异丙酚对体外循环冠状动脉旁路移植术中病人脑氧代谢及术后精神神经功能改变的影响

EFFECTS OF PROPOFOL ON CEREBRAL OXYGEN METABOLISM DURING CORONARY ARTERY BYPASS GRAFT UNDER CARDIOPULMONARY BYPASS

目的观察异丙酚对中低温体外循环（CPB）冠状动脉旁路移植术（CABG）中脑氧代谢的影响,分析脑氧代谢与术后脑损伤和精神神经功能改变的关系。方法择期CPB下行CABG病人80例,随机分为异丙酚组（P组）和异氟烷组（Ⅰ组）。两组常规麻醉诱导,麻醉诱导后即刻P组麻醉维持采用靶控输注异丙酚1-2μg/mL,持续静脉输注瑞芬太尼0.2-0.4μg/（kg.min）,Ⅰ组麻醉维持采用持续静脉输注瑞芬太尼0.2-0.4μg/（kg.min）和吸入异氟烷。两组术中间断静脉注射哌库溴铵,Ⅰ组在CPB中间断静脉注射咪唑安定。分别于麻醉前（T1）、麻醉诱导后30 min（T2）、降温结束后5 min（T3）、复温结束后5 min（T4）、CPB结束时（T5）从桡动脉、右颈内静脉球部采血进行血气分析及葡萄糖与乳酸（ADVL）测定,并计算脑血流量/脑氧耗比值（CBF/CMRO2）、脑氧耗/脑糖耗比值（CMRO2/CMRGlu）;术后采用标准神经功能和MMSE检查,将病人分为存在精神神经系统并发症（POMD）和无精神神经系统并发症（C）两组,并分别对以上指标进行统计学处理。结果P组POMD发生率低于Ⅰ组（χ2=13.7,P〈0.05）,颈静脉血氧饱和度（SjvO2）在T4点Ⅰ组明显低于P组（t=-2.46,P〈0.05）。T4点C组SjvO2、PjO2高于POMD组（t=2.16、6.07,P〈0.01）。T4点CBF/CMRO2比值POMD组显著低于C组（t=4.01,P〈0.001）。T3、T4、T5点POMD组CMRO2/CMRGlu比值明显低于C组（t=2.56-4.95,P〈0.05）。T4点POMD组ADVL高于C组（t=3.32,P〈0.05）。结论CPB下CABG术后精神神经并发症与CPB期间脑氧代谢失衡有关。异丙酚可以提高中枢氧合状态,减轻术后精神神经功能的改变。

Objective To observe the effects of propofol on changes of cerebral oxygen metabolism during coronary artery bypass graft （CABG） under moderate hypothermia cardiopulmonary bypass （CPB） and evaluate the relationship between indexes of cerebral oxygen metabolism and postoperative cerebral injury and mental function. Methods Eighty patients undergoing selective CABG under CPB were evenly divided, at random, into two groups; propofol group （group P） and ISO group （group I ）. Blood samples were taken from right internal jugular vein bulb and radial artery for determination of blood gas, glucose and lactic acid at different time points： before anesthesia （T1）, immediately after anesthesia induction （T2）, hypothermia over （T3）, rewarming over （T4）, at the end of bypass （T5）. Cerebral blood flow/cerebral metabolic rate of O2 （CBF/CMRO2）, cerebral metabolic rate of O2/cerebral metabolic rate of glucose （CMRO2/CMRGIu） and advent volume of lactification （ADVL） were calculated. After operation, patients were divided into postoperative mental disorders （POMD） group and non-POMD group （C） according to standard neurological function examination and mental measuring scale （MMSE）. All the above indexes were compared between the two groups. Results Incidence of POMD in group P was significantly lower than in group I （x^2 = 13.7,P〈0. 05）. SjvO2 of group I was significantly lower than that in group P at T4 （t=-2.46,P%0.05）, while SjvO2 and PjO2 of group C were significantly higher than that of group POMD （t = 2. 16,6.07;P〈 0. 05）, CBF/CMRO2 of group C was significant higher than that of group POMD 0=4.01 ,P〈00. 001）. CMRO2/CMRGlu of group POMD was significantly lower than that of group C at T3, T4, and T5 （t=2.56-4.95,P〈0.05）. ADVL of group POMD was higher than group C at T4 （t=3.32,P〈0.05）. Conclusion Postoperative mental and neurological complications with CABG under CPB are related with disequilibrium of cerebral oxygen metabolism during CPB. Propofol provides certain cerebral protection and increases central oxygenation, thus lowers the incidence of postoperative POMDo