title: Injury patterns associated with hypotension in pediatric trauma patients: A national trauma database review.
abstract: BACKGROUND
  Hypotension after trauma is most commonly assumed to be hemorrhagic, or hypovolemic, in origin. However, hypotension may occur in pediatric patients with isolated head injury, challenging accepted tenets of trauma care. We sought to quantify the contribution of head injury to the development of hypotension after pediatric trauma.
  
  
  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).
  
  
  RESULTS
  Rates of hypotension ranged from 1.8% to 2.3% by age, with the highest incidence in the 12- to 15-year group. The RR of hypotension from isolated head injury (RR, 2.5; 95% confidence interval, 2.0-3.2 vs. other) was not significantly different from the RR for hemorrhagic injury (RR, 2.7; 95% confidence interval, 2.1-3.5 vs. other) in the 0- to 4-year-old group. For the older age groups, the RR of hypotension from isolated head injury was significantly lower than from hemorrhagic injury.
  
  
  CONCLUSIONS
  Hypotension occurs after isolated head injury in children, and the risk of hypotension is as great as hemorrhagic injuries in children aged 0 to 4 years. This finding should now lead us to confirm whether a cause-effect relationship exists and, if so, isolate the responsible mechanism. In turn, this could reveal an opportunity to tailor treatments to address the underlying mechanism for hypotension in these children.
  
  
  METHODS
  Prognostic and epidemiologic study, level III.
authors.affiliation: From the Departments of Pediatrics and Emergency Medicine (A.R.G.), General Surgery, Division of Surgical Sciences (D.I.D.), Biostatistical Sciences (J.A.T.), Emergency Medicine (C.D.M.), and General Surgery, Section of Pediatric Surgery (J.P.), Wake Forest University School of Medicine, Winston-Salem, North Carolina.
authors.forename: Alison R
authors.initials: AR
authors.lastname: Gardner
authors.forename: Debra I
authors.initials: DI
authors.lastname: Diz
authors.forename: Janet A
authors.initials: JA
authors.lastname: Tooze
authors.forename: Chadwick D
authors.initials: CD
authors.lastname: Miller
authors.forename: John
authors.initials: J
authors.lastname: Petty
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D006259:Craniocerebral Trauma / Q000150:complications* / Q000473:pathology; D005260:Female; D015600:Glasgow Coma Scale; D006470:Hemorrhage / Q000150:complications* / Q000473:pathology; D006801:Humans; D007022:Hypotension / Q000453:epidemiology* / Q000473:pathology* / Q000628:therapy; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D015601:Injury Severity Score; D008297:Male; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D013119:Spinal Cord Injuries / Q000150:complications* / Q000473:pathology; D014193:Trauma Centers; D014481:United States / Q000453:epidemiology