七氟醚控制性降压对脑代谢的影响

Effects of sevoflurane induced hypotension on cerebral metabolism

目的 观察七氟醚控制性降压的效果及对脑氧供需平衡、脑能量代谢的影响 ,并与硝普钠 (SNP)降压进行对比。方法 择期手术病人 40例随机分为三组 :Ⅰ组七氟醚降压组 ,Ⅱ组七氟醚常压组和Ⅲ组SNP降压组。Ⅰ组增加七氟醚吸入浓度 ,Ⅲ组静滴SNP溶液 ,降至基础值的 5 0 %～6 0 %持续 40min ,连续监测MAP、HR、及ECG ,并同步采集桡动脉和颈内静脉血行血气分析 ,计算动-颈内静脉氧含量差 (Da jvO2 ) ;测定算出动 -颈内静脉血乳酸、SOD、MDA含量差 (Da jvL、Da jvSOD、Da jvMDA)。 结果 Ⅰ组降压后Da jvO2 呈降低趋势 ;而Ⅲ组Da jvO2 显著增加。三组各时点乳酸含量、Da jvL、Da jvSOD、Da jvMDA均无显著变化。 结论 七氟醚控制性降压脑组织氧供和灌注良好 ,脑内氧自由基代谢正常 ,能很好维持脑的能量代谢 。

Objective To evaluate the efficacy and the effects of sevoflurane induced hypotension on balance of cerebral oxygen supply and consumption and on cerebral energy metabolism. Methods Forty patients undergoing elective procedures were randomly divided into three groups. Group Ⅰ :sevoflurane induced hypotension ; group Ⅱ: sevoflurane maintained normal arterial tension ; group Ⅲ: nitroprusside induced hypotension . In groupⅠ and Ⅲ MAP was decreased to 50%-60% of baseline ,was kept for 40 min either by sevoflurane inhalation or by nitroprusside infusion. MAP ,HR,ECG were monitored continuously, and radial arterial blood samples and jugular blood samples were taken synchronously for measuring blood gas and blood lactate ,SOD and MAD levels. Results In group Ⅰ during induced hypotension Da jvO 2 showed reduction ,but in group Ⅲ Da jvO 2 increased significantly. There were no significant changes in blood lactate level and in the cerebral arteriovenous differences of MAD and SOD in three groups.Conclusions The sevoflurane induced hypotension has no adverse effect on cerebral oxygen balance and the cerebral perfusion . The cerebral energy metabolism is well maintained . Sevoflurane can safely applied to controlled hypotension during cerebral neurosystem.