I had a week of jury duty once, and must have had to state my profession about 20 times during the different voir dires. So plenty of people knew I was a nurse. One morning in the jury room, someone ran in and grabbed me, saying I had to come downstairs right then. I found a woman on the floor, out cold. I made sure the heroes were on the way, and kept asking if anyone knew anything about her. Finally a little boy said that she was his mama, and she had "the sugar." I had no glucometer, so I basically held her head in my lap until EMS got there. Her fingerstick bs was over 300 when they first checked it.
One day driving home from work I saw an elderly man lying on the grass beside the road, with a man I thought was a firefighter beside him, but no ambulance or fire truck. I pulled over and the guy in uniform practical gibbered he was so nervous. I thought this was very weird, he's the firefighter, but no, he was actually a city inspector! He had called 911, so I just did a basic neuro check and took the guy's pulse. He was confused, diaphoretic, and had a pulse of 180. Turns out, he'd gotten tired of waiting on his wife in the doctor's office, and had decided to walk in 100+ temperatures. He'd made it several miles before he collapsed. I kept the elderly man calm and on the ground (he kept saying he was going to walk home) until the ambulance got there, but that was the extent of what I could do.