[1] Karolinska Inst, Dept Physiol & Pharmacol, S-17177 Stockholm, Sweden
[2] Karolinska Hosp & Inst, Dept Clin Neurosci, Neurosurg Sect, Stockholm, Sweden
[3] Mil Teaching Hosp, Serv Reanimat, Toulon, France
[4] Uppsala Univ, Dept Neurosci, Neurosurg Sect, Uppsala, Sweden
[5] Addenbrookes Hosp, Acad Dept Neurosurg, Cambridge, England
[6] Univ Lund Hosp, Dept Clin Neurosci, S-22185 Lund, Sweden
[7] Baylor Coll Med, Dept Neurosurg, Houston, TX 77030 USA
[8] Vall Hebron Univ Hosp, Dept Neurosurg, Barcelona, Spain
[9] Natl Hosp Neurol & Neurosurg, Dept Neuroanaesthesia, London WC1N 3BG, England
[10] Osped Maggiore, Policlin IRCCS, Dept Anaesthesia & Intens Care, Milan, Italy
[11] Univ Klinikum Heidelberg, Neurochirurg Klin & Poliklin, Heidelberg, Germany
[12] Univ Copenhagen Hosp, Dept Neuroanaesthesia, DK-2100 Copenhagen, Denmark