1. Division of Surgery and Interventional Science University College London London UK
2. Department of Anaesthesia James Cook University Hospital Middlesbrough UK
3. Department of Anaesthesia Severn Deanery Bristol UK
4. Department of Anaesthesia Royal United Hospitals Bath NHS Foundation Trust Bath UK
5. Department of Anaesthesia and Intensive Care Medicine Royal United Hospitals Bath NHS Foundation Trust Bath UK
6. Anaesthesia University of Bristol Bristol UK
7. Department of Anaesthesia and Intensive Care Medicine Southmead Hospital Bristol UK