1 From the Department of Anesthesiology, Vanderbilt University Medical Center; the Department of Perioperative and Critical Care Services, Vanderbilt University Adult Hospital; the Department of Anesthesiology, Surgery and Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, Tennessee (W.S.S.) Anesthesiology and Perioperative Medicine, Mayo Clinic College of Medicine, Jacksonville, Florida (S.J.B.).