PECARN Head CT Rule

The PECARN head injury rule was derived in a population of patients younger than 18 years old with blunt head injury. 42412 patients were included in the study population with a goal of identifying patients at very low risk of clinically important traumatic brain injury (ciTBI) by history and exam criteria, obviating the need for CT imaging. 

Child <2 yo

High risk criteria: CT recommended if any single criterion present. 4.4% risk ciTBI

• GCS = 14
• Altered mental status
• Palpable skull fracture

Low risk criteria: Observation vs CT recommended if any single criterion present. 0.9% risk ciTBI

• Non-frontal hematoma
• Not acting normally per parent
• Severe mechanism
  • Fall >3 ft
  • MVC with ejection, death of passenger, or rollover
  • Unhelemeted pedestrian or bicyclist struck by vehicle
  • Head struck by high impact object

Avoid CT if no criteria present. <0.02% risk ciTBI

Child >2 yo

High risk criteria: CT recommended if any single criterion present 4.3% risk ciTBI

• GCS = 14
• AMS
• Signs of basilar skull fracture

Low risk criteria: Observation vs CT recommended if any single criterion present 0.9% risk ciTBI

• History of LOC
• History of vomiting
• Severe headache
• Severe mechanism
  • Fall >5 ft
  • MVC with ejection, death of passenger, or rollover
  • Unhelemeted pedestrian or bicyclist struck by vehicle
  • Head struck by high impact object

Avoid CT if no criteria present. <0.05% risk ciTBI 

Results: 

• 96.8% sensitivity > 2yo
• 100%  sensitivity < 2yo

Definitions and caveats:

• The rule is unidirectional. If a child meets none of the criteria, a head CT can be safely avoided. However, if a child meets one or more criteria, that does not automatically mandate a head CT. There are low and high risk criteria that can help with this decision:
• Children with GCS <14 were excluded because the risk of TBI in CT is 20% and outweighs any risk of radiation exposure.
• Overall prevalence of TBI was 5.2% ¹
• Overall prevalence of ciTBI was 0.9% ¹
• “Estimated lifetime cancer mortality risks attributable to the radiation exposure from a CT in a 1-year-old are 0.18% (abdominal) and 0.07% (head)-an order of magnitude higher than for adults-although those figures still represent a small increase in cancer mortality over the natural background rate.” ²

MD Calc link

Further Reading :

Optimizing Imaging in the Pediatric Trauma Patient, Part 1: Head and Neck Trauma – Trauma EXTRA Supplement (Trauma CME)This Pediatric Trauma EXTRA CME supplement (free to Pediatric Emergency Medicine Practice subscribers) reviews imaging recommendations and interpretations in

Emergency Department Assessment and Management of Pediatric Acute Mild Traumatic Brain Injury and Concussion (Trauma CME)This issue reviews the most recent literature on mTBI and concussion and provides recommendations for the evaluation, diagnosis, and treatment of mTBI and

Accidental Trauma of Infancy: Emergency Department Evaluation and Management – Trauma EXTRA Supplement (Trauma CME)This Pediatric Trauma EXTRA CME supplement (free to Pediatric Emergency Medicine Practice subscribers) reviews the management of infants with traumatic injuries.

Management of Multiply Injured Pediatric Trauma Patients in the Emergency DepartmentWhen a child with multiple traumatic injuries presents to the ED, a systematic approach to evaluation and management will ensure that no major injuries are missed.

Additional References: 

• Kuppermann N, Holmes JF, Dayan PS, Hoyle JD Jr, Atabaki SM, Holubkov R, Nadel FM, Monroe D, Stanley RM, Borgialli DA, Badawy MK, Schunk JE, Quayle KS, Mahajan P, Lichenstein R, Lillis KA, Tunik MG, Jacobs ES, Callahan JM, Gorelick MH, Glass TF, Lee LK, Bachman MC, Cooper A, Powell EC, Gerardi MJ, Melville KA, Muizelaar JP, Wisner DH, Zuspan SJ, Dean JM, Wootton-Gorges SL; Pediatric Emergency Care Applied Research Network (PECARN). Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet. 2009 Oct 3;374(9696):1160-70. doi: 10.1016/S0140-6736(09)61558-0. Epub 2009 Sep 14. Erratum in: Lancet. 2014 Jan 25;383(9914):308. PMID: 19758692.
• Brenner D, Elliston C, Hall E, Berdon W. Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR Am J Roentgenol. 2001;176(2):289-96. PubMed
• PECARN Pediatric Head Trauma: Official Visual Decision Aid for Clinicians PDF
• Pediatric Emergency Care Applied Research Network – PECARN

Last Updated on January 25, 2023