Effects of Videolaryngoscope on Intraocular Pressure

Study Overview
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Brief Summary
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This study is designed to compare the effects of the McGrath Series 5 video laryngoscope and Macintosh laryngoscope on intraocular pressure during laryngoscopy.

Detailed Description
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The stability of the intraocular pressure plays an important role during ophthalmic surgery. The systemic blood pressure, aqueous humor dynamics, choroidal blood volume, central venous pressure, extra-ocular muscle tone, and also conventional laryngoscopy affect the intraocular pressure.It was shown that the new devices for laryngoscopy, such as video laryngoscopes provide minimal hemodynamic changes when compared to direct laryngoscopes. However there is no current data about the effects of the intubation with McGrath videolaryngoscope on intraocular pressure. The main objective of this study to compare the effects of the McGrath Series 5 video laryngoscope and Macintosh laryngoscope on intraocular pressure during laryngoscopy.

Official Title
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The Comparison of the Effects of McGrath Video Laryngoscope and the Macintosh Laryngoscope on Intraocular Pressure: A Randomized Trial

Conditions
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Intubation Complication

Intervention / Treatment
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* Device: Mcgrath
* Device: Macintosh


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American society of anesthesiologist physical status I Non-ophthalmic elective surgery under general anesthesia Exclusion Criteria: A history of pre-existing glaucoma or previous intraocular surgery Thyromental distance below 6cm Maximum mouth opening below 3cm Mallampati score of III or IV Pre-anesthetic intraocular pressure above 20 mmHg Number of intubation attempts more than 2 Obstetric or laparoscopic surgery

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 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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Design Details

Primary Purpose: Screening
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Mcgrath<br>The endotracheal intubation will be provided using Mcgrath series 5 video laryngoscope | Device: Mcgrath<br>* The patient will be intubated using McGrath series 5 video laryngoscope and the intraocular pressure of the patient will be evaluated with Tonopen XL tonometer<br>* Other names: videolaryngoscope;|
| Active Comparator: Macintosh<br>The endotracheal incubation will be provided using macintosh laryngoscope | Device: Macintosh<br>* The patient will be intubated using Macintosh laryngoscope and the intraocular pressure of the patient will be evaluated with Tonopen XL tonometer<br>* Other names: Conventional Laryngoscope;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure | The intraocular pressure measurement will be performed using a Tono-Pen XL tonometer (Reichert Inc., USA) by an ophthalmologist who is blind to the intubation device used. | during laryngoscopy |