- Hypersensitivity to the active substance or to any of the excipients - Pregnancy or breastfeeding woman - Known Hepatic failure (PT <50%, Factor V < 50%) - Known Plasma total bilirubin > 21 µmol/L during hospitalization - Lactate level > 4 mmol/L - Known pulmonary hypertension or right ventricular dysfunction - Diagnosis of pulmonary embolism during the current hospitalization or on-going anticoagulant therapy at curative dose for thromboembolism when hospitalized - PaCO2 of >45 mmHg - Exacerbation of asthma or chronic respiratory failure - Cardiogenic pulmonary edema - Systolic blood pressure of 90 mmHg or less, or use of vasopressor - Urgent need for endotracheal intubation at the discretion of the treating physician - Do-not-intubate order or estimated life expectancy less than 6 months - Participation in another interventional research

- Hypersensitivity to the active substance or to any of the excipients - Pregnancy or breastfeeding woman - Known Hepatic failure (PT <50%, Factor V < 50%) - Known Plasma total bilirubin > 21 µmol/L during hospitalization - Lactate level > 4 mmol/L - Known pulmonary hypertension or right ventricular dysfunction - Diagnosis of pulmonary embolism during the current hospitalization or on-going anticoagulant therapy at curative dose for thromboembolism when hospitalized - PaCO2 of >45 mmHg - Exacerbation of asthma or chronic respiratory failure - Cardiogenic pulmonary edema - Systolic blood pressure of 90 mmHg or less, or use of vasopressor - Urgent need for endotracheal intubation at the discretion of the treating physician - Do-not-intubate order or estimated life expectancy less than 6 months - Participation in another interventional research