Yes. My wife had this sense of peace and perspective when there was a small chance she might die during childbirth. I, on the other hand, was a total sobbing mess.
Since then I've read a book that suggests this feeling of inner peace comes from an intense focus on the present moment, and that's why it often happens during crisis scenarios. It says a lot of other things, like that it's impossible to completely focus on something without accepting it nonjudgementally, and that the entity of you is not comprised of your thoughts or your emotions, and that your thoughts are no more you than your leg is you. The real you is your awareness behind your thoughts, that is, your attention or observation.