1 Critical Illness, Brain Dysfunction and Survivorship (CIBS) Center, Vanderbilt University Medical Center, Nashville, TN, Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, and Department of Bioengineering, Vanderbilt University, Nashville, TN Critical Illness, Brain Dysfunction and Survivorship (CIBS) Center, Vanderbilt University Medical Center, Nashville, TN, Department of Surgery, Neurosurgery and Hearing & Speech Sciences, Vanderbilt University Medical Center, Nashville, TN, and General Surgery Service, Tennessee Valley VA Healthcare System, Nashville, TN Critical Illness, Brain Dysfunction and Survivorship (CIBS) Center, Vanderbilt University Medical Center, Nashville, TN, Division of Allergy, Pulmonary and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, and Geriatric Research Education Clinical Center (VA-GRECC), Tennessee Valley VA Healthcare System, Nashville, TN.