1. From the Division of Neurosciences Critical Care (L.C.), The Johns Hopkins Hospital, Baltimore; Division of Brain Injury Outcomes, Department of Neurology (W.D.Z., D.F.H.) and Division of Neurosciences Critical Care Medicine, Departments of Neurology, Neurosurgery, and Anesthesiology and Critical Care Medicine (W.C.Z., V.S.), Johns Hopkins University School of Medicine, Baltimore, MD.