ABSTRACT
Acute respiratory failure (ARF) is one primary cause of intensive care unit (ICU) admittance, which is usually treated with intubation and mechanical ventilation in order to maintain a necessary ventilation and oxygenation function. After the remove of trachea tube, available oxygenation supports include nasal cannula, venturi mask, non-invasive ventilator and high flow nasal cannula (HFNC). In this articlewe reviewed the physiological mechanism related to HFNC therapy and trails about the application of HFNC in extubated patients. HFNC can provide well heated and humidified high flow gas with a high concentration of oxygen, which can improve the oxygenation and degree of comfort of patients after extubation. Furthermore, HFNC can improve the prognosis of these patients. However, HFNC has little influence on non-ventilation related factor and severe dysfunction of ventilation, so its indication and risk factor of treatment failure should be further evaluated with randomize controlled trials.