Compared with unadjusted shock index (SI) (heart rate/systolic blood pressure), age-adjusted SI improves identification of negative outcomes after injury in pediatric patients. We aimed to further evaluate the utility of age-adjusted SI to predict negative outcomes in pediatric trauma.
We performed an analysis of patients younger than 15 years using the National Trauma Data Bank. Elevated SI was defined as high normal heart rate divided by low-normal blood pressure for age. Our primary outcome measure was mortality. Secondary outcomes included need for a blood transfusion, ventilation, any operating room/interventional radiology procedures, and intensive care unit stay. Multiple logistic regressions were performed.
Twenty-eight thousand seven hundred forty-one cases met the study criteria. The overall mortality rate was 0.7%, and 1.7% had an elevated SI. Patients with an elevated SI were more likely (P < 0.001) to require blood transfusion, ventilation, an operating room/interventional radiology procedure, or an intensive care unit stay. An elevated SI was the strongest predictor for mortality (odds ratio [OR] 22.0) in pediatric trauma patients compared with hypotension (OR, 12.6) and tachycardia (OR, 2.6).
Elevated SI is an accurate and specific predictor of morbidity and mortality in pediatric trauma patients and is superior to tachycardia or hypotension alone for predicting mortality.