Background. Brachial plexus block is frequently recommended for upper limb surgeries. Many drugs have been used as adjuvants to prolong the duration of the block. This study aimed to assess the effect of dexmedetomidine with bupivacaine combination and only bupivacaine on sensory and motor block duration time, pain score, and hemodynamic variations in the supraclavicular block in upper extremity orthopedic surgery. Methods. This prospective, double-blind clinical trial study was conducted on 60 patients, 20 to 60 years old. Patients were candidates for upper extremity orthopedic surgeries. The sensory and motor block were evaluated by using the pinprick method and the modified Bromage scale. The postoperative pain was assessed by utilizing a visual analog scale. Results. The mean onset time of sensory and motor block in patients receiving only bupivacaine was, respectively, 31.03 ± 9.65 min and 24.66 ± 9.2 min, and in the dexmedetomidine receiving group, it was about 21.36 ± 8.34 min and 15.93 ± 6.36 minutes. The changes in heart rate and mean arterial blood pressure were similar in both groups. The duration of sensory and motor block and the time of the first analgesia request in the intervention group were longer. Postoperative pain was lower in the intervention group for 24 hours ( = 0.001). Conclusion. Dexmedetomidine plus bupivacaine reduced the onset time of sense and motor blocks and increased numbness and immobility duration. Also, dexmedetomidine reduced postoperative pain significantly with the use of bupivacaine for supraclavicular blocks. Trial Registration. IRCT, IRCT20160430027677N15. Registered 05/28/2019, https://www.irct.ir/trial/39463.

中文翻译：

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右美托咪定联合布比卡因对锁骨上阻滞的感觉和运动阻滞时间及疼痛评分的影响

背景。臂丛神经阻滞常被推荐用于上肢手术。许多药物已被用作佐剂，以延长阻断作用的持续时间。本研究旨在评估右美托咪定联合布比卡因和仅布比卡因对上肢整形外科手术中感觉和运动阻滞持续时间，疼痛评分以及锁骨上阻滞的血流动力学变化的影响。方法。这项前瞻性，双盲临床试验研究针对60名20至60岁的患者进行。患者是上肢骨科手术的候选人。通过使用针刺法和改良的Bromage量表评估感觉和运动阻滞。通过使用视觉模拟量表评估术后疼痛。结果。仅接受布比卡因的患者的感觉和运动阻滞的平均发作时间分别为31.03±9.65分钟和24.66±9.2分钟，而右美托咪定接受组的平均发作时间分别为21.36±8.34分钟和15.93±6.36分钟。两组的心率和平均动脉血压的变化相似。干预组感觉和运动阻滞的持续时间以及首次镇痛的时间较长。干预组的术后24小时疼痛减轻（ = 0.001）。结论。右美托咪定加布比卡因减少了感觉和运动阻滞的发作时间，并增加了麻木和固定时间。此外，右旋美托咪定通过使用布比卡因治疗锁骨上阻滞可显着减轻术后疼痛。试用注册。IRCT，IRCT20160430027677N15。注册于05/28/2019，https://www.irct.ir/trial/39463。