The Impact of Steep Trendelenburg Position on Intraocular Pressure.

Intraocular pressure occurring during the Trendelenburg position may be a risk for postoperative visual loss and other ocular complications. Intraocular pressure (IOP) higher than 21 mmHg poses a risk for ocular impairment causing several conditions such as glaucoma, detached retina, and postoperative vision loss. Many factors might play a role in IOP increase, like peak expiratory pressure (PIP), mean arterial blood pressure (MAP), end-tidal CO (ETCO) and surgical duration and some others (anaesthetic and neuromuscular blockade depth) contribute by reducing IOP during procedures requiring both pneumoperitoneum and steep Trendelenburg position (25-45° head-down tilt). Despite transient visual field loss after surgery, no signs of ischemia or changes to the retinal nerve fibre layer (RNFL) have been shown after surgery. Over the years, several studies have been conducted to control and prevent IOPs intraoperative increase. Multiple strategies have been proposed by different authors over the years to reduce IOP during laparoscopic procedures, especially those involving steep Trendelenburg positions such as robot-assisted laparoscopic prostatectomy (RALP), and abdominal and pelvic procedures. These strategies included both positional and pharmacological strategies.