1 Nuffield Department of Clinical Neurosciences, Jesus College, University of Oxford and Coventry University, United Kingdom. Electronic address: arun.joseph@ndcn.ox.ac.uk.
2 Centre for Care Excellence, University Hospitals Coventry & Warwickshire NHS Trust, Clifford Bridge Road, Coventry CV2 2DX, United Kingdom.
3 King's College London, St Thomas Hospital, London, United Kingdom; Provincial Centre of Weaning Excellence at the Michal Garron Hospital, Toronto, Canada.