Regional Gas Trapping in Bronchoconstricted Asthmatics

描述(申请人提供)：哮喘是一种发病率迅速上升的疾病，仅在美国就已经影响了1700多万人。了解哮喘加重期间发生的潜在的机械和生理变化的机制是非常重要的。该项目的长期目标是扩大对这些机制的了解，为开发诊断、监测和管理哮喘的改进方法提供基础。支气管收缩是哮喘的基本特征，其在肺内的空间分布对哮喘的诊断和治疗具有广泛的意义。越来越多的实验工作表明，肺的异质性反应不能用单个呼吸道的独立行为总和来预测。对这一建议的中心假设是，这种反应是肺的综合反应的反映，包括呼吸道和实质之间的串联和并行相互作用。这项建议侧重于这一假说的三个关键方面：1)哮喘患者的平行异质性与气道树的综合反应之间的联系；2)深吸(DL‘s)在气道阻塞的发生和恢复中的区域性效应；以及3)用深吸(Dl’s)重新开放肺的呼吸缺陷区，以改善吸入气雾剂药物沉积和效果的串联和平行均匀度。这些研究将在健康人和哮喘患者中进行，并将通过正电子发射成像和高分辨率CT获得的对肺功能、结构和吸入气雾剂沉积的非侵入性地形评估与肺力学的全球测量和建模相结合。我们预计，这些详细的解剖和功能数据将为疾病的病理生理学提供新的见解，直接适用于患者护理，并将有助于推进气雾剂治疗领域。

DESCRIPTION (provided by applicant): Asthma is a disease of rapidly increasing incidence that already affects more than 17 million people in the United States alone. It is of major importance to understand the mechanisms responsible for underlying mechanical and physiological changes that occur during asthma exacerbations. The long-term objective of this project is to expand the understanding of these mechanisms to provide the foundations upon which to develop improved methods for diagnosing, monitoring and managing asthma. Bronchoconstriction is a cardinal feature of asthma, and its spatial distribution within the lungs has wide implications for diagnosis and therapy. An increasing amount of experimental work suggests that the heterogeneous response of the lung cannot be predicted by the summed independent behavior of individual airways. The central hypothesis to this proposal is that such response is a reflection of the integrated response of the lung including serial and parallel interactions amongst airways and parenchyma. This proposal focuses on three key aspects of this hypothesis: 1) the link between parallel heterogeneity in ventilation in asthma with the integrated response of the airway tree, 2) the regional effect of deep inhalations (Dl's) in the development of and recovery from airway obstruction, and 3) the reopening of ventilation defective regions of the lung with Dl's to improve the serial and parallel uniformity of inhaled aerosol drug deposition and effectiveness. The studies will be conducted in healthy persons and patients with asthma and combine non-invasive topographic assessments of lung function, structure and inhaled aerosol deposition, obtained with positron emission imaging and high resolution CT, with global measurements and modeling of lung mechanics. We expect that this detailed anatomical and functional data will provide new insights into the pathophysiology of the disease that will be directly applicable to patient care and will help advance the field of aerosol therapy.