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Musculoskeletal Diseases or ConditionsNCT04773405

Minimum Effective Volume for Selective Trunk Block

A study testing a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 0.5% levobupivacaine in people with Musculoskeletal Diseases or Conditions, run by Chinese University of Hong Kong at 1 site in Hong Kong.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial 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. Read more about this study

Who is it for?
Ages 18 to 75 years
Conditions the study is for
Musculoskeletal Diseases or Conditions
What is being tested?
a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 0.5% levobupivacaine
Could I receive a placebo?
No, everyone receives an active treatment
How many people
25 participants
Where
1 siteHong Kong
Study dates
10 Mar 2021to 17 Nov 2021
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 75 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • 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.

Who cannot join

  • 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.

Trial locations and contacts

1 site in 1 country.

Hong Kong1 site
  • Department of Anaesthesia & Intensive Care, Prince of Wales Hospital

    Shatin, New Territories

Other trials in Hong Kong

About this study

Official title: Minimum Effective Local Anaesthetic Volume of a 1:1 Mixture of 2% Lidocaine With 5ug/ml of Epinephrine and 0.5% Levobupivacaine Required for Ultrasound Guided Selective Trunk Block: A Dose Finding Study

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.

Read the 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.

Being tested
a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 0.5% levobupivacaine
Keywords
Selective Trunk nerve block
Medical subject headings
Musculoskeletal Diseases

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

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

    Also called Selective trunk block

    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.

Study groups in NCT04773405
Study groupRoleWhat they receive
Selective Trunk BlockOtherSelective 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.
Receives: Drug: a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 0.5% levobupivacaine

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. 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 .

    Measured: within 45 minutes after the block at 5 minutes interval

  2. 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.

    Measured: within 45 minutes after the block at 5 minutes interval

  3. 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).

    Measured: within 45 minutes after the block at 5 minutes interval

Secondary outcomes (1)
  1. Changes of the Diaphragmatic function

    Excursion of the right hemidiaphragm will be measured by ultrasound machine in supine position via the anterior subcostal route. The movement of the diaphragm will be measured in centimetres. The range of diaphragmatic excursion will be recorded from the resting expiratory position to deep inspiration (sigh test) as will be the range of diaphragmatic movement from resting expiratory position when quickly inspiring through the nose (sniff test). The decrease in diaphragmatic excursion will be calculated as the difference (in %) in diaphragmatic excursion measured before and 30 minutes after SeTB. Reduction in diaphragmatic excursion of more than 75%, or no movement, or paradoxical movement will be considered as complete paresis. Reduction in diaphragmatic excursion of both sigh and sniff test between 25% and 75% will be considered as partial paresis and diaphragmatic excursion of less than 25% will be considered as 'no paresis'.

    Measured: Baseline (before block) and at 30 minutes after block

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted26 Feb 2021
  2. Study start10 Mar 2021
  3. Primary completion12 Nov 2021
  4. Study completion17 Nov 2021

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
25 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04773405
Sponsor's protocol ID
SeTB MEV Ver 4
Status last verified
Nov 2021
First submitted
25 Feb 2021
Last updated
18 Nov 2021
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • 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.

    PubMed 40070288

Questions about this trial

What is this clinical trial studying?

A study testing a 1: 1 mixture of 2% lidocaine with 5ug/ml epinephrine and 0.5% levobupivacaine in people with Musculoskeletal Diseases or Conditions, run by Chinese University of Hong Kong at 1 site in Hong Kong.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 1 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 18 Nov 2021. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Changes of sensory block of the upper extremity (time frame: within 45 minutes after the block at 5 minutes interval). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04773405, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Nov 2021.

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