Kate Tatham BSc (Hons) MBBS MRCP FRCA PhD FFICM is Specialty Registrar in Anaesthetics and Intensive Care, Imperial School of Anaesthesia; Clinical Lecturer, Section of Anaesthetics, Pain Medicine and Intensive Care, Imperial College, London, UK Kinesh Patel BA (Hons) MBBS MRCP MD is Consultant Gastroenterologist, Chelsea and Westminster Hospital NHS Foundation Trust, London, UK