Study population
Subjects were eligible for participation if: (1) aged ≥ 18 years; (2) scheduled for elective cardiac surgery; and (3) expected to require at least two hours of ventilation after arrival in the ICU, e.g., patients scheduled for open valve surgery, aortic surgery or on–pump coronary artery bypass grafting. Exclusion criteria were previous inclusion in this study, and participation in another intervention that could influence ventilator settings and ventilation parameters. We also excluded subjects with confirmed or suspected pregnancy, and subjects that were expected to die in the first hours after surgery.