Clinical factors can identify children at low risk of traumatic brain injury

Clinical question Can clinical factors identify children with head injury who are at low risk for clinically important traumatic brain injury?

Bottom line In this large study, clinical factors identified which children with head injuries were unlikely to have a serious brain injury. Because CT uses enormous amounts of radiation and children are especially vulnerable to potential adverse effects of radiation exposure, these factors can help reduce the use of CTs. (Level of evidence = 1b–)

Synopsis This team of researchers systematically evaluated more than 42,000 children presenting to emergency departments (EDs) within 24 hours of sustaining head trauma. The researchers excluded children with trivial injuries (eg, trip and fall, walking into stationary objects) and children with penetrating injuries or pre-existing neurologic disorders. Each child underwent a standardized clinical assessment. The researchers defined clinically important brain injuries as those that resulted in death, neurosurgical intervention, intubation, or more than 2 days in the hospital. A pediatric radiologist unaware of the child's clinical characteristics interpreted radiographs whenever CT was performed. The decision to perform CT was left to the discretion of the ED physician. To identify children with clinically important brain injuries missed during the initial assessment, a researcher contacted the children's parents 7 to 90 days after discharge from the ED. The researchers also split children into two age groups: younger than 2 years and 2 years and older. The researchers used data from the first 2 years of the study to derive clinical prediction rules. These were subsequently validated on children during the last 6 months of the study. Approximately one third of the children had CT, of whom 5% had radiographic signs of traumatic brain injury and 1% had clinically important brain injuries. For children younger than 2 years, the presence of any of the following clinical factors were useful in identifying children with clinically important brain injuries: altered mental status, occipital/parietal/temporal scalp hematoma, loss of consciousness for longer than 5 seconds, severe mechanism of injury, palpable skull fracture, or parent report of not acting normally. The researchers defined severe mechanism of injury as: motor vehicle crash with ejection of the child, death of another passenger, or rollover; pedestrian or bicyclist without helmet struck by a motorized vehicle; falls of more than 1.5 meters (5 feet) for children 2 years and older and more than 0.9 meter (3 feet) for those younger than 2 years; or head struck by a high-impact object. In the validation set, the presence of any of these factors was 100% sensitive (95% CI, 86.3%-100%), but only 54% specific (51.6%-55.8%). In other words, a child having none of these factors is very unlikely to have a serious injury and does not need CT. For children 2 years and older, the presence of any of the following clinical factors helps identify children with clinically important brain injuries: altered mental status, loss of consciousness, vomiting, severe mechanism of injury, clinical signs of basilar skull fracture, or severe headache. In the validation set, the presence of any of these factors was 97% sensitive (89%-99.6%), but only 60% specific (58.6%-61%). A child having none of these factors is very unlikely to have a serious injury and does not need CT.

Kuppermann N, Holmes JF, Dayan PS, et al; Pediatric Emergency Care Applied Research Network (PECARN). Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet. 2009;374(9696):1160-1170.