Intraocular Pressure and Optic Nerve Sheath Diameter Changes in Laparoscopic Cholecystectomies

Study Overview
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Brief Summary
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Pneumoperitoneum created during laparoscopic surgeries has some effects on human physiology. Increased intraabdominal pressure results in increased intrathoracic pressure, and eventually may result in increased intracranial and intraocular pressures. In this study we aimed to identify intraocular and intracranial pressure changes during the perioperative period due to the pneumoperitoneum created for laparoscopic cholecystectomy surgeries. Intraocular pressure will be measured directly from the eye. Intracranial pressure will be estimated by measuring optic nerve sheath diameter changes ultrasonographically.

Official Title
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Intraocular Pressure and Optic Nerve Sheath Diameter Changes in Laparoscopic Cholecystectomies

Conditions
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Intraocular Pressure, Intracranial Pressure, Pneumoperitoneum

Intervention / Treatment
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* Diagnostic Test: Intraocular pressure measurement via ocular tonometry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing laparoscopic cholecystectomy American Society of Anesthesiologists (ASA) 1 or 2 physical status patients Elective surgeries Exclusion Criteria: Patients with glaucoma ASA 3 or above patients Emergency surgeries

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Intraocular pressure measurement via ocular tonometry|Intraocular pressure and optic nerve sheath diameter changes of the patients undergoing laparoscopic cholecystectomy will be measured throughout the surgery at different times using ocular tonometry and ultrasound, respectively.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure | The normal physiological value for intraocular pressure is 10-20 mm Hg. It is affected by pneumoperitoneum created for laparoscopy. The pressure will be measured via ocular tonometry through the eye during the surgery at predetermined time intervals. | Throughout the operation (usually about 1 hour). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intracranial pressure | The normal physiological value for intracranial pressure is below 10 mm Hg. It is affected by pneumoperitoneum created for laparoscopy. The pressure will be estimated through changes in the optic nerve sheath diameter which will be measured by ultrasonography through the eye during the surgery at predetermined time intervals. | Throughout the operation (usually about 1 hour). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Intraocular pressure, Optic nerve sheath diameter, Pneumoperitoneum, Laparoscopy, Laparoscopic surgery