CT Scans Frequently Unnecessary After Head Injuries in Children

New findings show that a period of observation in children with head injuries can avoid unnecessary exposure to radiation from computed tomography (CT) scanning.

In general, about half of US children taken to hospital emergency departments (EDs) for a head injury receive a head CT scan, often to ease worried parents' concerns. However, true traumatic brain injury is uncommon. A multicenter study of more than 40,000 children with minor blunt head trauma demonstrated that allowing a period of observation can reduce the use of head CT by as much as half without compromising care and without exposing children to ionizing radiation.

The study's findings were published in the June 2011 issue of the journal Pediatrics, published online May 9, 2011. "Only a small percentage of children with blunt head trauma really have something serious going on," said Lise Nigrovic, MD, MPH, of Children's Hospital Boston (MA, USA), who co-led the study with Nathan Kuppermann, MD, MPH, chair of the department of emergency medicine at the University of California, Davis (UC Davis; USA). "If you can be watched in the ED for a few hours, you may not need a CT."

This change in practice would not only be cost saving, but is better medical care, according to the researchers. Drs. Nigrovic, Kuppermann, and colleagues analyzed the outcomes of children presenting at 25 different emergency departments, as part of a large prospective study conducted by the Pediatric Emergency Care Applied Research Network (PECARN). Of 40,113 children whose records could be analyzed, 5,433 (14%) were observed before making a decision about CT use. Observation times varied, as did the severity of head trauma.

Overall, the children who were observed had a lower rate of CT than those not observed (31 vs. 35%). When the researchers correlated the observed and nonobserved groups for severity of head injury and the practice style of different hospitals, this difference was more pronounced: The probability of a CT scan in the observed group was about half that of similar nonobserved patients (odds ratio, 0.53). In particular, children whose symptoms improved during observation were less likely to eventually have a CT.

Allowing for an observation period did not compromise safety, the study found: Clinically important traumatic brain injury--resulting in death, neurosurgical intervention, intubation for more than 24 hours, or hospital admission for two nights or more--was equally uncommon in the observed and nonobserved groups (0.75 vs. 0.87%).

The investigators noted that cranial CT imaging itself presents additional risks for children. Children's growing brain tissue is more sensitive to ionizing radiation than adults are, and because of their longer life expectancy, their lifetime risk of developing a radiation-induced malignancy is greater.

The researchers were not able to determine the actual length of time the children were observed in the ED, a problem they would like to investigate in the future. Practice guidelines from the American Academy of Pediatrics (Elk Grove Village, IL, USA) recommend a child be carefully observed for four to six hours after injury.

"There is a clear need to develop appropriate and safe guidelines for decreasing the number of inappropriate head CT scans that we do on children," said Dr. Kuppermann. "The results of this analysis demonstrate that a period of observation before deciding to use head CT scans on many injured children can spare children from inappropriate radiation when it is not called for, while not increasing the risk of missing important brain injuries."

Dr. Nigrovic offered the following general guidelines for parents whose child has a head injury: (1) Check with the child's primary care clinician before taking the child to the ED. (2) If the child has headache, vomiting, and/or confusion, or symptoms that worsen over time, an ED visit is appropriate. (3) The ED clinician may reasonably choose to observe your child for several hours once you arrive before deciding about a head CT. (4) The change of symptoms over time is an important factor in deciding whether to obtain a cranial CT.

Related Links:
Children's Hospital Boston
University of California, Davis