Evaluating the Effects of Lidocaine Alone Versus Combination of Lidocaine with Pethidine for the Intravenous Regional Anesthesia in Upper Limb Soft Tissue Surgery

Intravenous regional anesthesia (IVRA) has been used as a common anesthetic technique for several types of operations. However, there are various concerns regarding the efficacy of this anesthetic method. The aim of this study was to evaluate the effects of lidocaine alone versus concomitant use of lidocaine and pethidine for the IVRA in upper limb surgery.

In this randomized, double-blind, controlled clinical, 50 eligible individuals were randomly divided to receive either a combination of 1.5 mg/kg lidocaine 2% and 1.5 mg/kg pethidine or placebo (3 mg/kg lidocaine 2%) for IVRA. After the surgery, the onsets and durations of sensory and motor block, the pain intensity in recovery room, the subjects' first demand of morphine, and the total amount of morphine injected within 24 hours were measured.

The combination of lidocaine and pethidine was significantly effective in accelerating the onset of both sensory and motor blocks [(P=0.001), (P=0.001), respectively]. However, no differences were found between groups in sensory and motor block durations after surgery. Intervention with lidocaine plus pethidine caused a significant reduction of the pain intensity in recovery room (P=0.02). Also, concomitant use of lidocaine and pethidine led to a longer time of the first demand of morphine (P=0.04). Moreover, the total amount of morphine injected within 24 hours after surgery was considerably lower in individuals treated by lidocaine plus pethidine (P=0.003).

The results of the current study suggest that adding pethidine to lidocaine can be considered as an appropriate approach for better management of IVRA.