1. From the Department of Anesthesiology (A.C.K.) and Department of Neurosurgery (N.M.), University Medical Center Utrecht, Utrecht, The Netherlands; Department of Anesthesiology, University Medical Center Nijmegen, Nijmegen, The Netherlands (G.-J.v.G., J.B., S.R.); Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland (P.E.B.); and Pain Center, Department of A