The Effect of Optic Nerve Diameter on Postoperative Cognitive Function in Laparoscopic Hysterectomy

Prospective study, 40 patients ASA 2-3, 30-75 years old who were planned for laparoscopic hysterectomy operation will be included.One day before the operation and postoperative 1.3.7. A mini mental assessment test will be performed on these days.Standard monitoring and Near-Infrared Spectroscopy monitoring to measure cerebral oxygen saturation will be performed on the patients.NIRS sensors will be placed on the right and left sides of the forehead, 2 cm above the eyebrow, before induction of anesthesia. Before the induction of anesthesia, the measurement will begin and the FiO2 (fraction of inspiration oxygen) will be kept at 60%.General anesthesia induction will be made with propofol 2mg/kg, remifentanil 0.5 µg/kg and rocuronium 0.6mg/kg, and maintenance will be provided with 2% sevoflurane.The patient will be intubated and ventilation support will be provided so that the tidal volume is 6-8 ml/kg and the end tidal CO2 is 30-40 mmHg. PEEP (Positive end expiratory pressure) will not be applied to any patient. Intra-abdominal pressure will be maintained at 15 mmHg. All patients will be given 1gr paracetamol and 100mg tramadol for postoperative analgesia.During the measurement of optic nerve diameter, a layer of sterile water-soluble gel will be applied on the closed eyelid with a linear 10-5 MHz ultrasound probe. In our study, ONSDs of all patients will be measured by the same experienced anesthetist. Measurements will be made at 5 different times. 5 minutes after induction of anesthesia in the supine position (T0), 5 minutes after the onset of pneumoperitoneum (T1), 5 minutes after the upright trendelenburg position (T2), at the 2nd hour of the trendelenburg position (T3) and 5 minutes after returning to the supine position at the end of the surgery (T4) .ONSD measurements of the patients measured at 5 different times, peroperative NIRS values, peroperative SpO2, mean blood pressure, peak heart rate, anesthesia time, surgery time, time to stay in the trendelenburg p