Ropivacaine Block Alone or With Perineural or Systemic Dexamethasone for Pain in Shoulder Surgery

Phase 4

Completed

Brief Summary: Pre-operative perineural injection of dexamethasone mixed with local anesthetic in peripheral nerve blockade for orthopedic surgery has been shown to prolong the length of analgesia, improve visual analog pain scores, decrease post-operative opioid use, and decrease post-operative nausea. No study has been published to determine if this effect is a result of systemic absorption of dexamethasone or is a local effect of the drug on neuronal activity at the injection site. This study is a prospective, randomized, double-blind, controlled study to compare pain block with (1) ropivacaine and saline plus intravenous saline vs (2) ropivacaine and dexamethasone plus intravenous saline vs (3) ropivacaine and saline plus intravenous dexamethasone. Patients will be recruited sequentially and assigned to the three groups at random in equal ratios. The hypothesis is that dexamethasone injected perineurally in combination with ropivacaine for interscalene brachial plexus block will yield longer duration of sensory blockade as compared to ropivacaine alone without intravenous or perineural dexamethasone and as compared to ropivacaine and intravenous dexamethasone. This result will suggest that the effect of dexamethasone is a result of direct neuronal activity at the injection site versus systemic absorption.

Recruitment & Eligibility

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Arm && Interventions

Group	Intervention	Description
Placebo	Normal saline	Blockade with 25 ml ropivacaine 0.5% mixed with 0.8 ml normal saline, and 5 ml intravenous normal saline
Dexamethasone block	Normal saline	Blockade with 25 ml ropivacaine 0.5% mixed with 8 mg dexamethasone (0.8 ml), and 5 ml intravenous normal saline
Dexamethasone IV	Normal saline	Blockade with 25 ml ropivacaine 0.5% mixed with 0.8 ml normal saline, and intravenous 8 mg dexamethasone (0.8 ml dexamethasone, 4.2 ml saline) to total volume of 5 ml
Dexamethasone block	Ropivacaine	Blockade with 25 ml ropivacaine 0.5% mixed with 8 mg dexamethasone (0.8 ml), and 5 ml intravenous normal saline
Placebo	Ropivacaine	Blockade with 25 ml ropivacaine 0.5% mixed with 0.8 ml normal saline, and 5 ml intravenous normal saline
Dexamethasone block	Dexamethasone	Blockade with 25 ml ropivacaine 0.5% mixed with 8 mg dexamethasone (0.8 ml), and 5 ml intravenous normal saline
Dexamethasone IV	Ropivacaine	Blockade with 25 ml ropivacaine 0.5% mixed with 0.8 ml normal saline, and intravenous 8 mg dexamethasone (0.8 ml dexamethasone, 4.2 ml saline) to total volume of 5 ml
Dexamethasone IV	Dexamethasone	Blockade with 25 ml ropivacaine 0.5% mixed with 0.8 ml normal saline, and intravenous 8 mg dexamethasone (0.8 ml dexamethasone, 4.2 ml saline) to total volume of 5 ml

Primary Outcome Measures

Name	Time	Method
Duration of Sensory Blockade	Within 48 hours	Duration from time of block until complete resolution of sensory blockade in the shoulder is recorded in minutes by patient report.

Secondary Outcome Measures

Name	Time	Method
Post Operative Opioid Dose at 24 Hours	approximately 24 hours after surgery
Patient Satisfaction With Pain Control	24 hours, 48 hours, 1 week	Pain was rated on a visual analogue scale with 0 = no pain, 3=mild pain, 5=moderate pain, 7=moderate to severe pain, and 10=severe pain.
Time Until First Dose of Analgesic	Approximately 10 hours after surgery