Resuscitation Science Center of Emphasis, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
Mil Med. 2024 Aug 19;189(Suppl 3):823-831. doi: 10.1093/milmed/usae295.
Despite the significant need for mechanical ventilation in- and out-of-hospital, mechanical ventilators remain inaccessible in many instances because of cost or size constraints. Mechanical ventilation is especially critical in trauma scenarios, but the impractical size and weight of standard mechanical ventilators restrict first responders from carrying them in medical aid bags, leading to reliance on imprecise manual bag-mask ventilation. This is particularly important in combat-related injury, where airway compromise and respiratory failure are leading causes of preventable death, but medics are left without necessary mechanical ventilation. To address the serious gaps in mechanical ventilation accessibility, we are developing an Autonomous, Modular, and Portable Ventilation platform (AMP-Vent) suitable for austere environments, prolonged critical care, surgical applications, mass casualty incidents, and stockpiling. The core system is remarkably compact, weighing <2.3 kg, and can fit inside a shoebox (23.4 cm × 17.8 cm × 10.7 cm). Notably, this device is 65% lighter than standard transport ventilators and astoundingly 96% lighter than typical intensive care unit ventilators. Beyond its exceptional portability, AMP-Vent can be manufactured at less than one-tenth the cost of conventional ventilators. Despite its reduced size and cost, the system's functionality is uncompromised. The core system is equipped with closed-loop sensors and advanced modes of ventilation (pressure-control, volume-control, and synchronized intermittent mandatory ventilation), enabling quality care in a portable form factor. The current prototype has undergone preliminary preclinical testing and optimization through trials using a breathing simulator (ASL 5000) and in a large animal model (swine). This report aims to introduce a novel ventilation system and substantiate its promising performance through evidence gathered from preclinical studies.
Lung simulator testing was performed using the ASL 5000, in accordance with table 201.105 "pressure-control inflation-type testing" from ISO 80601-2-12:2020. Following simulations, AMP-Vent was tested in healthy 10-kg female domestic piglets. The Children's Hospital of Philadelphia Institutional Animal Care and Use Committee approved all animal procedures. Swine received 4-min blocks of alternating ventilation, where AMP-Vent and a conventional anesthesia ventilator (GE AISYS CS2) were used to titrate to varied end-tidal carbon dioxide (EtCO2) goals with the initial ventilator switching for each ascending target (35, 40, 45, 50, 55 mmHg).
During ASL 5000 simulations, AMP-Vent exhibited consistent performance under varied conditions, maintaining a coefficient of variation of 2% or less within each test. In a large animal study, AMP-Vent maintained EtCO2 and SpO2 targets with comparable performance to a conventional anesthesia ventilator (GE AISYS CS2). Furthermore, the comparison of minute ventilation (Ve) distributions between the conventional anesthesia ventilator and AMP-Vent at several EtCO2 goals (35, 40, 45, 50, and 55 mmHg) revealed no statistically significant differences (p = 0.46 using the Kruskal-Wallis rank sum test).
Preclinical results from this study highlight AMP-Vent's core functionality and consistent performance across varied scenarios. AMP-Vent sets a benchmark for portability with its remarkably compact design, positioning it to revolutionize trauma care in previously inaccessible medical scenarios.
尽管在医院内外对机械通气的需求巨大,但由于成本或尺寸限制,许多情况下仍无法获得机械呼吸机。机械通气在创伤情况下尤为关键,但标准机械呼吸机的体积和重量不实用,限制了第一响应者将其携带在医疗急救包中,导致依赖不精确的手动袋面罩通气。这在与战斗相关的伤害中尤为重要,其中气道阻塞和呼吸衰竭是可预防死亡的主要原因,但医务人员没有必要的机械通气。为了解决机械通气可及性方面的严重差距,我们正在开发一种适用于恶劣环境、长期重症监护、手术应用、大规模伤亡事件和储备的自主、模块化和便携式通气平台 (AMP-Vent)。核心系统非常紧凑,重量<2.3 公斤,可装在鞋盒内(23.4 厘米×17.8 厘米×10.7 厘米)。值得注意的是,该设备比标准运输呼吸机轻 65%,比典型的重症监护室呼吸机轻 96%。除了其出色的便携性外,AMP-Vent 的制造成本不到传统呼吸机的十分之一。尽管体积和成本有所降低,但系统的功能并未妥协。核心系统配备了闭环传感器和先进的通气模式(压力控制、容量控制和同步间歇强制通气),可在便携式外形尺寸下提供高质量的护理。目前的原型已经通过使用呼吸模拟器 (ASL 5000) 和大型动物模型(猪)进行的初步临床前测试和优化得到了验证。本报告旨在介绍一种新型通气系统,并通过临床前研究中收集的证据证明其性能可靠。
根据 ISO 80601-2-12:2020 表 201.105“压力控制充气式测试”的规定,在 ASL 5000 上进行肺模拟器测试。模拟后,在健康的 10 公斤雌性家猪仔猪上测试 AMP-Vent。费城儿童医院机构动物护理和使用委员会批准了所有动物程序。猪接受了 4 分钟的交替通气块,AMP-Vent 和传统麻醉呼吸机 (GE AISYS CS2) 用于根据初始呼吸机切换到不同的呼气末二氧化碳 (EtCO2) 目标(35、40、45、50、55mmHg)进行滴定。
在 ASL 5000 模拟中,AMP-Vent 在各种条件下表现一致,在每个测试中保持 2%或更低的变异系数。在一项大型动物研究中,AMP-Vent 以与传统麻醉呼吸机 (GE AISYS CS2) 相当的性能维持 EtCO2 和 SpO2 目标。此外,在几个 EtCO2 目标(35、40、45、50 和 55mmHg)下,比较传统麻醉呼吸机和 AMP-Vent 的分钟通气量 (Ve) 分布,没有发现统计学上的显著差异(Kruskal-Wallis 秩和检验,p=0.46)。
本研究的临床前结果突出了 AMP-Vent 在各种情况下的核心功能和一致性能。AMP-Vent 以其非常紧凑的设计树立了便携性的基准,有望彻底改变以前无法进入的医疗环境中的创伤护理。