摘要
目的探讨测定脑血流自动调节下限(LLCA)的新方法,为LLCA的广泛临床测定奠定基础。方法同步监测正常健康志愿者正常呼吸、屏气和过度换气时的大脑中动脉血流、桡动脉血压和呼气终末呼出气体CO2分压(ETco2),然后离线计算临界关闭压(CCP)和LLCA。结果正常呼吸情况下LLCA为(58.42±10.40)mmHg,屏气时LLCA明显上升(P<0.05),过度换气时明显下降(P<0.05),且都和正常呼吸时的结果高度相关(r=0.6740、0.6429,P<0.05)。与正常呼吸相比,屏气和过度换气时LLCA测定差异的95%CI分别为(8.28￣13.68)mmHg和(-16.56￣-12.20)mmHg。屏气和过度换气时LLCA的变化率与CCP的变化率均呈负相关(r=-0.6105、-0.5551,P<0.05)。结论利用CCP可准确无创地测定人类LLCA。
Objective To set up a new way to measure the lower limit of cerebral autoregulation (LLCA) by critical closing pressure (CCP) so as to lay the foundation for the wide clinical application of LLCA. Methods The blood flow of middle cerebral artery,radial blood pressure and end-tidal CO2 (ETco2) were simultaneously monitored on healthy subjects among normocapnia,hyper-and hypocapnia respectively. The LLCA was determined by CCP. Results The LLCA of healthy subjects was (58.42±10.40) mm Hg at normocapnia. It increased at hypercapnia and decreased at hypocapnia significantly (P<005),and correlating positively with that at normocapnia (r=0.6740,0.6429,P<0.05). 95% CI of difference were (8.28~13.68) mm Hg between hypercapnia and normocapnia and (-16.56^-12.20) mm Hg between hypocapnia and normocapnia. The shifting rates of LLCA correlated inversely to the rates of CCP at both hypercapnia and hypocapnia (r=-0.6405,-0.5551,P<0.05). Conclusion The lower limit of cerebral autoregulation can be determined by CCP non-invasively and exactly.
出处
《中华神经医学杂志》
CAS
CSCD
2005年第6期592-595,共4页
Chinese Journal of Neuromedicine
基金
广州医学院博士启动基金(03-Q-01)
