Anesthesia on Optic Nerve Sheath Diameter

Study Overview
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Brief Summary
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Different amounts of anesthetic gas can be used in the obstetric gynecological surgery operations to be performed with open method. Researchers aimed to compare the effect of gas changes on intraocular nerve diameter by ultrasonography.

Detailed Description
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A total of 80 patients who underwent laparotomic gynecological surgery were divided into two groups prospectively: high flow of 2 L/min and minimal flow of 0.5 L/min. Anesthesia was maintained with 50% oxygen-50% air at 2 L/min and desflurane at 1.1 MAC in Group 1 (n=40) and with 50% oxygen-50% air at 2 L/min and desflurane at 1.1 MAC in Group 2 (n=40). After 10-15 minutes, group 2 was administered minimal flow with 50-60% oxygen-40-50% air at 0.5 L/min and desflurane, and 10 minutes before the end of the surgery, the patients were switched to high flow with 50% oxygen-50% air at 2 L/min.

Official Title
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The Effect Of Minimal and High Flow Anesthesia on Optic Nerve Sheath Diameter in Laparotomic Gynecological Surgery

Conditions
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Optic Nerve Sheath Diameter

Intervention / Treatment
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* Procedure: The Effect Of Minimal and High Flow Anesthesia on Optic Nerve Sheath Diamater


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 18-65 years ASA I-II Who underwent laparotomic gynecological surgery Exclusion Criteria: Patients with obstructive pulmonary disease Patients with decompensated diabetes, those with a fasting period of more than 12 hours -Acute alcohol intoxication Chronic alcohol use Who refuse to participate in the study Who are not cooperative, do not speak Turkish Who had known eye disease (glaucoma, retinal detachment), had a previous history of eye surgery, Increased intracranial pressure findings (intracranial lesion, previous cerebrovascular diseases Body mass index of > 40kg/m2 ASA > III

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: A total of 80 patients who underwent laparotomic gynecological surgery were divided into two groups prospectively: high flow of 2 L/min and minimal flow of 0.5 L/min. Anesthesia was maintained with 50% oxygen-50% air at 2 L/min and desflurane at 1.1 MAC in Group 1 (n=40) and with 50% oxygen-50% air at 2 L/min and desflurane at 1.1 MAC in Group 2 (n=40). After 10-15 minutes, group 2 was administered minimal flow with 50-60% oxygen-40-50% air at 0.5 L/min and desflurane, and 10 minutes before the end of the surgery, the patients were switched to high flow with 50% oxygen-50% air at 2 L/min.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: High Flow Anesthesia, Low Flow Anesthesia<br>. The patients were randomly allocated to one of the two groups of fresh gas flows using the closed-envelope technique: 2 L/min high flow and 0.5 L/min minimal flow. Group 1 (n = 40) was operated under high flow anesthesia with 50% O2 - 50% air at 2 L/min and desflurane at 1.1 MAC for the duration of the surgery. For anesthesia maintenance, Group 2 (n=40) was administered 50% oxygen - 50% air at 2 L/min and desflurane for 10-15 minutes. After reaching 1.1 MAC, it was switched to minimal flow with 50-60% oxygen- 40-50% air at 0.5 L/min and desflurane. 10 minutes before the end of the surgery, it was switched to high flow with 50% oxygen -50% air at 2 L/min. | Procedure: The Effect Of Minimal and High Flow Anesthesia on Optic Nerve Sheath Diamater<br>* The patients were randomly allocated to one of the two groups of fresh gas flows using the closed-envelope technique: 2 L/min high flow and 0.5 L/min minimal flow.<br>|
| Active Comparator: Peroperetive Optic Nerve Sheath Diameter<br>Optic nerve sheath diameter measurements were performed by an experienced and the same anesthetist. In the measurements, the GE Healthcare Logiq e series USG device and 12-MHz linear probe were used. Longitudinal and transverse axis images were obtained on both eyelids while the patient was in the supine position. Measurements were taken 3 mm behind the optic nerve head | Procedure: The Effect Of Minimal and High Flow Anesthesia on Optic Nerve Sheath Diamater<br>* The patients were randomly allocated to one of the two groups of fresh gas flows using the closed-envelope technique: 2 L/min high flow and 0.5 L/min minimal flow.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Optic Nerve Sheath Diamater | Optic nerve sheath diamater measurements of the patients were recorded before and during the surgery at specified time points (T0: awake, T1: High fresh gas flow after induction at the 10th min., T2: Inhalation anesthesia at the 30th min., T3: Inhalation anesthesia at the 60th min., T4: Inhalation anesthesia at the 90th min., T5: Before extubation).A typical optic nerve sheath is generally less than 5 mm in diameter, and diameters greater than 5.5 mm predict an ICP of ≥20 cm H2O with 100% sensitivity and specifity | 2 hours operation time | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peroperative Complications | Complications during the surgery (decreased oxygen levels, hypercapnia, hypotension, hypertension, bradycardia, tachycardia, rhythm disorders) were recorded. | 2 hours operation time | 
| Postoperative Complications | Complications in the recovery room (respiratory distress, decreased oxygen levels, hypotension, hypertension, bradycardia, tachycardia, vomiting, rhythm disorders) were recorded. | postop 20 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Minimal Flow Anesthesia, Optic Nerve Sheath Diameter