Inclusion Criteria:  ASA I-II-III risk group Patients who underwent gynecological surgery under general anesthesia, who underwent erector spina block, and whose pain was followed by analgesia nociception index or conventional methods for intraoperative pain monitoring Patients whose informed consent was read and consent was obtained from them and their guardians  Exclusion Criteria:  cardiac rhythm disorder central-autonomic nervous system disease neuropsychiatric disease receiving opioid therapy Use of drugs that will affect cardiac autonomic regulation Known allergy to the drugs to be applied Contraindicated for ESP block Patients who do not agree to participate in the study will not be included in the study. Patients who were administered drugs to stabilize the patient's hemodynamics during the operation