Minimum Effective Local Anesthetic Volume for Ultrasound Guided Superior Trunk Block

NCT ID: NCT04941664

Last Updated: 2025-04-13

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 25 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-01-19
• Study Completion Date: 2026-08-31

Brief Summary

The objective of this study is to identify the minimum effective dosage of a commonly used local anaesthetic drug "levobupivacaine" required to produce an effective ultrasound guided (USG) superior trunk block (STB) in at least 90% of patients for shoulder arthroscopic surgeries.

Detailed Description

Shoulder arthroscopic surgery is one of the most commonly performed procedures worldwide, and associated with significant postoperative pain. Currently, such surgery is performed either under general anaesthesia or under Interscalene brachial plexus block (ISBPB), which is a regional anaesthesia technique. However, ISBPB is associated with the highest incidence of hemi-diaphragmatic palsy of the operative side. Since majority of the innervation to the shoulder arises from or passes through the superior trunk of the brachial plexus, superior trunk block has been shown to have lesser impact on the phrenic nerve and it has been gaining popularity worldwide. Ultrasound is widely used for brachial plexus block and current evidence indicates that it is feasible to accurately identify majority of the main components of the brachial plexus above the clavicle, including the three trunks (superior, middle, and inferior trunks). However, there are no data describing an optimal volume of local anaesthetic for superior trunk block. The aim of this study is to identify the minimum effective dosage of a commonly used local anaesthetic drug "levobupivacaine" required to produce an effective ultrasound guided (USG) superior trunk block (STB) in at least 90% of patients for shoulder arthroscopic surgeries.

Conditions

Musculoskeletal Diseases or Conditions

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Levobupivacaine

Superior trunk nerve block will be done under ultrasound guidance to patients scheduled for shoulder surgeries. Local anesthetic agent (0.5% levobupivacaine) 8ml will be injected at the superior trunk of the brachial plexus in order to produce surgical anesthesia or analgesia for shoulder surgeries.

Group Type: OTHER

0.5% levobupivacaine

Intervention Type: DRUG

This study adopts a "Modified Narayana rule (MNR)", a sequential up-and-down pharmacodynamics method (UDM) to estimate the minimum effective local anesthetic volume of 90% (MELVA90) of cases of the aforementioned local anesthetic (LA), in order to produce the surgical anesthesia of the patients scheduled for shoulder surgeries. Based on the principal investigator's clinical experience, the initial volume of 8ml will be used. Depending on the success or failure of the superior trunk block, which is defined as the readiness for surgery at 30 minutes after the block, the volume for the next patient will be adjusted up or down by 2ml. The upper dose limit of the study to minimize the potential for local anesthetic systemic toxicity will be 16ml and the lower dose limit will be 4ml, which will be of no clinical importance.

Interventions

0.5% levobupivacaine

This study adopts a "Modified Narayana rule (MNR)", a sequential up-and-down pharmacodynamics method (UDM) to estimate the minimum effective local anesthetic volume of 90% (MELVA90) of cases of the aforementioned local anesthetic (LA), in order to produce the surgical anesthesia of the patients scheduled for shoulder surgeries. Based on the principal investigator's clinical experience, the initial volume of 8ml will be used. Depending on the success or failure of the superior trunk block, which is defined as the readiness for surgery at 30 minutes after the block, the volume for the next patient will be adjusted up or down by 2ml. The upper dose limit of the study to minimize the potential for local anesthetic systemic toxicity will be 16ml and the lower dose limit will be 4ml, which will be of no clinical importance.

Intervention Type: DRUG

Other Intervention Names

Peripheral nerve block

Eligibility Criteria

Inclusion Criteria

• American Society of Anesthesiologists (ASA) physical status I-III scheduled to undergo elective upper shoulder arthroscopic rotator cuff repair procedure

Exclusion Criteria

• Patient refusal
• pregnancy
• skin infection at the site of block placement
• history of allergy to local anaesthetic drugs
• bleeding tendency or with evidence of coagulopathy
• pre-existing neurological deficit or neuromuscular disease.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 75 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Chinese University of Hong Kong

OTHER

Sponsor Role: lead

Responsible Party

Prof Manoj K Karmakar

Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Manoj K Karmakar, MD

Role: PRINCIPAL_INVESTIGATOR

Chinese University of Hong Kong

Locations

Department of Anaesthesia & Intensive Care, Prince of Wales Hospital

Shatin, New Territories, Hong Kong

Site Status: RECRUITING

Countries

Hong Kong

Central Contacts

Ayla Wong, RN, BN

Role: CONTACT

aylawong@cuhk.edu.hk

+85235056157

Facility Contacts

Winnie Samy, RN, BN, MSc

Role: primary

wsamy@cuhk.edu.hk

+85235052734

Other Identifiers

CREC.2021.184-T

Identifier Type: -

Identifier Source: org_study_id