Factors Identified That Reduce Radiation Exposure in Children with Traumatic Injuries

Because CT scans pose radiation hazards for children, the findings may enable doctors to determine which children do not need to be exposed to such imaging technology after a traumatic injury.

The study was published online in January 2012 first, in advance of an upcoming issue of the journal the Annals of Emergency Medicine. “CT scans involve significant radiation risk, especially for children, who are more vulnerable than adults to radiation’s effects,” said principal investigator and lead author of the study James Holmes, a professor of emergency medicine at the University of California (UC) Davis School of Medicine (Sacramento, USA). “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.”

The prospective study involved children who arrived at emergency departments in the PECARN network after blunt trauma to their torsos, such as sustained from 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), neurologic changes, abdominal pain, or tenderness, vomiting and abnormal breath sounds.

Children who had none of the factors when evaluated in the ED had only a 0.1% chance of having an abdominal injury that required acute intervention. For most of these cases, therefore, a CT scan, in all probability, would not provide additional useful information. According to the authors, the risk of developing a future cancer from radiation exposure from a CT scan in this setting (i.e., when lacking all seven factors) outweighs the risk of having a significant medical problem from the abdominal injury.

The investigators stated that 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 authorize a CT only 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. The authors stressed that clinical judgment must play an important role in determining whether a CT is required in each instance. Lengthening the time period of observation in the ED, and using findings from laboratory tests and ultrasonography, can also add to decision-making in cases of abdominal trauma.

According to Dr. Holmes, the prediction rule must be evaluated in another clinical trial designed specifically to assess 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 examining the role of ultrasonography in the assessment of abdominal trauma in children, and whether increasing its usage can lead to additional decrease of the need for CT scanning.

This study also was conducted through PECARN, a network of pediatric emergency departments throughout the United States that enables researchers to collect sufficient data to perform key studies on vital issues in pediatric emergency medicine. PECARN studies have earlier led to new standards of care for infants or children presenting with diabetic crisis, head trauma, and infections.

“Because of PECARN, we are uniquely positioned to perform large studies that can provide important information,” said Dr. Nathan Kuppermann, senior investigator of the study, who is professor of pediatrics and emergency medicine and chair of the department of emergency medicine at the UC Davis School of Medicine. “The results of such studies are making emergency medicine decision-making more of a science and leading to better and safer outcomes for children.”

Related Links:
University of California Davis School of Medicine
Pediatric Emergency Care Applied Research Network