CONSEQUENCES OF PEEP AND HIGH FREQUENCY VENTILATION

这些研究是为了确定不同程度的积极影响 呼气末压力(PEEP)和高频呼吸机(HFV) 正常通透性和高通透性肺血管内液体交换 阿龙。研究将在完好无损的麻醉绵羊身上进行。 才有可能收集到纯净的肺淋巴。淋巴流量的测定 淋巴和血浆蛋白浓度与湿/无血肺干比 将被用来评估液体过滤和血管的可能变化 渗透性，因为它们可能或不可能由于PEEP或HFV在 正常肺和血管损伤肺。此外，总体和区域 用标记的微球研究肺血流将在 各种实验条件和不同的通风方式。这些 研究将与测量和间质压力相关 根据Parker等人的方法。并且可以提供生理上的 呼气末正压和肾综合征出血热病毒可能作用于 肺血管内液体平衡。肾综合征出血热病毒是一种临床上非常有前途的 一种可广泛应用于集约化医院的新型通风模式 护理环境。由于其生理基础尚不清楚，因此肺 正常通透性和高通透性的血流动力学和整体气体交换 狗的肺将使用大范围的闪烁进行 相机和标记的微球。在HFV实验中，平均气道 压力将保持在最小(203厘米H2O)，因为这是 HFV在窥视通风口上方。

These studies are to determine the effects of varying levels of positive end-expiratory pressure (PEEP) and high frequency ventilation (HFV) on pulmonary transvascular fluid exchange in the normal and high permeability lung. Studies will be made in the intact, anesthetized sheep in which it is possible to collect pure lung lymph. Determination of lymph flow of lymph and plasma protein concentration and wet-to-bloodless dry lung ration will be used to assess possible changes in fluid filtration and vascular permeability as they may or may not occur as a result of PEEP or HFV in the normal and vascular injured lung. In addition, the overall and regional pulmonary blood flow with labelled microspheres will be studied under the various experimental conditions and different modes of ventilation. These studies will be correlated with measurement and interstitial pressure according to the method of Parker et al. and may provide physiological bases for the mechanism by which PEEP and HFV may have their effects on pulmonary transvascular fluid balance. HFV is a clinically very promising new mode of ventilation that may find wide application in the intensive care setting. Since its physiological base is not known, pulmonary hemodynamics and overall gas exchange in the normal and high permeability lung of the dog will be performed utilizing a large field scintillation camera and labelled microspheres. With the HFV experiments the mean airway pressure will be kept minimal (203 cm H2O), as this is a major advantage of HFV over PEEP ventilation.