The study will be conducted by the EuSOS study group on behalf of the European Society of Intensive Care Medicine and the European Society of Anaesthesiology. National co-ordinators will lead the project within individual nations and identify participating hospitals, translate study paperwork, distribute study paperwork and ensure necessary regulatory approvals are in place. Local co-ordinators will lead in the EuSOS study in individual institutions ensuring all relevant regulatory approvals are in place and adequate training of staff. They will supervise data collection, ensure timely data return and act as guarantor for the integrity and quality of data collected.