Indeed. When my daughter was in Nursing School, they assigned her to the oncology unit for her 6-month practicum. It was very hard for her to provide the best care she could for patients, only to see so many of them die. I guess that's kind of why she is now an ER Nurse; granted, she still sees death there, but whenever that occurs it's rapid. And borderline cases get sent "upstairs".
Working in ER has the benefit of fairly rapid patient turnover so that the personnel don’t have a lot of time to dwell on things.