Optic Nerve Sheath Diameter in Laparoscopic Surgeries During Trendelenburg Position

Study Overview
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Brief Summary
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It is difficult to measure the several levels of intracranial pressure during abdominal surgery, and direct monitoring with intracranial devices is often impossible. Measurement of optic nerve sheath diameter (ONSD) via ultrasonography has been developed as an alternative method for evaluating intracranial pressure. Increased intracranial pressure may cause in expanding of the optic nerve sheath and may increase the diameter. Therefore, measuring the diameter of the optic nerve sheath via ultrasonography is considered as a non-invasive, easy-to-apply and reliable method to evaluate intracranial pressure.

Detailed Description
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The peritoneum is inflated with carbon dioxide (insufflation) and head-down position is performed (Trendelenburg) during laparoscopic colon and gynecologic surgeries. Intracranial pressure (ICP) may be affected by positive intraabdominal pressure due to pneumoperitoneum. The Trendelenburg position (usually at a degree of 25-400) causes increasing in the pressure of cerebrospinal fluid during surgery. Therefore, cerebral edema and an increasing in ICP may occur. It is difficult to measure the several levels of intracranial pressure during abdominal surgery, and direct monitoring with intracranial devices is often impossible. Measurement of optic nerve sheath diameter (ONSD) via ultrasonography has been developed as an alternative method for evaluating intracranial pressure. The optic nerve is an extension of the central nervous system, surrounded by cerebrospinal fluid (CSF) and continues with the nerve sheath. Increased intracranial pressure may cause in expanding of the optic nerve sheath and may increase the diameter. Therefore, measuring the diameter of the optic nerve sheath via ultrasonography is considered as a non-invasive, easy-to-apply and reliable method to evaluate intracranial pressure. In this study, we aimed to evaluate the changes of optic nerve sheath diameter in patients who will undergo laparoscopic colon and gynecologic surgery during trendelenburg position. Our primary goal is to compare the optic nerve sheath diameters via ultrasonography, and our secondary aim is to evaluate the effect of this change on intracranial pressure.

Official Title
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The Evaluation of Optic Nerve Sheath Diameter in Patients Underwent Laparoscopic Colon and Gynecologic Surgeries During Trendelenburg Position.

Conditions
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Colon Disease, Gynecologic Disease

Intervention / Treatment
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* Other: Optic nerve sheath diameter


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists (ASA) classification I-II Scheduled for laparoscopic colon and gynecologic surgeries under general anesthesia Exclusion Criteria: use of beta blocker or diuretic drugs severe heart failure diabetes with ocular or neurologic complications history of cardiac, eye, intracranial, and thoracic surgery history of hydrocephalus, glocoma, intracranial tumor, cerebrovascular disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Optic nerve sheath diameter|Pre and post-trendelenburg optic nerve sheath diameter will be measured|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Optic nerve sheath diameter | Pre and post-trendelenburg diameters of optic nerve sheath | Change from baseline optic nerve sheath diameter at 10 mins and 60 mins after trendelenburg. And 10 minutes after the re-neutral position | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Trendelenburg position, Optic nerve sheath diameter, Colon surgery, Gynecologic surgery