1. Cardiothoracic Anaesthesia and Intensive Care, Manchester Royal Infirmary, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre and University of Manchester, Manchester, UK
2. Department of Anaesthesiology, Division of Critical Care Medicine, University of Florida College of Medicine, Gainesville, FL, USA
3. Department of Anaesthesia and Intensive Care, Philipps University, Marburg, Germany
4. Critical Care Research Group, Prince Charles Hospital, University of Queensland, Brisbane, Australia