Intraocular Pressure Changes During EGD

Overview

This prospective observational study evaluates short-term changes in intraocular pressure (IOP) during elective esophagogastroduodenoscopy (EGD) performed under routine sedation. IOP is measured bilaterally using a handheld rebound tonometer (Icare IC200) at four predefined procedural time points: baseline in the sitting position (T0), after routine administration of 500 mL isotonic intravenous fluid in the sitting position (T1), after sedation in the left lateral decubitus position before endoscopy (T2), and when the endoscope reaches the second portion of the duodenum (T3). The primary outcome is the within-subject change in IOP across these procedural stages. Secondary analyses include differences between the dependent and non-dependent eyes in the left lateral decubitus position and exploratory assessment of factors associated with the change in left-eye IOP from baseline to duodenal passage. No study-specific intervention or treatment allocation is performed; all clinical procedures follow routine institutional practice.

This single-center, prospective observational cohort study was conducted at Elazig Fethi Sekin City Hospital, Türkiye, in adults (≥18 years) undergoing elective esophagogastroduodenoscopy (EGD) under routine sedation. Consecutive patients were screened for eligibility. Exclusion criteria included glaucoma or ocular hypertension, corneal disease affecting intraocular pressure (IOP) or corneal thickness measurements, ocular infection, severe dry eye disease, hemodynamic instability, heart failure, renal failure, cirrhosis or other conditions contraindicating fluid loading, use of topical ocular medications, and previous ocular surgery or refractive laser procedures. After venous access was established, baseline central corneal thickness and bilateral IOP were measured. As part of routine institutional practice, patients received 500 mL of 0.9% NaCl intravenously over approximately 10-15 minutes before sedation. This fluid administration was not assigned as a study-specific experimental intervention. Sedation was administered as part of routine clinical care using midazolam 0.02 mg/kg IV and propofol 0.5 mg/kg IV, with additional 10-20 mg propofol boluses as clinically required. Spontaneous breathing was maintained, supplemental oxygen was administered by nasal cannula, and noninvasive blood pressure, cardiac rhythm, and peripheral oxygen saturation were continuously monitored. Intraocular pressure was measured bilaterally using a handheld rebound tonometer (Icare IC200) at four predefined procedural time points: T0, baseline before fluid administration and sedation in the sitting position; T1, after administration of 500 mL isotonic fluid in the sitting position; T2, after sedation in the left lateral decubitus position and before endoscopy; and T3, when the endoscope reached the second portion of the duodenum while the patient remained in the left lateral decubitus position. The primary outcome was the within-subject change in IOP across T0-T3. Secondary analyses included paired comparison of the dependent and non-dependent eyes at T2 and T3 and exploratory multivariable analysis of factors associated with the change in left-eye IOP from baseline to duodenal passage (T3-T0). Repeated-measures analyses were used to evaluate changes over time. No study-specific intervention or treatment allocation was performed; all clinical procedures were conducted according to routine institutional practice. Forty-seven participants with complete IOP measurements at all predefined time points were included in the final analysis.