METHODS: This is a retrospective cohort analysis using the National Trauma Data Bank registry 2009. Children aged 0 to 15 years were classified by injury pattern sustained during trauma using discharge diagnosis International Classification of Diseases, Ninth Revision, codes into isolated head, hemorrhagic, spinal cord, or other injury type. The primary outcome was hypotension for age at arrival to the emergency department. Risk of hypotension was estimated and compared by injury pattern using absolute and relative risks (RRs) stratified by age group (0-4 years, 5-11 years, 12-15 years).