Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa, New Zealand.
Department of Anesthesia, University of Iowa, Iowa City, Iowa.
Int J Numer Method Biomed Eng. 2019 Oct;35(10):e3238. doi: 10.1002/cnm.3238. Epub 2019 Aug 6.
The purpose of this study was to assess the potential for optimization of mechanical ventilator waveforms using multiple frequencies of oscillatory flow delivered simultaneously to minimize the risk of ventilator-induced lung injury (VILI) associated with regional strain, strain rate, and mechanical power. Optimization was performed using simulations of distributed oscillatory flow and gas transport in a computational model of anatomically derived branching airway segments and viscoelastic terminal acini under healthy and injured conditions. Objective functions defined by regional strain or strain rate were minimized by single-frequency ventilation waveforms using the highest or lowest frequencies available, respectively. However, a mechanical power objective function was minimized by a combination of multiple frequencies delivered simultaneously. This simulation study thus demonstrates the potential for multifrequency oscillatory ventilation to reduce regional mechanical power in comparison to single-frequency ventilation, and thereby reduce the risk of VILI.
本研究旨在评估使用多种频率的振荡流同时输送以优化机械呼吸机波形的潜力，以最大程度地降低与区域应变、应变率和机械功率相关的呼吸机诱导性肺损伤（VILI）的风险。通过在解剖衍生的分支气道段和粘弹性终端腺泡的计算模型中模拟分布的振荡流和气体传输，对优化进行了仿真。通过分别使用最高或最低可用频率的单频通气波形，最小化由区域应变或应变率定义的目标函数。然而，通过同时输送多个频率的组合来最小化机械功率目标函数。因此，这项模拟研究表明，与单频通气相比，多频振荡通气具有降低区域机械功率的潜力，从而降低 VILI 的风险。
