Other mistake: Season 12, Episode "Blame it on the Rain": At the beginning of the episode, Abby is almost run over by a man driving an SUV. They exchange words and then Abby throws a supposedly full cup of coffee at him. The cup of coffee bounces off the seat of the man's car and it is obvious that the cup is empty.
Other mistake: When Jodi O'Brien is having seizures during the birth, Dr. Greene decides to take the baby out prematurely. Complications result and the woman dies, they show a shot of a clock in the background and it says 7:00, but when they say the time of death they say 6:02.
Other mistake: When the patient Isadore is brought in, early in the show, he is transferred from the stretcher onto a table, and we can see him deliberately move his right hand out of the way of the other actors moving him. He is supposed to be unconscious and very seriously injured so would not have done this is real life.
Other mistake: When Doug and the nurses are watching the TV about a motorcycle accident, Kerry comes along and calls him Mark. This could be a character error, but as Doug responds 'yeah', and they talk, it indeed becomes a production error. In real life, the person would have corrected her.
Other mistake: In the opening sequence, there is an aerial shot where the camera pans over Central Park in New York City. The trees are full of leaves and some are changing color. The problem is that it is February when this episode is taking place, and the trees would have no leaves left on them.