Comparing three doses of perineural dexmedetomidine for infraclavicular nerve block

A Randomized Comparison Between 0.67 mcg/kg, 1 mcg/kg, and 1.33 mcg/kg of Perineural Dexmedetomidine for Ultrasound-Guided Infraclavicular Block

This study will see if adding one of three doses of dexmedetomidine to a local anesthetic makes a nerve block last longer for adults having elbow-or-below arm surgery.

Quick facts

• Phase: PHASE2
• Study type: Interventional
• Enrollment: 69 (estimated)
• Ages: 18 Years to 75 Years
• Sex: All
• Sponsor: McGill University Health Centre/Research Institute of the McGill University Health Centre (other)
• Locations: 1 site (Montreal, Quebec)
• Trial ID: NCT07249827 on ClinicalTrials.gov

What this trial studies

In a randomized, blinded Phase 2 trial at McGill University Health Centre, 69 adults having upper-extremity (elbow and below) surgery will receive an ultrasound-guided infraclavicular brachial plexus block with a fixed local anesthetic mixture and one of three perineural dexmedetomidine doses (0.67, 1.0, or 1.33 mcg/kg). Blocks will be performed preoperatively using 35 mL of a standardized lidocaine/bupivacaine/epinephrine solution plus dexamethasone, and the injectate will be prepared by a research assistant to maintain blinding of operator, patient, and assessor. Patients are randomized to dose groups and the primary outcome is duration of motor block, measured from end of injection to return of hand and finger movement. The hypothesis is that each higher dose will extend motor block duration by about 15% compared with the next lower dose.

Who should consider this trial

Good fit: Ideal candidates are adults 18–75 years old with BMI 18–35 kg/m2, ASA physical status 1–3, able to consent, and scheduled for upper limb surgery at or below the elbow at the McGill University Health Centre.

Not a fit: Patients with contraindications such as allergy to dexmedetomidine or local anesthetic, recent exposure to dexmedetomidine, pre-existing neuropathy, significant renal or hepatic failure, pregnancy, or who cannot receive care at the study site are not expected to benefit from participation.

Why it matters

Potential benefit: If successful, the optimal dexmedetomidine dose could prolong motor and overall block duration, potentially improving postoperative pain control and reducing early opioid needs.

How similar studies have performed: Previous trials of perineural dexmedetomidine as an adjuvant have often shown prolonged block durations, but optimal dosing and definitive safety data remain uncertain.

Eligibility criteria

Inclusion Criteria:

* patients undergoing upper limb surgery at or below the elbow
* age between 18 and 75 years
* American Society of Anesthesiologists classification 1-3
* body mass index between 18 and 35 kg/m2

Exclusion Criteria:

* adults who are unable to give their own consent
* allergy or contraindication to dexmedetomidine
* exposure to dexmedetomidine during the previous 48 hrs
* pre-existing neuropathy (assessed by history and physical examination)
* coagulopathy (assessed by history and physical examination and, if deemed clinically necessary, by blood workup i.e. platelets ≤ 100, International Normalized Ratio ≥ 1.4 or partial prothrombin time ≥ 50)
* renal failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work-up i.e. creatinine. eGFR \< 90)
* hepatic failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work-up i.e. transaminases ≥ 100)
* allergy to LA
* pregnancy (as institutional policy, female patients with childbearing potential undergoing non urgent surgery are tested preoperatively for pregnancy with blood tests)
* breast feeding
* prior surgery in the infraclavicular region
* chronic pain syndromes requiring opioid intake at home

Where this trial is running

Montreal, Quebec

• McGill University Health Centre — Montreal, Quebec, Canada (RECRUITING)

Study contacts

• Principal investigator: Julián Aliste, MD — McGill University Health Centre/Research Institute of the McGill University Health Centre
• Study coordinator: Julián Aliste, MD

Conditions: Analgesia, Pain, Acute, Upper Extremity Surgery, Nerve Block, Acute pain, Brachial plexus, Brachial plexus block, Postoperative pain