Anterior Suprascapular Nerve Block is an Effective and Diaphragm Protective Approach for Arthroscopic Shoulder Surgery

Anterior Suprascapular Nerve Block is as Effective as Interscalene Nerve Block and Causes Less Diapragm Paralysis in Arthroscopic Shoulder Surgery

Interscalene block is still the gold standard in shoulder surgery analgesia. The most important side effect is diaphragm paralysis due to the phrenic nerve being affected. It may cause symptomatic dyspnea, especially in patients with limited respiratory capacity. There are studies showing that an effective analgesia, as much as the interscalene block can do, can be provided by blocking the suprascapular nerve in the neck region.

The aim of our study is to show that the anterior suprascapular block applied with ultra-low volume (5ml) in shoulder arthroscopy operations is at least as effective as the interscalene block and does not cause diaphragm paralysis.

Study Overview

• Status: Completed
• Conditions: Anterior Suprascapular Nerve Block; Diaphragm Paralysis Due to Local Anesthesia; Analgesia, Arthroscopic Shoulder Surgery
• Intervention / Treatment: Other: Evaluation of Diaphragm Movement

Detailed Description

Interscalene block is still the gold standard in shoulder surgery analgesia. The most important side effect is diaphragm paralysis due to the phrenic nerve being affected. It may cause symptomatic dyspnea, especially in patients with limited respiratory capacity. More distal brachial plexus blocks have been defined to avoid diaphragmatic paralysis . Thus, it is aimed to apply the local anesthetic drug further from the phrenic nerve. With the application of ultrasound, the amount of local anesthetic drug was reduced to less than 20 ml.

There are studies showing that an effective analgesia, as much as the interscalene block can do, can be provided by blocking the suprascapular nerve in the neck region. Although it has been shown in a cadaver study that the phrenic nerve can be stained after anterior suprascapular nerve block, the clinical effect is not fully known.

The effect of continuous local anesthetic drug administration on respiratory muscles through catheters placed in the peripheral nerve is another matter of concern. The method that will not affect the phrenic nerve at all and at the same time provide an effective analgesia is still under investigation.

The aim of our study is to show that the anterior suprascapular block applied with ultra-low volume (5ml) in shoulder arthroscopy operations is at least as effective as the interscalene block and does not cause diaphragm paralysis. One of the questions that our research aims to answer is how the continuous application of local anesthetic drugs affects the diaphragm muscle with the insertion of catheters in both regions.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Phase 4

Contacts and Locations

Study Locations

• Turkey
  • Sisli
    • Istanbul, Sisli, Turkey, 34365
      • VKV Amerikan Hastanesi

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 73 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patients > 18 years old
• American Society of Anesthesiology (ASA) score of 1-3
• Scheduled for elective surgery.

Exclusion Criteria:

• Patients with a condition that prevents peripheral nerve block
• Coagulopathies
• Chronic opioid use
• Stroke
• Polyneuropathy
• Cognitive dysfunction
• Communication difficulties
• Allergies to drugs used

