Recently, Hamilton Medical has introduced the new mechanical ventilation mode "INTELLiVENT-ASV". This is a fully closed ventilation mode that can automatically adjust the ventilation settings based on the measured End tidal CO2 (ETCO2) and the measured saturation (SpO2) in both passive and active ventilated patients. Current literature has shown that this mode is safe to use in patients admitted on the intensive care unit. A pilot study in the Catharina Hospital Eindhoven confirmed that in postoperative low risk patients on the intensive care unit INTELLiVENT-ASV is safe. Compared to continuous mandatory or pressure controlled ventilation with pressure support (conventional mechanical ventilation), INTELLiVENT-ASV is even as effective as conventional mechanical ventilation, with a significantly reduced number of interactions with the ventilator. However, available research about the effectiveness of INTELLiVENT-ASV in postoperative high risk patients is lacking. Also the knowledge about the user-friendliness of the above modes of mechanical ventilation for the users is lacking.