1 Department of Anesthesiology & Pain Medicine, University of Washington, Seattle, WA, USA ; Harborview Injury Prevention and Research Center, Washington, Seattle, WA, USA.
2 Harborview Injury Prevention and Research Center, Washington, Seattle, WA, USA ; Departments of Pediatrics, Neurological Surgery and Radiology, University of Washington, Seattle, WA, USA.
3 Harborview Injury Prevention and Research Center, Washington, Seattle, WA, USA ; Departments of Surgery and Epidemiology, University of Washington, Seattle, WA, USA.