Intraocular Pressure Changes During EGD

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.

Inclusion criteria

• Age ≥18 years
• Scheduled for elective esophagogastroduodenoscopy (EGD)
• Acceptance of the procedure under sedation
• Ability to cooperate with intraocular pressure (IOP) and central corneal thickness (CCT) measurements

Exclusion criteria

• Diagnosis of glaucoma or ocular hypertension
• Corneal diseases that could affect intraocular pressure or central corneal thickness measurements
• Ocular infection
• Severe dry eye disease
• Hemodynamic instability
• Heart failure
• Renal failure
• Cirrhosis or other clinical conditions contraindicating fluid loading
• Use of topical ocular medications, including antiglaucoma drugs or topical steroids
• History of ocular surgery
• History of refractive laser procedures