Dexmedetomidine in Attenuation of Haemodynamic Response to Laryngoscopy in Controlled Hypertensive Patients

Role of Intravenous Dexmedetomidine in Attenuation of Hemodynamic Response to Laryngoscopy in Controlled Hypertensive Patients: A Prospective Randomised Double-Blind Study

This randomized control trial, which was carried out at Sindh Institute of Urology and Transplantation (SIUT), used a non-probability consecutive sampling technique for six months from January 1, 2025, to June 30, 2025.

Study Overview

• Status: Completed
• Conditions: Hypertension; Anesthesia; Hemodynamic Response
• Intervention / Treatment: Other: Normal Saline; Drug: Dexmedetomidine

Detailed Description

A prospective, randomized, blinded, placebo-controlled clinical trial was conducted in the Sindh Institute of Urology and Transplantation (SIUT) Department of Anesthesiology. Before their involvement in the study, all individuals provided written informed consent.

In order to account for potential dropouts, 35 participants were recruited in each group (the dexmedetomidine group and the control group), for a total of 70 participants.

The method of non-probability consecutive sampling was utilized to select the eligible participants until the necessary sample size was obtained.

Randomization was done using computer-generated sequences, while allocation concealment was done using opaque, sealed envelopes. The sample was split into a 1:1 control group and a dexmedetomidine group at random.

Dexmedetomidine: 0.5 μg/kg of dexmedetomidine was prepared in 20 mL of 0.9% saline to infuse in the dexmedetomidine group.

Placebo: 20 mL of 0.9% saline was used to infuse in the control group.

The study infusion was assigned and administered within ten minutes of the anesthetic induction, following baseline monitoring and intravenous cannulation. Non-invasive blood pressure, pulse oximetry, three-lead ECG, end-tidal CO₂ (EtCO₂), and capnography were all part of routine monitoring. Anesthesia was induced with lignocaine. After three minutes of mask ventilation, the experienced anesthesiologists carried out direct laryngoscopy and tracheal intubation, and the laryngoscopy time was measured. Anesthesia was supported by isoflurane in a mixture of air and oxygen, and mechanical ventilation was supported to keep EtCO₂ at 35 to 40 mmHg. Bradycardia (less than 50 beats per minute) was corrected using atropine 0.5 mg intravenously, and hypotension was corrected with ephedrine 5 mg intravenously.

• Study Type: Interventional
• Enrollment (Actual): 70
• Phase: Phase 3

Contacts and Locations

Study Locations

• Pakistan
  • Sindh
    • Karachi, Sindh, Pakistan, 74200
      • Sindh Institute of urology and Transplantation

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Ages from 18 to 65 years.
• Patients with a known case of controlled hypertension.
• ASA II
• Elective surgical procedure under general anaesthesia.
• Mallampati grades 1 and 2.
• Patients consenting to participate in this study

Exclusion Criteria:

• Patients with an anticipated difficult intubation.
• Those requiring more than 15 seconds or more than one attempt or use of a bougie during laryngoscopy.
• A patient who has not taken an antihypertensive drug early morning on the day of surgery.
• Patients with a history of allergy to drugs being used.
• Patients with uncontrolled hypertension (BP > 140/90 mmHg).
• History of bradycardia (resting heart rate < 60 bpm).
• Patients on beta blockers if resting heart rate < 60 bpm.
• History of valvular heart disease, uncontrolled diabetes, liver, or kidney disease.
• Pregnancy.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Normal saline; The control group (Group A) was treated with normal saline 0.9%, constituted as a 20 mL solution in a 25 mL syringe. An independent anaesthesiologist who was not involved in administering general anaesthesia or recording the study parameters prepared the study drug. It was then handed over to the primary anaesthesiologist for administration. The study drugs were administered intravenously using a syringe pump over 10 min.	Other: Normal Saline; 20 mLs of normal saline was administered intravenously using a syringe pump over 10 min.; Other Names: dexmedetomidine
Experimental: Dexmedetomidine; (Group B) dexmedetomidine 0.5mcg/kg was constituted as a 20 mL solution in a 25 mL syringe. An independent anaesthesiologist who was not involved in administering general anaesthesia or recording the study parameters prepared the study drug. It was then handed over to the primary anaesthesiologist for administration. The study drugs were administered intravenously using a syringe pump over 10 min.	Drug: Dexmedetomidine; Dexmedetomidine (0.5 mcg/kg) diluted in 20 mLs of normal saline was administered intravenously using a syringe pump over 10 min.; Other Names: Normal saline

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart Rate via 3 lead ECG monitor	In the operating room, the ASA standard monitoring was attached to the patient.	Perioperative
Systolic Blood Pressure measured via a non invasive blood pressure device	In the operating room holding area, the ASA standard monitoring was attached to the patient, which includes a non-invasive blood pressure monitor (cuff size was used according to the patient's weight and height).	Perioperative
Diastolic Blood Pressure measured via a non invasive blood pressure device	In the operating room, the ASA standard monitoring was attached to the patient, which includes a non-invasive blood pressure monitor (cuff size was used according to the patient's weight and height).	Perioperative
Mean Blood Pressure measured via a non-invasive blood pressure device	In the operating room, the ASA standard monitoring was attached to the patient, which includes a non-invasive blood pressure monitor (cuff size was used according to the patient's weight and height).	Perioperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Bradycardia (heart rate less than 60 beats per minute)	Measured by an ECG monitor	Perioperative
Hypotension	Systolic blood pressure less than 90 mmHg measured via a non-invasive blood pressure device	Perioperative

Collaborators and Investigators

• Sponsor: Sindh Institute of Urology and Transplantation
• Investigators: Principal Investigator: Syed M Abbas, Sindh Institute of urology and Transplantation

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2025
• Primary Completion (Actual): June 30, 2025
• Study Completion (Actual): June 30, 2025

Study Registration Dates

• First Submitted: January 5, 2026
• First Submitted That Met QC Criteria: April 25, 2026
• First Posted (Actual): April 29, 2026

Study Record Updates

• Last Update Posted (Actual): April 29, 2026
• Last Update Submitted That Met QC Criteria: April 25, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Hypertension; Dexmedetomidine; Stress response; Direct Laryngoscopy
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Wounds and Injuries; Fractures, Bone; Hypertension; Fractures, Stress; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Pharmaceutical Preparations; Azoles; Imidazoles; Crystalloid Solutions; Isotonic Solutions; Solutions; Dexmedetomidine; Saline Solution
• Other Study ID Numbers: SIUT-ERC-2024/A-488

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Full anonymous raw data, results and statistical analysis

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No