异丙酚和异氟烷在瓣膜置换术中对脑保护作用的比较

The Comparison between Isoflurane and Propofol with Effect on Cerebral Protection in Cardiac Valve Replacement Surgery

目的观察以异丙酚为主的全凭静脉麻醉与以异氟烷为主的静吸复合麻醉用于体外循环(extracorporeal circulation,ECC)下瓣膜置换术对脑氧供需平衡的影响,并通过测定脑损伤标志蛋白质S100β蛋白的浓度比较两种麻醉方法对脑的保护作用。方法择期ECC下瓣膜置换术30例,随机分为全凭静脉麻醉组与静吸复合麻醉组,分别在麻醉后、ECC开始10 min时、升主动脉开放前5 min、ECC结束30 min时抽取桡动脉血及颈内静脉球部血测血气并测定颈内静脉血浆S100β蛋白的浓度。结果两组均观察到在降温期颈静脉氧饱和度(SjvO2)明显增高,动脉-颈动脉氧含量差(D(a-jv)O2)和氧摄取率(O2ER)则明显降低,而在复温时两组(SjvO2)较ECC前降低,而D(a-jv)O2和O2ER则明显增加(P<0.01)。其中静脉麻醉组的变化幅度要远远低于静吸复合组(P<0.01)。ECC前所有患者的血浆S100β蛋白的水平均低于0.5μg/L。两组ECC开始后血浆S100β蛋白的水平迅速升高,ECC结束时达峰值水平,但静脉麻醉组较静吸复合麻醉组低(P<0.01)。结论两种麻醉方法均能满足ECC下瓣膜置换手术的需要,但根据本实验结果,全凭静脉麻醉比静吸复合麻醉更有利于ECC下瓣膜置换手术患者的脑保护。

OBJECTIVE To observe the effects of isoflurane and propofol on the changes of cerebral oxygen metabolism and blood concentration of S100 β protein in cardiac valve replacement surgery. METHODS Thirty patients scheduled for cardiac valve replacement surgery with extracorporeal circulation （ECC） were randomly assigned into two groups, isoflurane group and propofol group. The radial arterial and jugular venous bulb oxygen saturation were recorded at four time points after anaesthesia, ECC 10 min, before aortic opening 5 min and after ECC 30 min. The jugular venous blood was taken at the four time points to measure the blood concentration of S100 β protein. RESULTS The jugular venous bulb oxygen saturation in the two groups were both increased during cooling period and then decreased during warming period, but the change in isoflurane group is less than in the propofol group（ P 〈 0.05 ）. The blood concentrations of S100 β protein were both increased after ECC, but the concentrations protein in propofol group were lower than in isoflurane group （ P 〈 0.05）. CONCLUSION Propofol has better cerebral protection effects than isoflurane in cardiac valve replacement surgery with ECC.