Beware the Hematoma in Pediatric Minor Head Trauma
Burns E.C.M. et al. “Scalp Hematoma Characteristics Associated With Intracranial Injury in Pediatric Minor Head Injury.” Academic Emergency Medicine 2016;23:576–583.
Knowing a little bit more detail about the relationship between scalp hematoma and intracranial injuries is useful in the evaluation of pediatric patients of all ages with minor head trauma.
What scalp hematoma characteristics are associated with intracranial injury (ICI) in kids under 17 years of age with minor head trauma?
The study included 3,866 children 0-16 years of age presenting to the emergency room at 10 pediatric teaching hospitals in Canada. This was a secondary analysis of a prospective, multicenter observational study with consecutive enrollment of children with minor head injury. Children were included if they experienced blunt head trauma with loss of consciousness, amnesia, disorientation, two or more episodes of vomiting, or irritability. They were required to have a GCS of 13 or greater, and the injury must have occurred within the past 24 hours. No children with penetrating injuries, obvious depressed skull fractures, a focal neurologic exam, developmental delay, or suspicion of abuse were included. The primary outcome measure was any intracranial injury. Note that this is not a patient-centered outcome as the study does not elaborate on whether these were clinically relevant injuries.
The study group had a 9.3% overall frequency of ICI with presence of hematoma. In all age groups, hematoma increased the odds of ICI, although this relationship was greatest in the 0-<6mo range (LR = 13.5). Hematomas characterized as large (>3cm) and boggy carried an increased likelihood ratio of 9.9 when compared to those characterized as small (1-3cm) and localized, with a likelihood ratio of 3. Temporal or parietal location carried the greatest LR of ICI (6), followed by occipital (5.6) and frontal (2.1).
The takeaway: Hematomas anywhere, especially large, boggy, or non-frontal ones, have strong likelihood ratios for intracerebral injury. However, from these data, it is not clear what other symptoms the patients had, and the significance of an isolated hematoma. Absence of hematoma is reassuring, and these data as a whole can help guide the practitioner in equivocal cases.