The Effects of Dexamethasone on Low Dose Interscalene Brachial Plexus Block (ISB-Dex)

Comparison of the Effects of Perineural Versus Systemic Dexamethasone on Low Dose Interscalene Brachial Plexus Block: A Randomized Control Trial

A standard interscalene nerve block is performed with long acting local anesthetic (bupivacaine or ropivacaine in concentrations varying from 0.25% to 0.75%). The purpose of this study is to investigate the effect of the addition of perineural dexamethasone (4mg) to a standard ropivacaine solution (0.5%) on analgesic duration of low dose interscalene block compared to ropivacaine alone for interscalene block with systemic dexamethasone.

Ropivacaine is not an intervention as a local anesthetic is pre-requisite to performing a nerve block.

Study Overview

• Status: Completed
• Conditions: Shoulder Surgery; Nerve Block
• Intervention / Treatment: Drug: Perineural dexamethasone; Drug: Systemic Dexamethasone

Detailed Description

Interscalene brachial plexus block (ISB) is regarded as the standard of care for analgesia after shoulder surgery providing superior analgesia and reducing opioid consumption. Shoulder surgery, previously requiring inpatient admission for pain control, is now commonly performed on an ambulatory basis facilitated by ISB analgesia. The effects of single injection ISB dissipate after several hours unmasking the moderate to severe pain of the surgical insult and require strong opioid analgesia. Efforts to prolong ISB duration by increasing local anaesthetic (LA) dose are limited by their pharmacodynamics and narrow therapeutic window. To address some of these issues faced with prolonging ISB analgesia the addition of perineural adjuvants to local anesthetic (eg. clonidine, dexmedetomidine), have been investigated in an attempt to prolong peripheral nerve block duration with limited success. However, the corticosteroid dexamethasone, has been added to local anesthetic solutions for ISB and has demonstrated promise in preliminary studies. Perineural dexamethasone (8-10mg) in conjunction with local anesthetic prolongs the duration of ISB with an effect sizes ranging from 40% to 75% (absolute effect ~ 6 to 10 hours). Dexamethasone, however, is only approved for intramuscular or intravenous administration and therefore perineural use is currently off-label. There are several reasons that warrant a new randomized trial. Chiefly, all of the previous trials do not reflect modern regional anesthetic practice. These trials utilized peripheral nerve stimulation (PNS) and local anesthetic volumes of 30 to 40 ml. Modern ultrasound guided ISB (US-ISB) allows for more accurate, targeted deposition of local anesthetic with volumes ranging from 5 to 10 ml with no difference in block efficacy or duration compared to larger volumes (≥20ml). An ideal solution would be a local anesthetic with adjuvant mixture that allowed administration of lower volumes but with prolonged analgesic duration. The use of low dose local anesthetic with dexamethasone could be one such solution. A trial that demonstrates enhanced block quality and duration associated with perineural dexamethasone added to low dose local anesthetic may allow us to achieve both prolonged duration of effect and reduced side effects due to unwanted local anesthetic spread. This would create further significant benefits for patients and further promote the use of low dose local anesthetic techniques to anesthesiologists who do not currently use this technique.

• Study Type: Interventional
• Enrollment (Actual): 182
• Phase: Phase 4

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M4N 3M5
      • Sunnybrook Health Sciences Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Patients undergoing arthroscopic shoulder surgery at Sunnybrook Health Sciences Centre, Toronto Western Hospital and Women's College Hospital.
2. ASA functional status class I to III
3. Age 18 to 80 years
4. BMI ≤ 35 kg/m2

Exclusion Criteria:

1. Lack of patient consent
2. Allergy to dexamethasone or ropivacaine
3. BMI > 35 kg/m2
4. Contraindications to low dose dexamethasone including peptic ulcer disease, systemic infection, glaucoma, active varicella/herpetic infections, diabetes mellitus
5. Contraindications to ISB including severe Chronic Obstructive Pulmonary Disease (Forced expiratory volume < 40% predicted), coagulopathy, pre-existing neurologic deficit in ipsilateral upper extremity, localized infection
6. Pregnant or nursing females
7. Chronic opioid use defined as > 30mg oral morphine or equivalent per day
8. Unable to take acetaminophen or celecoxib

