脑血流速度联合血液流变学检测对外伤性脑梗死的预测作用

目的通过观察重型颅脑外伤术后大脑中动脉平均血流速度（MCA Vm）和血液流变学诸指标的变化规律，探讨两者联合检测对外伤性脑梗死的预测价值。方法选取重型颅脑外伤术后患者104例和健康体检者40例，用脑血管多普勒（TCD）检测MCA Vm，同时测定全血低切黏度（LWBV）、全血高切黏度（HWBV）、血浆黏度（PV）和纤维蛋白原（Fi）含量，对数据进行相关统计分析。结果重型颅脑外伤组术后第1天，MCAVm、LWBV、HWBV、PV和Fi含量明显升高，第3天达到高峰，以后逐渐下降，术后第1、3、5、7、14天的MCA Vm均显著高于对照组（P〈0.01）。脑梗死者术后5个时间点MCA Vm和血液流变学指标均明显高于非脑梗死者（P〈0．05）。ROC曲线对预测重型颅脑外伤术后外伤性脑梗死有较高的灵敏度和特异度，血浆Fi含量尤为灵敏，TCD检测大脑MCA Vm联合血浆Fi含量测定预测外伤性脑梗死的灵敏度为97.8％，特异度为53.1％。结论脑血管痉挛和血液流变学异常是颅脑外伤继发性脑损伤的重要危险因素，参与外伤性脑梗死的病理生理过程，TCD检测MCA Vm联合血浆Fi含量测定可明显提高外伤性脑梗死预测的灵敏度。

Predictive value of combined mean blood velocity with hemorheological indexes for traumatic cerebral infarction

Objective To assess the predictive value of mean blood velocity of middle cerebral artery combined with hemorheological indexes for traumatic cerebral infarction. Methods One hundred and four patients with severe traumatic brain injury undergoing surgical procedures and 40 healthy controls were included in the study. The mean blood velocities of middle cerebral arteries were determined by transcranial Doppler （TCD） ultrasound examination; the hemorheological indexes （low shear and high shear viscosity of the whole blood, plasma viscosity） and plasma fibrinogen level were measured in all subjects. Results The mean blood velocities of middle cerebral arteries and low shear and high shear viscosity of the whole blood, plasma viscosity, and plasma fibrinogen levels in patients with severe traumatic brain injury increased immediately during 24 h after operation, peaked in 3 days, decreased gradually thereafter, and were substantially higher than those in healthy controls during the 14-day period （P〈0.001）. The mean blood velocities of middle cerebral arteries and hemorheological indexes in patients with traumatic cerebral infarction were significantly higher than those in patients without traumatic cerebral infarction （P〈0.05）. The mean blood velocity of middle cerebral artery combined with plasma fibrinogen level predicted occurrence of traumatic cerebral infarction with 97.8% sensitivity and 53.1% specificity. Conclusion Cerebral arterial vasospasm and abnormal alterations of hemorheology may play an important role in secondary brain injury after head trauma, and can be involved in pathophysiology of traumatic cerebral infarction. The mean blood velocity of middle cerebral artery combined with plasma fibrinogen level predicted occurrence of traumatic cerebral infarction with high sensitivity and moderate specificity.