Different Intraperitoneal Pressures on Optic Nerve Sheath Diameter in Laparoscopic Surgeries

Gynecological surgeries are minimally invasive procedures. The establishment of pneumoperitoneum, special patient positioning, and surgical stimulation can induce a stress response in patients. Carbon dioxide (CO₂) pneumoperitoneum and the Trendelenburg position lead to increases in intra-abdominal, intrathoracic, and airway pressures, which in turn may directly or indirectly cause elevations in intracranial and intraocular pressures. During the perioperative period, the optic nerve sheath diameter (ONSD), measured ultrasonographically, is used as a reliable method to estimate intracranial pressure (ICP). Monitoring ICP under anesthesia may help prevent neurological complications such as neurological deterioration and optic neuropathy. Furthermore, studies have demonstrated ICP changes in robotic and laparoscopic gynecologic surgeries through ultrasonographic measurement of ONSD. Traditionally, laparoscopic abdominal surgeries are performed using intraperitoneal pressures ranging between 10 and 18 mmHg. Lower intra-abdominal pressures have been associated with reduced postoperative pain, improved pulmonary parameters, and a decreased risk of gas embolism. However, the data on these outcomes remain limited. In this study, we aimed to investigate the effect of pressures above and below 12 mmHg on the optic nerve sheath diameter-and consequently on intracranial pressure-in patients undergoing laparoscopic gynecologic surgery.