Chen Yuqing, Cheng Kewen, Zhou Xin
Department of Respiratory Medicine, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, China (mainland).
Department of Respiratory Medicine, Huashan Hospital Baoshan Branch, Fudan University, Shanghai, China (mainland).
Med Sci Monit. 2015 Jan 26;21:310-7. doi: 10.12659/MSM.892080.
Pressure support ventilation from a bilevel device is a standard technique for non-invasive home ventilation. A bench study was designed to compare the performance and patient-ventilator synchronization of 7 bilevel ventilators, in the presence of system leaks.
MATERIAL/METHODS: Ventilators were connected to a Hans Rudolph Series 1101 lung simulator (compliance, 50 mL/cmH2O; expiratory resistance, 20 cmH2O/L/s; respiratory rate, 15 breaths/min; inspiratory time, 1.0 s). All ventilators were set at 15 cmH2O pressure support and 5 cmH2O positive end-expiratory pressure. Tests were conducted at 2 system leaks (12-15 and 25-28 L/min). The performance characteristics and patient-ventilator asynchrony were assessed, including flow, airway pressure, time, and workload.
The Breas Vivo30 could not synchronize with the simulator (frequent auto-triggering) at a leak of 25-28 L/min, but provided stable assisted ventilation when the leak was 12-15 L/min. Missed efforts and back-up ventilation occurred for the Weinmann VENTImotion and Airox Smartair Plus, requiring adjustment of trigger effort. All ventilators had a short trigger delay time (<200 ms), but significant differences between devices were found in triggering workload, pressurization appearance, tidal volume, and peak inspiratory flow. Premature cycling was frequent when the inspiratory termination criteria were at the highest sensitivity. Cycling synchronization was considerably improved by modifying expiratory triggering sensitivity settings, when available.
Performance and triggering workload varied significantly between bilevel ventilators, possibly due to software algorithm differences. Adjusting the cycling criteria settings can alter the shape of the inspiratory phase and peak expiratory flow, and improve patient-ventilator synchrony.
双水平设备的压力支持通气是无创家庭通气的标准技术。一项实验台研究旨在比较7台双水平呼吸机在存在系统泄漏情况下的性能和患者-呼吸机同步性。
材料/方法：将呼吸机连接到汉斯·鲁道夫1101型肺模拟器（顺应性为50 mL/cmH₂O；呼气阻力为20 cmH₂O/L/s；呼吸频率为15次/分钟；吸气时间为1.0秒）。所有呼吸机均设置为15 cmH₂O的压力支持和5 cmH₂O的呼气末正压。在2种系统泄漏情况（12 - 15 L/分钟和25 - 28 L/分钟）下进行测试。评估了性能特征和患者-呼吸机不同步情况，包括流量、气道压力、时间和工作量。
在泄漏量为25 - 28 L/分钟时，Breas Vivo30无法与模拟器同步（频繁自动触发），但当泄漏量为12 - 15 L/分钟时可提供稳定的辅助通气。伟曼VENTImotion和艾瑞克斯Smartair Plus出现了触发失败和备用通气情况，需要调整触发力度。所有呼吸机的触发延迟时间均较短（<200毫秒），但在触发工作量、增压表现、潮气量和吸气峰流量方面，不同设备之间存在显著差异。当吸气终止标准设置为最高灵敏度时，过早切换频繁发生。如有可用的呼气触发灵敏度设置，通过修改该设置可显著改善切换同步性。
双水平呼吸机之间的性能和触发工作量差异显著，可能是由于软件算法不同。调整切换标准设置可改变吸气相形状和呼气峰流量，并改善患者-呼吸机同步性。
