VENTILATION BY HIGH-FREQUENCY BODY-SURFACE OSCILLATION

提出了一种新的方法，以提供解释性支持和促进 用于患有呼吸功能不全的婴儿的粘液清除。 的 将婴儿的躯干和下半身放置在配备有 脖子上有一个洞，这样他的头就可以暴露在室内空气中， 专用流浆箱。 腔室压力围绕平均值快速振荡， 压力可以低于大气压。 负压应该扩张 他的气道;快速振荡将产生高频浅层 呼吸，使他能够进行气体交换，也可能增强 他的粘液清除率 这种方法避免了气管插管的必要性 插管，可以减少肺部漏气和其他形式的 气压伤，并预计产生较少的心血管干扰 比传统的机械呼吸机。 为了评估这一概念的可行性，并了解 不同动物对快速身体振荡的生理反应， 将在四组动物中检查多个参数，即， 正常和表面活性剂缺乏的成年兔以及正常和 缺乏表面活性剂的新生仔猪。 将有三个国家 在大多数实验中研究过：自主呼吸， 高频体表叠加自主呼吸 振荡和单独的高频体表振荡。 的 要检查的生理参数是：a）气体交换，包括 血气张力、生理死腔和可能的气体转运 B）心血管功能，包括心输出量、全身性 血管阻力、肺血管阻力等血流动力学参数 对快速胸膜内压变化的反应; c） 颅内压; d）呼吸力学，包括肺顺应性， 动态顺应性、肺和胸壁阻抗以及上气道 阻力; e）粘液产生和清除率;和f）体热损失， 包括对中度低温的心肺反应。 伴随着这一主题，使用低振幅的可能性 作为一种心脏辅助形式高频胸腔周围按压将 探索，物理模型和理论研究，旨在获得 还将获得关于身体热量损失的分析知识。

A new method is proposed to provide ventilatory support and to promote mucus clearance for infants suffering from respiratory insufficiency. The trunk and lower body of an infant is placed in an airtight chamber equipped with a neck-hole so that his head is exposed to either room air or a special head-box. The chamber pressure is oscillated rapidly about a mean pressure which may be subatmospheric. The negative pressure should distend his airways; the rapid oscillations will generate high-frequency shallow breaths, enabling him to engage in gas exchange and possibly also enhancing his mucus clearance. This method avoids the necessity of tracheal intubation, may reduce the risks of pulmonary air leaks and other forms of barotrauma, and is expected to produce less cardiovascular disturbances than the conventional mechanical ventilator. To assess the feasibility of this concept as well as to understand the physiological responses of different animals to rapid bodily oscillation, a number of parameters will be examined in four groups of animals, i.e., normal and surfactant-deficient adult rabbits as well as normal and surfactant-deficient newborn piglets. Three ventilatory states will be studied in most of the experiments proposed: spontaneous breathing, spontaneous breathing with superimposed high-frequency body-surface oscillation, and high-frequency body-surface oscillation alone. The physiological parameters to be examined are: a) gas exchange, including blood gas tensions, physiological dead space and possible gas transport mechanisms; b) cardiovascular function, including cardiac output, systemic vascular resistance, pulmonary vascular resistance and other hemodynamic responses to rapid intrapleural pressure variation; c) stability of intracranial pressure; d) respiratory mechanics, including lung compliance, dynamic compliance, lung and chest wall impedances and upper airway resistance; e) mucus production and clearance rates; and f) body heat loss, including the cardiopulmonary responses to moderate hypothermia. Adjunct to this main theme, the possibility of using low-amplitude high-frequency perithoracic compression as a form of cardiac assist will be explored, and a physical model and theoretical study aimed at gaining analytical knowledge about body heat loss will also be made.