右美托咪定对高龄髋关节置换术患者脑氧代谢和血流动力学的影响

Effects of Dexmedetomidine on Cerebral Oxygen Metabolism and Hemodynamics for Elderly Patients with Hip Replacement

目的探讨右美托咪定在高龄髋关节置换术患者围术期脑氧代谢和血流动力学的影响。方法选取髋关节置换术高龄患者48例,采用随机数字表法随机分为两组:右美托咪定组和对照组,每组各24例,右美托咪定组麻醉前静脉微量泵泵入右美托咪定1μg/m L,10 min后以0.4μg/(kg·h)持续泵入至手术主要操作结束,对照组为空白对照组,分别在全麻诱导前(T0)、手术开始后30 min(T1)和手术结束时(T2)等3个时点采集颈内静脉血和桡动脉血5m L进行血气分析,记录患者的动脉与颈内静脉球血氧饱和度(SaO_2、SjvO2)、氧分压(PaO_2、PjvO2),计算各时点动脉血氧含量(CaO_2)、颈静脉球部血氧饱和度(SjvO_2)、颈内静脉血氧含量(CjvO_2)、动-静脉血氧含量(CajvO_2)及脑氧摄取率(CERO2),记录3个时点的心率(HR)、平均动脉压(MAP)值。结果 T1时点SjvO_2和CjvO_2右美托咪定组明显高于对照组(P<0.05)。与T0时点比较,对照组T2时点、右美托咪定组T1、T2 Ca-jvO_2均明显降低(P<0.05),组间比较,T1、T2时点右美托咪定组CjvO_2均明显低于对照组(P<0.05)。T1、T2时点右美托咪定组CERO2均明显低于对照组(P<0.05),T1、T2时点右美托咪定组HR和MAP均明显高于对照组(P<0.05)。结论对髋关节置换术高龄患者,麻醉前静脉微量泵泵入右美托咪定,可保持患者血流动力学的稳定,减少脑氧消耗,可以有效的保护脑组织。

Objective To study the effects of Dexmedetomidine on cerebral oxygen metabolism and hemodynamics for elderly patients with hip replacement.Methods 48 elderly patients with hip replacement were randomly divided into Dexmedetomidine group and Control group,24 cases in each group.The two groups received tracheal intubation anesthesia.The Dexmedetomidine group was pumped Dexmedetomidine 1 μg /m L before anesthesia via intravenous micro pump and 0.4 μg /（ kg·h） until the end of the main operation after 10 minutes. The internal jugular venous blood and radial artery blood（ 5 m L） in the Control group were collected for blood gas analysis before induction of anesthesia（ T0）,30 min after operation（ T1） and at the end of operation（ T2）. The patient ＇s arterial and jugular venous oxygen saturation（ SaO_2,SjvO_2）,the oxygen partial pressure（ PaO_2,PjvO_2） were recorded. The arterial oxygen content（ CaO_2）,jugular bulb oxygen saturation（ SjvO_2）,jugular venous oxygen content（ CjvO_2）,arteriovenous oxygen content（ Ca-jvO_2） and cerebral oxygen uptake rate（ CERO2） were calculated at the three points.The heart rate（ HR） and mean arterial pressure（ the value of MAP） at the three points were recorded.Results At T1,the SjvO_2 and CjvO_2 of the Dexmedetomidine group were significantly higher than those of the Control group（ P〈0. 05）. Compared with T0,the Ca- jvO_2 in the Control group at T2 and in the Dexmedetomidine group at T1 and T2 were significantly decreased（ P〈0. 05）. The CjvO_2 of the Dexmedetomidine group at T1 and T2 were significantly lower than that of the Control group（ P〈0.05）.The CERO2 in the Dexmedetomidine group at T1 and T2 were significantly lower than that of the Control group（ P〈0.05）.The HR and MAP of the Dexmedetomidine group at T1 and T2 were significantly higher than those of the Control group（ P〈0.05）. Conclusion The elderly patients with hip replacement for Dexmedetomidin via intravenous micro pump before anesthesia can maintain hemodynamic stability,reduce cerebral oxygen consumption and effectively protect the brain tissues.