1. From the Department of Laboratories (G.S.B.), Denver Health Medical Center, Denver, Colo; the Department of Pediatrics (A.E.O., P.A.W.A.), Duke University Medical Center, Durham, NC; the Department of Anesthesiology (P.D.A.), Brigham and Women’s Hospital, Boston, Mass; and the Department of Pathology (G.S.B., D.L.C., J.H.L.), Division of Laboratory Medicine, Washington University, St Louis, Mo.