Effects of Videolaryngoscope on Intraocular Pressure

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

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02474394

Enrollment

Registered

2015-06-17

Start date

2013-02-28

Completion date

2015-06-30

Last updated

2015-06-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Intubation Complication

Brief summary

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

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.

Interventions

DEVICEMcgrath

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

DEVICEMacintosh

The patient will be intubated using Macintosh laryngoscope and the intraocular pressure of the patient will be evaluated with Tonopen XL tonometer

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

SCREENING

Masking

DOUBLE (Subject, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 60 Years

Healthy volunteers

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

Design outcomes

Primary

Measure	Time frame	Description
Intraocular pressure	during laryngoscopy	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.

Countries

Turkey (Türkiye)

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026