Magnesium Sulphate in the Ultrasound-guided Supraclavicular Brachial Plexus Block

Study Overview
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Brief Summary
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This study evaluated the motor and sensory block duration and the postoperative analgesic effects of adding Magnesium Sulphate to bupivacaine in the ultrasound-guided supraclavicular brachial plexus block Anesthesia. Motor and sensory block duration were considered as a primary endpoint.

Detailed Description
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The supraclavicular approach to the brachial plexus provides more consistent and effective regional anesthesia to the upper extremity than other approaches to brachial plexus blockade. However, the fear of pneumothorax is often cited by anesthetists as a reason to avoid this approach. With increasing affirmation on patient safety and better patient outcomes, ultrasound guided regional anesthesia (UGRA) is becoming more widely popular. Ultrasound provides clinicians with a real time image suitable for visualizing anatomical structures, needle placement, and local anesthetic spread. Ultrasound-guidance to supraclavicular brachial plexus block has shown to increase success rates, reduce the volume of local anesthetic (LA) used and has the potential to minimize the risk of complications. Although there are many treatment choices for postoperative pain, a gold standard has not been established. Prolonging the duration of peripheral nerve blocks using long-acting Local Anesthesia or perineural catheters can be used. However, perineural catheters are more time-consuming, costly, has possible higher complication rates (e.g. Infection), and needs more postoperative care. Several adjuvants such as fentanyl, alpha-2 adrenergic agonists (clonidine or dexmedetomidine), tramadol, and magnesium have been used to extend the duration of peripheral nerve blocks. 5-7 Magnesium has antinociceptive effects in animal and human models, principally related to blocking the N-methyl-D-aspartate (NMDA) receptors and regulation of calcium influx into cells. Calcium influx leads to a sequence of central sensitization such as windup phenomenon and long term potentiation which are crucial mechanisms that determine the duration and intensity of post-operative pain. Magnesium prevents central sensitization triggered by peripheral nociceptive stimulation in response to painful stimuli. The investigators designed this study to evaluate the effect of adding magnesium sulphate to bupivacaine in the ultrasound-guided supraclavicular brachial plexus block anesthesia. The sensory and motor block durations were evaluated as primary endpoints and the postoperative analgesic effects as a secondary endpoint.

Official Title
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The Effect on Outcome of Adding Magnesium Sulphate to Bupivacaine in the Ultrasound-guided Supraclavicular Brachial Plexus Block Anesthesia

Conditions
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Pain

Intervention / Treatment
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* Drug: Magnesium Sulphate


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - ASA physical status I to II, - Patients listed for elective forearm or hand surgery using supraclavicular brachial plexus block anesthesia Exclusion Criteria: 1 - evidence of severe cardiovascular, renal, or hepatic diseases, preexisting neurological or psychiatric illnesses. 2- patients have allergy to the study drugs. 3 - patients who have any contraindications to brachial plexus block anesthesia. 4- pregnant or lactating women, or 5- if the BMI was > 35 kg/m2.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: group Bupivacaine<br>patients will receive 23 mL of Bupivacaine HCL 0.5% (Marcaine, 5 mg per mL; Hospira, USA) in addition to 2 mL normal saline using Ultrasound-guided Supraclavicular Brachial Plexus Block | |
| Active Comparator: group Bupivacaine Magnesium<br>patients will receive 23 mL of Bupivacaine HCL 0.5% in addition to 2 mL (100 mg) Magnesium Sulphate (Magnesium Sulphate 50 %, 500 mg per mL; Hospira, USA) diluted with normal saline. using Ultrasound-guided Supraclavicular Brachial Plexus Block | Drug: Magnesium Sulphate<br>* Magnesium has antinociceptive effects in animal and human models, principally related to blocking the N-methyl-D-aspartate (NMDA) receptors and regulation of calcium influx into cells.<br>* Other names: Bupivacaine HCL 0.5%;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The sensory block duration (the time interval between the end of local anesthetic administration and restoration of normal sensation) were evaluated as primary endpoint | extended | 12 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the postoperative analgesic effects (the time interval between the end of local anesthetic administration and the first analgesia given) as a secondary endpoint. | improved | 12 hours |