临界关闭压在脑血流动力学评价中的应用

目的探讨检测脑血流动力学的快捷、实用的新方法，为临床检测奠定基础。方法利用经颅多普勒(TCD)检测大鼠大脑中动脉(MCA)的血流速度，同步记录有创血压，按照临界关闭压(CCP)的理论计算出脑血流自动调节的下限和微动脉阻力，与改变血压测定的结果进行比较。结果CCP法检测到的脑血流自动调节下限为70.88±24.05mmHg，与常用血压改变测定的结果数值接近，可以相互替代。肾血管性高血压大鼠(RHR)的脑血流自动调节下限和微动脉阻力的升高，与动脉血压的升高，特别是脉压差的增大密切相关。结论按照CCP理论测定脑血流自动调节下限和微动脉的阻力，可以准确、快捷地反映脑血流动力学的生理状态和病理改变。

Evaluating cerebral blood flow autoregulation by critical closing pressure.

Objective 　To establish a new practical method to assess the cerebral blood flow autoregulation. Methods　We assessed the flow velociey of middle cerebral artery with transcranial Doppler and recorded invasively the blood presure simultaneonsly. Then on the basis of critical closing pressure (CCP), the lower limit of cerebral blood flow autoregulation and the blood flow resistance of arterioles were calculated.The data compared with the results generated by routine method. Results　The lower limit of autoregulation working out by CCP was 70.88±24.05 mmHg, which was similar to the result measured by routine method. The lower limit of autoregulation and the arteriole resistance in RHR were significantly higher than those of normal controls, and highly relate to arterial blood pressure significantly, especially pulse pressure. Conclusions　The physiology and pathology of cerebral blood flow can be evaluated conveniently and accurately by assessment of the lower limit of autoregulation and arterioles resistance with CCP.