Patients scheduled for ICU admission after elective surgery, will be recruited at the outpatient clinic (anaesthesiology or cardiac surgery) (Figure 1). Patients with a non-scheduled admission will be recruited at the ICU. Patients will receive information by ICU nurses and intensivists regarding the aim, content and relevance of the study, and will be asked for participation. Informed consent is asked for the questionnaires, data from the patients' individual medical record and data from their health insurance company. In case patients are unable to give consent, their legal representative will be asked.