不同海拔下经鼻高流量湿化氧疗仪性能测试

Performance test of high-flow nasal cannula oxygen therapy device at different altitudes

目的:研究不同海拔下不同品牌和型号的经鼻高流量湿化氧疗(high-flow nasal cannula oxygen therapy,HFNC)仪的性能。方法:选取R-80S双水平无创呼吸机-HFNC仪一体机、HF-60A HFNC仪、HFT-300 HFNC仪、H-80A HFNC仪4台HFNC仪,将HFNC仪连接至气体流量计、模拟人头及夹板模拟肺后放置于低压舱中。设置HFNC仪的流量为10、15、20、25、30、35、40、45、50、55、60 L/min,并设置低压舱模拟海拔分别为6000、5000、4000、3000、2000、1000、0 m。记录4台HFNC仪在不同设置海拔和流量下的实际输出气道流量、气道压力变化及趋势。采用SPSS 25.0软件进行统计学分析。结果:在6000 m模拟海拔内且设置流量保持不变的情况下,4台HFNC仪的实际输出气道流量均随着海拔升高呈现上升趋势,但超过一定海拔和设置流量之后,实际输出气道流量升高缓慢,甚至呈下降趋势,其随海拔高度的增加而变化的程度各不相同,且没有统一规律。另外,随着海拔升高,4台HFNC仪在设置流量为10~35 L/min范围时的实际输出气道压力也随之逐渐升高,当设置流量超过35 L/min时,其实际输出气道压力随海拔升高至一定数值(转折点)后出现下降趋势,且总体上设置流量越高,出现转折点的海拔越低。结论:在高海拔环境使用HFNC仪进行氧疗时,应注意其实际输出气道流量升高、气道压力增大的情况,需结合患者实际所需气道压力、舒适度及患者长期居住海拔高度综合考虑HFNC仪的流量设置。

Objective To investigate the performance of brands and types of high-flow nasal cnnula oxygen therapy(HFNC)devices at different altitudes.Methods Four different models of HFNC devices,including R-80S bi-level non-invasive ventilator integrated with HFNC device,HF-60A HFNC device,HFT-300 HFNC device and H-80A HFNC device,were connected with the gas flow meter,simularted head and QuickLung and then put into a low-pressure chamber.The flow rates of the HFNC devices were set to 10,15,20,25,30,35,40,45,50,55 and 60 L/min,and the simulated altitudes of the low-pressure chamber were set to 6000,5000,4000,3000,2000,1000 and 0 m.The actual output airway flow rates,airway pressure changes and trends of the four HFNC devices were recorded at different setting altitudes and flow rates.SPSS 25.0 software was used for statistical analysis.Results The actual output airway flow rates of the four HFNC devices showed an increasing trend as the altitude rose with the simulated altitude of 6000 m and the setting flow rate kept constant,which increased slowly and even went to decrease when the altitude and flow rate exceeded some limits.The degree of changes in the flow rate with the increasing altitude varied,and there was no uniform pattern.With the rising of altitude,the actual output airway pressure of the four HFNC devices with the flow rate raning from 10 to 35 L/min also increased gradually,which showed a decreasing trend(turning point)after going up to some certain value when the flow rate exceeded 35 L/min,and the altitude where the turning point appeared was lowered as the flow rate increased.Conclusion The actual output airway flow rates and airway pressure during HFNC rise at a high-altitude environment,and generally considerations have to be taken on required airway pressure,patient comfort and the altitude of the patient's usual place of residence when setting the flow rates of the HFNC device.