中度急性等容血液稀释对脑缺血状态下的脑保护作用(英文)  

Effects of acute normovolemic hemodilution in protecting brain after ischemia

作　　者：梅弘勋[1] 王恩真[1] 翟晶[2] 张辉[2] 

机构地区：[1]首都医科大学附属北京天坛医院麻醉科,北京市100050 [2]北京市神经外科研究所,北京市100050

出　　处：《中国临床康复》2004年第7期1353-1355,共3页Chinese Journal of Clinical Rehabilitation

摘　　要：背景:血液稀释是血液保护的重要措施,目前已广泛应用于临床。有研究报道血液稀释可降低血液黏度、增加脑血流,具有脑保护作用。但同时也降低血氧含量,使这一保护作用受到限制。目的:探讨中度急性等容血液稀释(acutenormovolemichemodilution,ANH)对大鼠局部脑缺血模型的脑血流和脑梗死面积的影响。设计:完全随机对照实验研究。地点和材料:本研究的地点在北京市神经外科研究所,材料为健康成年雄性Wistar大鼠16只,体质量300～350g,为中国医学科学院动物中心提供的二级动物。干预:16只Wistar大鼠单纯随机分为对照组(n=8)和ANH组(n=8),其中使ANH组血细胞比容(hematocrit,HCT)降至30.7%,两组分别阻塞左侧大脑中动脉。于缺血前和缺血120min内,用激光多普勒血流仪连续测定缺血周边皮层的局部脑血流(regionalcerebralbloodflow,rCBF)变化,以上部分由作者本人实施。缺血后24h,由不知道分组情况的人员测定脑梗死面积。主要观察指标:两组动物生理指标的比较及血液稀释后的变化,两组脑缺血前后rCBF的变化,TTC染色后两组脑梗死面积。结果:ANH组在ANH后,HCT从47.28%降至30.74%,动脉血氧含量(CaO2)从(8.90±0.57)mmol/L降至(5.91±0.74)mmol/L,与ANH前和对照组比较,差异有非常显著性意义(P<0.01)。在脑缺血后,两组缺血?BACKGROUND:Hemodilution is used widely in clinic as a method of blood conservation.It has been reported that hemodilution may ameliorate ischemia induced brain injury because it increases cerebral blood flow.However,it reduces arterial oxygen content as well.So hemodilution has limited success as a treatment of cerebral ischemia.OBJECTIVE:To assess the effects of moderate acute normovolemic hemodilution(ANH) on regional cerebral blood flow(rCBF) and cerebral infarct size in a rat model of focal cerebral ischemia. DESIGN:Completely randomized,controlled experiment.SETTING and PARTICIPANTS:Beijing Neurosurgical Institute.Sixteen male Wistar rats weighing 300-350 g were used.INTERVENTIONS:Sixteen Wistar rats were randomly assigned into two groups: control group(n=8) and ANH group(n=8).The hematocrit(HCT) of the animals in ANH group was reduced to about 30.7%.The left middle cerebral artery(MCA) was exposed transcranially in both groups.The animals underwent permanent occlusion of the left middle cerebral artery(MCAO) with microbipolar forceps.Cortical rCBF was monitored in both groups before and during the initial 2-hour MCAO with laser Doppler flowmetry(LDF).The infarct size of each brain was determined at 24 hours after MCAO by an experimenter who did not know the grouping.MAIN OUTCOME MEASURES:General physiological data collected in both groups.Changes of rCBF during the initial 2-hour MCAO in ANH group and cerebral infarct size at 24 hours after MCAO were assessed in both groups.RESULTS: In ANH group, hemodilution reduced HCT from 47.28%to 30.74%,and CaO2 from(8.90±0.57) mmol/L to(5.91±0.74) mmol/L(P< 0.01).rCBF reduced to 55.77%of baseline value in the ANH group and 28.5%in the control group during the 2-hour MCAO.There was a significant difference between the two groups(P< 0.01).The total area of infarction was 40.01%in the ANH group and 51.19%in the control group.There was a significant difference between the two groups(P< 0.05).CONCLUSION:Moderate ANH increases cortical rCBF and decreases brain infarct siz

关 键 词：中度急性等容血液稀释 脑缺血 脑保护 大鼠 动物模型 脑梗死 

分 类 号：R743.31[医药卫生—神经病学与精神病学] R457[医药卫生—临床医学]