PECARN Pediatric Intra-Abdominal Injury (IAI) Algorithm
Why Use
May help rule out intra-abdominal injury from blunt torso trauma requiring acute intervention, with 97% sensitivity and 99.9% negative predictive value. May decrease use of CT scan to assess for intra-abdominal injury as very low risk children may not need a scan. Reducing use of CT scans in pediatric abdominal trauma can decrease risk of malignancy later in life, as exposure to ionizing radiation during childhood is associated with increased risk of malignancies over a lifetime. Does not require laboratory or ultrasonographic information. Found to be more sensitive than unstructured clinical suspicion in one study ( Mahajan 2015 ).
When to Use
Patients <18 years old presenting with blunt abdominal trauma within 24 hours of injury. Do not use in patients with any of the following characteristics: Penetrating trauma. Pre-existing neurologic disorders impeding a reliable exam. Pregnancy. Transfer from another hospital where abdominal CT or diagnostic peritoneal lavage was already performed.
Pearls / Pitfalls
Uses history and physical only (no labs or imaging). Aspects of history may be difficult or unreliable in nonverbal or young children. Patients with altered mental status or findings of abdominal wall trauma (bruising, abrasions, seat belt sign) are at highest risk for intra-abdominal injury. Mandatory CT was not performed in all study patients for ethical reasons, so minor clinically silent injuries may be missed. Six patients with IAI requiring intervention who were misclassified as very low risk, with the following mechanisms of injury: motor vehicle collision (4 patients), non-accidental trauma (1 patient), child struck by vehicle (1 patient). All six had hemoperitoneum, four had splenic injury, two had kidney injury, two had intestinal injury, and one had liver injury. Of the six injuries misclassified as low risk, five had laboratory abnormalities that implied intra-abdominal injury (hematuria, elevated liver enzymes). Five of the six missed patients also had either distracting injury or alcohol intoxication.
Management
Patients deemed very low risk for intra-abdominal injury requiring acute intervention may avoid CT abdomen, unless clinical suspicion exists for significant intra-abdominal injury. Take into consideration the resources at hand as well as the patient’s ability to achieve close follow-up or easily return to the hospital when planning work-up and disposition. One or more positive predictors does not necessitate a CT scan. Other methods of imaging or laboratory work-up can assist in identifying IAI requiring intervention (e.g. FAST, liver enzymes, lipase, UA, or other forms of imaging based on clinical stability and resources available). Observation with serial abdominal exams may be an option in clinically stable patients.
Critical Actions
As always, use ABCs and intervene to stabilize the patient with blunt abdominal trauma before making decisions regarding imaging.
Advice
Should not be used to dictate whether a patient needs a CT or not; it is purely to identify patients at very low risk for an injury requiring acute intervention. The risk percentage estimated by this tool can aid in shared decision making between the patient, their family, and the treating clinician on whether to pursue imaging with ionizing radiation. For children, the lifetime risk of developing radiation-induced fatal cancer increases by up to 0.14% with each abdominal CT scan ( Brenner and Hall 2007 ). The majority of patients with intra-abdominal injury intervention (IAI-I) misclassified as low risk had distracting injury or intoxication; consider a lower threshold to obtain CT in these cases if there is clinical suspicion despite being classified as low or very low risk for IAI-I.
More Information
Sensitivity 97.0% (95% CI 93.7–98.9%) Specificity 42.5% (95% CI 41.6–43.4%) Negative predictive value 99.9% (95% CI 99.7–100%) Positive predictive value 2.8% (95% CI 2.4–3.2%) Negative likelihood ratio 0.07 (95% CI 0.03–0.15)