Park Min Ho, Sung Ki Sub, Kim Ji Hoon, Myung Jinwoo, Hong Ju Young
Department of Emergency Medicine, Yonsei University College of Medicine, Seoul, Korea.
SS-ENG Co Ltd, Bucheon, Korea.
Clin Exp Emerg Med. 2024 Mar;11(1):59-67. doi: 10.15441/ceem.23.067. Epub 2023 Nov 29.
The efficacy of previously developed respiratory barrier enclosures to limit healthcare workers' exposure to aerosols from COVID-19 patients remains unclear; in addition, the design of these devices is unsuitable for transportation or other emergency procedures. Therefore, we developed a novel negative pressure respiratory isolator to improve protection from patient-generated aerosols and evaluated its protective effect in conversion to systemic isolator.
This in vitro study simulated droplets by nebulizing 1% glycerol + 99% ethanol solution. We performed cardiopulmonary resuscitation (CPR) and converted a respiratory barrier enclosure into a systemic isolator with a respiratory barrier as well as a respiratory barrier with negative pressure generator (NPG), which were compared with control and room air. During the procedure, particles were counted for 30 seconds and the count was repeated 10 times.
During CPR, the total number of particles in the respiratory barrier with NPG (280,529; interquartile range [IQR], 205,263-359,195; P=0.970) was similar to that in the control (308,789; IQR, 175,056-473,276). Using NPG with a respiratory barrier reduced the number of particles to 27,524 (IQR, 26,703- 28,905; P=0.001). Particle number during conversion of the respiratory barrier into a systemic isolator was also lower than in the control (25,845; IQR, 19,391- 29,772; P=0.001).
The novel isolator was converted to a systemic isolator without air leakage. The aerosol-blocking effect of the isolator was quantified using a particle counter during CPR. Further studies comparing the barrier effect of isolators within various pressure differentials are warranted.
先前开发的呼吸屏障罩限制医护人员接触新冠患者气溶胶的效果尚不清楚；此外，这些装置的设计不适合运输或其他紧急程序。因此，我们开发了一种新型负压呼吸隔离器，以增强对患者产生的气溶胶的防护，并评估其在转换为全身隔离器时的防护效果。
这项体外研究通过雾化1%甘油+99%乙醇溶液来模拟飞沫。我们进行了心肺复苏（CPR），并将呼吸屏障罩转换为带有呼吸屏障的全身隔离器以及带有负压发生器（NPG）的呼吸屏障，将其与对照组和室内空气进行比较。在操作过程中，对颗粒计数30秒，并重复计数10次。
在心肺复苏期间，带有NPG的呼吸屏障中的颗粒总数（280,529；四分位间距[IQR]，205,263 - 359,195；P = 0.970）与对照组（308,789；IQR，175,056 - 473,276）相似。使用带有呼吸屏障的NPG可将颗粒数减少至27,524（IQR，26,703 - 28,905；P = 0.001）。呼吸屏障转换为全身隔离器期间的颗粒数也低于对照组（25,845；IQR，19,391 - 29,772；P = 0.001）。
新型隔离器可转换为无空气泄漏的全身隔离器。在心肺复苏期间使用颗粒计数器对隔离器的气溶胶阻断效果进行了量化。有必要进一步研究比较不同压差下隔离器的屏障效果。
