1 Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of California San Diego, La Jolla, California.
2 Corresponding author: Matthew P. Light, MD, Division of Pulmonary, Critical Care and Sleep Medicine, University of California San Diego, 9300 Campus Point Drive #7381, La Jolla, CA 92037 (mlight@health.ucsd.edu).
3 Pulmonary Critical Care Section, Veterans Affairs San Diego Healthcare System, La Jolla, California.
4 Division of Neurocritical Care, Department of Neurosciences, University of California San Diego, La Jolla, California.