Use of Nasal High Flow Oxygen During Breaks of Non-invasive Ventilation for Patients With Hypercapnic Respiratory Failure

Exclusion Criteria

• •Contraindications to NIV;
• •Purely restrictive lung disease (thoracic deformity, neuro-muscular pathology) and pure obstructive sleep apnoea (without spirometric disturbance or daytime gas anomaly)
• •Immediate need for intubation (respiratory or cardiac arrest);
• •Persistent hemodynamic instability (use of vasopressors for \> 1 hour);
• •Multiple organ failure (score SOFA\>6);
• •NIV treatement for \>3 consecutive hours (without any interruption) before admission to ICU, intermediate care, or respiratory care unit and before randomization;
• •Anticipated difficulties to conduct NIV (facial trauma or deformation, edentulous patient);
• •End stage chronic respiratory insufficiency (defined as use of NIV at home or CPAP treatment at home and life expectancy below 6 month);
• •Non-treated pneumothorax;
• •Impossibility to perform subjective assessment of dyspnea and comfort (cognitive impairment);
• •Patient under guardianship or trusteeship;
• •Pregnancy/breastfeeding;
• •Decision to withhold or to withdraw life-sustaining treatments (including intubation)
• •Moribund state
• •Current participation in another clinical trial with an endpoint related to NIV.
• •No affiliation to social security (beneficial or assignee);
• •Refusal to participate to the study (patient or legal representative or family member or close relative if present