Author/Authors :
Zhou, Yuyan Department of Respiratory and Critical Care Medicine - West China Hospital - Sichuan University, Chengdu, Sichuan, China , Ni, Zhong Department of Respiratory and Critical Care Medicine - West China Hospital - Sichuan University, Chengdu, Sichuan, China , Ni, Yuenan Department of Respiratory and Critical Care Medicine - West China Hospital - Sichuan University, Chengdu, Sichuan, China , Liang, Binmiao Department of Respiratory and Critical Care Medicine - West China Hospital - Sichuan University, Chengdu, Sichuan, China , Liang, Zongan Department of Respiratory and Critical Care Medicine - West China Hospital - Sichuan University, Chengdu, Sichuan, China
Abstract :
Background. High-flow nasal cannula (HFNC) oxygen therapy has been recommended for use in coronavirus disease 2019
(COVID-19) patients with acute respiratory failure and many other clinical conditions. HFNC devices produced by different
manufacturers may have varied performance. Whether there is a difference in these devices and the extent of the differences in
performance remain unknown. Methods. Four HFNC devices (AIRVO 2, TNI softFlow 50, HUMID-BH, and OH-70C) and a
ventilator with an HFNC module (bellavista 1000) were evaluated.The flow was set at 20, 25, 30, 35, 40, 45, 50, 60, 70, and 80 L/
min, and the FiO2 was set at 21%, 26%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, and 90%. Then, one side of the cannulas was
clipped to simulate the compression, bending, or blocking of the nasal cannulas. The flow and FiO2 of the delivered gas were
recorded and compared among settings and devices. Results. The actual-flow and actual-FiO2 delivered by different settings and
devices varied. AIRVO 2 had superior performance in flow and FiO2 accuracy. bellavista 1000 and OH-70C had good performance
in the accuracy of actual-flows and actual-FiO2, respectively. bellavista 1000 and HUMID-BH had a larger flow range from 10 to
80 L/min, but only bellavista 1000 could provide a stable flow with an excessive resistance up to 60 L/min. TNI softFlow 50 had the
best flow compensation and could provide sufficient flow with excessive resistance at 20–50 L/min. Conclusions. The variation in
flow, FiO2 settings, and devices could influence the actual-flow and actual-FiO2 delivered. AIRVO 2 and OH-70C showed better
FiO2 accuracy. TNI softFlow 50, bellavista 1000, and HUMID-BH could lower the risk of insufficient flow support due to
accidental compression or blocking of the cannulas. In addition, ventilators with HFNC modules provided comparable flow and
FiO2 and could be an alternative to standalone HFNC devices.
