颅高压时脑脊液脉动压与脑灌注压相互关系的实验研究

Relationship between the variation of cerebrospinal fluid pulse pressure and cerebral perfusion pressure during the process of increasing intracranial pressure

目的 研究颅高压时脑脊液脉动压与脑灌注压的相互变化关系。方法 14条狗安置硬膜外球囊并注液制成颅高压模型。通过改变球囊内液体量改变颅高压程度和颅内容积。通过压力传感器持续记录脑室内压力、腰椎管内压力及体动脉压。结果 随着颅内压的持续增高 ,脑灌注压逐渐下降 ,脑脊液脉动压相应增高。脑脊液脉动压与颅内压的变化趋势呈现正性线性关系 (r=0 732 2 ,P <0 0 5 ) ,而与脑灌注压的变化趋势呈现负性线性关系 (r=- 0 6 879,P <0 0 5 )。结论 在实验性颅高压中 ,脑脊液脉动压随着脑灌注压的下降而增大 ,两者间呈现负性线性关系。在脑血管自动调节机制受损的情况下 ,脑脊液脉动压的变化可能提供脑血流量改变的信息。

Objective To investigate the relationship between the variation of cerebrospinal fluid pulse pressure and that of intracranial perfusion pressure during the process of increasing intracranial pressure.Methods Fourteen dogs were installed epidurally with latex sacculus to establish models of increased intracranial pressure. The degree of intracranial pressure and volume could be altered by changing the volume of fluid in the sacculus. During the process, pressure transducers were arranged to monitor and record the systematic blood pressure and the variation of the pressure of cerebral ventricle and lumbar subarachnoid space.Results With the continual increasement of intracranial pressure, the cerebral perfusion pressure decreased, and the cerebrospinal fluid pulse pressure correspondingly increased. A positive linear relationship between the variation of intracranial pressure and that of cerebrospinal fluid pulse pressure and a negative linear relationship between the variation of cerebral perfusion pressure and that of cerebrospinal fluid pulse pressure were found.Conclusion During the experimental process of increased intracranial pressure, with the decrease of cerebral perfusion pressure , the cerebrospinal fluid pulse pressure increases. The relationship of variations between them shows a negative linear one. It seems that in the circumstances when the autoregulation of cerebral vessel is injured, the variations of cerebrospinal fluid pulse pressure may produce some useful information as to the changes of intracranial blood flow.