Level 1: Likely reliable evidence
CT is often performed on children with head trauma to diagnose clinically important traumatic brain injuries. Attempts have been made to develop criteria that might safely avoid unnecessary procedures. The Pediatric Emergency Care Applied Research Network (PECARN) study has now developed a prediction rule that identifies children who are at very low risk of clinically important injury and for whom CT imaging may be avoided (Lancet. 2009;374:1160-1170). The derivation and validation cohorts included 42,412 children younger than 18 years (10,718 children younger than 2 years) presenting to emergency departments within 24 hours of head trauma with Glasgow Coma Scale scores of 14-15. CT was performed in 35% of the children at the discretion of the attending physician, and clinically important trauma was identified in 0.32% of them.
Based on the results of this study, CT can safely be withheld for children 2 years and older who meet all of the following criteria: normal mental status, no loss of consciousness, no vomiting, nonsevere injury mechanism, no signs of basilar skull fracture, and no severe headache. CT can be withheld in children younger than 2 years if they meet all of the following criteria: normal mental status, no scalp hematoma except frontal, loss of consciousness lasting 0-5 seconds, nonsevere injury mechanism, no palpable skull fracture, and acting normally according to the parents. The rule had sensitivity of 97%-100%, specificity of 54%-60%, and negative predictive value of 99%-100%. If children do not meet the criteria, then clinical judgment taking into account mechanism of injury and findings during the examination will help decide who needs CT evaluation.