Local Anesthetic, Regional Anesthesia
Conditions
Brief summary
Choice of local anesthetics is the major determinant of the characteristics of a peripheral nerve block. Short acting local anesthetics while provides faster onset suffer from shorter duration. On the other hand, long acting local anesthetics while provides long duration suffered from long onset time. The ideal local anesthetics should provide faster nerve block onset while providing reasonable duration to provide sustained postoperative analgesia. Mixing short and long acting local anesthetics for nerve blocks may appear to be the solution however previous published studies have demonstrated similar onset time to long acting local anesthetics and with reduced duration. Recently, the London Health Sciences Centre established an ambulatory surgical centre. Fast onset peripheral nerve block is desirable. Previous studies have not looked at popliteal sciatic block and anecdotally we feel addition of short acting local anesthetics appear to speed up onset. We are therefore interested in conducting a randomize trial to determine whether mixing short and long acting local anesthetics can speed up onset of surgical quality block.
Interventions
DRUGRopivacaine and Lidocaine
Popliteal sciatic block using Ropivacaine 100 mg and Lidocaine 100 mg in 20 mL
DRUGRopivacaine 0,5%
Popliteal sciatic block using ropivacaine 0.5% 20 mL
Sponsors
London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adult patients (≥18 years old) * Scheduled for elective below-knee surgeries such as ankle arthroscopy, lower limb fracture fixation, toe surgeries, etc * Capable of providing informed consent
Exclusion criteria
* History of allergic reaction to local anesthetics * Pre-existing neurological disorders affecting lower limbs * Significant renal or hepatic impairment * Pregnancy or breastfeeding * Less than 60kg * Inability to provide informed consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time to complete sensory block | Tested every 2 min up to 60 min | The primary outcome is onset time for achievement of complete sensory block of the sciatic nerve determined via pinch test. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Duration of analgesia | up to 48 hours after discharge | Patient self reported time to onset of pain or analgesics |
| Pain score at 6 hour post-block | 6 hours after nerve block | Numeric rating scale of patient self-reported pain at 6 hour after block placement |
| Patient satisfaction | at 48 hour | 5 point categorical |
Contacts
Primary ContactCheng Lin
Outcome results
None listed