右旋美托咪定输注对瓣膜置换术患者血流动力学及应激反应的影响

The effect of dexmedetomidine on hemodynamics and stress reaction in patients undergoing cardiac valve replacement surgery

目的观察在瓣膜置换手术麻醉期间持续输注右旋美托咪定（DEX）的安全性及对患者血流动力学及应激反应的影响。方法24例心脏瓣膜病换瓣手术患者随机分成两组，研究组（n=12）及对照组（n=12）。研究组麻醉诱导前给予DEX（0．5ug／kg，10min泵注）后以维持量（每小时0．5ug/kg）泵注至手术结束，在负荷量输注结束后开始麻醉诱导；对照组泵注相同容量0．9％氯化钠，两组患者的麻醉诱导和维持药物相同。分别在T0,T1、T2、T3、T4、T5及T6时刻监测患者的HR、MAP、CVP、CO、CI、SV、SVI及BIS值。并在T0、T3、T4、T5、T6时点测定血清皮质醇、血糖和血乳酸值浓度。结果两组患者自动复跳例数及肾上腺素的使用剂量差异无统计学意义。与B组比较，A组在T1、T2时点的MAP、HR、BIS值明显降低（P〈0．05）；在T3、T4时点B组的MAP和HR较A组明显升高（P〈0．05）；在T5、T6时点，A组的HR、CO、CI均低于B组（P〈0．05）。与T0比较，在T5、T6时点A、B两组的血清皮质醇、血糖和血乳酸浓度明显升高（P〈0．01）；A组的血清皮质醇浓度在T5、T6时分别为（19．4±4．9）、（19．8±4．6ug/dl，B组的血清皮质醇浓度在T5、T6时分别为（25．4±5．1）、（24．2±5．3）ug／dl；与B组比较，A组血清皮质醇浓度在T5、T6时点明显降低（P〈0．05）。A组的血糖浓度在L时点明显低于B组（P〈0．05）。结论右旋美托咪定可以安全地用于心脏瓣膜置换手术，期间血流动力学稳定，并一定程度可抑制心脏瓣膜置换手术引起的应激反府。

Objective To evaluate the effect of dexmedetomidine on hemodynamics and stress reaction in patients undergoing cardiac valve replacement surgery. Methods Twenty four patients undergoing cardiac valve replacement surgery were allocated randomly into study group （ group A, n = 12 ） and control group （ group B, n = 12 ）. Dexmedetomidine [ 0. 5 ug/kg bolus and infusion at a rate of 0. 5 ug/（kg.h） ] was administered to patients in study group. Heart rate （HR）, mean arterial pressure （MAP）, central venous pressure （CVP）, cardiac output （CO）, cardiac index （CI）, stroke volume （SV）, stroke volume index （SVI） and bispeetral index （BIS） were recorded before administration of dexmedetomidine （T0）, 5 minutes after administration of dexmedetomidine （T1 ）, 10 minutes after administration of dexmedetomidine （T2 ）, 1 minute after tracheal intubation （T3 ）, iminute after sternal saw （ T4 ）, 15 minutes after the termination of cardiopulmonary bypass （CPB） （T5 ） and at the end of operation （T6 ）. Serum cortisol, blood glucose and blood lactate concentration were measured at T0, T3 , T4, T5 and T6. Results MAP, HR and BIS were significantly lower in group A compared those of group B at T1 , T2 （ P 〈 0. 05）. MAP, HR were significantly higher in group B compared those of group A at T3 , T4 （ P 〈 0. 05 ）. HR, CO, CI were significantly lower in group A compared those of group B at T5, T6 （P 〈 0. 05 ）. Serum cortisol, blood glucose and blood lactate concentration were significantly increased at T5 and T6 compared those at To in both groups （ P 〈 0. 01 ）. Serum cortisol concentration was （ 19.4 ± 4. 9 ） ug/dl, （19. 8 ±4. 6） ug/dl at Ts, T6 in group A, Serum cortisol concentration was （25.4 ±5.1） ug/dl, （24. 2 ± 5.3） ug/dl at T5 , T6 in group B, Serum cortisol concentration was significantly lower in group A compared that of group B at T5, T6 （P 〈 0. 05 ）. Blood glucose concentration was significantly lower in group A compared that of group B at T6 （P 〈 0. 05）. Conclusion Dexmedetomidine can reduce sympathetic nervous over excitement and stress reaction and maintain hemodynamic stability in cardiac surgery.