经颅多普勒检测21天头低位卧床期间脑底动脉血流动力学的变化  

Changes of human cerebral bottom artery hemodynamics measured by transcranial Doppler during 21 days head-down tilt(-6°) bed-rest

作　　者：王忠波 姚永杰[2] 吴兴裕 王新增 刘中昌 蒋昌林[3] 姜世忠[3] 

机构地区：[1]空军临潼疗养院,陕西临潼710600 [2]第四军医大学航空航天医学系 [3]航天医学工程研究所,北京100094

出　　处：《中华航空航天医学杂志》2000年第3期166-169,共4页Chinese Journal of Aerospace Medicine

摘　　要：目的　观察 2 1d头低位卧床期间脑底动脉血流动力学的变化。　方法　 6名健康男性志愿者 ,年龄 ( 2 4.8± 6 .1)岁 ,进行了 2 1d头低位 ( HDT- 6°)卧床试验。HDT前、HDT第 10 d及卧床结束时进行了 3次立位耐力检查。HDT前 (坐位 )、HDT开始时 ( D0 )、第 1、3、7、10、2 1d用经颅超声多普勒 ( TCD)测量了双侧大脑前、中、后动脉的血流动力学指标。　结果　卧床第 10 d和卧床结束时 ,受试者立位耐力比卧床前降低 ( P<0 .0 5 )。卧床期间 ,受试者右侧大脑中动脉的收缩期峰值血流速度vs 和平均血流速度 vm 较卧床前 ( pre- HDT)及卧床开始时降低 ,左侧大脑中动脉 vs在卧床开始时较卧床前增加 ,卧床第 3d又较开始时降低。在卧床前 ,大脑中动脉右左两侧流速差 BVD和右左两侧非对称指数 AI的均数分别为 7.0 cm/ s和 13.74% ,在卧床期间 BVD和 AI均数降为负值 ,较卧床前时降低 ( P<0 .0 5或 P<0 .0 1)。大脑中动脉的其余指标 (含脉动指数和阻力指数等 )、大脑前和后动脉的各指标变化不显著。　结论　 2 1d头低位卧床使立位耐力、双侧大脑中动脉的 vs 和右侧大脑中动脉的 vm 降低 ;HDT卧床期间 ,大脑中动脉血流速度降低和不对称变化 ,可能与立位耐力降低有关。Objective To investigate the changes of human cerebral bottom artery hemodynamics during 21 d -6° head-down tilt bed rest(HDT). Methods Subjects were 6 healthy male, aged (24.8±6.1). The systolic blood velocity(v s), diastolic blood velocity(v d),mean blood velocity (v m), pulsatility index(PI), resistance index(RI) and other indexes of middle cerebral arteries(MCA), anterior cerebral artery (ACA) and posterior cerebral artery (PCA) were measured by transcranial Doppler before HDT and on day 0, 1, 3, 7, 10, 21 of HDT. Head up tilt (HUT) +75° 20 min orthostatic tolerance test was done on day 1, 10, and 21 of HDT. Results During orthostatic tolerance test on day 10 and 21 of HDT, the average standing time was significantly shorter than that of the pre HDT (P<0.05). During HDT, the v s and v m of right MCA reduced significantly as compared with those of preHDT and those of day 0 (P<0.05 or P<0.01). Left MCA v s on day 0 was significantly higher than that of prHDT (P<0.05), but it became significantly lower than that of perHDT on d3 of HDT (P<0.01). Both MCA bilateral velocity difference (right v mleft v m) of the d 3, d 10, d 21 of HDT, and MCA interhemispheric asymmetry index of the d 10, d 21 of HDT were significant lower as compared with those of pre HDT P<0.05 or P<0.01). Conclusions The 21d HDT bedrest may result in lowering of orthostatic tolerance, the lowered v s of bilateral MCA and the interhemispheric asymmetry change of MCA during HDT may be responsible, in part, for the lowering of orthostatic tolerance.

关 键 词：模拟失重 脑底动脉 血液动力学 超声波诊断 

分 类 号：R85[医药卫生—航空、航天与航海医学]