异丙酚对瓣膜置换病人脑氧代谢影响的临床研究

EFFECTS OF PROPOFOL ON CEREBRAL OXYGEN METABOLISM FOR HEART VALVE REPLACENMENT PATIENT

目的 观察瓣膜置换病人体外循环 (CPB)期间的脑氧代谢 (SjO2 ,ERO2 )的情况及异丙酚对脑氧代谢的影响 ,探讨异丙酚的脑保护作用。方法 将 32例择期瓣膜置换病人 ,随机分为观察组和对照组。观察组CPB开始用微量泵静注异丙酚 4mg/kg·h ,至CPB结束。其他麻醉药物的应用两组基本相同。于麻醉后CPB前 (A)、CPB开始 (B)、低温恒温期 (C)、复温至 33℃ (D)、CPB结束(E)和手术结束 (F) 6个时间点 ,,经桡动脉和颈内静脉球处采集血样 ,测定动脉、静脉血气。结果 两组病人于CPB开始后的降温期内SjO2 升高 ,ERO2 降低 ,组内差异明显 (P <0 .0 1) ;复温期至CPB结束 ,观察组的SjO2 和ERO2 较复温前无显著改变 (P >0 .0 5 ) ,对照组的SjO2 较复温前降低明显 (P <0 .0 5 ) ,ERO2 升高明显 (P <0 .0 5 ) ;两组比较 ,观察组的SjO2 显著高于对照组 (P <0 .0 5 ) ,ERO2 显著低于对照组 (P <0 .0 5 ) ;手术结束时 (F)两组的SjO2 和ERO2 均接近于A点的水平 (P >0 .0 5 )。结论 在CPB初期降温过程和复温过程中 ,反映脑氧代谢状况的SjO2 和ERO2有显著改变 ;异丙酚可明显减轻CPB复温过程中的SjO2 的降低和ERO2 的升高 ,改善脑氧供 /需平衡。

Objective To observe the information of cerebral oxygen metabolism(SjO 2:internal jugular venous oxyhemoglobin saturation;ERO 2:cerebral oxygen extraction rate) and to observe the effect of propofol on cerebral oxygen metabolism.Methods Thirty two heart valve replacement patients were randomly assigned into two group.observation group were infused Propofol 4mg.kg 1 .hcontinously with trace pump during CPB,while control group were not infused with propofol.Sample were collected at six time points,A: prior to CPB after anesthesia induction,B: CPB starting,C: period of the deepest stable temperature,D: 33℃ rewarming,E:CPB stoping,F: operation finished.Blood was simultaneously withdrawn via the line of radical artery and the internal jugular vein respectively.The arterial and venous blood gases were measured.Results During reducing the temperature of starting CPB,in SjO 2 two group in creased significantly(P<0.01),while ERO 2 decreasd significantly (P<0.01) .During the rewarming to stoping CPB(E),SjO 2 and ERO 2 in observation group were not changed significantly(P>0.05),while in the control group,SjO 2 were decreased significantly than that of hypothermia periods(P<0.05),ERO 2 were increased significantly than that of hypothermia period (P<0.05).There was a markedly difference between the two groups,SjO 2 in observation group were markedly higher than that in contral group(P<0.05),ERO 2 in observation group were markedly lower than that in control group(P<0.05).SjO 2 and ERO 2 in two group were almost equal in two time points F and A(P>0.05).Conclusion The information SjO 2 and ERO 2,which reflect cerebral oxygyen metabolism,change significantly during reducing temperature and rewarming CPB.Propofol can significantly relieve the decreasing of SjO 2 and increasing of ERO 2 in CPB rewarming process,thus improve the condition of cerebral oxygen supply/demand imbalance.