Koons A H, Wurtzel D, Metcalf J M, Fellus J, Vannucci R, Hiatt M, Hegyi T
Department of Pediatrics UMDNJ-Robert Wood Johnson Medical School, St Peter's Medical Center, New Brunswick 08903.
Biol Neonate. 1993;63(2):120-8. doi: 10.1159/000243920.
Current methods of cerebral blood flow (CBF) determination provide only discrete, episodic data and are limited in assessing dynamic changes in cerebral circulation. We adapted a venous outflow technique employing cannulation of the superior sagittal sinus in newborn puppies to measure changes in CBF rapidly and sequentially during ventilatory maneuvers. CBF velocity (CBFV) was measured simultaneously with Doppler ultrasound of the anterior cerebral artery. Relationships between flow and velocity were determined during hypocarbia, hypercarbia, hypoxia and asphyxia. During hyperventilation, CBF decreased by a mean of 14%, and CBFV by 13%, whereas maximal CO2 inhalation increased CBF by 59% and CBFV by 110%. Although CBFV exhibited the same directional changes as shown by the area under the velocity curve, the magnitude of change was not proportional to flow. CBFV indicated trends in the direction of changes in flow in individual animals, but did not correlate with flow between animals. A fluctuating unstable pattern of CBFV, previously associated with neonatal intracranial hemorrhage, was demonstrated with hyperventilation and hypocarbia. During asphyxia, CBFV ceased 2-5 min prior to CBF, presumably reflecting continued brain perfusion from vessels other than anterior cerebral artery.
目前测定脑血流量（CBF）的方法仅能提供离散的、间歇性的数据，在评估脑循环的动态变化方面存在局限性。我们采用了一种静脉流出技术，通过对新生幼犬的上矢状窦进行插管，以在通气操作期间快速且连续地测量CBF的变化。同时使用大脑前动脉的多普勒超声测量CBF速度（CBFV）。在低碳酸血症、高碳酸血症、低氧血症和窒息期间确定流量与速度之间的关系。在过度通气期间，CBF平均下降14%，CBFV下降13%，而最大程度吸入二氧化碳使CBF增加59%，CBFV增加110%。尽管CBFV呈现出与速度曲线下面积所示相同的方向变化，但变化幅度与流量不成比例。CBFV表明了个体动物中流量变化的方向趋势，但与不同动物之间的流量无关。过度通气和低碳酸血症显示出一种先前与新生儿颅内出血相关的CBFV波动不稳定模式。在窒息期间，CBFV在CBF停止前2 - 5分钟停止，这可能反映了除大脑前动脉以外的血管对大脑的持续灌注。
