7 factors rule out need for CT scans in kids

UC DAVIS (US) — A new study identifies seven factors that can help emergency room doctors decide if a child needs a computed tomography (CT) scan following blunt trauma to the abdomen.

Because CT scans pose radiation hazards for youngsters, the findings may protect children who don’t need to be exposed to such tests after a traumatic injury.

“CT scans involve significant radiation risk, especially for children, who are more vulnerable than adults to radiation’s effects,” says principal investigator James Holmes, professor of emergency medicine at the University of California, Davis School of Medicine. “We have now identified a population of pediatric patients that does not typically benefit from a CT scan, which is an important step in reducing radiation exposure.”


Published online in the journal Annals of Emergency Medicine, the prospective study involved 12,000 children who arrived at US emergency departments in the Pediatric Emergency Care Applied Research Network (PECARN) after blunt trauma to their torsos, such as those sustained in a car or bicycle crash, a fall, or an assault.

A variety of factors related to the children’s histories and clinical presentations were evaluated. Among these, seven were identified by statistical analysis to correlate with risk for involving a clinically important injury. The factors included evidence of trauma on the abdomen or chest (such as seat-belt marks), neurological changes, abdominal pain or tenderness, abnormal breath sounds, and vomiting.

Children who had none of the factors when evaluated in the emergency department had only a 0.1 percent chance of having an abdominal injury that required acute intervention. For the great majority of these cases, therefore, a CT scan would not likely provide additional useful information.

The risk of developing a future cancer from radiation exposure from a CT scan in this situation (when lacking all seven factors) outweighs the risk of having a significant medical problem from the abdominal injury, researchers say.

The prediction rule is intended only to help rule out the need for CT for children when none of the seven factors is present. However, the rule does not mandate a CT solely based on any one of the factors being present. If the prediction rule were used in that way, CT usage would actually increase over current levels.

Clinical judgment must play an important role in determining whether a CT is needed in each case, the researchers say. Extending the period of observation in the emergency department, and using findings from laboratory tests and ultrasonography, can also contribute to decision-making in cases of abdominal trauma.

According to Holmes, the prediction rule must be tested in another clinical trial designed specifically to evaluate its validity before being generally adopted. He expects that this will be carried out in the near future.

Another related ongoing study at UC Davis Medical Center is investigating the role of ultrasonography in the evaluation of abdominal trauma in children, and whether increasing its usage can lead to further reduction of the need for CT scans. This study also was conducted through PECARN.

Researchers from  emergency departments in Maryland, Massachusetts, Michigan, Missouri, New York, Ohio, Utah, Wisconsin and Washington, D.C. contributed to the study.

Source: UC Davis