两种剂量右美托咪定对成人心室复极不均一性的影响

Effect of Two Doses of Dexmedetomidine on Heterogeneity of Ventricular Repolarization in Adult Patients

目的:观察两种剂量右美托咪定静脉泵注对成人心室复极不均一性的影响。方法:选择全麻手术的患者40例随机均分为D1组和D2组,D1组患者给予右美托咪定负荷量0.6μg/kg泵注10 min后、再给予维持量0.3μg/(kg·h)持续泵注20 min,D2组患者给予右美托咪定负荷量1.0μg/kg泵注10 min后、再给予维持量0.5μg/(kg·h)持续泵注20 min;于右美托咪定泵注前(T0)、右美托咪定负荷量泵注10 min时(T1)、右美托咪定维持量泵注20 min时(T2)采集患者12导联心电图,测量计算QT间期和Tp-e间期,同时记录平均动脉压(MAP)和心率(HR)。结果:与组内T0时点比较,两组患者T1、T2时点HR减慢、QT间期延长及Tp-e间期缩短,D1组T2时点及D2组T1、T2时点MAP降低(P<0.05);与T1比较,D2组T2时点MAP降低、QT间期延长及Tp-e间期缩短(P<0.05);两组间相同时点的QT间期、Tp-e间期、MAP及HR比较,差异无统计学意义,P>0.05。结论:两种剂量右美托咪定持续泵注可延长心室复极时间,但不增大心室复极不均一性。

Objective： To observe the effect of two doses of dexmedetomidine （Dex） on heterogeneity of ventricular repolarization in adult patients. Methods： A total of 40 patients who had been scheduled for elective surgery under general anesthesia were evenly divided into two groups. Dexmedetomidine 1 group（ group D1 ）, loading dose of Dex was 0.6 μg/kg for 10 minutes and continual pumping dose was 0.3 μg/（ kg h） for 20 minutes. Dexmedetomidine 2 group （group D： ）, loading dose of Dex was 1 μg/kg for 10 minutes and continual pumping dose was 0.5μg/（ kg h） for 20 minutes. 12-lead ECG was carried out to calculate QT interval, Tp-e interval and MAP, HR were measured before Dex infusion （ T0 ） , after infusing loading dose of Dex （ T1 ） , and after infusing maintenance dose of Dex for 20 rain （ T2 ）. Results： Compared with To, HR and Tp-e interval decreased and QT interval increased in the two groups at T1 and T2, and the MAP decreased in D1 groups at T2 and in the D2 groups at T1 and T2 （P 〈 0.05 ）. Moreover, compared with T1 , QT interval increased and Tp-e interval shortened and MAP decreased in D2 group at T2 （ P 〈 0.05）. There was no statistical significance in MAP, HR, Tp-e interval and QT interval between two groups at different time points （ P 〉 0.05 ）. Conclusions ： Both dose of Dex prolong the ventricular repolarization duration, but do not increase heterogeneity of ventricular repolarization in adult patients.