Age

18–any

Sex

ALL

Healthy volunteers

Not accepted

Age \> 18 years
Acute hypoxemic respiratory failure (AHRF) with a PaO2/FiO2-ratio ≤ 200
Patient on invasive assisted mechanical ventilation in pressure support mode exhibiting valid inspiratory efforts (occlusion pressure \> 5 cmH2O).

Pre-existent neuromuscular disease
History of chronic respiratory failure requiring long-term oxygen therapy
Muscle paralysis
Pneumothorax
Contra-indication to EIT monitoring (e.g. burns, pacemaker, thoracic wounds limiting electrode placement)
Contra-indications for EAdi or oesophageal balloon catheter placement (e.g. history of gastric bypass surgery, gastro-oesophageal junction surgery, oesophageal stricture, recent upper gastrointestinal hemorrhage or known/suspected varices).

PEEP-induced Effects on Respiratory dRivE and EFfort