I don't agree that heroism is only a one time impulsive act of sacrifice. By definition a hero has courage, is responsible for outstanding achievements, and identified with good qualities and sometimes is considered to have semi divine origins. But mostly, the word hero has been relegated to men and so the what we have is an idealized idea of a hero. I believe caring, endurance, and nurturing those who are the most vulnerable, and helping others makes a nurse a hero. I mean unless she has a lousy attitude! Then she or he is just a pain in the butt.