Increased use of computed tomography (CT) in children is concerning owing to the cancer risk from ionizing radiation, particularly in children younger than 2 years. A guardian report that a child is acting abnormally is a risk factor for clinically important traumatic brain injury (ciTBI) and may be a driving factor for CT use in the emergency department.Objective
To determine the prevalence of ciTBIs and TBIs in children younger than 2 years with minor blunt head trauma and a guardian report of acting abnormally with (1) no other findings or (2) other concerning findings for TBI.Design, Setting, and Participants
Secondary analysis of a large, prospective, multicenter cohort study that included 43 399 children younger than 18 years with minor blunt head trauma evaluated in 25 emergency departments. The study was conducted on data obtained between June 2004 and September 2006. Data analysis was performed between August 21, 2014, and March 9, 2015.Exposures
A guardian report that the child was acting abnormally after minor blunt head trauma.Main Outcomes and Measures
The prevalence of ciTBI (defined as death, neurosurgery, intubation for >24 hours, or hospitalization for ≥2 nights in association with TBI on CT imaging) and TBI on CT imaging in children with a guardian report of acting abnormally with (1) no other findings and (2) other concerning findings for TBI.Results
Of 43 399 children in the cohort study, a total of 1297 children had reports of acting abnormally, of whom 411 (31.7%) had this report as their only finding. Reported as percentage (95% CI), 1 of 411 (0.2% [0-1.3%]) had a ciTBI, and 4 TBIs were noted on the CT scans in 185 children who underwent imaging (2.2% [0.6%-5.4%]). In children with reports of acting abnormally and other concerning findings for TBI, 29 of 886 (3.3% [2.2%-4.7%]) had ciTBIs and 66 of 674 (9.8% [7.7%-12.3%]) had TBIs on CT.Conclusions and Relevance
Clinically important TBIs are very uncommon, and TBIs noted on CT are uncommon in children younger than 2 years with minor blunt head trauma and guardian reports of the child acting abnormally with no other clinical findings suspicious for TBI. Computed tomographic scans are generally not indicated in these children although observation in the emergency department may be warranted.