ORLANDO (FRONTLINE MEDICAL NEWS) – A new predictive method could limit unnecessary computed tomography scans on pediatric, blunt force trauma patients at low risk for intra-abdominal injury, according to a study presented at the annual scientific assembly of the Eastern Association for the Surgery of Trauma.

With values for five clinical variables, the prediction rule would eliminate the need to subject some patients to unwarranted radiation exposure, which has become a growing health and financial concern for medical institutions.

“CT utilization rates in pediatric blunt trauma are very high, at a rate of 40%-60%, despite a relatively low incidence of intra-abdominal injury after abdominal trauma,” according to presenter Chase A. Arbra, MD, of the department of surgery at the Medical University of South Carolina, Charleston. “With increasing concerns regarding the cost and radiation exposure in children, our group is focusing on research to safely avoid these unnecessary scans.”

The rule, developed by the Pediatric Surgery Research Collaborative ( PedSRC ), evaluates abdominal wall trauma and tenderness, complaint of abdominal pain, aspartate aminotransferase level greater than 200 U/L, abnormal pancreatic enzymes, and abnormal chest x-rays to determine a patient’s risk of having an intra-abdominal injury (IAI). If none of the five variables in a patient is abnormal, the finding is considered negative and the patient is considered to be at very low risk for having an IAI or an IAI requiring acute intervention (IAI-I).

Investigators studied 2,435 pediatric blunt trauma patients with all five clinical variables documented within 6 hours of arrival, using data gathered from the Pediatric Emergency Care Applied Research Network .

Patients were an average of 9.4 years old, with an IAI rate of 9.7% (n = 235) and an IAI-I rate of 2.5% (n = 60); 61.1% of the patients had a CT scan.

Prediction sensitivity of the method was 97.5% for IAI and 100% for IAI-I, said Dr. Arbra. Negative predictive value for the model was 99.3% for IAI and 100% for IAI-I.

Patients who were found to have aspartate aminotransferase level greater than 200 U/L were at the highest risk of IAI (52.6%) and IAI-I (11.9%), according to investigators. One-third of the test population was found to be at very low risk after using the prediction model, according to Dr. Arbra, with 46.8% of them still undergoing a CT scan. Of those tested, six patients had IAI that was not predicted by the model, three of whom were intubated. Because CT scans were not required and there was no follow-up after discharge, investigators are not able to determine if any minor IAI was missed.

Despite these limitations, the highly sensitive rule shows great promise, according to Dr. Arbra.

“Patients with 0-5 variables, even patients who were involved in a high impact mechanism, could potentially forgo CT scans safely.”

A closer look at the 26 patients who only had abdominal pain showed that only 1 had IAI, suggesting that patients with only abdominal pain could be safely observed with only serial exams, according to Dr. Arbra.

Investigators plan to conduct a prospective study that will include older patients.

Dr. Arbra concluded, “The rule could potentially help centers to determine who could avoid imaging prior to transfer and potentially could one day be used to see who could be discharged.”

Dr. Arbra reported no relevant financial disclosures.

SOURCE: Arbra CA. EAST Scientific Assembly 2018, paper #7.