Comparative Evaluation of Diaphragmatic Function Following Interscalene, Anterior Suprascapular, and Costoclavicular Nerve Blocks in Shoulder Surgery

NCT07671352 | Not Yet Recruiting Phase 4

• 1 other identifier: ANESTH50
• Study Type: interventional
• Target: 75
• Locations: 0 countries
• Sites: N/A

Brief Summary

Shoulder surgery causes significant postoperative pain, and ultrasound-guided regional anesthesia is central to its management. The interscalene block (ISB) is the gold standard but frequently causes phrenic nerve paralysis and hemi-diaphragmatic paresis, limiting its use in patients with reduced pulmonary reserve. The suprascapular (SSNB) and costoclavicular (CCB) blocks are proposed diaphragm-sparing alternatives, but data directly comparing all three are limited. This randomised, double-blinded trial will compare the incidence of hemi-diaphragmatic paresis among ultrasound-guided ISB, SSNB, and CCB in elective shoulder surgery. Seventy-five ASA I-II patients aged 18-70 will be allocated 1:1:1 to one block. The primary outcome is the incidence of hemi-diaphragmatic paresis, measured by ultrasound diaphragmatic excursion before induction and after recovery in the PACU. Secondary outcomes include postoperative pain, analgesic consumption, and patient satisfaction. The investigators hypothesise that SSNB and CCB will cause less hemidiaphragmatic paresis than ISB while providing comparable analgesia.

Conditions

Hemidiaphragmatic Paralysis; Postoperative Pain; Shoulder Surgery; Brachial Plexus Block

Keywords

Interscalene block; Suprascapular nerve block; Costoclavicular block; Diaphragmatic excursion; Ultrasound-guided regional anesthesia; Phrenic nerve palsy

Outcome Measures

Primary Outcomes (1)

• Incidence of hemi-diaphragmatic paresis

  Incidence of hemi-diaphragmatic paresis assessed by M-mode ultrasound measurement of diaphragmatic excursion, comparing post-block values to the pre-induction baseline. Hemi-diaphragmatic paresis is defined as a \>75% reduction in diaphragmatic excursion from baseline or paradoxical diaphragmatic movement (complete paresis); a 25-75% reduction is classified as partial paresis. Measured in the PACU after recovery of muscle power (train-of-four ratio ≥0.9). Reported as the number/percentage of participants with hemi-diaphragmatic paresis in each group.

  From pre-induction baseline to PACU assessment at train-of-four ratio ≥0.9 (up to approximately 24 hours after the block

Secondary Outcomes (2)

• Postoperative pain score at rest (static VAS)

  At 1, 3, 6, 12, and 24 hours postoperatively

• Patient satisfaction

  24 hours postoperatively

Study Arms (3)

Interscalene Block (ISB)

ACTIVE COMPARATOR

Ultrasound-guided interscalene brachial plexus block targeting the C5-C6 roots, performed approximately 1 hour before surgery. Injectate: 10 mL of 0.25% bupivacaine combined with dexmedetomidine 0.5 µg/kg.

Procedure: Ultrasound-guided interscalene brachial plexus block

Suprascapular Nerve Block (SSNB)

EXPERIMENTAL

Ultrasound-guided suprascapular nerve block was performed proximal to the transverse scapular ligament, approximately 1 hour before surgery. Injectate: 10 mL of 0.25% bupivacaine combined with dexmedetomidine 0.5 µg/kg.

Procedure: Ultrasound-guided suprascapular nerve block

Costoclavicular Block (CCB)

EXPERIMENTAL

Ultrasound-guided costoclavicular brachial plexus block targeting the brachial plexus cords in the costoclavicular space, approximately 1 hour before surgery. Injectate: 20 mL of 0.25% bupivacaine combined with dexmedetomidine 0.5 µg/kg.

Procedure: Ultrasound-guided costoclavicular brachial plexus block

Interventions

Ultrasound-guided suprascapular nerve block PROCEDURE

Ultrasound-guided suprascapular nerve block performed \~1 hour before surgery. A linear high-frequency probe in the supraclavicular region identifies the suprascapular nerve. A 22-gauge echogenic needle is advanced in-plane to the nerve proximal to the transverse scapular ligament, and 10 mL of 0.25% bupivacaine combined with dexmedetomidine 0.5 µg/kg is injected under real-time ultrasound, confirming circumferential spread.

Suprascapular Nerve Block (SSNB)

Ultrasound-guided costoclavicular brachial plexus block PROCEDURE

Ultrasound-guided costoclavicular brachial plexus block performed \~1 hour before surgery. With the operative arm abducted \~60°, a linear probe inferior to the mid-clavicle visualizes the three brachial plexus cords lateral to the axillary artery. An echogenic needle is advanced in-plane into the interfascial plane, and 20 mL of 0.25% bupivacaine combined with dexmedetomidine 0.5 µg/kg is injected with aspiration and ultrasound confirmation of homogeneous spread.

Costoclavicular Block (CCB)

Ultrasound-guided interscalene brachial plexus block PROCEDURE

Ultrasound-guided interscalene brachial plexus block performed \~1 hour before surgery. With the patient supine and head rotated contralaterally, a high-frequency linear transducer identifies the C5-C6 roots between the anterior and middle scalene muscles. Using an in-plane technique, 10 mL of 0.25% bupivacaine combined with dexmedetomidine 0.5 µg/kg is injected with frequent aspiration.

Interscalene Block (ISB)

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults of both sexes, aged 18 to 70 years American Society of Anesthesiologists (ASA) physical status I-II Scheduled for elective shoulder surgery

You may not qualify if:

• Pulmonary disease or baseline diaphragmatic dysfunction Refusal to provide informed consent Pre-existing neuropathy in the operated limb Allergy to local anesthetics Infection at the injection site Coagulopathy Pregnancy

Sponsors & Collaborators

• Menoufia University: lead

Related Publications (2)

• Renard Y, Grape S, Gonvers E, Rossel JB, Goetti P, Albrecht E. Respiratory impact of local anaesthetic volume after interscalene brachial plexus block with extrafascial injection: a randomised controlled double-blinded trial. Br J Anaesth. 2025 Apr;134(4):1153-1160. doi: 10.1016/j.bja.2024.12.010. Epub 2025 Jan 23.

  PMID: 39855930 RESULT

• Lee Y, Bang S, Chung J, Chae MS, Shin J. Costoclavicular block as a diaphragm-sparing nerve block for shoulder surgery: a randomized controlled trial. Korean J Anesthesiol. 2025 Feb;78(1):30-38. doi: 10.4097/kja.24595. Epub 2024 Dec 10.

  PMID: 39654085 RESULT

MeSH Terms

Conditions

Pain, Postoperative

Condition Hierarchy (Ancestors)

Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assisstant Lecture Menoufia University

Study Record Dates

• First Submitted: June 22, 2026
• First Posted: June 26, 2026
• Study Start: June 25, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): January 1, 2027
• Last Updated: June 26, 2026

Record last verified: 2026-06