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

项目摘要 气溶胶产生程序(AGP)是一种产生气溶胶的医疗程序，这种程序可能会携带 如果患者有病毒感染，如SARS-CoV-2或fl病毒感染，就会感染病原体。这些气雾剂构成了一种明显的fi不能 对医护人员的风险，因为他们可以在空气中停留很长一段时间，而且足够小， 绕过普通的医用口罩。目前还没有确定的、明确的方法来评估 与特定fic agp相关的医护人员，也没有一种严格的方法来评估建议的 风险缓解战略。为了解决这一差距，必须开发一种可应用的flow可视化技术 在实际医疗过程中的临床环境中，能够检测产生的气雾剂flOWS 通过AGP或潜在的AGP。 在这个R21方案中，我们将采用flUID中的一种方法--面向背景的纹影可视化 力学，转化为一种可用于研究AGP产生的flOW的技术。R21项目很高 风险，没有公布的初步数据，但PI已经成功地展示了气溶胶的可视化 由喷射通风公司生产，这是一种特殊的fic型agp，在概念验证实验中使用了bos。建议数 这项工作显然是不可能和及时的，因为评估与fi相关的风险在 新冠肺炎大流行的背景下。我们将使用新的BOS技术来评估风险和评估缓解 体外和体内条件下三种fic-AGP的策略。 Speciific目标1：开发一个人类规模的BOS系统，并建立评估风险的程序 在临床环境中的应用。 SPECIfic目标2：量化不同模拟和体内条件下气溶胶暴露的风险， 并确定降低风险的策略。 拟议研究的重要意义和影响将是开发一种工具，用于明确评估--fi 在现实的临床环境中确定与AGP相关的风险，并对三个国家进行迫切需要的风险评估 SPECIfic AGP并通过实验验证了每个AGP的风险缓解策略。

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.