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Interscalene block; patients will be placed in a semi-sitting position with their heads facing the opposite side. Linear ultrasound probe (GE Loqic P9 7-15 MHz) to detect the brachial plexus. At the cervical level 5-6, the posterior brachial plexus will be approached as "in-plane" from the posterior with the needle (Contiplex C, Braun) through the catheter. The nerve structure will be confirmed with stimulation in the upper extremity muscles with a nerve stimulator and 5 ml 0.5% Bupivacaine will be injected.	Other: Evaluation of Diaphragm Movement; Diaphragmatic movement will be evaluated with ultrasonography and a 5-2 MHz convex transducer will be used. The ultrasound probe is placed between the mid-clavicular line and the anterior axillary line by directing it vertically and slightly cranially. During quiet breathing and deep breathing, diaphragm movement will be measured. The reduction in diaphragm motion will be calculated as the difference (in percent) in diaphragm motion measured before and 30 minutes after the block. Each test will be done 3 times and the values will be averaged. A decrease between 75% and 100% will be defined as complete paresis, a decrease between 25% and 75% as partial paresis, and less than 25% decrease in diaphragmatic movement will be defined as no paresis. In order to investigate the effect of continuous local anesthetic drug administration on diaphragm movement via nerve catheter, the same procedure will be repeated 24 hours after surgery.
Active Comparator: Anterior suprascapular nerve block; patients will be placed in a semi-sitting position with their heads facing the opposite side. Linear ultrasound probe (GE Loqic P9 7-15 MHz) will be placed in the suprascapular region in a coronal oblique manner. The omohyoid muscle, under it the suprascapular nerve, the brachial plexus and the subclavian artery will be identified. The suprascapular nerve will be approached from the posterior as "in-plane" with a needle (Contiplex C, Braun) through the catheter. The nerve structure will be confirmed by stimulation in the supraspinous muscle with a nerve stimulator and 5 ml 0.5% Bupivacaine will be injected.	Other: Evaluation of Diaphragm Movement; Diaphragmatic movement will be evaluated with ultrasonography and a 5-2 MHz convex transducer will be used. The ultrasound probe is placed between the mid-clavicular line and the anterior axillary line by directing it vertically and slightly cranially. During quiet breathing and deep breathing, diaphragm movement will be measured. The reduction in diaphragm motion will be calculated as the difference (in percent) in diaphragm motion measured before and 30 minutes after the block. Each test will be done 3 times and the values will be averaged. A decrease between 75% and 100% will be defined as complete paresis, a decrease between 25% and 75% as partial paresis, and less than 25% decrease in diaphragmatic movement will be defined as no paresis. In order to investigate the effect of continuous local anesthetic drug administration on diaphragm movement via nerve catheter, the same procedure will be repeated 24 hours after surgery.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain rating	Measured by VAS. Postoperative 30 minutes	the first postoperative 30 minutes
Pain rating	Measured by VAS. Postoperative 6 hours	Postoperative 6 hours
Pain rating	Measured by VAS. Postoperative 12 hours	Postoperative 12 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diaphragmatic movements	Diaphragmatic movement will be evaluated with ultrasound. 30 minutes after the block application.	30 minutes after the block application.
Diaphragmatic movements	Diaphragmatic movement will be evaluated with ultrasound. 24 hours after the block application.	At the first postoperative 24 hours

Collaborators and Investigators

• Sponsor: Alper Tunga Dogan

Publications and helpful links

General Publications

• Tran DQ, Layera S, Bravo D, Cristi-Sanchez I, Bermudez L, Aliste J. Diaphragm-sparing nerve blocks for shoulder surgery, revisited. Reg Anesth Pain Med. 2019 Sep 20:rapm-2019-100908. doi: 10.1136/rapm-2019-100908. Online ahead of print.
• Bansal V, Shastri U, Canlas C, Gadsden JC. Diaphragm-Sparing Nerve Blocks for Shoulder Surgery: An Alternative Approach. Reg Anesth Pain Med. 2017 Jul/Aug;42(4):544-545. doi: 10.1097/AAP.0000000000000606. No abstract available.
• Auyong DB, Hanson NA, Joseph RS, Schmidt BE, Slee AE, Yuan SC. Comparison of Anterior Suprascapular, Supraclavicular, and Interscalene Nerve Block Approaches for Major Outpatient Arthroscopic Shoulder Surgery: A Randomized, Double-blind, Noninferiority Trial. Anesthesiology. 2018 Jul;129(1):47-57. doi: 10.1097/ALN.0000000000002208.
• Wiegel M, Moriggl B, Schwarzkopf P, Petroff D, Reske AW. Anterior Suprascapular Nerve Block Versus Interscalene Brachial Plexus Block for Shoulder Surgery in the Outpatient Setting: A Randomized Controlled Patient- and Assessor-Blinded Trial. Reg Anesth Pain Med. 2017 May/Jun;42(3):310-318. doi: 10.1097/AAP.0000000000000573.

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2020
• Primary Completion (Actual): March 15, 2021
• Study Completion (Actual): April 1, 2021

Study Registration Dates

• First Submitted: September 16, 2020
• First Submitted That Met QC Criteria: November 7, 2020
• First Posted (Actual): November 13, 2020

Study Record Updates

• Last Update Posted (Actual): November 30, 2021
• Last Update Submitted That Met QC Criteria: November 28, 2021
• Last Verified: November 1, 2021

More Information

Terms related to this study

• Keywords: arthroscopic shoulder surgery; Interscalene nerve block; Anterior suprascapular nerve block; Analgesia, postoperative; Diaphragm paralysis
• Additional Relevant MeSH Terms: Nervous System Diseases; Respiratory Tract Diseases; Respiration Disorders; Neurologic Manifestations; Respiratory Insufficiency; Paralysis; Respiratory Paralysis
• Other Study ID Numbers: 2020.1234

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