White Luke A, Maxey Benjamin S, Solitro Giovanni F, Takei Hidehiro, Conrad Steven A, Alexander J Steven
Department of Molecular & Cellular Physiology, LSU Health Shreveport, 1501 Kings Highway, Shreveport, LA, 71103-3932, USA.
Department of Orthopedic Surgery, LSU Health Shreveport, Shreveport, LA, USA.
BMC Biomed Eng. 2022 Mar 14;4(1):2. doi: 10.1186/s42490-022-00059-x.
The COVID-19 pandemic revealed a substantial and unmet need for low-cost, easily accessible mechanical ventilation strategies for use in medical resource-challenged areas. Internationally, several groups developed non-conventional COVID-19 era emergency ventilator strategies as a stopgap measure when conventional ventilators were unavailable. Here, we compared our FALCON emergency ventilator in a rabbit model and compared its safety and functionality to conventional mechanical ventilation.
New Zealand white rabbits (n = 5) received mechanical ventilation from both the FALCON and a conventional mechanical ventilator (Engström Carestation™) for 1 h each. Airflow and pressure, blood O saturation, end tidal CO, and arterial blood gas measurements were measured. Additionally, gross and histological lung samples were compared to spontaneously breathing rabbits (n = 3) to assess signs of ventilator induced lung injury.
All rabbits were successfully ventilated with the FALCON. At identical ventilator settings, tidal volumes, pressures, and respiratory rates were similar between both ventilators, but the inspiratory to expiratory ratio was lower using the FALCON. End tidal CO was significantly higher on the FALCON, and arterial blood gas measurements demonstrated lower arterial partial pressure of O at 30 min and higher arterial partial pressure of CO at 30 and 60 min using the FALCON. However, when ventilated at higher respiratory rates, we observed a stepwise decrease in end tidal CO. Poincaré plot analysis demonstrated small but significant increases in short-term and long-term variation of peak inspiratory pressure generation from the FALCON. Wet to dry lung weight and lung injury scoring between the mechanically ventilated and spontaneously breathing rabbits were similar.
Although conventional ventilators are always preferable outside of emergency use, the FALCON ventilator safely and effectively ventilated healthy rabbits without lung injury. Emergency ventilation using accessible and inexpensive strategies like the FALCON may be useful for communities with low access to medical resources and as a backup form of emergency ventilation.
2019冠状病毒病（COVID-19）大流行揭示了在医疗资源匮乏地区对低成本、易于获取的机械通气策略存在大量未得到满足的需求。在国际上，当常规呼吸机无法获得时，几个团队开发了非传统的COVID-19时代紧急呼吸机策略作为权宜之计。在此，我们在兔模型中比较了我们的FALCON紧急呼吸机，并将其安全性和功能与常规机械通气进行了比较。
新西兰白兔（n = 5）分别接受FALCON和常规机械呼吸机（Engström Carestation™）机械通气各1小时。测量气流和压力、血氧饱和度、呼气末二氧化碳以及动脉血气。此外，将大体和组织学肺样本与自主呼吸兔（n = 用FALCON对所有兔子均成功进行了通气。在相同的呼吸机设置下，两台呼吸机的潮气量、压力和呼吸频率相似，但使用FALCON时吸呼比更低。FALCON上的呼气末二氧化碳显著更高，动脉血气测量显示使用FALCON时在30分钟时动脉血氧分压更低，在30和60分钟时动脉血二氧化碳分压更高。然而，当以更高的呼吸频率通气时，我们观察到呼气末二氧化碳逐渐降低。庞加莱图分析表明，FALCON产生的吸气峰压的短期和长期变化有小但显著的增加。机械通气兔和自主呼吸兔之间的肺湿重与干重之比以及肺损伤评分相似。
虽然在非紧急使用情况下常规呼吸机总是更可取，但FALCON呼吸机安全有效地对健康兔子进行了通气且未造成肺损伤。使用像FALCON这样易于获取且廉价的策略进行紧急通气可能对医疗资源获取有限的社区有用，并可作为紧急通气的备用形式。 3）进行比较，以评估呼吸机诱导的肺损伤迹象。
