nurses have sixth sense

Nurses do indeed have a sixth sense. No, I didn’t misspell “sick” sense. I mean, we have an instinct that civilians don’t have.
The nursing “sixth sense” is that moment when your gut gets those “butterflies,” or when A plus B does not equal C.
It’s a part of that ever-important skillset of critical thinking, but it’s also a separate entity altogether. Maybe you can call it a form of ESP: