Inclusion Criteria:  Age ≥ 18 Elective open gynecological surgery American Society of Anaesthesiologists physical status classification 1-3  Exclusion Criteria:  Laparoscopic surgery or robot-assisted surgery Patients who had analgesic agents, anti-psychotic agents, anticonvulsants which were related to chronic pain Patients who had hypersensitivity to analgesic agents or medications related anesthesia. Patients who were required to have mechanical ventilation after surgery Patients who had arrhythmia Patients who transferred to the surgical intensive care unit immediately after surgery Pregnancy