Noninvasive Ventilation Facemasks Favoring Carbon Dioxide Washout

Exclusion Criteria

• •Respiratory rate \< 12 bpm;
• •Immediate need for intubation;
• •Haemodynamic instability (Systolic blood pressure \<90 mmHg or mean arterial pressure \<65 mmHg) and/or lactic acidosis (lactate \>5 mmol/L) and/or clinically diagnosed shock;
• •Metabolic Acidosis;
• •Recent head surgery or anatomy that prevent the application of facemasks;
• •Any contraindications to oesophageal balloon insertion and/or electrical impedance tomography (EIT) belt placement.
• •Any contraindications to facemask noninvasive ventilation.