Continuity mistake: As the janitor hugs Carla, he picks her up and you see part of her hair gets caught on her cheek. When the shot changes its all suddenly pushed back. The following shot it goes back to halfway down her cheek.
Continuity mistake: Near the end after JD tells the interns he wants them all to wave, they all start waving their arms. The shot cuts to a different view and Rex's hands are instantly back on the table.
Answer: Dan was drinking beer and Cox feared that Dan might get so intoxicated he would fall asleep and drown in the tub.
Mortug