Objective: To reduce the onset of 0.5% bupivacaine by adding 2% lidocaine with 0.5% bupivacaine for ultrasound-guided
and double stimulation technique at musculocutaneous and radial nerve for infraclavicular brachial plexus block.
Design: Prospective randomized double-blinded, controlled trial study.
Material and Method: 90 patients undergoing creation of arteriovenous fistula under ultrasound-guided infraclavicular
brachial plexus block were randomized into 2 groups. Gr. B (46 patients) received 0.5% bupivacaine 30 mL and Gr. BL (44
patients) received mixture of 0.5% bupivacaine 20 mL and 2% lidocaine 10 mL. The onset of sensory block were assessed by
response to pinprick (grading: 0 = no sensation, 1 = hypoesthesia, and 2 = normal sensation). Rescue analgesia during the operation, duration of sensory and motor blockade were recorded. Surgeon and patient satisfactions are also evaluated using 6-point scale (0 = dissatisfied to 5 = very satisfied).
Results: There were no significant difference in the onset time of either group. Duration of sensory and motor block was not
different. Surgeons’ and patients’ satisfaction were also not significantly different between the groups.
Conclusion: Mixing 2% lidocaine with 0.5% bupivacaine to the final concentration of 0.67% for lidocaine and 0.33% for
bupivacaine does not reduce the onset of ultrasound-guided infraclavicular brachial plexus block.

Keywords: Local anesthetics mixture, Ultrasound-guided infraclavicular brachial plexus block, Onset, Lidocaine, Bupivacaine, ESRD, AV fistula, Nerve stimulation