右美托咪定对腰麻下膝关节置换术患者校正 QT间期和 Tp-e 间期的影响

The effect of dexmedetomidine on corrected QT and Tp-e interval in patients undergoing knee joint replacement with spinal anesthesia

目的研究右美托咪定对腰麻下膝关节置换术患者校正QT间期(QTc)和T波峰值至终点时间(Tp-e间期)的影响。方法 70例腰麻下行膝关节置换术的患者,年龄45~75岁,ASAⅠ或Ⅱ级,按随机数字表随机分为两组,每组35例。腰麻后15min,D组10min内给予静脉注射右美托咪定0.6μg/kg,然后以0.4μg·kg^(-1)·h^(-1)维持。C组注射同样剂量的生理盐水。记录腰麻前(T_0)、腰麻后5min(T_1)、10min(T_2)、15min(T_3)以及给予静脉注射后10min(T_4)、30min(T_5),60min(T_6)时QTc间期、Tp-e间期,记录术后24h内不良反应情况。结果与T_0时比较,两组患者T_1~T_3时QTc间期明显延长(P<0.05)。与T_3时比较,D组患者T_4~T_6时QTc间期明显缩短(P<0.05)。与C组比较,D组T_4、T_5时QTc间期明显缩短(P<0.05)。术后24h内两组不良反应差异无统计学意义。结论右美托咪定可以改善腰麻下行膝关节置换术患者导致的QTc间期延长。

Objective To investigate the effect of dexmedetomidine on corrected QT （QTc）and Tp-e interval from the peak of the T wave to the end of the T wave in patients undergoing knee joint replacement with spinal anesthesia.Methods Seventy patients 45-75 years,ASA Ⅰ or Ⅱ,who were scheduled to knee joint replacement with spinal anesthesia were divided into group C and group D ran-domly according to random number table （n=35 each group）.Dexmedetomidine 0.6 μg/kg was ad-minstered over 10 min intravenously,followed by a continuous infusion at a dose of 0.4 μg·kg-1 · h-1 in group D and volume-matched normal saline infusion was adminstered in group C 1 5 min after spinal anesthesia.Time points for QT （QTc）and Tp-e intervals and hemodynamic parameters were：before spinal anesthesia （T0 ）,5 （T1 ）,10 （T2 ）,and 1 5 （T3 ）minutes after spinal anesthesia and 10 （T4 ）,30 （T5 ）,and 60 minutes （T6 ）after infusion of dexmedetomidine or normal saline.The side effects in 24 h were also recorded.Results QTc intervals （T1-T3 ）in both groups were significantly prolonged compared with T0 （P 〈 0.05 ）.Compared with T3 ,QTc values in group D during T4-T6 were significantly shorter （P 〈0.05）.QTc interval in group D during T4-T5 was significantly shorter than that in group C （P 〈0.05）.There was no difference in side effects during postoperative 24 hours between two groups.Conclusion Dexmedetomidine could promote the return of a prolonged QTc in-terval in patients undergoing knee joint replacement with spinal anesthesia.