Intravenous Dexamethasone With Single-Shot Versus Continuous Brachial Plexus Block for Rebound Pain After Shoulder Surgery

Pain Management Protocol Optimization for Rebound Pain Prevention and Enhanced Recovery After Shoulder Surgery: A Randomized Noninferiority Trial of Intravenous Dexamethasone Combined With Single-Shot Versus Continuous Brachial Plexus Block

Shoulder surgery often causes severe pain after the operation. To control this pain, doctors commonly perform a nerve block (interscalene brachial plexus block), which numbs the shoulder area. However, when the effect of a single-injection nerve block wears off, many patients experience sudden, intense pain known as "rebound pain".

One way to prevent rebound pain is to place a thin catheter near the nerves so that local anesthetic can be given continuously for a longer period (continuous nerve block). However, this method is technically demanding and can cause problems such as catheter dislodgement, infection, and inconvenience for patients. Another simpler option is to give a single-injection nerve block together with an intravenous (IV) injection of dexamethasone, a steroid medication known to prolong the effect of nerve blocks and reduce rebound pain.

The purpose of this study is to determine whether a single-injection nerve block combined with IV dexamethasone (5 mg) is not inferior to a continuous nerve block in preventing rebound pain after shoulder surgery. A total of 92 adult patients scheduled for elective shoulder surgery will be randomly assigned to one of the two groups. The main outcome is the rebound pain score, defined as the difference between the last pain score recorded in the recovery room (while the nerve block is still working) and the highest pain score reported within the first 24 hours after the nerve block. The investigators expect that the simpler single-injection method with IV dexamethasone will provide comparable pain control while avoiding the complications and inconvenience of catheter-based continuous nerve blocks.

Study Overview

• Status: Not yet recruiting
• Conditions: Pain, Postoperative; Rotator Cuff Injuries; Shoulder Injuries; Rebound Pain
• Intervention / Treatment: Drug: Dexamethasone (IV); Procedure: Single-shot interscalene brachial plexus block; Procedure: Continuous interscalene brachial plexus block

• Study Type: Interventional
• Enrollment (Estimated): 92
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Hansol Kim, M.D.; Phone Number: +82-2-2072-2467; Email: hansolfrkr@gmail.com
• Study Contact Backup: Name: Hwan Suk Jang, M.D.; Phone Number: +82-2-2072-2467; Email: j4n6h5@gmail.com

Study Locations

• South Korea
  • Jongno-gu
    • Seoul, Jongno-gu, South Korea, 03080
      • Seoul National University Hospital
      • Contact: Hansol Kim, M.D.; Phone Number: +82-2-2072-2467; Email: hansolfrkr@gmail.com
      • Contact: Hwan Suk Jang, M.D.; Phone Number: +82-2-2072-2467; Email: j4n6h5@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients aged 19 to 79 years scheduled for elective shoulder surgery under brachial plexus block and monitored anesthesia care (MAC)

Exclusion Criteria:

• Pre-existing neurological deficit of the brachial plexus
• Emergency surgery
• American Society of Anesthesiologists (ASA) physical status classification IV or higher
• Contraindication or history of hypersensitivity to local anesthetics or dexamethasone
• Severe pulmonary disease (e.g., chronic obstructive pulmonary disease)
• Body mass index (BMI) ≥ 35 kg/m²
• Long-term use of steroids
• Long-term use of analgesics
• Inability to cooperate or communicate
• Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Single-shot block with IV dexamethasone; Participants receive a single-shot ultrasound-guided interscalene brachial plexus block with 0.75% ropivacaine 15-20 mL, followed by intravenous dexamethasone 5 mg administered after confirmation of successful block on arrival in the operating room. Postoperatively, an intravenous patient-controlled analgesia (PCA) pump with fentanyl (10 mcg/mL, bolus 1 mL, lockout 6 min, no basal rate) is connected. All participants receive standard multimodal analgesia (intravenous acetaminophen 1000 mg plus ibuprofen 300 mg every 8 hours).	Drug: Dexamethasone (IV); Intravenous dexamethasone 5 mg, administered as a single dose after confirmation of adequate sensory and motor block on arrival in the operating room.; Procedure: Single-shot interscalene brachial plexus block; Ultrasound-guided single-shot interscalene brachial plexus block performed with a 50 mm needle. 0.75% ropivacaine 15-20 mL is injected at the interscalene level. No perineural catheter is placed.
Active Comparator: Continuous interscalene brachial plexus block; Participants receive an ultrasound-guided continuous interscalene brachial plexus block: 0.75% ropivacaine 15-20 mL is injected at the interscalene level, and a perineural catheter is placed with the tip adjacent to the superior trunk. Postoperatively, a nerve block PCA (0.2% ropivacaine, basal rate 5 mL/h, bolus 3 mL, lockout 30 min) is connected via the catheter. All participants receive the same standard multimodal analgesia as the experimental arm.	Procedure: Continuous interscalene brachial plexus block; Ultrasound-guided interscalene brachial plexus block with 0.75% ropivacaine 15-20 mL, followed by placement of a perineural catheter adjacent to the superior trunk. Continuous postoperative analgesia is provided through the catheter using 0.2% ropivacaine (basal rate 5 mL/h, bolus 3 mL, lockout time 30 min) via a patient-controlled analgesia pump.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rebound Pain Score (RPS)	Difference between the last pain score recorded in the post-anesthesia care unit (PACU) while the nerve block is still effective and the highest pain score reported within the first 24 hours after the nerve block, measured on an 11-point Numerical Rating Scale (NRS; 0 = no pain, 10 = worst pain imaginable). Higher scores indicate more severe rebound pain. Non-inferiority margin: 1.5.	Within 24 hours after the nerve block

