VIDEO IMAGING AND NEONATAL BRAIN OXYGENATION

对于新生儿来说，保持大脑良好的氧气供应是极其重要的 以避免不可逆转的功能损失。我们开发了新的 成像技术，以获得高分辨率(&lt；5um/像素)、定量、 二维图显示血管和毛细血管床中的氧分压 皮质，以及细胞内pH和细胞内钙离子 浓度分布在大脑皮层细胞表层。这些 在新生仔猪身上测量的代谢物图谱将使我们能够量化 大脑皮层的氧合和细胞生理学依赖于 PaCO_2、PaO_2、血pH和全身血压。“关键”氧气 大脑皮层毛细血管床的压力，即低于 观察到脑电、细胞内pH或细胞内钙离子的变化 浓度，将被确定。每种疾病的严重程度和持续时间 缺氧/代谢紊乱需要造成不可逆转的损害，如 由测量的参数未能恢复正常值来表示， 也将被确定。具体地说，我们将：a.量化 皮层氧分压和功能对PaCO2的依赖性。胡麻B. 量化氧气输送到大脑皮层的影响 全身血压。C.量化PaCO2和PaO2的相互作用 调节大脑皮层局部的微血管系统。D.确定 代谢性酸血症对皮质氧合和功能的影响。E. 评价微血管损伤在脑不可逆性损伤中的作用 功能。将开展合作研究，将上述各项联系起来 微透析法测定神经递质代谢参数。 这些措施将使我们能够严格评估 旨在优化氧气输送并减少不可逆性的治疗 对新生儿大脑的损害。

In the newborn it is extremely important to keep the brain well oxygenated in order to avoid irreversible loss of function. We have developed new imaging technology to obtain high resolution (< 5 um/pixel), quantitative, two dimensional maps oxygen pressure in the veins and capillary beds of the cortex, as well as of intracellular pH and intracellular Ca2+ concentrations in the surface layers of cell of the brain cortex. These metabolite maps, measured in newborn piglets, will allow us to quantitate the dependence of oxygenation and cellular physiology of the cortex on PaCO2, PaO2, blood pH and systemic blood pressure. the "critical" oxygen pressures in the capillary beds of the cortex i.e. those below which alterations are observed in EEG, intracellular pH or intracellular Ca2+ concentration, will be determined. The severity and duration of each hypoxia/metabolic perturbation require to cause irreversible damage, as indicated by failure of the measured parameters to recover normal values, will also be determined. Specifically we will: A. Quantitate the dependence of cortical oxygen pressure and function on PaCO2. B. Quantitate the dependence of delivery of oxygen to the cortex effect on systemic blood pressure. C. Quantitate the interactions of PaCO2 and PaO2 in regulating the local microvascular system of the cortex. D. Determine the effect of metabolic acidemia on cortical oxygenation and function. E. Evaluate the role of microvascular damage in irreversible damage to brain function. Collaborative studies will be carried out to correlate the above parameters with neurotransmitter metabolism as evaluated by microdialysis. These measures will permit critical evaluation of the efficacy of treatments designed to optimize oxygen delivery and to reduce irreversible damage to the brain of the newborn.