[1] Royal Papworth Hosp, Dept Anaesthesia & Intens Care, Cambridge, England
[2] Assoc Anaesthetists Working Party, London, England
[3] James Cook Univ Hosp, Dept Anaesthesia, Middlesbrough, Cleveland, England
[4] Royal United Hosp NHS Trust, Bath, Avon, England
[5] Royal Gwent Hosp, Dept Anaesthesia, Newport, Gwent, Wales
[6] Royal Derby Hosp, Derby, England
[7] Royal Infirm Edinburgh NHS Trust, Dept Anaesthesia, Edinburgh, Midlothian, Scotland
[8] Univ Oxford, Oxford, England
[9] Royal Coll Anaesthetists, London, England
[10] Guys & St Thomas NHS Fdn Trust, Dept Anaesthesia, London, England
[11] Reg Anaesthesia UK RA UK, London, England
[12] Ninewells Hosp, Dept Anaesthesia, Dundee, Scotland
[13] Queen Elizabeth Hosp, Dept Anaesthesia & Crit Care, Kings Lynn, England