1. Copyright restrictions may apply JAMA Pediatrics Journal Club Slides: Isolated Loss of Consciousness in Head Trauma Lee LK, Monroe D, Bachman MC, et al; Traumatic Brain Injury (TBI) Working Group of the Pediatric Emergency Care Applied Research Network (PECARN). Isolated loss of consciousness in children with minor blunt head trauma. JAMA Pediatr. Published online July 7, 2014. doi:10.1001/jamapediatrics.2014.361.

2. Copyright restrictions may apply Background –Overall risk of clinically important traumatic brain injury (ciTBI) in children with minor blunt head trauma is low. –Loss of consciousness (LOC) is frequently a driving factor for computed tomographic (CT) evaluation after blunt head trauma in children, even when there are no other signs or symptoms of head trauma (isolated LOC). –LOC was identified as one of 6 factors in the PECARN prediction rules for ciTBI: Prediction rule for children aged 5 seconds. Prediction rule for children aged ≥2 years: any LOC. –CT carries nonnegligible risk of radiation-induced malignancy. Study Objective –To determine the risk for ciTBIs in children with isolated LOC. Introduction

3. Copyright restrictions may apply Study Design –Planned secondary analysis. –Large prospective multicenter cohort study. Setting –25 Emergency departments in PECARN. Patients –Aged 0-18 years. –Blunt head trauma within 24 hours of emergency department presentation. –Glasgow Coma Scale scores of 14-15. –Exclusions: Trivial injury mechanism. Significant comorbidities. Neuroimaging obtained at a transferring hospital. Methods

4. Copyright restrictions may apply Methods Outcomes –ciTBI: TBI associated with the following: Death from intracranial injury. Any neurosurgical intervention. Intubation >24 hours for head injury. Hospitalization ≥2 nights owing to head injury in association with TBI on CT. Limitations –Not all children had CT evaluation. –Some missing data, so unable to determine isolated LOC status in all enrolled children. –Possibility of varying interpretations of history of LOC recorded on data collection forms by different clinicians. –Relatively small sample size of children aged <2 years with isolated LOC.

5. Copyright restrictions may apply Results Any LOC occurred in 15.4% (6286 of 42 412 enrolled in parent study). Prevalence of ciTBI: –Any history of LOC: 2.5%. –No history of LOC: 0.5%. –Rate difference, 2.0% (95% CI, 1.7-2.5). History of LOC recorded by 27.8% of treating clinicians as one of the most important indications influencing decision to obtain CT. Risk ratio for ciTBI in isolated LOC compared with LOC with other PECARN predictors: –Children aged <2 years: 0.13 (95% CI, 0.005-0.72). –Children aged ≥2 years: 0.10 (95% CI, 0.06-0.19).

6. Copyright restrictions may apply Results ciTBI with isolated LOC (no other PECARN clinical predictors): –Predictors for children aged 5 seconds, altered mental status, nonfrontal scalp hematoma, severe mechanism of injury, palpable skull fracture, acting abnormally per parent. –Predictors for children aged ≥2 years: any LOC, altered mental status, vomiting, signs of basilar skull fracture, severe mechanism of injury, severe headache. –13 of 2780 children (0.5%; 95% CI, 0.2-0.8). ciTBI with expanded definition of isolated LOC: –No other age-specific PECARN predictors. –No other clinical factors associated previously with TBI: seizures, amnesia, neurologic deficit, any scalp hematoma, any traumatic scalp finding. –1 of 576 children (0.2%; 95% CI, 0.0-1.0).

7. Copyright restrictions may apply Results Comparison of Children With PECARN-Isolated LOC vs Children With LOC and Other PECARN Predictors by Age Group OutcomeAge Group, yNo. No./No. (%) [95% CI] PECARN- Isolated LOC (n = 2780) Non-isolated LOC With Other PECARN Predictors (n = 3070) Relative Risk (95% CI) TBI on CT (246 of 4723 with CT scans) <2354 2/90 (2.2) [0.3-7.8] 24/264 (9.1) [5.9-13.2] 0.24 (0.02-0.87) ≥24369 36/1903 (1.9) [1.3-2.6] 184/2466 (7.5) [6.5-8.6] 0.25 (0.18-0.36) ciTBI (150 of 5850) <2504 1/157 (0.6) [0.0-3.5] 17/347 (4.9) [2.9-7.7] 0.13 (0.005-0.72) ≥25346 12/2623 (0.5) [0.2-0.8] 120/2723 (4.4) [3.7-5.2] 0.10 (0.06-0.19)

8. Copyright restrictions may apply Comment LOC is common in children after blunt head trauma. –It is an important factor influencing use of CT for evaluation. Overall risk for ciTBI for children with a history of LOC is higher than for children without LOC, but it includes other signs and symptoms of TBI. Children with isolated LOC had a very low rate of ciTBI (0.5%). The ciTBI rate was even lower in the group with the expanded definition of isolated LOC (0.2%). There was an incremental risk for ciTBI with addition of 1 PECARN predictor in conjunction with a history of LOC. Determining whether LOC occurred with or without other ciTBI risk factors is important in CT decision making.

9. Copyright restrictions may apply Comment Previous studies, including other derived clinical prediction rules for TBI, have not consistently included LOC as a risk factor. Literature has limited data on risk of ciTBI in the setting of isolated LOC. PECARN ciTBI age-specific prediction rules include LOC as a factor. –Presence of LOC alone does not place child at high risk. With isolated LOC, CT evaluation is unlikely to be beneficial. –Very low risk for ciTBI with normal physical examination findings and no other signs or symptoms of ciTBI. Observation before CT decision making can safely decrease CT use.

10. Copyright restrictions may apply If you have questions, please contact the corresponding author: –Lois K. Lee, MD, MPH, Division of Emergency Medicine, Boston Children’s Hospital, 300 Longwood Ave, Boston, MA 02115 (lois.lee@childrens.harvard.edu). Funding/Support This study was supported by grant R40MC02461 from the Health Resources and Services Administration/Maternal and Child Health Bureau (HRSA/MCHB) Division of Research, Education and Training (DRTE) and the Emergency Medical Services for Children (EMSC) Program. The PECARN is supported by the HRSA/MCHB/EMSC Program through the following cooperative agreements: U03MC00001, U03MC00003, U03MC00006, U03MC00007, U03MC00008, U03MC22684, and U03MC22685. The PECARN is supported by cooperative agreements U03MC00001, U03MC00003, U03MC00006, U03MC00007, U03MC00008, U03MC22684, and U03MC22685 from the EMSC program of the MCHB/HRSA. Conflict of Interest Disclosures None reported. Contact Information