DataSheet1_Full-lung simulations of mechanically ventilated lungs incorporating recruitment/derecruitment dynamics.docx

This study developed and investigated a comprehensive multiscale computational model of a mechanically ventilated ARDS lung to elucidate the underlying mechanisms contributing to the development or prevention of VILI. This model is built upon a healthy lung model that incorporates realistic airway and alveolar geometry, tissue distensibility, and surfactant dynamics. Key features of the ARDS model include recruitment and derecruitment (RD) dynamics, alveolar tissue viscoelasticity, and surfactant deficiency. This model successfully reproduces realistic pressure-volume (PV) behavior, dynamic surface tension, and time-dependent descriptions of RD events as a function of the ventilation scenario. Simulations of Time-Controlled Adaptive Ventilation (TCAV) modes, with short and long durations of exhalation (TLow- and TLow+, respectively), reveal a higher incidence of RD for TLow+ despite reduced surface tensions due to interfacial compression. This finding aligns with experimental evidence emphasizing the critical role of timing in protective ventilation strategies. Quantitative analysis of energy dissipation indicates that while alveolar recruitment contributes only a small fraction of total energy dissipation, its spatial concentration and brief duration may significantly contribute to VILI progression due to its focal nature and higher intensity. Leveraging the computational framework, the model may be extended to facilitate the development of personalized protective ventilation strategies to enhance patient outcomes. As such, this computational modeling approach offers valuable insights into the complex dynamics of VILI that may guide the optimization of ventilation strategies in ARDS management.

本研究开发并研究了一套针对机械通气的急性呼吸窘迫综合征（Acute Respiratory Distress Syndrome, ARDS）肺的多尺度综合计算模型，旨在阐明呼吸机诱导肺损伤（Ventilator-Induced Lung Injury, VILI）发生与预防的潜在机制。该模型以整合了真实气道与肺泡几何结构、组织顺应性及表面活性物质动力学的健康肺模型为基础构建。ARDS模型的核心特征包括复张与去复张（Recruitment and Derecruitment, RD）动力学、肺泡组织粘弹性以及表面活性物质缺乏。该模型可复现真实的压力-容积（Pressure-Volume, PV）特性、动态表面张力，以及随通气工况变化的RD事件时间依赖性表征。针对时间控制自适应通气（Time-Controlled Adaptive Ventilation, TCAV）模式的模拟实验中，分别设置短呼气时长与长呼气时长（TLow-与TLow+），结果显示尽管TLow+工况下界面压缩可降低表面张力，但其RD事件发生率反而更高，该发现与相关实验证据一致，后者强调了通气时机在肺保护性通气策略中的关键作用。能量耗散的定量分析表明，尽管肺泡复张仅占总能量耗散的一小部分，但其空间聚集性与短暂的持续时间，加之局灶性分布与更高的作用强度，可能会显著加速VILI的进展。依托该计算框架，本模型可进一步拓展，助力个性化肺保护性通气策略的开发以改善患者预后。综上，该计算建模方法为VILI的复杂动力学机制提供了宝贵见解，可指导ARDS临床管理中通气策略的优化。