Additional actors were ready to improvise if something went wrong (forgotten dialogue or technical problems). Fortunately, they was never used.
Goof: Towards the end of the East Coast version of this episode, you can see Kerry Weaver walking without her crutch.
When the title is shown at the beginning of the episode, it reads "ambush," without the first letter being capitalized.
Aggie: When did you decide to become a surgeon?
Elizabeth: Well, that gets into pleasing my father, rattling my mother... and all sorts of boring family secrets. The short answer is, my father is a surgeon, as was his father. And my father had no sons.
Carol: (to the reporters) Actually, it's a myth about doctors and nurses dating so much. I mean, more nurses date cops, firemen, paramedics. Now, that cliché is true.
Connie: Especially cops.
Chuny: Especially young cops.
Corday: Dr. Benton?
Corday: Elizabeth Corday. Visiting surgical lecturer and your saviour.
Benton: Ah, excuse me?
Corday: Well, I hear you've been on call forever. You're free to go. I'm on now.
Greene: Probably the best part of my job is that sometimes, working here, you can repair some of the violence. Some of the bad things that happen to people. Not always. We couldn't do much for that guy who was paralyzed. Probably on a vent for the rest of his life. I guess we did save the kid that he was trying to help. So his sacrifice wasn't for nothing. And yes, I was attacked myself right here in this very hospital. They haven't been able to catch the guy who did it, or at least, they haven't been able to charge anyone. The worst thing about it isn't what it did to me. The worst thing is that it meant that some of the world's violence has leaked into our own ER. This is meant to be a safe place for fixing people. Now it's vulnerable. And as an ER doctor, that's hard to accept.
Aggie: It sounds frightening. Are you scared?
Greene: Sure. Of, uh, losing control.
Aggie: Control of what's outside?
Greene: And what's in me. (long pause) Is that enough?
Greene: Then turn it off!
Corday: They said there was an adolescent who decompensated.
Hathaway: Oh, Dr. Benton took him up.
Corday: Ah, Dr. Benton. You call your surgeons "doctor." Well, I suppose "Miss Corday" won't get me very far around here.
Hathaway: Well, just to the waiting room.
Ross: What is all this about cops and firemen?
Hathaway: (gasps) Jealous?
Ross: Jealous. I just wanna know what you're doin for them that you're not doin for me.
Hathaway: Uh, I'll tell you later if you bring the cuffs.
Ross: Yeah, I thought I was gonna get some sleep tonight.
Hathaway: Oh, don't count on that.
Ross: Buddy, you look like a star out there.
Greene: Well, I'm enjoying the attention.
Ross: Well, don't get too used to everybody taking orders from you.
Greene: Yeah, I was hoping for a sequel.
Chuny: I don't know. But, the best one was the guy with the transistor radio. Remember?
Conni: Right. He said he was getting out of the shower and he slipped and he sat down on it.
Carol: While it was still playing?
Malik: Whoop. There it is.
Chuny: So I asked Mark - Dr. Greene if he was going to extract the foreign body and he said, "No. But I think I'll tune it to the ball game."
Stuart: Dr. Carter, our mic will pick you up at normal volume. You can relax and speak naturally.
Greene: Carter wasn't acting. He's really like that.
Carter: (to Justin Chang) If you vomit in the OR, you could aspirate your stomach contents into your lungs, develop pneumonia.
Greene: That's probably more than Mr. Chang needed to hear.
Carter: Good evening.
Greene: Dr. Carter, you're early.
Carter: Open fracture?
Carter: You need me?
Ross: Uh, yes, actually. I'm sick of assisting Dr. Welby here.
(Greene and Ross are treating Justin Chang's broken leg)
Justin: So, I really broke it, huh?
Ross: Well, you're not going to be playing varsity this fall.
Justin: Varsity? I'm 24 years old.
Ross: You're 24?
Greene: Guess I don't need a pediatrician.
Ross:(to Justin) You are gonna be carded until you're 40.
This episode did not have any opening credits.
The West Coast version of the live episode appears on the Season 4 DVD.
The episode won an Emmy Award for Outstanding Technical Direction/Camera/Video for a Series. It was nominated for Outstanding Lighting Direction (Electronic) for a Drama Series, Variety Series, Miniseries, Movie or a Special, Outstanding Sound Mixing for a Drama Series, and Outstanding Directing for a Drama Series (Thomas Schlamme).
When aired in syndication, the first half of the episode is the East Coast version, and the second half of the episode is the West Coast version.
The Cubs-Astros baseball game that Doug Ross watches in the break room was being broadcast live that night on WGN.
This episode was broadcast live. The cast performed it twice, once for the East Coast airing and three hours later for the West Coast airing.
Doug: (to Carol) Lucy, you got some 'splaining to do...
Doug is making a reference to one of the signature lines used by Desi Arnaz's character, Ricky Ricardo, in the 1950s comedy series I Love Lucy.