Minimum Effective Volume for Selective Trunk Block

NCT ID: NCT04773405

Last Updated: 2021-11-18

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 25 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2021-03-10
• Study Completion Date: 2021-11-17

Brief Summary

The objective of this study is to identify the minimum effective dosage of a mixture of two local anaesthetic drugs called 'levobupivacaine' and 'lignocaine with epinephrine" used to produce an effective ultrasound guided selective trunk block for surgical anaesthesia of the upper limb.

Detailed Description

Ultrasound is widely used for brachial plexus block (BPB) 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. Since majority of the innervation to the upper extremity, including the shoulder, arises from the three trunks (superior, middle and inferior) of the brachial plexus, so targeted injections of the individual trunks of the brachial plexus under ultrasound guidance will produce surgical anaesthesia of the entire upper extremity (C5-T1). Principal Investigator refers to this novel technique "selective trunk block" (SeTB) and the preliminary experience with SeTB for surgical anaesthesia of the entire upper extremity has been very encouraging. Currently there are no data describing an optimal dose or volume of local anaesthetic for SeTB. The aim of this study is to identify the minimum dosage of 1:1 mixture of 'levobupivacaine' and "lignocaine with epinephrine" required to produce effective surgical anaesthesia in at least 90% of patients presented for upper limb surgery.

Conditions

Musculoskeletal Diseases or Conditions

Keywords

Selective Trunk nerve block

Study Design

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

Study Groups

Selective Trunk Block

Selective trunk block will be done under ultrasound guidance to patients scheduled for upper extremities surgeries. Local anaesthetic agents (a 1:1 mixture of 2% lidocaine with 5ug/ml of epinephrine and 0.5% levobupivacaine) will be injected at the superior, middle, and inferior trunks of the brachial plexus in order to anaesthetize the whole upper limb.

Group Type: OTHER

a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 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% (MELAV90) of cases of the aforementioned local anaesthetic (LA) mixture, in order to produce the surgical anaesthesia of the whole upper extremity of the patients scheduled for upper limb surgeries. Based on the principal investigator's clinical experience, the initial volume of 21ml will be used. Depending on the success or failure of the SeTB, 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 3ml (1ml for each trunk of brachial plexus located above the clavicle). The upper dose limit of the study to minimize the potential for local anaesthetic systemic toxicity will be 30ml and the lower dose limit will be 12ml, which will be of no clinical importance.

Interventions

a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 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% (MELAV90) of cases of the aforementioned local anaesthetic (LA) mixture, in order to produce the surgical anaesthesia of the whole upper extremity of the patients scheduled for upper limb surgeries. Based on the principal investigator's clinical experience, the initial volume of 21ml will be used. Depending on the success or failure of the SeTB, 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 3ml (1ml for each trunk of brachial plexus located above the clavicle). The upper dose limit of the study to minimize the potential for local anaesthetic systemic toxicity will be 30ml and the lower dose limit will be 12ml, which will be of no clinical importance.

Intervention Type: DRUG

Other Intervention Names

Selective trunk block

Eligibility Criteria

Inclusion Criteria

• American Society of Anesthesiologists (ASA) physical status I-III scheduled to undergo elective upper extremity surgery involving the proximal humerus to distal hand or surgery involving any combination of these regions.

Exclusion Criteria

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

Countries

Hong Kong

References

Sivakumar RK, Karmakar MK, Wong RSL, Samy W. Minimum effective volume 90% for ultrasound-guided selective trunk block: A quantal bioassay. Eur J Anaesthesiol. 2025 Sep 1;42(9):800-807. doi: 10.1097/EJA.0000000000002160. Epub 2025 Mar 11.

Reference Type: DERIVED

PMID: 40070288 (View on PubMed)

Other Identifiers

SeTB MEV Ver 4

Identifier Type: -

Identifier Source: org_study_id