every once in a while there was a tragedy which made her very upset, not many bad (and unexpected) things happen these says. It's a very rewarding job, as you help start a life.
Alas this can only be said about the first world. In less developed parts of our world this would be the complete opposite I imagine.