右美托咪定辅助臂丛神经阻滞诱导期的适宜负荷量研究

目的探讨右美托咪定辅助臂丛神经阻滞有效诱导期适宜负荷量。方法选取ASAⅠ~Ⅱ级上肢手术患者120例为观察组,随机分为D1、D2、D3和D4 4个亚组,每组30例,在麻醉平面稳定后分别微泵注射右美托咪定0.25、0.5、0.75和1.0μg/kg诱导10 min,同时对30例对照组患者诱导期仅注射0.9%生理盐水。记录各组泵药后10、30、60、90 min和120 min后血流动力学的变化、镇静效果及手术遗忘程度。结果观察组各亚组各时间点的Ramsay评分和遗忘程度明显高于对照组,其中以泵药后30 min和60 min时镇静效果最明显,且以D2和D3组镇静效果最佳(P0.05);泵药后30 min心率和平均动脉压低于对照组,差异有统计学意义(P0.05),但各组间呼吸频率比较差异无统计学意义(P0.05)。结论右美托咪定辅助臂丛神经阻滞的适宜剂量为0.5~0.75μg/kg,可达到最佳的镇静效果、稳定血流动力学和不引起呼吸抑制,具有显著临床价值。

Proper dosage of dexmedetomidine in brachial plexus block

Objective To study the proper dosage of dexmedetomidine in brachial plexus block. Methods 120 patients （ASA Ⅰ or Ⅱ） were randomly selected as observation group and divided into 4 groups （D1, D2, D3 and D4; n=30）. After the anesthesia got stable, the dosages of dexmedetomidine administrated in D1, D2, D3 and D4 groups were 0.25, 0.50,0.75 μg/kg and 1.00 μg/kg,respectively, while 30 cases in control group were given normal saline only. The administration time of each group was 10 minutes. Changes of hemodynamic, sedative effect and the oblivion extent of surgical operation were recorded after administration 10,30,60,90 min and 120 min. Results In observation groups （including D1, D2, D3 and D4 group）, the sedation score and oblivion extent after operation were higher than those in control group especially after 30 min and 60 min injection （P〈0.05）. And group D2 and D3 had the best sedative effect （P〈0.05）, and the HR and MAP were lower than those in control group （P〈0.05）; RR between the two groups had no significant differences（P〉0.05）. Conclusion The proper dosage of dexmedetomidine is ranging from 0.50 to 0.75 μg/kg for Brachial plexus block. It shows stable hemodynamic and offer the satisfied calmness without breath control in the operation. It is safe and can be widely applied.