Sequential application of oxygen therapy via high-flow nasal cannula and noninvasive ventilation in acute respiratory failure: An observational pilot study

Abstract

BACKGROUND: The aim of this study was to evaluate the clinical efficacy of humidified oxygen via high-flow nasal cannula (HFNC) alternating with noninvasive ventilation (NIV) in acute hypoxemic respiratory failure (AHRF). METHODS: We performed a prospective observational study in a 12-bed ICU of a university hospital. All subjects with a P aO 2 /F IO2 of ≤ 300 mm Hg with standard mask oxygen and a breathing frequency of > 30 breaths/min or signs of respiratory distress were included and treated with HFNC first and then NIV. Ventilatory parameters, blood gases, and tolerance were recorded during 2 consecutive sessions of NIV and HFNC. Outcome was assessed after continuation of this noninvasive strategy. RESULTS: Twenty-eight subjects with AHRF were studied, including 23 (82%) with ARDS. Compared with standard oxygen therapy, P aO 2 significantly increased from 83 (68–97) mm Hg to 108 (83–140) mm Hg using HFNC and to 125 (97–200) mm Hg using NIV (P