Novel Trauma Composite Score Is A More Reliable Predictor Of Mortality Than Injury Severity Score In Pediatric Trauma.

BACKGROUND The equivalent injury severity score (ISS) cutoffs for severe trauma vary between adult (ISS>16) and pediatric (ISS>25) trauma patients. We hypothesized that a novel injury severity prediction model, which incorporates age and mechanism of injury, would outperform standard ISS cutoffs. METHODS The 2010-2016 NTDB was queried for pediatric trauma patients. Cut point analysis was used to determine the optimal ISS for predicting mortality for age and mechanism of injury. Linear discriminant analysis (LDA) was implemented to determine prediction accuracy, based on AUC, of: ISS cutoff of 25 (ISS25), shock index pediatric adjusted (SIPA), an age-adjusted ISS/abbreviated Trauma Composite Score (aTCS), and our novel Trauma Composite Score (TCS) in blunt trauma. The TCS consisted of significant variables (AIS, GCS, Gender, and SIPA) selected a priori for each age. RESULTS There were 109,459 blunt (BT) and 9,292 penetrating trauma (PT) patients studied. There was a significant difference in ISS (BT:9.3 ± 8.0 vs. PT:8.0 ± 8.6, p<0.01) and mortality (BT:0.7% vs. PT:2.7%, p<0.01). Analysis of the entire cohort revealed an optimal ISS cut point of 25 (AUC 0.95, sensitivity 0.86, specificity 0.95); however, the optimal ISS ranged from 18-25 when evaluated by age and mechanism. LDA model AUCs varied significantly for each injury metric when assessed for BT and PT (PT- adjusted ISS: 0.94 ± 0.02 vs ISS 25: 0.88 ± 0.02 vs SIPA: 0.62 ± 0.03; p < 0.001; BT -adjusted ISS: 0.96 ± 0.01 vs. ISS 25: 0.89± 0.02 vs. SIPA: 0.70 ± 0.02; p < 0.001). When injury metrics were assessed across age groups in BT, TCS and aTCS outperformed all models across all ages. CONCLUSIONS Current use of ISS in pediatric trauma may not accurately reflect severity of injury. The TCS and aTCS which incorporate both age and mechanism outperform standard injury metrics in mortality prediction in blunt trauma. STUDY TYPE Retrospective Review. LEVEL OF EVIDENCE IV.