Effects of Face Mask Continuous Positive Airway Pressure Vs. Noninvasive Ventilation Vs. High-flow Nasal Oxygen on Intubation-free Survival in Acute Hypoxemic Respiratory Failure: the TRIPOD Randomized Clinical Trial

Inclusion criteria

• Age≥18 yrs;
• A ratio of the partial pressure of arterial oxygen (PaO2) to the FiO2 of 300 mm Hg or less, or a ratio of pulse oximetry oxygen saturation (SpO2) to the FiO2 of 315 or less (SpO2≤97%) and the need for (1) noninvasive positive pressure ventilation with at least 5 cm H2O PEEP, or (2) high-flow nasal cannula at 30L/min or higher, or (3) standard oxygen with oxygen flow rate of at least 10 L/min;
• Sign informed consent.

Exclusion criteria

• Patients that have already received Continuous positive airway pressure, Noninvasive ventilation continuously for more than 24 hours before the screening visit.
• Previous bout of mechanical ventilation during index hospitalization.
• Exacerbation of chronic lung disease, including asthma or chronic obstructive pulmonary disease.
• Moderate to severe cardiac insufficiency (New York Heart Association class >II or left ventricular ejection fraction<50%) or cardiogenic pulmonary edema.
• Hemodynamic dysfunction, defined as vasopressor dose > 0.3 µg/kg/min of norepinephrine-equivalent to maintain systolic blood pressure > 90 mm Hg.
• Impaired consciousness with a Glasgow coma score ≤ 12.
• Patients with urgent need for intubation, including respiratory or cardiac arrest, respiratory pauses with loss of consciousness or gasping for air, severe hypoxemia defined as SpO2 lower than 90% despite maximal oxygen support.
• Patients with contraindication to NIV according to the French consensus conference, patient refusal, cardiorespiratory arrest, coma, non-drained pneumothorax, unresolved vomiting, upper airway obstruction, hematemesis or severe facial trauma, thoracic or abdominal surgery in the previous 7 days.
• A do-not-intubate order at time of inclusion.
• Pregnancy.