Failure Prediction of High-Flow Nasal Cannula at the Conventional Oxygen Therapy Phase in the Emergency Department

The use of high-flow nasal cannula (HFNC) in patients with acute hypoxemic respiratory failure has been increasing in the emergency department (ED). However, studies are lacking on the prediction of HFNC failure before therapy initiation in the ED. We investigated whether the existing indices, such as the ratio of pulse oximetry oxygen saturation/fraction of inspired oxygen to respiratory rate (ROX) and ratio of ROX index to heart rate (ROX-HR), can accurately predict HFNC failure at the conventional oxygen therapy phase in the ED.