Clinical trial NCT02864602: IV Dexamethasone for Prolongation of Peripheral Nerve Block
Official title: A Volunteer Study to Determine the Optimal Dose of IV Dexamethasone Required for Prolongation of Peripheral Nerve Block
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE3
Conditions: Anesthesia, Conduction
Keywords: Regional anesthesia
Adjuvant
Dexamethasone
Lead sponsor: University Health Network, Toronto
Sponsor class: OTHER
First posted: 2016-08-12
Enrollment: 18
Sex: ALL
Minimum age (years): 18
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: This is a volunteer study examining the effect of different doses of IV dexamethasone on prolongation of median nerve block in the forearm.

Detailed description: 18 healthy volunteers aged 18-50 will be recruited (6 patients in each dosing group). Each volunteer will receive two forearm median nerve blocks separated by a two week washout period. One block will be conducted alongside an infusion of normal saline (control). The other block will be conducted alongside a randomised dose of IV dexamethasone (2, 4 or 8mg). The order of these interventions will be random. Blocks will be assessed quantitatively with cold and sharp sensation, electrical stimulation, quantitative sensory testing (thermal tolerance) and grip strength dynamometry. Measures or sensory and motor block including onset, intensity and duration will be compared between dosing groups.

Eligibility criteria: Inclusion Criteria:

* ASA 1 (normal healthy) volunteers.
* 18 - 50 years of age.
* 60 - 100kg weight.
* English speaking.
* Female volunteers of childbearing potential will be required to provide a negative pregnancy test before being allowed to participate.
* Females of child bearing potential must be willing to use medically acceptable birth control methods between study interventions and for a minimum of 2 weeks following the second nerve block.

Exclusion Criteria:

* Medical disorders (including bleeding disorders).
* Use of systemic steroids within 2 weeks of the study, prescription medications, live viral vaccines or any recreational drug use.
* Hypersensitivity to bupivacaine, dexamethasone or any component of saline.
* Contraindication to regional anesthetic block.
* Inability to provide informed consent.
* Baseline abnormality of hand sensation or motor function.
* Pregnancy / breast feeding.
* Individuals with mental health disorders (for example bipolar disorder or depression).
* Individuals with cataracts or glaucoma.
* Any known contraindication to IV dexamethasone as per the product monograph - bacteremia and systemic fungal infections, hypersensitivity to any of the products components, gastric and duodenal ulcers, certain viral infections i.e. varicella herpes genitalis.

Primary outcomes:
measure: The duration of sensory anesthesia and analgesia following median nerve block
timeFrame: This will be assessed for up to 12 hours following block
Secondary outcomes:
measure: The duration of motor block following median nerve block
timeFrame: This will be assessed for up to 12 hours following block
measure: Side effects related to nerve block or IV infusion of dexamethasone
timeFrame: Volunteers will be phoned at 24-36 hrs and then 7-10 days to ensure full resolution of the block
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Toronto Western Hospital
state: Ontario
Study officials:
References:
citation: Short A, El-Boghdadly K, Clarke H, Komaba T, Jin R, Chin KJ, Chan V. Effect of intravenous dexamethasone on the anaesthetic characteristics of peripheral nerve block: a double-blind, randomised controlled, dose-response volunteer study. Br J Anaesth. 2020 Jan;124(1):92-100. doi: 10.1016/j.bja.2019.08.029. Epub 2019 Nov 9.