Background: This study aims to compare and evaluate the effect of
adding ketamine as an adjunct to lidocaine for intravenous regional anesthesia
(IVRA) on intraoperative and postoperative analgesia, the onset
and recovery times of sensory and motor block, and tourniquet pain.
Methods: Forty patients undergoing surgery of the hand or forearm under
IVRA were randomly assigned to receive lidocaine 3 mg/kg (group 1) or
lidocaine 3 mg/kg plus ketamine 50 mg (group 2) diluted to 40 mL with
normal saline. Assessment parameters included the onset and recovery
times of sensory and motor block, tourniquet pain, intraoperative hemodynamics,
surgeon and patient satisfaction, postoperative pain, time of first
analgesic request, total analgesic consumption, and adverse effects in the
first 24 hours postoperatively.
Results: Groups 1 and 2 were comparable in demographic and surgical
parameters. There were no differences between groups in intraoperative
hemodynamics, onset and recovery times of sensory and motor block, or
surgeon satisfaction index. Compared with group 1, group 2 patients
showed less tourniquet pain, prolonged time to first request for postoperative
rescue analgesia (5.5 ± 1.3 vs 20.4 ± 3.7 hours, P < 0.001), lower postoperative
diclofenac consumption (120.00 ± 45.23 vs 55.1 ± 0.00 mg,
P < 0.001), lower scores for postoperative pain as measured by the Verbal
Rating Scale, higher patient satisfaction index, and a nonsignificant difference
in the incidence of postoperative adverse effects between groups.
Conclusions: The addition of ketamine to lidocaine in patients receiving
IVRA significantly reduced intraoperative and postoperative analgesic requirements
and improved patient satisfaction without causing significant
adverse effects.
(Reg Anesth Pain Med 2014;39: 418–422)