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative pain score (NRS)	Pain intensity at rest and during movement, measured on an 11-point NRS (0 = no pain, 10 = worst pain imaginable).	4, 8, 12, 24, and 48 hours after surgery
Peak NRS pain score	Highest pain score reported during each period, on an 11-point NRS.	0-24 hours and 24-48 hours after surgery
Incidence of severe rebound pain	Proportion of participants experiencing rebound pain with NRS ≥ 7.	Within 24 hours after the nerve block
Block duration	Time from completion of the nerve block to the first onset of pain.	Up to 48 hours after the nerve block
Time to first rescue analgesic	Time from the end of surgery to the first administration of rescue analgesics.	Up to 48 hours after surgery
Cumulative opioid consumption	Cumulative opioid consumption converted to oral morphine equivalents (OME), including PCA use and rescue opioids.	24 and 48 hours after surgery
Block performance time	Single-shot group: time from donning gloves to needle removal. Continuous group: time from donning gloves to completion of aseptic dressing.	During the block procedure (day of surgery)
Block failure rate	Proportion of participants with inadequate sensory/motor block on arrival in the operating room requiring rescue block.	From block completion to start of surgery (day of surgery)
Rescue block administration	Proportion of participants requiring an additional rescue block (0.75% ropivacaine 5-10 mL).	Day of surgery
Intraoperative rescue analgesic use	Proportion of participants requiring intraoperative rescue analgesics (IV fentanyl 50-100 μg).	During surgery
Conversion to general anesthesia	Proportion of participants requiring conversion to general anesthesia due to inadequate block or uncontrolled pain.	During surgery
Intraoperative sedative consumption	Total dose of propofol administered for sedation during surgery.	During surgery
Quality of Recovery-15 Korean version (QoR-15K) score	Quality of recovery assessed using the QoR-15K questionnaire (score range 0-150; higher scores indicate better recovery).	Baseline (day before surgery) and 24 hours after surgery
Incidence of postoperative nausea and vomiting (PONV)	Proportion of participants experiencing PONV and requiring antiemetics.	4, 8, 12, 24, and 48 hours after surgery
Length of hospital stay	Duration of hospitalization from surgery to discharge.	From surgery to discharge, up to 30 days
Patient satisfaction	Numerical rating scale satisfaction score. 0, not satisfied; 10, absolutely satisfied.	48 hours after surgery
Incidence of hemidiaphragmatic paralysis	Proportion of participants with phrenic nerve palsy after the block.	Within 24 hours after the nerve block
Postoperative blood glucose change	Change in blood glucose level on postoperative day 1 compared with baseline.	Postoperative day 1
Incidence of surgical and anesthetic complications	Surgical complications (surgical site infection, delayed wound healing) and anesthesia-related complications (nerve injury, local anesthetic systemic toxicity, catheter-related problems such as dislodgement, leakage, or infection).	Up to 30 days after surgery

Collaborators and Investigators

• Sponsor: Seoul National University Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): July 15, 2026
• Primary Completion (Estimated): June 15, 2027
• Study Completion (Estimated): July 15, 2027

Study Registration Dates

• First Submitted: July 5, 2026
• First Submitted That Met QC Criteria: July 9, 2026
• First Posted (Actual): July 13, 2026

Study Record Updates

• Last Update Posted (Actual): July 13, 2026
• Last Update Submitted That Met QC Criteria: July 9, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Dexamethasone; Postoperative analgesia; Shoulder surgery; Regional anesthesia; Enhanced recovery after surgery; Rotator cuff repair; Rebound pain; Multimodal analgesia; Non-inferiority trial; Interscalene brachial plexus block; Perineural catheter; Single-shot nerve block; Continuous peripheral nerve block; Intravenous dexamethasone
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Wounds and Injuries; Postoperative Complications; Pathologic Processes; Rupture; Tendon Injuries; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Rotator Cuff Injuries; Shoulder Injuries; Pain, Postoperative; Polycyclic Compounds; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Steroids, Fluorinated; Pregnadienetriols; Dexamethasone
• Other Study ID Numbers: 2605-154-1749

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared because the informed consent obtained from participants does not include provisions for data sharing with third parties.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No