LUNG VASCULAR EFFECTS OF HIGH FREQUENCY VENTILATION

这个项目的目标是调查高风险的影响 高频通气(HFV)对肺血管功能的影响。这个 工作假说是血管活性物质，二十烷类化合物和 心房利钠因子(ANF)在物质可以 对心输出量、肺和全身血管的影响 压力和水平衡。HFV的影响可能是 受通风条件的调节，包括存在 低氧和高碳酸血症。最初，兔子将是试验性的 动物。这些是最低等级的动物 美国希望获得关于肾综合征出血热病毒系统的有用数据。在身体和身体方面 器官的大小和重量，它们将接近人类婴儿。 后续数据将在绵羊身上收集，以更近距离地 模拟机械通风人体内的条件。出血热病毒是 在麻醉期间临床上很重要，当外科医生 当他需要一个不动的场地时，他就会为了争夺航道而竞争。 HFV在血液中二氧化碳被清除的地方也很重要 压力成本最低，如支气管胸膜瘘、肺瘘 间质性肺气肿或持续性肺动脉高压 新生儿。尚未有关于肾综合征出血热病毒影响的研究报道。 关于释放ANF的问题。此外，到目前为止报道的极少数研究 肾综合征出血热病毒对二十烷类化合物释放的影响 在低氧期间，都产生了相互矛盾的结果。生理学 本项目要记录的参数包括系统和 肺动脉压，肺楔压， 左房压、心率、心输出量、动脉血 气体，包括pH值、二十烷类化合物和ANF的浓度 血浆和淋巴中，呼吸道压力和体温。 心输出量将通过热稀释来确定。 技术。心脏插管也将提供一种测量 对肺动脉压和肺楔压的影响。 肺血管阻力将由心脏计算 心输出量和肺动脉及楔形或左心房 压力。将HFV的效果与传统的 机械通气对肺血管功能的影响。我们会 HFV对缺氧性肺血管收缩作用的实验研究 以及ANF等内源性调节剂的释放。我们会 急、慢性输注心钠素对肺影响的研究 血管和呼吸道功能以及缺氧性血管收缩。

The objective of this project is to investigate the effects of high frequency ventilation (HFV) on pulmonary vascular function. The working hypothesis is that vasoactive substances, eicosanoids and atrial natriuretic factor (ANF) are released during substances can influence cardiac output, pulmonary and systemic vascular pressures and water balance. The effects of HFV may be modulated by the conditions of ventilation, including the presence of hypoxia and hypercapnia. Initially rabbits will be experimental animals. These are the lowest order of animals which will allow us to obtain useful data on the HFV system. In terms of body and organ sizes and weights, they will approximate human infants. Subsequent data will be collected in sheep to more closely simulate conditions in the mechanically ventilated human. HFV is clinically important during anesthesia when the surgeon is competing for the airway or when he requires a motionless field. HFV is also important where blood CO2 is to be removed with the least pressure cost such as with bronchopleural fistula, pulmonary interstitial emphysema or persistent pulmonary hypertension in the newborn. No studies have been reported on the effect of HFV on the release of ANF. Also, the very few studies reported so far on the effect of HFV on the release of eicosanoids, particularly during hypoxia, have yielded conflicting results. Physiological parameters to be recorded in this project include systemic and pulmonary arterial blood pressures, pulmonary wedge pressure, left atrial pressure, heart rate, cardiac output, arterial blood gases, including pH, concentrations of eicosanoids and ANF in plasma and in lymph, airway pressure and body temperature. Cardiac output will be determined by the thermodilution technique. Cardiac catherization will also provide a measurement of pulmonary arterial pressure and pulmonary wedge pressure. Pulmonary vascular resistance will be calculated from cardiac output and the pulmonary arterial and wedge or left atrial pressures. The effect of HFV will be compared with conventional mechanical ventilation on pulmonary vascular function. We will test the effects of HFV on hypoxic pulmonary vasoconstriction and on release of endogenous modulators such as ANF. We will study the effects of acute and chronic infusion of ANF on lung vascular and airway function and on hypoxic vasoconstriction.