Validation of shock index pediatric-adjusted for children injured in warzones

BACKGROUND Shock Index Pediatric-Adjusted (SIPA) has been used to predict injury severity and outcomes after civilian pediatric trauma. We hypothesize that SIPA can predict the need for blood transfusion and emergent surgery among pediatric patients injured in warzones, where resources are limited and accurate triage is essential. METHODS Retrospective review of the DoD Trauma Registry for all patients 17 years or younger, from 2008 to 2015. Shock Index Pediatric-Adjusted was determined using vital signs recorded upon arrival to the initial level of care. Patients were classified into two groups (normal vs. elevated SIPA) using age-specific threshold values. The need for blood product transfusion (BPT) within 24 hours and emergent surgical procedures (ESP) was compared between groups. Intensive care unit admission, injury severity, and mortality were also compared. Regression analysis was performed to evaluate the relationship between SIPA and primary outcomes. RESULTS There were 2,121 patients included with a mean Injury Severity Score of 12 ± 10. The mechanism of injury was penetrating (63%), blunt (25%), and burns (12%). Patients with an elevated SIPA (43%) had a significantly greater need for BPT (49.2% vs. 25.0%) and ESP (22.9% vs. 16.0%), as well as mortality (10.3% vs. 4.8%) and intensive care unit admission (49.9% vs. 36.1%), all p less than 0.001. Regression analysis confirmed an elevated SIPA as independently associated with both BPT (odds ratio, 2.36; 95% confidence interval, 1.19-2.94; p < 0.001) and ESP (odds ratio, 1.29; 95% confidence interval, 1.01-1.64; p = 0.044). CONCLUSION This is the first study of SIPA in pediatric warzone trauma. Elevated SIPA is associated with significantly increased need for BPT and emergent surgery and may therefore serve as a valuable tool for planning and triage in austere settings. LEVEL OF EVIDENCE Prognostic/epidemiological, Level III.