Minimum Effective Volume for Selective Trunk Block

NCT04773405 | Completed

• 1 other identifier: SeTB MEV Ver 4
• Study Type: interventional
• Target: 25
• Locations: 1 country
• Sites: 1

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.

Conditions

Musculoskeletal Diseases or Conditions

Keywords

Selective Trunk nerve block

Outcome Measures

Primary Outcomes (3)

• Changes of sensory block of the upper extremity

  Sensation to coldness (ice) will be tested at C5 - Lateral (radial) side of the antecubital fossa (just proximal to elbow crease), C6 - Thumb, dorsal surface, proximal phalanx, C7 - middle finger, dorsal surface, proximal phalanx, C8 - Little finger, dorsal surface, proximal phalanx, and T1 - medial (ulnar) side of the antecubital) fossa, just proximal to the medial epicondyle of the humerus. Sensory block, defined as loss of sensation to cold (ice), will be graded using a numeric rating scale (NRS: 0-100, 100=normal sensation, 0=no sensation). A 3-point qualitative sensory score (0=no block, 1=analgesia/ patient can feel touch but not cold, and 2=anaesthesia / patient cannot feel touch) will be used. Onset of sensory block for each nerve will be defined as the time that it took to achieve a sensory block score of NRS =\<30 and Qualitative sensory score =1 .

  within 45 minutes after the block at 5 minutes interval

• Changes of motor blockade of the upper extremity

  motor blockade will be graded using a 3-point scale: 0=no block, 1=paresis and 2=paralysis. Motor blockade of each individual nerve in the anaesthetized upper extremity will be evaluated by testing C5 - elbow flexors, C6 - Wrist extensors, C7 - Elbow extensors, C8 - Finger flexors to the middle finger, and T1 - small finger abductors. Onset of Motor block for each nerve will be defined as the time it took to achieve motor score \>=1.

  within 45 minutes after the block at 5 minutes interval

• Readiness for surgery

  Overall sensory score of NRS =\<30 (NRS: 0-100; 100=normal sensation, 0=no sensation) and Qualitative sensory score =1 for each nerve; and motor scores \>=1 (3 point scale: 0=no block, 1=paresis, 2=paralysis) in all nerves tested. Overall the maximum composite sensory-motor score achievable is 20 points (2 points for each 5 sensory nerves tested and 2 points for each 5 motor nerves tested).

  within 45 minutes after the block at 5 minutes interval

Secondary Outcomes (1)

• Changes of the Diaphragmatic function

  Baseline (before block) and at 30 minutes after block

Study Arms (1)

Selective Trunk Block

OTHER

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.

Drug: a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 0.5% levobupivacaine

Interventions

a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 0.5% levobupivacaine 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.

Also known as: Selective trunk block

Selective Trunk Block

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.

You may not qualify if:

• 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.

Sponsors & Collaborators

• Chinese University of Hong Kong: lead

Study Sites (1)

Department of Anaesthesia & Intensive Care, Prince of Wales Hospital

Shatin, New Territories, Hong Kong

Location

Related Publications (1)

• 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.

  PMID: 40070288 DERIVED

MeSH Terms

Conditions

Musculoskeletal Diseases

Interventions

Lidocaine; Epinephrine; Levobupivacaine

Intervention Hierarchy (Ancestors)

Acetanilides; Anilides; Amides; Organic Chemicals; Aniline Compounds; Amines; Ethanolamines; Amino Alcohols; Alcohols; Biogenic Monoamines; Biogenic Amines; Catecholamines; Catechols; Phenols; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Bupivacaine

Study Officials

• Manoj K Karmakar, MD

  Chinese University of Hong Kong

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: February 25, 2021
• First Posted: February 26, 2021
• Study Start: March 10, 2021
• Primary Completion: November 12, 2021
• Study Completion: November 17, 2021
• Last Updated: November 18, 2021

Record last verified: 2021-11

Locations

HK (1)