The Effect of Adding Dexmedetomidine as an Adjuvant to Lidocaine in Forearm Fracture Surgeries by Supraclavicular Block Procedure Under Ultrasound-Guided

To improve the brachial plexus block (BPB) performance, different compounds have been used as adjuvants to local analgesics.
The aim of the present study was to investigate the effects of adding DEX to lidocaine on effectiveness of nerve block, and postoperative pain in forearm fracture surgery by supraclavicular BPB undergoing ultrasound-guided.
This was a double-blinded randomized clinical trial conducted on 72 patients with ASA classes I and II, which were candidates for forearm fracture surgery. In group A, patients received 3 mg/kg of lidocaine 2%. In group B, patients received 3 mg/kg of lidocaine 2% and DEX (1 µg/kg). The ultrasound-guided supraclavicular BPB was performed in all patients. The onset of sensory and motor blocks were evaluated with pin prick test and modified Bromage scale, respectively. The sensory and motor block moment was recorded as the onset of the block. The first analgesic request time, total consumed analgesic, adverse effect, and hemodynamic parameters of patients were recorded. A visual analog scale (VAS) was used for recording the severity of pain.
The two groups showed no significant difference in the demographic variables. The onset of sensory and motor block in the DEX groups was shorter. The duration of sensory and motor block, and analgesic request was significantly longer than the control groups. Total analgesic consumption 24 hours after surgery in the DEX groups was significantly lower. Moreover, hemodynamic status of patients in both groups was stable and no significant difference was observed between groups. This study showed that DEX, as an adjuvant to lidocaine, improve the characteristics of supraclavicular BPB and decrease the postoperative pain.