SPARK Study - Sympathetic PeriArterial Radial blocK Study
Duke University
Summary
The SPARK Study evaluates changes in peripheral sympathetic vasomotor activity following a targeted, ultrasound-guided periarterial sympathetic block of the distal radial artery in healthy volunteers. Autonomic reactivity will be assessed before and after the block using digit-specific pulse-amplitude index and infrared thermography during standardized cold pressor testing.
Eligibility
- Age range
- 18–50 years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Age 18-50 years * ASA physical status I-II * Able to understand and provide informed consent * Able to comply with study procedures and follow-up * Two hands with 5 intact digits and no significant upper extremity injury Exclusion Criteria: * Allergy to lidocaine or similar anesthetics * Allergy to adhesives or ultrasound gel * Neuromuscular, autonomic, or major vascular disorders affecting upper extremities * Peripheral neuropathy * Raynaud's phenomenon or digital ischemia * Coagulopathy or anticoagulation * Active skin infection near block site * Pregnancy * BMI \> 3…
Interventions
- DrugLidocaine 2%
Small-volume injection (5 mL) of 2% lidocaine around radial artery under ultrasound guidance.
Location
- Duke University Medical CenterDurham, North Carolina