Ronald S Litman1, Girish P Joshi. 1. From the Department of Anesthesiology and Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, and Department of Anesthesiology and Critical Care, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania (R.S.L.); and Anesthesiology and Pain Management, University of Texas Southwestern Medical Center, Dallas, Texas (G.P.J.).