I'm a physician and during my endless nights in the ER I've heard a symphony of ungodly sounds, be it agonising gasping for air, gargling on own blood, hellish dry heaves and vomit sounds, the sound of a drainage catheter entering the brain to remove blood from the ventricles, the sound of a blood gas needle against the bone.

When you're on work mode it's all white noise to you, you don't have time to process it and I never was shocked by this stuff anyway.

This one time though, I'll never forget and it wasn't even something I had to deal with. I was in a small break room in the ER, when the ambulance delivered a 50 y.o. man in the cardiology room, DOA. When they apparently told the news to his son, his screams of "FATHEEER! FATHEEEEER!" managed to make a full ER facility with 100s of people and stuff inside to fall absolutely quite.

It was the single most eerie experience in my career so far, nothing has come close to that.