无创正压通气时不同呼吸力学特性对呼气切换同步性的影响  

Influence of expiratory trigger sensitivity setting on inspiratory cycling-off synchronization during noninvasive pressure support ventilation with different respiratory mechanics

作　　者：陈宇清[1] 张杏怡[1] 丁凤鸣[1] 程克文[2] 周新[1] 

机构地区：[1]上海交通大学附属第一人民医院呼吸科,200080 [2]复旦大学附属华山医院宝山分院

出　　处：《中国医师进修杂志》2016年第2期117-122,共6页Chinese Journal of Postgraduates of Medicine

基　　金：国家自然科学基金（8130005）

摘　　要：目的观察无创正压通气时不同呼气触发灵敏度（ETS）设置在不同呼吸力学特性条件下对呼气切换同步的影响。方法使用Series 1101机械肺模拟器分别模拟正常呼吸力学、高气道阻力和低胸肺顺应性状态，使用Flexo ST30无创双水平正压呼吸机进行测试。通气模式为压力支持通气（PSV），参数为10 cmH2O（正常成年人时，1 cmH2O = 0.098 kPa）和15 cmH2O的压力支持及5 cmH2O的呼气末正压，后备通气频率为10次／min。收集在泄漏量为24- 28 L/min时的通气参数。结果不同呼吸力学特性条件下，呼吸机输出的吸气峰流量（PIF）和呼气峰流量（PEF）均不相同，潮气量、PEF和吸气时间随着ETS水平的降低而逐渐增大。低胸肺顺应性和正常呼吸力学状态时，呼气过早切换现象极易出现，仅ETS为低水平时，出现轻度呼气切换延迟，呼气切换延迟时间分别为（15.20 ± 0.43）ms和（105.00 ± 15.82）ms，此时流量切换比值约为5%。高气道阻力状态时，呼吸机输出的PIF和PEF明显降低，中、高水平ETS时均呈现为呼气延迟切换，高水平ETS时呼气切换延迟时间较中水平短[（51.30 ± 12.63）ms与（162.40 ± 15.59） ms]，流量切换比值较中水平增高[（34.52 ± 3.36）％与（16.04 ± 2.58）%]，差异有统计学意义（P〈0.05），低水平ETS水平时出现严重的延迟切换。结论Flexo ST30无创双水平正压呼吸机的ETS调节范围在5%- 35%。不同呼吸力学状态会对呼吸机的呼气切换同步性产生显著的影响，高水平ETS设置有利于改善高气道阻力患者的呼气切换同步，但对于低胸肺顺应性患者和正常成年人易造成明显的过早切换。Objective To compare the inspiratory cycling-off synchronization with expiratory trigger sensitivity （ETS） setting during noninvasive pressure support ventilation （PSV） under the different conditions of respiratory mechanics. Methods Bi-level pressure ventilator was connected to a lung model （Hans Rudolph Series1101 simulator）. And its mechanics was set to normal, obstructive and restrictive ventilation dysfunction. Tests were performed with pressure support levels of 10 （in normal condition, 1 cmH2O = 0.098 kPa） and 15 cmH2O, 5 cmH2O positive end-expiratory pressure （PEEP）. The data including cycling delay time （Td）, tidal volume （TV） and airflow were collected in the presence of air leaks （24 - 28 L/min）. Results Significant performance on airflow was observed in various respiratory mechanics conditions. The peak inspiratory flow （PIF） and peak expiratory flow （PEF） were different, and the tidal volume, PEF and inspiratory time were increased after decreasing the ETS level. Premature cycling occurred frequently in normal and restrictive model. Delay cycling was found only when the ETS setting was at the lowest level （about 5% of PIF）, at which Td were （15.20 ± 0.43） ms and （105.00 ±15.82） ms. In obstructive model, PIF and PEF were significantly decreased, and delay cycling was always present. Td were increased after the ETS setting was changed from the most sensitive level to moderate level： （51.30 ± 12.63） ms vs. （162.40 ± 15.59） ms, as cyclingoff criteria Were reduced from （34.52 ± 3.36）% to （16.04 ± 2.58）% of PIF, and there were statistical differences （P 〈 0.05）. Severe delay cycling was found when the ETS level was at the lowest level. Conclusions There are significant differences in performances and cycling-off synchrony in various respiratory mechanics models during PSV. For Curative Flexo ST30 hi-level pressure ventilator, its flow cycling-off criteria range is about 5% - 35% of PIF. The higher ETS level might be beneficia

关 键 词：呼吸 人工 正压呼吸 呼吸力学 

分 类 号：R56[医药卫生—呼吸系统]