Comparison Between Intrathecal Magnesium Sulphate & Dexmedetomidine in DHS

Comparative Evaluation of Intrathecal Dexmedetomidine and Magnesium Sulphate as Adjuvants to 0.5% Hyperbaric Bupivacaine for Spinal Anesthesia in Patients Undergoing Dynamic Hip Screw (DHS) Fixation: A Randomized Clinical Study

To compare the efficacy and safety of intrathecal dexmedetomidine and magnesium sulphate as adjuvants to 0.5% hyperbaric bupivacaine in patients undergoing elective DHS fixation, focusing on onset and duration of sensory and motor block, hemodynamic stability, and quality of postoperative analgesia.

Study Overview

• Status: Not yet recruiting
• Conditions: Effects of Dexmedetomidine & Magnesium Sulphate on Patients Undergoing DHS
• Intervention / Treatment: Drug: Dexmedetomidine; Drug: Magnesium Sulphate

Detailed Description

Spinal anesthesia is a preferred technique for lower limb orthopedic surgeries due to its rapid onset, reliable sensory and motor blockade, and minimal systemic side effects. Hyperbaric bupivacaine 0.5% is commonly used; however, its duration may be insufficient for prolonged procedures or postoperative analgesia. To enhance and prolong anesthesia and analgesia, various intrathecal adjuvants have been investigated.

Dexmedetomidine, a selective α2-adrenergic agonist, has shown promise in improving the quality and duration of spinal anesthesia by providing prolonged sensory and motor blockade, stable hemodynamics, and enhanced postoperative analgesia. Similarly, magnesium sulphate, an NMDA receptor antagonist, exerts antinociceptive effects by modulating calcium influx in nerve cells, potentially prolonging analgesia without significant motor blockade.

Dynamic hip screw (DHS) fixation is a common surgical intervention for intertrochanteric femur fractures, particularly in elderly patients. These procedures demand reliable intraoperative anesthesia and effective postoperative pain control to facilitate early mobilization and reduce complications.

Despite individual studies evaluating these agents, direct comparisons between intrathecal dexmedetomidine and magnesium sulphate as adjuvants to bupivacaine in DHS fixation remain limited. This study aims to compare their efficacy and safety in enhancing spinal anesthesia, thereby optimizing perioperative care in patients undergoing elective DHS fixation.

• Study Type: Interventional
• Enrollment (Estimated): 92
• Phase: Phase 3

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age: 18-65 year
• ASA Physical Status I or II
• Scheduled for elective DHS fixation under spinal anesthesia
• Written informed consent provided
• Patients of both sex are included in the study.

Exclusion Criteria:

• Patient refusal
• Allergy to study drugs
• Local infection at injection site
• Neurological or psychiatric illness
• Coagulopathy
• Chronic opioid or sedative use

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Group D (Dexmedetomidine)	Drug: Dexmedetomidine; 2.5 mL 0.5% hyperbaric bupivacaine + 5 µg dexmedetomidine (0.5 mL), total volume 3 mL
Active Comparator: Group M (Magnesium Sulphate)	Drug: Magnesium Sulphate; 2.5 mL 0.5% hyperbaric bupivacaine + 50 mg magnesium sulphate (0.5 mL), total volume 3 mL

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Highest Dermatome Level of Sensory Block	Sensory block level assessed using a pinprick test and recorded as the highest dermatome level with loss of sensation.	24 hours after intervention
Duration of postoperative analgesia	The outcome is Measured by Vas Score to assess pain intensity. It consists of a numeric version of the visual analogue scale. It is a horizontal line with an eleven point numeric range. It is labeled from zero to ten, with zero being an example of someone with no pain and ten being the worst pain possible. This scale can be administered verbally. Vas score for 24 h will be assessed at 0., 1, 12 and 24 h postoperatively and will be recorded.	24 hours after intervention
Degree of Motor Block	Motor block assessed using the Modified Bromage Scale (0-3), where higher scores indicate greater motor block.	24 hours after intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart Rate	Heart rate measured in beats per minute (bpm)	24 hours after intervention
Incidence of Adverse Effects	Bradycardia Hypotension Nausea Vomiting Sedation (Assessed By Ramsay Sedation Scale (RSS) ) Shivering Respiratory depression Delayed motor block Flushing Warm sensation Headache Pruritus Urinary retention Neurological complications (e.g., transient paresthesia)	24 hours after Intervention
Mean Arterial Pressure	Mean arterial pressure measured in mmHg	24 hours after intervention
Oxygen Saturation	Peripheral oxygen saturation measured by pulse oximetry by percentage	24 hours after intervention

Collaborators and Investigators

• Sponsor: Assiut University

Study record dates

Study Major Dates

• Study Start (Estimated): February 1, 2026
• Primary Completion (Estimated): November 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: November 19, 2025
• First Submitted That Met QC Criteria: December 24, 2025
• First Posted (Actual): January 8, 2026

Study Record Updates

• Last Update Posted (Actual): January 8, 2026
• Last Update Submitted That Met QC Criteria: December 24, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Sulfur Compounds; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Azoles; Imidazoles; Inorganic Chemicals; Sulfur Acids; Sulfates; Sulfuric Acids; Magnesium Compounds; Dexmedetomidine; Magnesium Sulfate
• Other Study ID Numbers: Intrathecal Mgso4& Dex. In DHS

Drug and device information, study documents

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