Clinically important traumatic brain injuries are rare in children.  The PECARN study provides decision rules for when to avoid unnecessarily obtaining a CT for children who have suffered head trauma.

For children < 2 years old: <0.02% risk of clinically important TBI

• Normal mental status
• No scalp hematoma, except frontal
• Loss of consciousness < 5 seconds
• No palpalble skull fracture
• Normal behavior
• Nonsevere mechanism (fall < 3ft, pedestrian struck, rollover MVC)

For children > 2 years old: <0.05% risk of clinically important TBI

• Normal mental status
• No signs of basilar skull fracture
• No loss of consciousness
• No vomiting
• No severe headache
• Nonsever mechanism (fall < 5ft, pedestrian struck, rollover MVC)

 

References

Kuppermann N, et al.  Pediatric Emergency Care Applied Research Network.  Identification of childrent at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet 2009 Oct 3;374(9696):1160-70.