REGIONAL MECHANICS OF THE DIAPHRAGM

隔膜的区域力学

• 批准号: 3350353
• 负责人: ROBERT LEE JOHNSON
• 金额: $ 15.06万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-12-01 至 1991-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3350353
• 关键词: cineradiography; computer graphics /printing; diaphragm; dogs; electrodes; fatigue; mathematical model; mechanical pressure; model design /development; muscle contraction; muscle tension; online computer; pulmonary respiration; respiratory airway volume; respiratory gas; respiratory hypoxia; respiratory insufficiency /failure; respiratory muscles; ribs; tendons

Specific aims are (1) to develop techniques to measure regional elastic and contractile behavior of the diaphragm in vivo in dogs using biplane cineradiography; and (2) using these techniques, to study changes in regional function of the diaphragm in response to local impairment of blood flow or local perfusion with anemic, hypoxic, or acidotic blood without causing overall diaphragmatic failure or systemic changes in arterial blood gases or pressures. Our hypothesis is that regional elastic behavior, contractile function, directions of regional length, curvature and area changes, and regional mechanical work can be studied in the diaphragms of intact animals using high speed biplane cineradiograhy to follow the motion of surgically implanted radiopaque markers. The methods of continuum mechanics will be used to analyze the data and to address the following questions: 1. What are the regional and overall changes in diaphragmatic surface area, radii of curvature and major directions of length change as transdiaphragmatic pressure is varied by passive changes in lung volume or during active contraction of the diaphragm? 2. Does the diaphragm contract and relax homogeneously and, if not, are inhomogeneities due to local differences in mechanical properties of the muscle or differences in orientation and curvature? 3. When regional perfusion of the diaphragm is impaired what is the relationship between local reduction in blood flow and work that can be sustained by that region? 4. What maximal level of work can a region of the diaphragm sustain without regional contractile function being affected when being locally perfused with hypoxic, anemic or acidotic blood at constant perfusion pressure or at constant flow? These studies should enhance our knowledge of the geometry and contractile function of the diaphragm in vivo and provide quantitative description of some important causes of diaphragmatic fatigue.

具体目的是（1）开发技术以测量区域弹性和 使用双翼飞机在狗体内膜片的收缩行为 灰色摄影； （2）使用这些技术研究 隔膜的区域功能响应局部血液损害 流量或局部灌注，贫血，低氧或酸性血液没有 导致整体隔膜衰竭或动脉血液的全身变化 气体或压力。 我们的假设是区域弹性行为，收缩功能， 区域长度，曲率和区域变化的方向以及区域 可以在完整动物的隔膜中研究机械工作 高速双翼飞机cineradiograhy遵循外科手术的运动 植入放射线标记。 连续机械的方法将是 用于分析数据并解决以下问题： 1。隔膜表面积的区域和总体变化是什么？ 曲率的半径和长度的主要方向变化为 跨倍压力因肺体积的被动变化或 在隔膜积极收缩期间？ 2。隔膜是否合同并同质放松，如果没有，则是 由于局部机械性能的局部差异而导致的不均匀性 肌肉或方向和曲率的差异？ 3。当隔膜的区域灌注受损时 局部减少血流与可以是的工作之间的关系 由那个地区维持？ 4. diaphragm的最大工作水平无需 当地灌注时，区域收缩功能受到影响 在恒定灌注压力下或在 恒流？ 这些研究应增强我们对几何和收缩的了解 diaphragm在体内的功能，并提供定量描述 diaphragm疲劳的一些重要原因。