盐酸右美托咪定对老年椎管内麻醉手术患者术中应激反应的影响研究

目的：探讨盐酸右美托咪定对老年椎管内麻醉手术患者术中应激反应、血流动力学及术后躁动的影响。方法选择择期行下肢骨科手术的老年患者80例，ASAⅠ级或Ⅱ级，麻醉方式均为腰硬联合麻醉，患者随机分为观察组和对照组，每组40例。观察组于切皮前给予0摀．5μg／kg的盐酸右美托咪定泵注，维持剂量0．4μg· kg－1· h－1；对照组给予等量0．9％氯化钠溶液泵注。比较2组患者用药前（T1）及用药后10 min（T2）、20 min（T3）、30 min（T4）、60 min（T5）、术毕（T6）的应激反应及血流动力学指标变化情况。结果观察组T2～6时平均动脉压（MAP）均低于对照组，T5、T6时心率（HR）均低于对照组，差异有统计学意义（ P ＜0．05）；观察组T5、T6时血清去甲肾上腺素（NE）、肾上腺素（E）、皮质醇（Cor）水平均低于对照组，差异有统计学意义（ P ＜0．05）；观察组术后躁动发生率为12．5％显著低于对照组的32．5％，差异有统计学意义（ P ＜0．05）。结论盐酸右美托咪定减轻了老年椎管内麻醉手术患者术中应激反应程度，有利于维持血流动力学稳定，减少了术后躁动的发生，值得临床重视。

Effects of dexmedetomidine on stress reaction during intraspinal anesthesia in elderly patients

Objective To investigate the effects of dexmedetomidine on stress reaction , hemodynamics and postoperative restlessness during intraspinal anesthesia in elderly patients .Methods Eighty patients who were going to receive selective operation of lower limb orthopedics , with ASA gradeⅠor grade Ⅱ and anesthesia mode being lumbar epidural anesthesia ,were randomly divided into observation group and control group , with 40 patients in each group .Before skin incision the patients in observation group were given dexmedetomidine hydrochloride 0.5μg/kg by injection pump, with maintenance dose being 0.4μg· kg-1 · h-1,however,the patients in control group were given equivalence 0.9% sodium chloride solution by injection pump .The changes of stress reaction and hemodynamics indexes before medication (T1),after medication 10min (T2),20min (T3), 30min (T4) 60min (T5), eng of the operation (T6) were observed and compared between two groups.Results The MAP in observation group at T2,T6 was significantly lower than that in control group ,and HR in observation group at T5,T6 was significantly lower than that in control group ( P <0.05).The serum levels of NE, E and Cor in observation group at T5,T6 were significantly lower than those in control group ( P <0.05).The incidence of postoperative agitation in observation group was 12.5%, which was significantly lower than that (32.5%) in control group (P<0.05).Conclusion The dexmedetomidine hydrochloride can relieve the degree of stress reaction during intraspinal anesthesia in elderly patients , and reduce the incidence of postoperative restlessness , which is beneficial to keep the stabilization of hemodynamics .