Dose Response Study of Dexamethasone in Combination With Bupivacaine 0.25%

Study Overview
=================
Brief Summary
-----------------
When used in conjunction with a local anesthetic, dexamethasone may prolong both the sensory and motor effects of high supraclavicular brachial plexus nerve block (SBP) in arthroscopic shoulder surgery. This study seeks to determine if there is a relationship between the duration of sensory and motor blockade in supraclavicular brachial plexus nerve blocks (SBP) when combined with increasing doses of dexamethasone.

Detailed Description
-----------------
The exact mechanism of dexamethasone on peripheral nerve block is unclear. The current theory is that the effect is not dose related, while only 4mg and 8mg doses were studied. Our hypothesis is that the dose differences at 1mg, 2mg, or 4mg, does not have significant effect on the duration of analgesia. Therefore, we are not considering any patients to receive suboptimal dosing of preservative free dexamethasone in this study.

Official Title
-----------------
Dose Response Study of Dexamethasone in Combination With Bupivacaine 0.25% in Ultrasound Guided Supraclavicular Brachial Plexus Nerve Block, a Randomized, Placebo Controlled Prospective Clinical Trial

Conditions
-----------------
Post Surgical Pain

Intervention / Treatment
-----------------
* Drug: Bupivacaine 0.25%
* Drug: Dexamethasone
* Drug: normal saline


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients aged 18 to 70 scheduled for primary shoulder arthroscopy who have already elected to receive and are eligible for regional anesthesia (brachial plexus nerve block) prior to consenting for study. Ability to sign informed consent. Ability to follow study protocol, and speak, read and write in English. Must have valid phone number for follow-up purpose. Must be able to receive all protocol medications to include the dexamethasone, ketorolac, hydromorphone, and percocet. Exclusion Criteria: Patient younger than 18 years old and older than age 70 Patient refusal to sign consent Chronic opioid use (defined as narcotic use longer than 3 months) as documented in patient's medical record Allergy to any of the protocol medications Patients with severe lung disease, contra lateral phrenic nerve injury, insulin-dependent diabetes, hepatic disease/failure, kidney disease/failure as documented in patient's medical record Pregnancy (positive urine pregnancy test result in Preop area on morning of surgery)

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Bupivacaine 0.25% mixed with 1ml normal saline<br>Bupivacaine 0.25% mixed with 1ml normal saline (placebo/control group) | Drug: Bupivacaine 0.25%<br> <br> Drug: normal saline<br>* placebo<br>|
| Active Comparator: Bupivacaine 0.25% with 1mg dexamethasone (1ml)<br>Bupivacaine 0.25% mixed with 1mg preservative free dexamethasone (1ml) | Drug: Bupivacaine 0.25%<br> <br> Drug: Dexamethasone<br> <br> |
| Active Comparator: Bupivacaine 0.25% mixed with 2mg dexamethasone<br>Bupivacaine 0.25% mixed with 2mg preservative free dexamethasone (1ml) | Drug: Bupivacaine 0.25%<br> <br> Drug: Dexamethasone<br> <br> |
| Active Comparator: Bupivacaine 0.25% mixed with 4mg dexamethasone (1ml<br>Bupivacaine 0.25% mixed with 4mg preservative free dexamethasone (1ml | Drug: Bupivacaine 0.25%<br> <br> Drug: Dexamethasone<br> <br> |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Primary Outcome Variable is Post Operative Sensory Block Duration | This is defined as time from the completion of the block to the initiation of supplemental analgesia medications after hospital discharge. The patients were evaluated on different days to capture the exact end time, which was the initiation of supplemental analgesia medication. We intentionally contacted patients several times to capture the time as early as possible to minimize recall bias. | days 1, 2, and day 7 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Secondary Outcome Variable is Post Operative Motor Block Duration | This is defined as time from the completion of the block to the time when patient is able to move his or her forearm and/or hands. The patients were evaluated on different days to capture the exact end time, which was the initiation of supplemental analgesia medication. We intentionally contacted patients several times to capture the time as early as possible to minimize recall bias. | days 1, 2, and day 7 |