右美托咪定和咪达唑仑对ICU 老年患者机械通气的镇静效果研究

Sedative efficiency of Dexmedetomidine or Midazolam on mechanical ventilation with BIS in elder patients in ICU

摘要:

目的 探讨脑电双频谱指数（BIS）监测下持续静脉泵注右美托咪定和咪达唑仑对老年心脏手术患者术后机械通气的镇静效果。方法 选取择期行瓣膜置换手术，并于术后带气管导管进入重症加强护理病房（ICU）的老年患者68 例，平均随机分为右美托咪定组和咪达唑仑组。右美托咪定组患者首先静脉泵注0.5μg/kg 右美托咪定10 min，然后以0.2μg/（kg·h）的速度持续静脉泵注。咪达唑仑组患者首先静脉泵入咪达唑仑负荷剂量0.06 mg/kg，然后以0.4 mg/（kg·h）的速度持续静脉泵注。记录泵注镇静药物前，以及泵注药物后1、2 和3 h 两组患者各时间点的平均动脉压（MAP）、呼吸频率（RR）、脉搏氧饱和度（SpO2）、心率（HR）、改良警觉／镇静评分（MOAA/S）、BIS、脱机时间及不良反应。药物泵注3 h 后，将BIS 值控制在61 ～ 75，并根据BIS 值调整药物泵注的速度。结果 两组患者在实施不同镇静方案后各时间点的MAP、RR、SpO2、HR、MOAA/S 评分比较，差异无统计学意义（P >0.05）。与镇静前相比，两组患者RR、HR 降低，MOAA/S 升高，右美托咪定组患者实施镇静后各时间点的BIS、MOAA/S 高于咪达唑仑组，低血压、心动过缓等不良反应的发生率低于咪达唑仑组，右美托咪定组患者自转入ICU 至开始脱机的时间、脱机时间短于咪达唑仑组（P <0.05）。结论 右美托咪定和咪达唑仑持续静脉泵注对ICU 老年心脏手术患者术后持续机械通气具有良好的镇静效果，但在等效镇静水平下，右美托咪定脱机时间更短，不良反应发生率更低。

Abstract:

Objective To evaluate the sedative efficiency of continuous infusion of Dexmedetomidine or Midazolam on mechanical ventilation with BIS in elder patients who underwent cardiac surgery. Methods Sixtyeight elder patients who underwent mechanical ventilation after cardiac surgery were admitted to ICU and randomly assigned to Dexmedetomidine group (group D) and Midazolam group (group M). In the Dexmedetomidine group,Dexmedetomidine was first intravenously infused at a dosage of 0.5 μg/kg for 10 min and followed by continuous infusion at a rate of 0.2 μg/(kg?h). In the Midazolam group, Midazolam was intravenously infused at a loading dosage of 0.06 mg/kg, then continued at a rate of 0.4 mg/(kg?h). MAP, RR, SpO2, HR, MOAA/S, BIS, off-machine ventilation time and adverse reactions were compared between the two groups before medication, 1, 2 and 3 h after infusion. BIS index was maintained between 61 and 75 during ventilation procedure in every patient after sedatives were infused for 3 h. Results The differences of MAP, RR, SpO2, HR and MOAA/S at the corresponding time points during mechanical ventilation procedure were not statistically significant between the two groups (P > 0.05).Compared with the premedication values, RR and HR were significantly decreased, while MOAA/S increased in both groups (P < 0.05). At each time point after sedation, BIS and MOAA/S in the gourp D were higher than those in the group M (P < 0.05), the incidences of hypotension and bradycardia in the group D were lower than those in the group M (P < 0.05). The time from ICU admission to enablement of off-machine ventilation and off-machine ventilation period were shorter in the group D than in the group M (P < 0.05). Conclusions Continuous infusion of Dexmedetomidine 0.2 μg/(kg?h) or Midazolam 0.4 mg/(kg?h) facilitates the sedative effect in elderly patients with mechanical ventilation after cardiac surgery in ICU. Under the equivalent level of sedation, Dexmedetomidine could shorten the time for off-machine ventilation, and decrease the incidences of adverse reactions.