Multicenter external validation of the Pediatric Emergency Care Applied Research Network rule to identify children at very low risk for intra-abdominal injury requiring acute intervention

BACKGROUND A clinical prediction rule has been published by the Pediatric Emergency Care Applied Research Network (PECARN) to identify children at very low risk of intra-abdominal injury requiring acute intervention (IAI-intervention) following blunt abdominal trauma in which computed tomography scan of the abdomen could be avoided. This study aims to assess the external validity of the PECARN prediction rule for IAI-intervention and determine its accuracy for identifying all patients with intra-abdominal injuries following blunt abdominal trauma, including those who did not require acute interventions. METHODS Data were collected prospectively from 14 trauma centers for 2,188 children younger than 16 years who presented following blunt abdominal trauma over a 1-year period. We then retrospectively applied the PECARN prediction rule to this new cohort to risk stratify the patients for intra-abdominal injury (IAI) and IAI-intervention. RESULTS A total of 2,188 children with a mean (SD) age of 7.8 (4.6) years were included. The PECARN prediction rule identified 60 of 62 patients with IAI-intervention with a sensitivity of 96.8%, specificity of 46.6%, and a negative predictive value (NPV) of 99.8%. The PECARN prediction rule identified 227 of 261 patients with any IAI with a sensitivity of 86.6%, specificity of 49.7%, and an NPV of 96.5%. The most missed injury by the PECARN rule was liver laceration (n = 22). In addition, 34 of 35 patients with an IAI not predicted by the PECARN rule had an abnormal laboratory value or x-ray finding. CONCLUSION Although the PECARN prediction rule has excellent NPV for identifying patients with intra-abdominal injuries needing an acute intervention, it fails to detect some children with clinically impactful intra-abdominal injuries that required additional management. The addition of trauma bay laboratories and chest x-ray should be used to predict patients at very low risk for all IAI.