Based on their clinical assessment, emergency physicians obtained CT scans for a total of 14,969 children and found ciTBIs in 376—35% and 0.9% of the 42,412 study participants, respectively. Sixty patients required neurosurgery. Investigators ascertained outcomes for the 65% of participants who did not undergo CT imaging via telephone, medical record, and morgue record follow-up; 96 patients returned to a participating health care facility for subsequent care and CT scanning as a result. Of those 96, 5 patients were found to have a TBI. One child had a ciTBI and was hospitalized for 2 nights for a cerebral contusion.
The investigators used established prediction rule methods and Standards for the Reporting of Diagnostic Accuracy Studies (STARD) guidelines to derive the rules. They assigned a relative cost of 500 to 1 for failure to identify a patient with ciTBI vs incorrect classification of a patient who did not have a ciTBI.
Negative finding=0 of 6 predictors
The rules that were derived and validated on the basis of this study are more detailed than previous pediatric prediction rules. For children <2 years, the new standard features 6 factors: altered mental status, palpable skull fracture, loss of consciousness (LOC) for ≥5 seconds, nonfrontal scalp hematoma, severe injury mechanism, and acting abnormally (according to the parents).
The prediction rule for children ≥2 years has 6 criteria, as well, with some key differences. While it, too, includes altered mental status and severe injury mechanism, it also includes clinical signs of basilar skull fracture, any LOC, a history of vomiting, and severe headache. The criteria are further defined, as follows:
Altered mental status: GCS <15, agitation, somnolence, repetitive questions, or slow response to verbal communication.
Severe injury mechanism: Motor vehicle crash with patient ejection, death of another passenger, or vehicle rollover; pedestrian or bicyclist without a helmet struck by a motor vehicle; falls of >3 feet for children <2 years and >5 feet for children ≥2; or head struck by a high-impact object.
Clinical signs of basilar skull fracture: Retroauricular bruising—Battle’s sign (peri-orbital bruising)—raccoon eyes, hemotympanum, or cerebrospinal fluid otorrhea or rhinorrhea.
In both prediction rules, a child is considered negative and, therefore, not in need of a CT scan, only if he or she has none of the 6 clinical predictors of ciTBI.
New rules are highly predictive
In the validation cohorts, the rule for children <2 years had a 100% negative predictive value for ciTBI (95% confidence interval [CI], 99.7-100) and a sensitivity of 100% (95% CI, 86.3-100). The rule for the older children had a negative predictive value of 99.95% (95% CI, 99.81-99.99) and a sensitivity of 96.8% (95% CI, 89-99.6).
In a child who has no clinical predictors, the risk of ciTBI is negligible—and, considering the risk of malignancy from CT scanning, imaging is not recommended. Recommendations for how to proceed if a child has any predictive factors depend on the clinical scenario and age of the patient. In children with a GCS score of 14 or with other signs of altered mental status or palpable skull fracture in those <2 years, or signs of basilar skull fracture in kids ≥2, the risk of ciTBI is slightly greater than 4%. CT is definitely recommended.
In children with a GCS score of 15 and a severe mechanism of injury or any other isolated prediction factor (LOC >5 seconds, non-frontal hematoma, or not acting normally according to a parent in kids <2; any history of LOC, severe headache, or history of vomiting in patients ≥2), the risk of ciTBI is less than 1%. For these children, either CT or observation may be appropriate, as determined by other factors, including clinician experience and patient/parent preference. CT scanning should be given greater consideration in patients who have multiple findings, worsening symptoms, or are <3 months old.
WHAT’S NEW: Rules shed light on hazy areas
These new PECARN rules perform much better than previous pediatric clinical predictors and differ in several ways from the 8 older pediatric head CT imaging rules. The key provisions are the same—if a child has a change in mental status with palpable or visible signs of skull fracture, proceed to imaging. However, this study clarifies which of the other predictors are most important. A severe mechanism of injury is important for all ages. For younger, preverbal children, a nonfrontal hematoma and a parental report of abnormal behavior are important predictors; vomiting or a LOC for <5 seconds is not. For children ≥2 years, vomiting, headache, and any LOC are important; a hematoma is not.