Traditionally, NASA mission planners have used a heuristic and qualitative approach to design medical systems based on prior experience; however, this approach may result in implicit bias in design. The risk of needing to return to definitive care (RTDC) or medevac, has been particularly difficult to quantify due to the complexity of exploration spaceflight. The Informing Mission Planning through Analysis of Complex Tradespaces (IMPACT) tool is a probabilistic risk assessment approach designed by NASA to model medical risk in long duration spaceflight. This paper discusses how this tool can inform RTDC risk and improve the health and safety of astronaut crews. IMPACT was developed by subject matter experts using an evidence-based approach and can be used to quantify the risk of exceeding the onboard medical capabilities. Within the model, RTDC occurs when a condition meets a specific threshold that exceeds the on-board capabilities and requires a higher level of care. A notional lunar surface design reference mission (DRM) was modeled using IMPACT, and the RTDC rate was analyzed. Of the 119 medical conditions evaluated, thirty-four were preassigned to have zero probability of RTDC based on lack of acuity. Thirty-one conditions used the need for inpatient hospitalization or admission to intensive care as the RTDC surrogate. Twenty-six conditions used the probability of needing surgery, and ten conditions used treatment failure rates as the RTDC surrogate. The remaining 18 conditions had unique surrogates that did not fall into the above categories or were assigned a 100 % probability of RTDC due to their definition. In the sample DRM, the overall risk for RTDC was 0.32 events per mission. Quantifying medical risk for human spaceflight is challenging but important in designing medical systems that support the health and performance of our astronaut crews. IMPACT can use the best available evidence to quantify the risk of an RTDC event based on mission parameters and help mission planners make informed design decisions. More work is underway to further refine the model and evidence that drives the RTDC calculation to improve model fidelity and utility for missions to the Moon, Mars, and beyond.

中文翻译：

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量化航天中医疗后送的风险


传统上，NASA 任务规划者根据先前的经验使用启发式和定性方法来设计医疗系统。然而，这种方法可能会导致设计中的隐性偏差。由于探索太空飞行的复杂性，需要返回明确护理 (RTDC) 或医疗后送的风险特别难以量化。通过复杂交易空间分析告知任务规划 (IMPACT) 工具是 NASA 设计的一种概率风险评估方法，用于对长时间太空飞行中的医疗风险进行建模。本文讨论了该工具如何告知 RTDC 风险并改善宇航员的健康和安全。 IMPACT 由主题专家采用基于证据的方法开发，可用于量化超出机上医疗能力的风险。在该模型中，当某种情况达到超出机载能力的特定阈值并需要更高级别的护理时，就会发生 RTDC。使用 IMPACT 对概念性月球表面设计参考任务 (DRM) 进行建模，并分析 RTDC 速率。在评估的 119 种医疗状况中，有 34 种因缺乏敏锐度而被预先指定为 RTDC 的可能性为零。 31 种情况使用住院治疗或进入重症监护室的需要作为 RTDC 替代。 26 种情况使用需要手术的概率，10 种情况使用治疗失败率作为 RTDC 替代指标。其余 18 种情况具有独特的替代项，这些替代项不属于上述类别，或者由于其定义而被指定为 100% 的 RTDC 概率。在示例 DRM 中，RTDC 的总体风险为每个任务 0.32 个事件。 量化载人航天的医疗风险具有挑战性，但对于设计支持宇航员健康和表现的医疗系统非常重要。 IMPACT 可以使用最佳可用证据根据任务参数量化 RTDC 事件的风险，并帮助任务规划人员做出明智的设计决策。更多的工作正在进行中，以进一步完善驱动 RTDC 计算的模型和证据，以提高模型保真度和月球、火星及其他任务的实用性。