Effect Of Dexmedetomidine on Intracranial Pressure in Gynecological Laparoscopic Surgeries: Ultrasonographic Evaluation of Optic Nerve Sheath Diameter

Laparoscopy is a minimally invasive surgical procedure used in gynecology for both diagnostic and treatment purposes. During gynaecologic laparoscopy, the patient is placed in the Trendelenburg position to optimise visualization and access to the pelvis, so this study was done to investigate the effect of dexmedetomidine on changes in intracranial pressure reflected as optic nerve sheath diameter (ONSD) during gynecological laparoscopic surgery in the Trendelenburg position by ultrasonographic evaluation. This study included 76 female patients who underwent elective therapeutic gynecological laparoscopic surgeries. Patients were randomly divided into two groups: group D (dexmedetomidine group, n=38) received dexmedetomidine loading (one mcg/kg) for ten minutes (min) and infusion (0.4 mcg/kg/h for one hour), and group P (placebo group, n=38) received 0.9% normal saline loading (2.5 ml/10 kg) and infusion (one ml/10 kg/h for one hour), started 10 min before induction of anesthesia and continued for one hour. Optic nerve sheath diameter was taken after application of a high-frequency linear probe on closed eyelids and measured at three mm behind the acoustic shadow of the vitreous body. Results showed that during follow-up periods (15 minutes to 3 hours), group D showed a significant reduction in heart rates compared to group P at all-time points (p<0.05). Group D showed significantly lower blood pressure (BP) compared to group P at 45 minutes, one hour, 1.5 hours, two hours, and 2.5 hours. There were significantly lower values of ONSD in group D after the Trendelenburg position. So, dexmedetomidine in the studied doses effectively reduces ONSD in cases undergoing gynecological laparoscopic surgery in the Trendelenburg position, which may reflect a reduction in intracranial pressure (ICP) elevation and was associated with notable hemodynamic stability.