1 Division of Pediatric Critical Care Medicine, Department of Pediatrics, Seattle Children's Hospital and The University of Washington School of Medicine, FA2.112, 4800 Sandpoint Way NE, Seattle, WA, 98105, USA. elizabeth.killien@seattlechildrens.org.
2 Harborview Injury Prevention and Research Center, University of Washington, Seattle, WA, USA. elizabeth.killien@seattlechildrens.org.
3 Division of Pediatric Critical Care Medicine, Department of Pediatrics, Seattle Children's Hospital and The University of Washington School of Medicine, FA2.112, 4800 Sandpoint Way NE, Seattle, WA, 98105, USA.
4 Center for Child Health, Behavior, and Development, Seattle Children's Research Institute, Seattle, WA, USA.
5 Center for Clinical and Translational Research, Seattle Children's Research Institute, Seattle, WA, USA.