[1] Cleveland Clin, Outcomes Res Dept, Inst Anesthesiol, Cleveland, OH 44106 USA
[2] Istanbul Univ Cerrahpasa, Dept Anesthesiol & Reanimat, Cerrahpasa Med Fac, Istanbul, Turkey
[3] Univ Hosp AOU Careggi, Dept Clin & Expt Med, Florence, Italy
[4] Massachusetts Gen Hosp, Dept Anesthesia Crit Care & Pain Med, Boston, MA 02114 USA
[5] Univ Autonoma Madrid, Dept Anat Histol & Neurosci, Madrid, Spain
[6] Hosp Infanta Leonor, Dept Anesthesia, Madrid, Spain
[7] Hosp Univ Mostoles, Dept Anesthesia, Madrid, Spain