GREY'S ANATOMY - "State of Love and Trust" - As Derek begins his role as interim chief, he faces a potential lawsuit when Bailey and Meredith's patient awakens from anesthesia mid-surgery. Meanwhile, Teddy refuses to place Cristina on her service, as Arizona tests Alex out in Pediatrics, and Mark refuses to speak to a heartbroken Lexie, on "Grey's Anatomy," THURSDAY, FEBRUARY 4 (9:00-10:01 p.m., ET) on the ABC Television Network. (ABC/ADAM LARKEY) KIM RAVER, KEVIN MCKIDD