Continuity: Episode 3.09, "From a Whisper to a Scream": During the operation on the Asian girl from the market, a stitch breaks and Cristina is covered with spurting blood, including all over her mask. When she turns to leave the OR, the all-over splatter on her mask has turned to what looks more like dribbles from an eye dropper (most likely an attempt to recreate the mess for another take), and there's about half as much of it as before.