The Effect of Adding Dexmedetomidine to Lidocaine on Sensory and Motor Characteristics in Patients Undergoing Upper Extremity Fracture Surgery under Supraclavicular Block: A Randomized Controlled Clinical Trial

Background: Various drugs are used as adjuvants to improve the quality of supraclavicular block. Objective: This study aimed to investigate the effect of adding dexmedetomidine to lidocaine on the characteristics of supraclavicular block in upper limb surgeries. Methods: This double-blind controlled clinical trial was conducted on patients undergoing upper extremity fracture surgery under a supraclavicular block from 2016 to 2017. In the lidocaine-normal saline group, 30 ml of 1.5% lidocaine was prescribed. The lidocaine-dexmedetomidine group received 30 ml of 1.5% lidocaine with 1 μg/kg of dexmedetomidine. The block characteristics and intraoperative hemodynamic changes were recorded. Results: There was no statistically significant difference between the groups regarding the demographic parameters. The mean ages of the patients was 43.09 ± 10.92 years, and most were male. The mean onset time of sensory and motor block in the lidocaine-dexmedetomidine group was faster than the lidocaine-normal saline group, and the duration of the sensory-motor block and analgesia was longer in the lidocaine-dexmedetomidine group than the other group. These differences were statistically significant. In examining the changes in the hemodynamic parameters, a statistically significant difference was seen between the mentioned parameters at the nine assessment times in each group and between the two groups. Conclusion: This study showed that adding dexmedetomidine to lidocaine in the supraclavicular block accelerates the block's onset. It also increases the block and analgesia duration after surgery without causing significant side effects.