Healthy Volunteers
Conditions
Keywords
US-guided peripheral nerve block, Anesthetics, Local, duration, Sensation, adductor canal block, lower limb, Adjuvants, Anesthesia
Brief summary
The purpose of this study is to investigate whether dexamethasone as an adjuvant to ropivacaine for adductor canal block increases duration of the sensory block, when controlling for a systemic effect using a paired design and bilateral blocks. The investigators hypothesize that adding dexamethasone to ropivacaine will prolong block duration compared with ropivacaine + placebo.
Interventions
Adductor canal block, single bolus
DRUGRopivacaine + placebo
Adductor canal block, single bolus
Sponsors
Rigshospitalet, Denmark
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
MALE
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* American Society of Anesthesiologists class 1 * Body Mass Index 18-30
Exclusion criteria
* Allergy to study medication * Earlier trauma or surgery to lower limb * Diabetes Mellitus * Alcohol or drug abuse * Daily intake of opioids or steroids last 4 weeks * Daily intake of any analgesics last 48 hours
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Difference in duration of sensory block between dexamethasone and placebo assessed as cold sensation with an alcohol swab | 0-36 hours | Duration is defined as time from block performance until recovery of cold sensation to an alcohol swab, assessed every hour post-block (and every half hour when pain scores during the tonic heat stimulation test is above 0, except at 2 and 3 hours post block where there will be a break and no assessments will be performed. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Difference between dexamethasone and placebo in the duration of a sensory block assessed by pin-prick | 0-36 hours | Duration is defined as time from block performance until recovery of normal sensation, assessed on the hour post block (except at 2 and 3 hours post block where there will be a break and no assessments will be performed). |
| Difference between dexamethasone and placebo in the duration of a sensory block assessed as maximum pain during a tonic heat stimulation test | 0-36 hours | Duration is defined as time from block performance until recovery of normal sensation, assessed on the hour post block (except at 2 and 3 hours post block where there will be a break and no assessments will be performed). Recovery of normal sensation is defined as VAS pain scores ± 10 mm of the pre-block value. |
| Difference between dexamethasone and placebo in the duration of a sensory block assessed as warmth detection threshold | 0-36 hours | Duration is defined as time from block performance until recovery of normal sensation, assessed on the hour post block (except at 2 and 3 hours post block where there will be a break and no assessments will be performed and only assessed if pain scores during tonic heat stimulation is above 0 ). Recovery of normal sensation is defined as detection thresholds of ± 2 degrees C of the pre-block value. |
| Difference between dexamethasone and placebo in the duration of a sensory block assessed as heat pain detection threshold | 0-36 hours | Duration is defined as time from block performance until recovery of normal sensation, assessed on the hour post block (except at 2 and 3 hours post block where there will be a break and no assessments will be performed and only assessed if pain scores during tonic heat stimulation is above 0 ). Recovery of normal sensation is defined as detection thresholds of ± 2 degrees C of the pre-block value. |
| Difference in maximum pain scores between dexamethasone and placebo during block and after recovery of normal sensation | 0-36 hours | Pain scores during a tonic heat stimulation will be compared at 4 h post block and 1 h after pain scores have returned to the pre-block values. |
Countries
Denmark
Outcome results
None listed