When Judith Light's character is in the surgery, she's wearing a scarf on her head. The scene cuts away to Cool's point of view, looking into the window, and she is bare headed. Then the scene is back in the surgery and the scarf is back on her head.
When Dr Westphall enters the OR to talk to Mrs Lonniker, he dons an industrial dust/pollen mask (the kind that someone might wear to install insulation or mow lawns). The error is particularly obvious, because everyone else in the surgical suite is wearing appropriate surgical masks.