Effect Of Trendelenburg Position And Pneumoperitoneum On Optic Nerve Sheath Diameter In Robot-Assisted Prostatectomy

Robot-assisted laparoscopic radical prostatectomy requires steep Trendelenburg positioning and carbon dioxide pneumoperitoneum to improve the surgical field. These conditions may lead to increased intracranial pressure due to venous congestion and elevated intrathoracic pressure. Optic nerve sheath diameter measurement by ultrasonography is a noninvasive method that can be used to estimate changes in intracranial pressure during surgery.

In this prospective study, patients undergoing robot-assisted laparoscopic radical prostatectomy will be compared with patients undergoing open radical prostatectomy. Optic nerve sheath diameter will be measured at predefined time points during surgery using ocular ultrasonography. Hemodynamic parameters, respiratory variables, intra-abdominal pressure, duration of surgery, blood loss, and administered fluids will also be recorded.

The aim of this study is to evaluate the effect of pneumoperitoneum and steep Trendelenburg position on optic nerve sheath diameter and to determine the relationship between optic nerve sheath diameter and intraoperative physiological changes.

Inclusion criteria

• Age ≥ 18 years
• ASA physical status I-III
• Patients scheduled for robot-assisted laparoscopic radical prostatectomy or open radical prostatectomy under general anesthesia
• Written informed consent obtained

Exclusion criteria

• History of intracranial surgery or intracranial lesion
• Known ocular disease (glaucoma, retinal detachment, diabetic retinopathy, previous ocular surgery, etc.)
• Intraocular pressure greater than 30 mmHg
• Refusal to participate in the study