右美托咪定对体外循环下瓣膜置换术患者心率、平均动脉压、心肌酶谱的影响

Effect of dexmedetomidine on HR,MAP in patients with valve replacement under extracorporeal circulation

目的:研究右美托咪定对体外循环(CPB)下瓣膜置换术患者的心率(HR)、平均动脉压(MAP)、心肌酶谱的影响。方法:选取2014年7月至2016年5月本院收治ASAⅡ~Ⅲ级拟行心脏瓣膜置换的择期手术患者90例,按随机数字表法将患者分为右美托咪定组(A组)和对照组(B组),每组45例。A组于麻醉诱导前缓慢静脉输注右美托咪定0.5μg·kg-1,其后以0.5μg·kg-1维持至手术结束。B组以等量生理盐水替代。分别抽取两组麻醉诱导前(T0)、CPB开始(T1)、主动脉开放时(T2)、停CPB时(T3)、手术结束时(T4)、术后2 h(T5)、术后24 h(T6)、术后48 h(T7)患者中心静脉血,采用ELISA法测定患者各时点血浆肌酸激酶同工酶(CK-MB)和肌钙蛋白I(c Tn I),并监测其HR、MAP值。结果:A组患者的MAP在T1时间点较术前明显升高(P<0.05),其升高的幅度比B组小(P<0.05),且与T2~T7时点A组患者的MAP值差异均无统计学意义(P>0.05),A组患者的HR在T2~T7时间点较术前升高(P<0.05),其升高幅度较B组小(P<0.05)。两组患者血清c Tn I值在T4~T7时间点较CBP前明显升高(P<0.05),但A组升高明显低于B组(P<0.05),血清CK-MB值在T3~T7时间点较CBP前明显升高(P<0.05),但A组升高明显低于B组(P<0.05)。结论:右美托咪定在CBP下心脏瓣膜置换术中可降低患者的HR、CK-MB和c Tn I,升高MAP,具有提高血流动力学的稳定及增强心肌的保护作用。

Objective： To explore the effect of dexmedetomidine on HR, MAP in patients with valve replacement under extracorporeal circulation. Methods： Ninety patients scheduled for elective surgery of heart valve replacement were selected during July 2014-May 2016 in our hospital, and randomly divided into group A and group B, 45 cases in each group. Group A were given slow intravenous injection of dexmedetomidine 0.5 μg·kg^-1 before the induction of anesthesia, followed by the micro- pump 0. 5 μg·kg^-1 maintaining until the end of surgery. Group B were given normal saline instead. Central venous blood was drawn in the two groups 10 min before induction of anesthesia （TO）, when CPB began （T1）, aortic declamping （T2）, stopping CPB （T3）, at the end of surgery （T4）, 2h （T5） afterwards, 24 h （T6） afterwards, 48 h （T7） afterwards, plasma creatine kinase （CK-MB） and troponin I （cTnI） were determined the by ELISA, and each time the patient＇s HR was measured, MAP. Results： MAP of patients in group A at T1 time point were significantly higher than that in group B （ P 〈 0.05 ）, the increased extend was smaller compared with group B （ P 〈 0.05 ）. Serum levels of cTnI values were significantly increased significantly at T4- T7 time （ P 〈 0.05 ） , the increased extend was higher than that in group B （ P 〈 0.05 ）, Serum CK-MB was significantly increased in T3-T7 time（P 〈 0.05 ）, the increased extend was higher than that in group B （ P 〈 0.05）. Conclusion ： Dexmedetomidine set at CBP valve replacement has a protective effect on myocardium.