无创测定脑循环阻力血管平滑肌舒缩功能的临床研究  

Noninvasive estimating vasomotor function of cerebral resistance vessels in human

作　　者：朱良付[1] 黄如训[2] 盛文利[2] 陈颖贤[2] 曾进胜[2] 

机构地区：[1]河南省人民医院神经内科,郑州450003 [2]中山大学附属第一医院神经内科

出　　处：《中华超声影像学杂志》2007年第10期860-863,共4页Chinese Journal of Ultrasonography

摘　　要：目的探讨无创测定脑循环阻力血管平滑肌舒缩功能的方法。方法应用经颅超声多普勒仪、无创血压监测仪持续记录16例健康志愿者正常呼吸、低碳酸血症和高碳酸血症时的大脑中动脉血流流速和桡动脉血压,用潮气末二氧化碳监测仪持续监测呼出气体的二氧化碳分压。低碳酸血症由过度换气获得,高碳酸血症通过吸入混合气体（5%CO2、21%O2和74%N2）获得。用傅立叶变换法分别测得三个阶段的临界关闭压（CCP）和有效脑灌注压（CPP）。结果低碳酸血症阶段大脑中动脉的平均流速较正常呼吸时明显下降,高碳酸血症阶段平均流速则较正常呼吸时明显增快,三个阶段的平均流速比较差异均有统计学意义（P=0.000）。平均动脉压（MAP）在低碳酸血症阶段有轻度下降,在高碳酸血症阶段MAP则有轻度上升,两者比较差异有统计学意义（P=0.030）,但两者与正常呼吸时的MAP比较差异均无统计学意义（P=0.127,P=0.241）。在低碳酸血症、正常呼吸、高碳酸血症三个阶段过程中,傅立叶变换法无创测定的CCP逐级降低,而有效CPP逐级升高,呈阶梯样变化。三个阶段的CCP和有效CPP比较差异均有统计学意义（P=0.000,P=0.000）。结论傅立叶变换法可用于无创测定脑循环阻力血管的平滑肌舒缩功能。　Objective To noninvasively estimate vasomotor function of cerebral resistance vessels in human.Methods Sixteen healthy volunteers were involved in the study.During the courses of hypocapnia,baseline and hypercapnia,transcranial Doppler velocities of middle cerebral artery and noinvasive blood pressure in radial artery were continuous recorded in subjects.End-tidal CO2 was also measured by a monitor.Hypocapnia was induced by voluntary hyperventilation,and hypercapnia was gained by conducting subjects breath a gas mixture of 5% CO2,21% O2,74% nitrogen.Critical closing pressure（CCP）and effective cerebral perfusion pressure（CPP）were calculated by Fourier transform method in three phrases,respectively.Results The velocities of middle cerebral artery decreased significantly during hypocapnia,and increased obviously during hypercapnia,there were significant changes among hypocapnia,hypercapnia and basline（P=0.000）.Hypocapnia caused a small fall in mean arterial pressure（MAP）,and hypocapnia had the opposite effect,although MAPs were significant difference in hypocapnia and hypercapnia（P=0.030）,both of them had not significant differences according with baseline（P=0.127,P=0.241）.Varying PCO2 produced significant changes in CCP and CPP.Hypercapnia decreased CCP and with a corresponding increased in CPP gradually,hypocapnia had the opposite effect.The changes in CCP and CPP induced by changes PCO2 were significant（P=0.000,P=0.000）.Conclusions Fourier transform method may be used to noninvasively estimate the vasomotor function of cerebral resistance vessels in human.

关 键 词：超声检查 多普勒 经颅 血管阻力 血压 脑血管循环 

分 类 号：R686[医药卫生—骨科学]