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: QUADRUPLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: Perineural Dexamethasone; ISB performed with local anesthetic (ropivacaine 0.5%) and perinerual dexamethasone (4mg)	Drug: Perineural dexamethasone; Perinerual administration of dexamethasone (4mg); Other Names: Dexamethasone Sodium Phosphate Injection
OTHER: Systemic Dexamethasone; ISB with local anesthetic alone (ropivacaine 0.5%) alone and intravenous dexamethasone (4mg)	Drug: Systemic Dexamethasone; Intravenous infusion of dexamethasone (4mg); Other Names: Dexamethasone Sodium Phosphate Injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Duration of Sensory Block	Defined as time from completion of block procedure to NRS for pain > 0 (in hours)	1 day postoperative

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Postoperative Nausea and/or Vomiting	Number of participants with postoperative nausea and/or vomiting assessed at 12 hours, 24, hours, and 7 days postoperatively	7 days postoperative
Time to First Opioid Consumption	Defined as time from completion of block procedure to first consumption of opioid analgesic (in hours)	1 day postoperative
Duration of Motor Block	Defined as time from completion of block procedure to return to baseline motor function (in hours)	1 day postoperative
Post-operative Oxygen Saturation on Room Air	Pulse oximetry (in %) measured 1 hour after arrival in post-operative recovery room, scale 0-100, higher number is better	1 hour postoperative
Opioid Consumption	Opioid consumption (in oral morphine equivalents) will be recorded at 12 hours, 24 hours, and 7 days	7 days postoperative
Numeric Rating Scale for Pain (NRS 0-10)	Recorded at 12 hours, 24 hours, and 7 days 0 is no pain, 10 is the worst pain imaginable. Lower number is better.	7 days postoperative
Postoperative Serum Blood Glucose	Measured 1 hour after arrival to the post-operative recovery room	1 hour postoperative
Number of Participants With Nerve Damage From Interscalene Block	Defined as persistent paresthesia, and sensory/motor block at 7 days	7 Days postoperative
Infection	Number of participants with localized infection at nerve block site	7 Days postoperative

Collaborators and Investigators

• Sponsor: Dr. Stephen Choi
• Collaborators: The Physicians' Services Incorporated Foundation
• Investigators: Principal Investigator: Stephen Choi, MD,FRCPC,MSc, SunnybrookHealth Sciences Centre

Publications and helpful links

General Publications

• McHardy PG, Singer O, Awad IT, Safa B, Henry PDG, Kiss A, Au SK, Kaustov L, Choi S. Comparison of the effects of perineural or intravenous dexamethasone on low volume interscalene brachial plexus block: a randomised equivalence trial. Br J Anaesth. 2020 Jan;124(1):84-91. doi: 10.1016/j.bja.2019.08.025. Epub 2019 Oct 5.

Study record dates

Study Major Dates

• Study Start (ACTUAL): January 1, 2015
• Primary Completion (ACTUAL): January 1, 2019
• Study Completion (ACTUAL): May 1, 2019

Study Registration Dates

• First Submitted: December 16, 2014
• First Submitted That Met QC Criteria: December 18, 2014
• First Posted (ESTIMATE): December 23, 2014

Study Record Updates

• Last Update Posted (ACTUAL): July 15, 2020
• Last Update Submitted That Met QC Criteria: July 6, 2020
• Last Verified: July 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Autonomic Agents; Peripheral Nervous System Agents; Enzyme Inhibitors; Anti-Inflammatory Agents; Antineoplastic Agents; Antiemetics; Gastrointestinal Agents; Glucocorticoids; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Antineoplastic Agents, Hormonal; Protease Inhibitors; Dexamethasone; Dexamethasone acetate; BB 1101; Dexamethasone 21-phosphate
• Other Study ID Numbers: 437-2013

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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