Clinical Research Directory

Inclusion Criteria: * Major patient admitted to the intensive care unit or continuous care unit for de novo hypoxaemic acute respiratory failure (with a PaO2/FiO2 ratio \<300 mmHg) * Treated with HDNO for at least 24 hours in an intensive care unit or continuous care unit * Treated with HFNO with a flow rate ≥ 50L/min and inspired oxygen fraction (FiO2) ≥ 0.5, at inclusion * With a ROX index (SpO2/FiO2/Respiratory Rate) stable or improving in the 6 hours prior to inclusion and greater than 4.88 (the patient must not be in a worsening phase). * Had a blood gas test under HFNO within 24 hours of inclusion * Participant covered by or entitled to social security * Informed consent signed by the patient or its relatives if the patient is incapable; this consent must then be confirmed by the patient as soon as possible Exclusion Criteria: * Presence of a patient included in the study and not weaned off HFNO in the sector managed by the nurse of the patient assessed for eligibility * Concomitant non-invasive ventilation treatment * Use of HFNO within 7 days of extubation * Chronic obstructive pulmonary disease (Gold grade 3 or 4) * Cardiogenic acute pulmonary oedema as the main cause of acute respiratory failure * Diffuse interstitial lung disease as a medical history * Patient with long-term non-invasive ventilation with external positive pressure * Patient on long-term oxygen therapy at home * Pregnant women, women in labour and breastfeeding mothers * Persons deprived of their liberty by a judicial or administrative decision, persons hospitalised without consent and persons admitted to a health or social establishment for purposes other than research. * Minor * Adult subject to a legal protection measure (guardianship, curators, person under court protection) * Patient with a medical decision not to intubate * Patients already included in the study, neither for the same stay if they were to present the inclusion criteria again, nor for subsequent stays