Remifentanil vs Esmolol During Intubation for Cerebral Aneurysm Coil Embolization

June 16, 2026 updated by: Fatih Sultan Mehmet Training and Research Hospital

Effects of Remifentanil Versus Esmolol on Optic Nerve Sheath Diameter/Eyeball Transverse Diameter Ratio During Endotracheal Intubation in Patients Undergoing Cerebral Aneurysm Coil Embolization: A Randomized Controlled Trial

Endotracheal intubation may cause significant increases in blood pressure, heart rate, and intracranial pressure, particularly in patients undergoing cerebral aneurysm coil embolization. Remifentanil and esmolol are commonly used agents to attenuate these responses during anesthesia induction.

This randomized controlled trial aims to compare the effects of remifentanil and esmolol administered before endotracheal intubation on optic nerve sheath diameter/eyeball transverse diameter ratio (ONSD/ETD), a noninvasive surrogate marker of intracranial pressure, as well as hemodynamic responses in patients undergoing elective cerebral aneurysm coil embolization.

The findings may help identify the most effective strategy for minimizing intubation-related intracranial pressure changes and hemodynamic fluctuations in neurointerventional anesthesia practice.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

Endotracheal intubation is one of the most stimulating periods during induction of general anesthesia and is associated with transient increases in blood pressure, heart rate, and intracranial pressure. These responses may be particularly important in patients undergoing cerebral aneurysm coil embolization, where excessive hemodynamic fluctuations and increases in intracranial pressure may adversely affect procedural safety.

Optic nerve sheath diameter (ONSD) measured by ultrasonography has emerged as a noninvasive marker of intracranial pressure. The optic nerve sheath diameter-to-eyeball transverse diameter ratio (ONSD/ETD) has been proposed as a more standardized parameter that may reduce interindividual variability.

Remifentanil and esmolol are widely used agents for attenuation of the hemodynamic response to endotracheal intubation. Although both agents have been shown to reduce sympathetic activation during airway manipulation, their comparative effects on ONSD/ETD ratio and intubation-related intracranial pressure changes in patients undergoing neurointerventional procedures remain unclear.

The aim of this prospective randomized controlled trial is to compare the effects of remifentanil and esmolol administered before endotracheal intubation on ONSD/ETD ratio and hemodynamic parameters in adult patients undergoing elective cerebral aneurysm coil embolization. Participants will be randomized in a 1:1 ratio to receive either remifentanil (0.5-1 µg/kg IV) or esmolol (0.5-1 mg/kg IV) administered over 90 seconds before intubation.

ONSD/ETD measurements and hemodynamic parameters will be recorded before intubation (T0), 5 minutes after intubation (T1), and 10 minutes after intubation (T2). The primary outcome will be the change in ONSD/ETD ratio at 5 minutes after intubation. Secondary outcomes include changes in ONSD/ETD ratio at 10 minutes, mean arterial pressure, heart rate, and vasopressor requirements.

The results of this study may provide evidence regarding the optimal pharmacological strategy for attenuating intubation-related intracranial pressure changes and hemodynamic responses in patients undergoing cerebral aneurysm coil embolization.

Study Type

Interventional

Enrollment (Estimated)

84

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Turkey (Türkiye)
    • Istanbul
      • Istanbul, Istanbul, Turkey (Türkiye), 34752
        • Fatih Sultan Mehmet Training and Research Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Age ≥18 years
  • American Society of Anesthesiologists (ASA) physical status I-III
  • Scheduled for elective cerebral aneurysm coil embolization under general anesthesia
  • Planned endotracheal intubation
  • Ability to provide written informed consent

Exclusion Criteria:

  • Emergency procedures
  • Hemodynamic instability before induction of anesthesia
  • Severe cardiac conduction abnormalities or clinically significant arrhythmias
  • Contraindication or allergy to remifentanil or esmolol
  • Chronic opioid use or opioid dependence
  • Known orbital disease, ocular trauma, or conditions interfering with optic nerve sheath diameter measurements
  • Anticipated difficult airway
  • Pregnancy
  • Refusal to participate in the study

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: remifentanil group
Participants will receive remifentanil 0.5-1 µg/kg intravenously over 90 seconds before endotracheal intubation during induction of general anesthesia for elective cerebral aneurysm coil embolization.
Drug: Remifentanil
Remifentanil 0.5-1 µg/kg IV administered over 90 seconds before endotracheal intubation.
Active Comparator: Esmolol Group
Participants will receive esmolol 0.5-1 mg/kg intravenously over 90 seconds before endotracheal intubation during induction of general anesthesia for elective cerebral aneurysm coil embolization.
Drug: Esmolol
Esmolol 0.5-1 mg/kg IV administered over 90 seconds before endotracheal intubation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in ONSD/ETD Ratio at 5 Minutes After Endotracheal Intubation
Time Frame: 5 minutes after endotracheal intubation
Difference between baseline (pre-intubation) and 5-minute post-intubation optic nerve sheath diameter-to-eyeball transverse diameter ratio (ONSD/ETD).
5 minutes after endotracheal intubation

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in ONSD/ETD Ratio at 10 Minutes After Endotracheal Intubation
Time Frame: 10 minutes after endotracheal intubation
Difference between baseline (pre-intubation) and 10-minute post-intubation optic nerve sheath diameter-to-eyeball transverse diameter ratio (ONSD/ETD).
10 minutes after endotracheal intubation
Change in Mean Arterial Pressure
Time Frame: Baseline, 5 minutes, and 10 minutes after intubation
Changes in mean arterial pressure measured before intubation, 5 minutes after intubation, and 10 minutes after intubation.
Baseline, 5 minutes, and 10 minutes after intubation
Change in Heart Rate
Time Frame: Baseline, 5 minutes, and 10 minutes after intubation
Changes in heart rate measured before intubation, 5 minutes after intubation, and 10 minutes after intubation.
Baseline, 5 minutes, and 10 minutes after intubation
Vasopressor Requirement
Time Frame: From intubation until 10 minutes after intubation
Requirement for vasopressor administration during the study period following endotracheal intubation.
From intubation until 10 minutes after intubation

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Fatih Sultan Mehmet Training and Research Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

June 22, 2026

Primary Completion (Estimated)

June 1, 2027

Study Completion (Estimated)

July 1, 2027

Study Registration Dates

First Submitted

June 16, 2026

First Submitted That Met QC Criteria

June 16, 2026

First Posted (Actual)

June 22, 2026

Study Record Updates

Last Update Posted (Actual)

June 22, 2026

Last Update Submitted That Met QC Criteria

June 16, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • ONSD/ETD

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

There is no plan to make individual participant data (IPD) publicly available.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Cerebral Aneurysm Unruptured

Clinical Trials on Remifentanil

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in El Salvador

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe