1. Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, United States
2. Department of Neurology, Washington Veterans Affairs Medical Center, Washington, DC, United States
3. Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
4. Department of Neurology, George Washington University School of Medicine, Washington, DC, United States
5. Departments of Anesthesiology and Critical Care Medicine, Neurology, Physical Medicine and Rehabilitation and Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine, Baltimore, MD, United States
6. Department of Physical Medicine and Rehabilitation and Anesthesiology, Walter Reed National Military Medical Center, Uniformed Services University of the Health Sciences, Bethesda, MD, United States