Hung T-Y, Yu S-H, Chen Y-C, Su Y-C, Chen H-L, Wu B-H, Hu S-C, Lin T
Department of Emergency Medicine, Zhong-Xing Branch, Taipei City Hospital, Taipei City, Taiwan; Faculty of Medicine, National Yang-Ming Chiao Tung University, Hsinchu, Taiwan; CrazyatLAB (Critical Airway Training Laboratory), Taipei City, Taiwan.
Department of Emergency Medicine, Zhong-Xing Branch, Taipei City Hospital, Taipei City, Taiwan.
J Hosp Infect. 2025 Jan;155:198-208. doi: 10.1016/j.jhin.2024.11.008. Epub 2024 Nov 19.
This study evaluated aerosol exposure during various respiratory activities (breathing, tachypnea, coughing, and oxygen therapy) in environments with directional air purifiers (DAPs), HEPA evacuators, and standard negative pressure (SNP) rooms to explore potential alternatives for addressing isolation room shortages.
Aerosol exposure was measured during various breathing conditions (normal, tachypnea, coughing, and recovery) with non-rebreather masks (NRMs) and nasal cannulas. The study analysed aerosol velocity and concentrations at the head, trunk and feet of a mannequin across settings including DAP, HEPA evacuator, SNP room, their combinations, and a reference group without intervention.
The DAP, HEPA evacuator and SNP environment all reduced aerosol build-up compared with the control group. The DAP and HEPA evacuator were consistently more effective than the SNP environment, especially during activities that increase expiratory flow. The HEPA evacuator showed higher aerosol concentrations at the head compared with the DAP when used with NRMs or nasal cannulas. Both the DAP and HEPA demonstrated better aerosol clearance than the SNP environment when minute ventilation exceeded 10 L/min.
DAP and HEPA evacuators provide effective aerosol reduction, suggesting their utility as alternatives to SNP isolation rooms during pandemics. While SNP environments continuously ventilate the space, DAP and HEPA evacuators are more efficient in early aerosol removal, preventing accumulation. However, aerosols dispersing in multiple directions during oxygen therapy can challenge the HEPA evacuator's single-point suction, unlike the broader coverage offered by the DAP.
本研究评估了在配备定向空气净化器（DAP）、高效空气过滤器抽气机和标准负压（SNP）病房的环境中，在各种呼吸活动（呼吸、呼吸急促、咳嗽和氧疗）期间的气溶胶暴露情况，以探索应对隔离病房短缺的潜在替代方案。
使用非重复呼吸面罩（NRM）和鼻导管在各种呼吸条件（正常、呼吸急促、咳嗽和恢复）下测量气溶胶暴露。该研究分析了在包括DAP、高效空气过滤器抽气机、SNP病房、它们的组合以及无干预对照组在内的不同环境中，人体模型头部、躯干和脚部的气溶胶速度和浓度。
与对照组相比，DAP、高效空气过滤器抽气机和SNP环境均减少了气溶胶的积聚。DAP和高效空气过滤器抽气机始终比SNP环境更有效，尤其是在增加呼气流量的活动期间。当与NRM或鼻导管一起使用时，高效空气过滤器抽气机在头部显示出比DAP更高的气溶胶浓度。当分钟通气量超过10升/分钟时，DAP和高效空气过滤器在清除气溶胶方面均比SNP环境表现更好。
DAP和高效空气过滤器抽气机可有效减少气溶胶，表明它们在大流行期间可作为SNP隔离病房的替代方案。虽然SNP环境持续对空间进行通风，但DAP和高效空气过滤器抽气机在早期去除气溶胶方面更有效，可防止其积聚。然而，与DAP提供的更广泛覆盖范围不同，氧疗期间向多个方向分散的气溶胶可能对高效空气过滤器抽气机的单点抽吸构成挑战。
