Comparison of the effects of 4 ventilators dedicated to NIV (2 home ventilators and 2 ventilators designed for NIV) on patient-ventilator synchrony and comfort in patients admitted in the intensive care unit for respiratory failure and treated with NIV.

Inclusion Criteria:

• respiratory failure

Exclusion Criteria:

• Severe hypoxemia requiring an FiO2 > 0.6
• Hemodynamic instability : defined as a variation of > 20% in mean arterial pressure (MAP) and heart rate (HR) during the previous 2 hours; the need for high doses of catecholamines (namely > 0.5 mcg/kg/min) and/or the need of major volume resuscitation (more than 2 liters of fluids in 2 hours)
• Impaired consciousness or absence of patient cooperation;
• Facial or laryngeal lesions contraindicating the use of NIV;
• Poor short term prognosis.
• Age < 18 years old