Continuity mistake: Mark is intubating the man who is paralyzed from the neck down. We can see his hands working - we know it is him by the splint on his wrist and he is talking as he works. However, Malik comes in and calls him away, and he rushes off, but the hands working on the patient don't change.
Of Past Regret and Future Fear - S4-E20
Continuity mistake: As Carter's grandmother is asking him if he'll be at his grandfather's dinner, we see him pick up a mug by its handle - but the next shot, from behind his shoulder, shows him holding the mug by the side.
Continuity mistake: Just before Peter bends over beside Reese, an extra is starting to walk behind them. The next shot shows the cereal on Peter's head and we should be able to still see the extra, but there's no sign of him.
Continuity mistake: At the beginning of the show, Doug is working on the computer while Mark is talking to him. At first there is a document sitting on top of a thick black book but that disappears after a couple of shots - and neither of them touched it.
Continuity mistake: During the last 2 minutes, Jerry is patronizing Dr. Waver. As he walks away, you see Dr. Greene (who has not been in this episode until now) walk across the hall in the background. A few moments later, outside, after Dr. Carter finishes chatting with the fire chief, he bumps into Dr. Greene outside. Dr. Greene is on his way in for his shift starting in 5 minutes and explains that he is coming straight from the airport. (00:43:22 - 00:44:50)
Answer: Take care of your dad.