Intravenous Dexamethasone on Supraclavicular Brachial Plexus Block for Shoulder Arthroscopy

Study Overview
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Brief Summary
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Previous studies have confirmed that IV dexamethasone prolongs brachial plexus blocks. However, these studies only used fixed doses of IV dexamethasone at relatively high doses, which could potentially lead to increased glucose levels, delayed wound healing, and unintended side effects. There remains a paucity of research on the effective dose range of IV dexamethasone for the prolongation of supraclavicular blocks. The optimal dosage of IV dexamethasone for prolongation of analgesia vs. motor block prolongation from supraclavicular blocks in shoulder surgery has yet to be delineated.

Detailed Description
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Numerous studies have confirmed that perineural dexamethasone prolongs bupivacaine and ropivacaine brachial plexus blocks by approximately 10 hours (from approx. 12 to 22 hours) without clinical evidence of toxicity. However, perineural toxicity in an animal model has raised concern about its use as a peripheral nerve block adjuvant. Moreover, recent studies suggest that high dose IV dexamethasone (810mg) prolongs analgesia to a similar degree as perineural dexamethasone for interscalene, supraclavicular and sciatic nerve blocks performed with ropivacaine and bupivacaine. However these studies only utilized fixed, high level doses of IV dexamethasone. Moreover, there remains a concern that high dose IV dexamethasone may lead to postoperative hyperglycemia and could possibly increase the risk of postoperative wound infection. Open surgery under general anesthesia has been shown to increase blood glucose levels with a peak at approximately 2 hours post-induction and results have been conflicting regarding whether or not IV dexamethasone causes greater increase. To the investigators' knowledge, it is not yet known if arthroscopic surgery under regional anesthesia triggers a similar increase in blood glucose levels and if this is impacted by administration of IV dexamethasone. The investigators aim to identify the duration of supraclavicular block prolongation that can be expected over a range of doses of IV dexamethasone. The investigators also seek to identify what association, if any, is noted between IV dexamethasone and changes in blood glucose levels after shoulder surgery with regional anesthesia and sedation. Finally, the investigators will collect data on side effects and postoperative complications, if any, in patients receiving a range of doses of IV dexamethasone.

Official Title
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Intravenous Dexamethasone for Prolongation of Analgesia Following Supraclavicular Brachial Plexus Block for Shoulder Arthroscopy: A Randomized, Controlled, Phase IV Dose-Response Study

Conditions
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Shoulder Arthroscopy, Pain

Intervention / Treatment
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* Drug: IV Saline
* Drug: IV Dexamethasone 4mg
* Drug: IV Dexamethasone 6mg
* Drug: IV Dexamethasone 8mg


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Patients undergoing shoulder arthroscopy under regional anesthesia Exclusion Criteria: General anesthesia Contraindication to regional anesthesia Pre-existing neuropathy in the surgical limb Diabetes Mellitus History of postoperative nausea and vomiting &/ or motion sickness Procedures involving biceps tenotomy Peri-articular cocktail injections given intraoperatively to augment pain relief Chronic pain (daily opioid and/or gabapentinoid use for 6 weeks) Open surgical procedures Corticosteroid injection within 1 month Patients on systemic oral or IV steroid therapy within 6 months

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: 0mg IV Dexamethasone<br>0mg IV Dexamethasone | Drug: IV Saline<br> <br> |
| Experimental: 4mg IV Dexamethasone<br>4mg IV Dexamethasone | Drug: IV Dexamethasone 4mg<br> <br> |
| Experimental: 6mg IV Dexamethasone<br>6mg IV Dexamethasone | Drug: IV Dexamethasone 6mg<br> <br> |
| Experimental: 8mg IV Dexamethasone<br>8mg IV Dexamethasone | Drug: IV Dexamethasone 8mg<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of Analgesia From a Supraclavicular Block Performed for Shoulder Arthroscopy | Defined as time from block placement until pain relief from the block completely wears off in the operative shoulder. | Day of Surgery until Post-Operative Day 3 (if the block persists) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of Motor Block From the Supraclavicular Block | Defined as the time from block placement to restoration of normal strength at both the wrist and elbow. | Day of Surgery until Post-Operative Day 3 (if the block persists) | 
| Blood Glucose Levels | Fingerstick blood glucose test to be administered before and 1-hour and 2-hours after IV dexamethasone administration. | Day of Surgery - before and 1-hour and 2-hours after IV Dexamethasone administration | 
| Occurrence of Postoperative Neuropraxia | Documentation of any of these occurrences will be obtained from the surgeons and/or medical charts after the postoperative follow up visit. | Post-Operative Day 21 | 
| Occurrence of Postoperative Wound Infection | Documentation of any of these occurrences will be obtained from the surgeons and/or medical charts after the postoperative follow up visit. | Post-Operative Day 21 | 
| Average Daily Pain Scores at Rest and With Movement | Using the Numeric Rating Scale (NRS) Pain obtained by patient interview. Lower numbers represent less pain and better outcomes. The scale range is from 0 (no pain) to 10 (worst pain possible). | Day of Surgery until Post-Operative Day 3 (if the block persists) | 
| Worst Daily Pain Scores at Rest and With Movement | Using the numeric pain rating scale (NRS), will be obtained by patient interview. Lower numbers represent less pain and better outcomes. The scale range is from 0 (no pain) to 10 (worst pain possible). | Day of Surgery until Post-Operative Day 3 (if the block persists) | 
| Patient Satisfaction With Postoperative Analgesia | Patient satisfaction with postoperative analgesia will be obtained by patient interview. Lower numbers represent worse outcomes. The scale range is from 0 (worst) to 10 (best). | Post-Operative Day 2 or Post-Operative Day 3 (if the block persists) | 
| Cumulative Daily Opioid Usage | Dosages (reported in Morphine equivalent units) of opioid medication obtained by medical records and/or by patient interview. | Recovery Room until Post-Operative Day 3 (if block persists) |