Intravenous Dexmedetomidine Versus Midazolam in Preventing Shivering in Trauma Patients Undergoing Lower Limb Orthopedic Surgery Under Spinal Anesthesia

Shivering is a common and significant complication following spinal anesthesia, with a reported incidence of 40-60% especially in trauma patients due to pain, stress response, blood loss, and disrupted thermoregulation. Shivering increases oxygen demand, impairs monitoring, and reduces patient comfort. Effective pharmacologic prevention of shivering is crucial in this population.

Dexmedetomidine is a highly selective α2-adrenoreceptor agonist. It is widely used as an adjunct to general as well as regional anesthesia for better hemodynamic stability, sedation, and prolonged duration of regional anesthesia and is effective in reducing shivering by centrally modulating thermoregulation.

Midazolam, a GABA-A agonist, Intravenous midazolam premedication is commonly used for conscious sedation, anxiolysis, and amnesia with spinal anesthesia is also known to have anti-shivering properties attributed to its action on GABA-A receptors, promoting anxiolysis and possibly resetting the hypothalamic thermoregulatory threshold.

There are limited clinical data comparing the effect of intravenous dexmedetomidine and midazolam and its effect on shivering

Study Overview

• Status: Not yet recruiting
• Conditions: Lower Limb Orthopedic Surgery
• Intervention / Treatment: Drug: Dexmedetomidine; Drug: Midazolam

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Phase 4

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• : ASA I-II Adult trauma patients (age 18-60 years). Undergoing lower limb orthopedic surgery with tourniquet under spinal anesthesia

Exclusion Criteria:

- Allergy to study drugs. Severe cardiovascular, hepatic, or renal disease Hypovolemic shock. History of psychiatric illness or chronic sedative use. Bradycardia (<50 bpm), heart block, or uncontrolled hypotension. Febrile illness or use of active warming devices

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group D; Patients will receive i. v. dexmedetomidine 0.5 μg.kg-1 post-spinal anesthesia	Drug: Dexmedetomidine; Patients will receive i. v. dexmedetomidine 0.5 μg.kg-1 post-spinal anesthesia
Experimental: Group M; and patients will receive i.v. midazolam 0.05 mg.kg-1 post-spinal anesthesia	Drug: Midazolam; patients will receive i.v. midazolam 0.05 mg.kg-1 post-spinal anesthesia

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of shivering	Incidence of shivering intraoperatively every 10 min and postoperatively every 15 min for 1 hour	1 hours postoperative

Collaborators and Investigators

• Sponsor: Assiut University

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): April 1, 2027

Study Registration Dates

• First Submitted: December 20, 2025
• First Submitted That Met QC Criteria: December 20, 2025
• First Posted (Actual): December 24, 2025

Study Record Updates

• Last Update Posted (Actual): December 24, 2025
• Last Update Submitted That Met QC Criteria: December 20, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Azoles; Imidazoles; Benzazepines; Benzodiazepines; Midazolam; Dexmedetomidine
• Other Study ID Numbers: Dexmedetomidine VS Midazolam

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes