The following story was submitted to me by an EMT friend of mine by the name of Jeremy Shocker. He swears it's true.
You see, it was about thirty years ago and I was a young EMT and we had to confirm a patient was dead in three different leads. We had to confirm a flat line in three leads. It never made any sense, but that's what we did even up to the 2000s. I mean, most people you just look at them and you can see they're dead. You see a person the color of purple in rigor mortis and you can't call them dead until you confirmed it in three leads. So one day I confirmed two leads on the person, and the third time I put the leads on a tomato. About this time we arrived at the hospital still doing CPR on the patient. The doctor came out and met us in the ambulance, and based on the third rhythm (yes, the one we did on a tomato) he said, "That looks like fine V-Fib. We should probably continue working him up." This confirmed two things for me. One, some doctors don't know how to take a joke. Two, to keep a tomato alive you must do CPR.