title: Isolated loss of consciousness in children with minor blunt head trauma.
abstract: OBJECTIVE
  A history of loss of consciousness (LOC) is frequently a driving factor for computed tomography use in the emergency department evaluation of children with blunt head trauma. Computed tomography carries a nonnegligible risk for lethal radiation-induced malignancy. The Pediatric Emergency Care Applied Research Network (PECARN) derived 2 age-specific prediction rules with 6 variables for clinically important traumatic brain injury (ciTBI), which included LOC as one of the risk factors.
  
  
  OBJECTIVE
  To determine the risk for ciTBIs in children with isolated LOC.
  
  
  METHODS
  This was a planned secondary analysis of a large prospective multicenter cohort study. The study included 42 ,412 children aged 0 to 18 years with blunt head trauma and Glasgow Coma Scale scores of 14 and 15 evaluated in 25 emergency departments from 2004-2006.
  
  
  METHODS
  A history of LOC after minor blunt head trauma.
  
  
  METHODS
  The main outcome measures were ciTBIs (resulting in death, neurosurgery, intubation for >24 hours, or hospitalization for ≥2 nights) and a comparison of the rates of ciTBIs in children with no LOC, any LOC, and isolated LOC (ie, with no other PECARN ciTBI predictors).
  
  
  RESULTS
  A total of 42 412 children were enrolled in the parent study, with 40 693 remaining in the current analysis after exclusions. Of these, LOC occurred in 15.4% (6286 children). The prevalence of ciTBI with any history of LOC was 2.5% and for no history of LOC was 0.5% (difference, 2.0%; 95% CI, 1.7-2.5). The ciTBI rate in children with isolated LOC, with no other PECARN predictors, was 0.5% (95% CI, 0.2-0.8; 13 of 2780). When comparing children who have isolated LOC with those who have LOC and other PECARN predictors, the risk ratio for ciTBI in children younger than 2 years was 0.13 (95% CI, 0.005-0.72) and for children 2 years or older was 0.10 (95% CI, 0.06-0.19).
  
  
  CONCLUSIONS
  Children with minor blunt head trauma presenting to the emergency department with isolated LOC are at very low risk for ciTBI and do not routinely require computed tomographic evaluation.
authors.affiliation: Division of Emergency Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: Lois K
authors.initials: LK
authors.lastname: Lee
authors.affiliation: Department of Emergency Medicine, Howard County General Hospital, Columbia, Maryland.
authors.forename: David
authors.initials: D
authors.lastname: Monroe
authors.affiliation: Departments of Emergency Medicine and Pediatrics, Newark Beth Israel Medical Center, Newark, New Jersey.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Bachman
authors.affiliation: Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio.
authors.forename: Todd F
authors.initials: TF
authors.lastname: Glass
authors.affiliation: Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan.
authors.forename: Prashant V
authors.initials: PV
authors.lastname: Mahajan
authors.affiliation: Department of Surgery, Columbia University Medical Center at Harlem Hospital, New York, New York.
authors.forename: Arthur
authors.initials: A
authors.lastname: Cooper
authors.affiliation: Department of Emergency Medicine, University of Michigan School of Medicine, Ann Arbor.
authors.forename: Rachel M
authors.initials: RM
authors.lastname: Stanley
authors.affiliation: Department of Pediatrics, University of Utah, Salt Lake City.
authors.forename: Michelle
authors.initials: M
authors.lastname: Miskin
authors.affiliation: Division of Emergency Medicine, Morgan Stanley Children's Hospital, Columbia University College of Physicians and Surgeons, New York, New York.
authors.forename: Peter S
authors.initials: PS
authors.lastname: Dayan
authors.affiliation: Department of Emergency Medicine, University of California, Davis School of Medicine.
authors.forename: James F
authors.initials: JF
authors.lastname: Holmes
authors.affiliation: Department of Emergency Medicine, University of California, Davis School of Medicine11Department of Pediatrics, University of California, Davis School of Medicine.
authors.forename: Nathan
authors.initials: N
authors.lastname: Kuppermann
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004636:Emergency Service, Hospital; D005260:Female; D016489:Head Injuries, Closed / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D014474:Unconsciousness / Q000150:complications* / Q000453:epidemiology