Background: Ultrasound-guided for regional anesthesia offers many poten- tial benefits in the emergency setting. Analgesia can be explicitly targeted to the region of pain and provide relief for many hours and decrease needing to the large volume of local anesthetic. The aim of the work: Comparing the ef- ficacy of dexmedetomidine when used as an adjuvant to bupivacaine in su- praclavicular brachial plexus blocks on the onset of sensory, motor blockade and postoperative analgesia. Patients and methods: This prospective, ran- domized, single-blind clinical study conducted on 60 patients underwent up- per limb surgery done by ultrasound-guided supraclavicular brachial plexus block; these patients allocated into two equal groups: Group I (control) re- ceived 20 ccs (19 cc bupivacaine 0.5% + 1 cc saline), Group II received 20 cc
(19 cc bupivacaine 0.5% + 1 cc volume of Dexmedetomidine 1 ug/kg). Re- sults: Demographic data and surgical characteristics were comparable in both groups. The onset times for sensory and motor blocks were significantly shorter in Group II than Group I (P < 0.001), while the duration of blocks was considerably longer (P < 0.001) in Group II. Except for the first record- ings (at 0, 5, and 10 min), heart rate levels in Group II were significantly low- er (P < 0.001). MBP levels in Group II at 15, 30, 45, 60, 90 and 120 min were significantly lower than in Group I (P < 0.001). The duration of analgesia (DOA) was significantly longer in Group II than Group I (P < 0.001). As re- gards to the visual Analouge score, there is a highly significant difference at 6 hours, 8 hours and 10 hours in Group II than Group I. Conclusion: We recommend adding Dexmedetomidine to local anesthetics in peripheral nerve blocks to take advantage of the prolonged time of both sensory and motor blocks and prolonged postoperative analgesia.