Efficacy of forearm intravenous regional anesthesia throughcomparison of concentration and volume of lidocaine at adose of 2 mg/kg for hand and wrist surgeries

AimThis study aimed to evaluate the efficacy of intravenous regional anesthesia (IVRA) as regards volume versus concentration of lidocaine in surgeries.Patients and methodsThe study enrolled 46 patients of ASA physical status I and II, aged 18–65 years, undergoing IVRA using lidocaine 2% at a dose of 2 mg/kg plus fentanyl 1 μg/kg diluted with a volume of 25 ml normal saline [the concentration group (group C, n = 23)], or 2 mg/kg lidocaine 2% plus fentanyl 1 μg/kg diluted with a volume of 40 ml normal saline [the volume group (group V, n = 23)]. The total supplemental systemic fentanyl intraoperatively and rescue pethidine consumption during the first 4 h postoperatively were recorded. The success rate of the IVRA block was also recorded. First and second tourniquet pain times, as well as times of onset and recovery of sensory and motor block, were calculated. Visual analogue scale score for evaluation of the pain resulted from the surgical stimulation was recorded. The side effects of the drugs and complications of the technique were also recorded.ResultsIntraoperative supplemental fentanyl dose was significantly higher in group V compared with group C. The total pethidine consumption during the first 4 postoperative hours showed nonsignificant difference between patients of the two groups, with a mean of 48.27 ± 9.75 mg in group C versus 52.42 ± 13.83 mg in group V. Hemodynamic parameters such as heart rate and mean arterial pressure were comparable in the two groups. The time to first call of analgesia was significantly prolonged (P 0.05) in group C. Block characteristics were significantly better in group C. We did not encounter any serious side effect of any of the drugs used. ConclusionIVRA with lidocaine at a dose of 2 mg/kg in 25 ml volume of normal saline represented aneffective block and reduced the second tourniquet pain, increased the second tourniquet tolerance, and significantly decreased intraoperative supplemental fentanyl in comparisonwith the same dose in 40 ml volume of normal saline.