脑血流自动调节监测及其围手术期应用研究进展

摘要

Cerebral blood flow autoregulation is physiologically protective mechanism to maintain the stability of cerebral blood flow.Once autoregulation is impaired, the cerebral blood flow fluctuates with blood pressure, leading to the risk of brain ischemia or cerebral hyperemia.Multiple research results indicate that cerebral blood flow can be monitored indirectly and continuously with transcranial Doppler, near infrared spectroscopy or ICP.The correlation coefficient calculated by the surrogate for cerebral blood flow and blood pressure is used to judge cerebral blood flow autoregulation.When the correlation coefficient is close to 1, cerebral blood flow will be passively fluctuated by blood pressure, indicating autoregulation is impaired.When the coefficient is less than 0, cerebral blood flow will not be changed with blood pressure, indicating autoregulaiton is intact.The status of autoregualtion is closely associated with mortality or poor neurological outcomes in patients with cardiac surgery underwent cardiopulmonary bypass, liver transplantation patients or patients with deep trendelenburg position for long time or beach chair position.Continuous monitoring of cerebral blood flow autoregulation can identify the lower or the upper limit of autoregulation, and provide information to individualize the perioperative management of blood pressure.%脑血流自动调节是维持脑血流量稳定的生理性保护机制。一旦失调脑血流量将随血压升降而被动涨落，机体可能面临脑充血或脑缺血的风险。采用相关分析法将反映脑血流量的间接参数与自发性波动的血压进行实时相关分析，可以实现脑血流自动调节的实时监测。脑血流自动调节的完好与否与心脏手术、肝移植手术及需要特殊体位的手术患者的中枢神经系统并发症密切相关。脑血流自动调节的持续监测可以为脑血流自动调节的血压上限或下限提供信息，有望为临床医生对围手术期患者进行合理的血压调控和脑功能保护提供可靠依据。