Background Oriented Schlieren (BOS) Visualization for Evaluation of Risk in Aerosol-Generating Procedures

项目摘要 气溶胶生成程序（AGPs）是产生气溶胶的医疗程序，所述气溶胶可以装载有 病原体，如果病人有病毒感染，如SARS-CoV-2或在Eschuenza。这些气溶胶构成了一个重要的 对卫生保健工作者的风险，因为它们可以在空气中停留很长一段时间，而且足够小， 绕过普通的外科口罩目前还没有确定的、明确的方法来评估 与特定AGP相关的医疗保健工作者，也没有严格的方法来评估拟议的 风险缓解战略。为了弥补这一差距，必须开发一种可应用于 并且能够检测所产生的载有气溶胶的气流 或潜在的AGP。 在这个R21提案中，我们将采用面向背景的纹影（BOS）可视化，这是一种来自于EQUIPUID的方法 力学，转化为一种技术，可应用于研究由AGP产生的水流。R21项目高 风险，没有公布的初步数据，但PI已经成功地证明了气溶胶的可视化 通过喷射通风产生，一种特殊类型的AGP，在概念验证实验中使用BOS。拟议 这项工作是重要和及时的，因为评估与AGP相关的风险在 COVID-19疫情的背景下。我们将使用新的BOS技术来评估风险和评估缓解措施 在离体和体内条件下三种特异性AGP的策略。 具体目标1：开发人类规模的BOS系统，并建立风险评估程序 在临床环境中的应用。 具体目标2：量化不同模拟和体内条件下的气溶胶暴露风险， 并确定减轻风险的战略。 拟议研究的意义和影响将是开发一种明确评估的工具， 在现实的临床环境中与AGPs相关的风险，以及三个迫切需要的风险评估 特定的AGP和针对每个AGP的经过实验验证的艾德风险缓解策略。

Project Summary Aerosol-generating procedures (AGPs) are medical procedures that produce aerosols that can be laden with pathogens if the patient has a viral infection, such as SARS-CoV-2 or influenza. These aerosols pose a significant risk to health care workers, as they can linger in the air for extended periods of time and are small enough to bypass ordinary surgical masks. There is currently no established, unambiguous way to evaluate the risks to healthcare workers associated with a specific AGP, nor is there a rigorous method by which to assess a proposed risk-mitigation strategy. To address this gap, a flow visualization technique must be developed that can be applied in a clinical setting during actual medical procedures and is capable of detecting aerosol-laden flows produced by AGPs or potential AGPs. In this R21 proposal, we will adapt background-oriented schlieren (BOS) visualization, a method from fluid mechanics, into a technique that can be applied to study flows produced by AGPs. The R21 project is high risk with no published preliminary data, but the PIs have successfully demonstrated visualziation of aerosols produced by jet ventilation, a specific type of AGP, using BOS in a proof-of-concept experiment. The proposed work is significant and timely, as assessment of the risk associated with AGPs is extremely important in the context of the COVID-19 pandemic. We will use the novel BOS technique to assess risks and evaluate mitigation strategies for three specific AGPs in both ex vivo and in vivo conditions. Specific Aim 1: Develop a human-scale BOS system and establish a procedure for evaluating the risk of AGPs in a clinical setting. Specific Aim 2: Quantify the risk of aerosol exposure under different simulated and in-vivo conditions, and identify strategies to mitigate the risks. The significance and impact of the proposed research will be in developing a tool for unambiguously evaluat- ing the risks associated with AGPs in realistic clinical settings, and urgently-needed risk assessments for three specific AGPs and experimentally verified risk mitigation strategies for each.