Anesthesiology is a medical specialty that focuses on pain relief, unconsciousness and lack of awareness during surgery. Anesthesiologists function to care for patients before, during and after the completion of an operation. This care has resulted in anesthesiologists being referred to as the "perioperative doctor" (providing care "around" the surgery). The anesthesiologist is responsible for the supervision and care of patients in post anesthesia care units (recovery rooms).