A long time ago when I worked in the event industry, my boss quit right before a big conference. I had to pick up 90% of his responsibilities which had me working 16-20 hour days. On the morning of the 4th day, I passed out from dehydration and woke up on a gurney. I stayed at the hospital for a few hours until I was clear to release.
A month later, I received a $3000 bill for the ambulance ride. My insurance wouldn't cover it because, since I didn't stay overnight, it obviously wasn't necessary. They told me I shouldn't have called the ambulance....but I didn't call, I was passed out on the ground.