Dexmedetomidine Versus Lidocaine for Optic Nerve Sheath Diameter During Craniotomy Intubation

NCT07820540 | Not Yet Recruiting Phase 4

• 1 other identifier: MD.3.6.2026
• Study Type: interventional
• Target: 90
• Locations: 1 country
• Sites: 1

Brief Summary

Endotracheal intubation during general anesthesia can cause temporary increases in heart rate, blood pressure, and intracranial pressure. These changes may be particularly important in patients undergoing craniotomy. Optic nerve sheath diameter, measured noninvasively using ultrasound, can be used as an indirect marker of changes in intracranial pressure. This randomized controlled trial will compare intravenous dexmedetomidine, intravenous lidocaine, and normal saline in patients undergoing elective supratentorial craniotomy under general anesthesia. The study will evaluate whether dexmedetomidine or lidocaine can reduce changes in optic nerve sheath diameter associated with endotracheal intubation and improve hemodynamic stability compared with placebo. The investigators hypothesize that dexmedetomidine and lidocaine will attenuate the increase in optic nerve sheath diameter and the hemodynamic response associated with endotracheal intubation.

Conditions

Endotracheal Intubation

Keywords

Optic nerve sheath diameter; Intracranial pressure; Endotracheal intubation; Craniotomy; Dexmedetomidine; Lidocaine; Hemodynamic response; Neuroanesthesia; Ultrasonography; Supratentorial craniotomy

Outcome Measures

Primary Outcomes (1)

• Optic Nerve Sheath Diameter

  Optic nerve sheath diameter will be measured in millimeters using ultrasonography with a high-frequency linear probe placed gently over the closed upper eyelid. The measurement will be obtained 3 millimeters posterior to the globe.

  Perioperative: baseline before induction; immediately after induction before laryngoscopy; immediately after intubation; 5 and 10 minutes after intubation.

Secondary Outcomes (5)

• Heart Rate

  Perioperative: baseline before induction; immediately after induction before laryngoscopy; and 1, 5, and 10 minutes after intubation.

• Mean Arterial Pressure

  Perioperative: baseline before induction of general anesthesia; immediately after completion of induction and before laryngoscopy; and 1, 5, and 10 minutes after endotracheal intubation.

• Systolic Blood Pressure

  Perioperative: baseline before induction; immediately after induction before laryngoscopy; and 1, 5, and 10 minutes after intubation.

• Diastolic Blood Pressure

  Perioperative: baseline before induction; immediately after induction before laryngoscopy; and 1, 5, and 10 minutes after intubation.

• Incidence of Intraoperative Hemodynamic Adverse Events

  Intraoperatively

Study Arms (3)

Dexmedetomidine Group

EXPERIMENTAL

Participants will receive dexmedetomidine 1 microgram per kilogram intravenously, diluted in 100 milliliters of normal saline and administered over 10 minutes before induction of anesthesia.

Drug: Dexmedetomidine

Lidocaine Group

ACTIVE COMPARATOR

Participants will receive lidocaine 1.5 milligrams per kilogram intravenously as a slow bolus 2-3 minutes before induction of anesthesia.

Drug: Lidocaine

Control Group

PLACEBO COMPARATOR

Participants will receive normal saline placebo intravenously before induction of anesthesia, administered in a manner intended to maintain study blinding.

Drug: Normal Saline

Interventions

Dexmedetomidine DRUG

Dexmedetomidine will be administered intravenously at a dose of 1 microgram per kilogram over 10 minutes before induction of general anesthesia.

Dexmedetomidine Group

Lidocaine DRUG

Lidocaine will be administered intravenously at a dose of 1.5 milligrams per kilogram as a slow bolus 2-3 minutes before induction of general anesthesia.

Lidocaine Group

Normal Saline DRUG

Normal saline will be administered intravenously as placebo before induction of general anesthesia in a manner intended to maintain study blinding.

Control Group

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults aged 18 to 65 years
• Male or female participants
• American Society of Anesthesiologists physical status I to III
• Scheduled for elective supratentorial craniotomy under general anesthesia

You may not qualify if:

• Raised intraocular pressure
• Pre-existing eye disease or ocular injury
• Severe cardiac or pulmonary disease
• Hepatic or renal impairment
• Coagulopathy
• Pregnancy
• Known allergy to any of the study drugs
• Difficult airway
• Emergency craniotomy

Sponsors & Collaborators

• Benha University: lead

Study Sites (1)

Benha University Hospitals

Banhā, Qalyubia Governorate, 13511, Egypt

Location

MeSH Terms

Interventions

Dexmedetomidine; Lidocaine; Saline Solution

Intervention Hierarchy (Ancestors)

Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Acetanilides; Anilides; Amides; Organic Chemicals; Aniline Compounds; Amines; Crystalloid Solutions; Isotonic Solutions; Solutions; Pharmaceutical Preparations

Central Study Contacts

Ahmed S Thabet, MSc

CONTACT

+965 553 09982; Drsalem2019@yahoo.com

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: Participants and the investigator responsible for data collection and outcome assessment will be blinded to group allocation. Study medications will be prepared by an independent anesthesiologist who will not participate in patient management, data collection, or outcome assessment.
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Resident of Anesthesia, Intensive Care and Pain Management

Model Details: Participants will be randomly assigned in a 1:1:1 ratio to one of three parallel groups receiving intravenous dexmedetomidine, intravenous lidocaine, or normal saline before induction of general anesthesia.

Study Record Dates

• First Submitted: September 9, 2026
• First Posted: September 15, 2026
• Study Start: September 20, 2026
• Primary Completion (Estimated): June 15, 2027
• Study Completion (Estimated): June 15, 2027
• Last Updated: September 15, 2026

Record last verified: 2026-09

Locations

EG (1)