Growth of Airways and Lung Parenchyma in Normal Infants

正常婴儿气道和肺实质的生长

• 批准号: 7218682
• 负责人: Robert S. Tepper
• 金额: $ 40.35万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-01 至 2010-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7218682
• 关键词: Adult; Age; Age-Years; Alveolar; Alveolus; Animals; Area; Arts; Autopsy; Birth; Borderline Personality Disorder; Bronchopulmonary Dysplasia; Cell Proliferation; Childhood; Chronic; Clinical; Clinical Trials; Computer Simulation; Conflict (Psychology); Continuous Positive Airway Pressure; Data; Delivery Rooms; Development; Diffuse; Diffusion; Early treatment; Effectiveness; Enrollment; Environmental air flow; Excision; Ferrets; Functional disorder; Gases; Growth; Growth and Development function; Heterogeneity; Human; Image; Infant; Institution; Intervention; Knowledge; Laboratories; Life; Living Wills; Lung; Lung diseases; Maintenance; Measurement; Measures; Mechanical ventilation; Mechanics; Methodology; Morphologic artifacts; Motion; National Institute of Child Health and Human Development; Neonatal; Noble Gases; Numbers; Oryctolagus cuniculus; Outcome; Pattern; Peripheral; Physiological; Pregnancy; Premature Birth; Premature Infant; Property; Pulmonary Diffusing Capacity; Range; Research; Research Personnel; Resolution; Respiratory distress; Respiratory physiology; Role; Staging; Structure; Structure of parenchyma of lung; Surface; Techniques; Therapeutic; Thick; Time; Tissues; Toddler; Uncertainty; Vital capacity; Week; X-Ray Computed Tomography; age effect; age group; airway obstruction; density; design; experience; improved; in vivo; infancy; lung development; lung injury; lung volume; premature lungs; programs; prophylactic; rapid growth; respiratory; size; surfactant; three dimensional structure; two-dimensional

DESCRIPTION (provided by applicant): This proposal will apply state-of-the-art techniques to assess normal growth and development of the lung parenchyma in infants and toddlers, an important and difficult age group to evaluate. Understanding lung growth early in life is critical for designing therapeutic strategies to promote lung growth in infants with lung disease. We will also evaluate the chronic pulmonary sequelae related to premature birth, as well as compare the effects upon lung structure and function of two different strategies for ventilatory support of very premature infants. Our laboratory developed the methodology to assess forced expiratory maneuvers in infants, and we have adapted this technique to measure single-breath diffusing capacity in infants, as an in vivo assessment of surface area for gas exchange. In addition, a technique to obtain high resolution CT images in infants at elevated lung volumes without artifacts from respiratory motion, we will obtain in vivo quantitative measurements of the lung parenchymal tissue density, as well as airway size and wall thickness. Ventilation inhomogeneity within the lung will also be assessed from washout studies of inert gases with differing diffusivity. Lastly, we will extend our computational model of the conducting airways to include the acinar structure, which will assist in interpreting the physiologic data and mechanisms contributing to pulmonary dysfunction in infants born prematurely. SPECIFIC AIM # 1: Determine the relationship between parenchymal tissue and alveolar volume with normal lung growth early in life. We hypothesize that during the first two years of life that parenchymal surface area and alveolar volume increase with somatic growth; however, the ratio of surface area to volume remains constant, while ventilation within the lung becomes more homogenous. SPECIFIC AIM # 2: Determine the pulmonary sequelae of premature birth and assess the effectiveness of early treatment strategies upon the pulmonary sequelae. We hypothesize that premature birth impedes growth and development of the lung parenchyma and the airways at a corrected-age of 1-year. In addition, initiating continuous positive airway pressure (CPAP) and a permissive ventilatory strategy in very premature infants at birth will improve lung growth and lung function compared to treatment with early surfactant and conventional ventilation.

描述（由申请人提供）：该提案将采用最新技术来评估婴儿和幼儿中肺实质的正常生长和发育，这是一个重要且困难的年龄组。了解生命早期肺部生长对于设计治疗策略至关重要，以促进肺部疾病婴儿的肺部生长。我们还将评估与早产相关的慢性肺后遗症，并比较两种不同策略的肺结构和功能的影响，以便对非常过早的婴儿进行通气支持。我们的实验室开发了评估婴儿强迫呼气操作的方法，我们已经改编了这项技术来测量婴儿的单呼吸扩散能力，作为对气体交换表面积的体内评估。此外，一种在肺部升高的婴儿中获得高分辨率CT图像的技术，没有呼吸运动的伪影，我们将获得肺实质组织密度以及气道尺寸和壁厚的体内定量测量。肺部内的通风不均匀性也将通过对具有不同扩散率的惰性气体的冲洗研究进行评估。最后，我们将将导电道的计算模型扩展到包括腺泡结构，这将有助于解释生理数据和机制，导致早产婴儿的肺部功能障碍。特定目标＃1：确定实质组织与肺泡体积之间的关系与生命早期肺部正常生长之间的关系。我们假设在生命的头两年中，实质表面积和肺泡体积随体细胞生长而增加。但是，表面积与体积的比率保持恒定，而肺内的通风变得更加同质。特定目的＃2：确定早产过早的肺后遗症，并评估早期治疗策略对肺后遗症的有效性。我们假设早产会阻碍肺实质和气道的生长和发育1年。此外，与早期的表面活性剂和常规通风治疗相比，出生时非常过早的婴儿的持续正气道（CPAP）和允许的通气策略将改善肺部生长和肺功能。