1. Academic Neurosurgical Unit, University of Cambridge Clinical School, Cambridge, United Kingdom.
2. Department of Neurosurgery, University Hospital of Basel, Basel, Switzerland.
3. Department of Anaesthesia and Critical Care, Fondazione Policlinico San Matteo, Pavia, Italy.
4. Department of Anaesthetics, University of Cambridge Clinical School, Cambridge, United Kingdom.
5. Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Hospital, Baltimore, Maryland.