1 Department of Anesthesiology, Duke University School of Medicine, Duke University Medical Center, Durham, North Carolina.
2 Department of Anesthesiology, Duke University School of Medicine, Duke University Medical Center, Durham Veterans Health Administration, Durham, North Carolina.
3 Yuriy S. Bronshteyn, M.D., F.A.S.E.; Department of Anesthesiology, Duke University School of Medicine, Duke University Medical Center, Durham Veterans Health Administration, Durham, North Carolina.