Sun Yu-Han, Dai Bing, Peng Yun, Tan Wei, Zhao Hong-Wen
Department of Respiratory Medicine, First Affiliated Hospital of China Medical University, Shenyang, China.
Clin Respir J. 2019 Dec;13(12):758-764. doi: 10.1111/crj.13087. Epub 2019 Sep 8.
It is unknown if set-flow, peak inspiratory flow (PIF), tidal volume and set fraction of inspired O (FiO ) affect actual-FiO and positive end-expiratory pressure (PEEP) during high-flow nasal cannula (HFNC) oxygen therapy. In addition, the extent of their influence is also unknown.
To investigate the effects of set-FiO , set-flow, PIF and tidal volume on the actual-FiO and PEEP during HFNC oxygen therapy.
A lung simulation model was used to study the factors that might affect FiO and PEEP during HFNC therapy in vitro. These factors included set-flow (20, 40, 60, 80 and 120 L/min), PIF (40, 80 and 120 L/min), tidal volume (400 and 600 mL), and set-FiO (30%, 50% and 70%). Actual-FiO and PEEP were recorded for 10 consecutive breaths. Actual-FiO and PEEP were compared under different conditions. Multivariate linear regressions were performed to investigate the effects of these factors on actual-FiO and PEEP.
Regression formula were: (a) actual-FiO as the dependent variable: actual FiO = 2.71 + 0.78 × set-FiO + 0.17 × set-flow - 0.09 × PIF (F test, F = 3866.62, P < 0.001, R = 0.94), (b) PEEP as the dependent variable: PEEP = 1.35 + 0.15 × set-flow - 0.02 × PIF + 0.01 × tidal volume (F test, F = 4082.39, P < 0.001, R = 0.95). The following factors were found to affect actual-FiO (in descending order): set-FiO , set-flow and PIF. Tidal volume had little effect on actual-FiO . Factors which affected PEEP were (in descending order): set-flow, peak inspiratory flow and tidal volume.
在高流量鼻导管（HFNC）氧疗期间，设定流量、吸气峰流速（PIF）、潮气量和设定的吸入氧分数（FiO₂）是否会影响实际FiO₂和呼气末正压（PEEP）尚不清楚。此外，它们的影响程度也未知。
探讨设定FiO₂、设定流量、PIF和潮气量对HFNC氧疗期间实际FiO₂和PEEP的影响。
使用肺模拟模型在体外研究HFNC治疗期间可能影响FiO₂和PEEP的因素。这些因素包括设定流量（20、40、60、80和120 L/min）、PIF（40、80和120 L/min）、潮气量（400和600 mL）以及设定FiO₂（30%、50%和70%）。连续记录10次呼吸的实际FiO₂和PEEP。比较不同条件下的实际FiO₂和PEEP。进行多变量线性回归以研究这些因素对实际FiO₂和PEEP的影响。
回归公式为：（a）以实际FiO₂为因变量：实际FiO₂ = 2.71 + 0.78×设定FiO₂ + 0.17×设定流量 - 0.09×PIF（F检验，F = 3866.62，P < 0.001，R² = 0.94），（b）以PEEP为因变量：PEEP = 1.35 + 0.15×设定流量 - 0.02×PIF + 0.01×潮气量（F检验，F = 4082.39，P < 0.001，R² = 0.95）。发现以下因素会影响实际FiO₂（降序排列）：设定FiO₂、设定流量和PIF。潮气量对实际FiO₂影响很小。影响PEEP的因素（降序排列）为：设定流量、吸气峰流速和潮气量。
