Comparisons of Trauma Outcomes and Injury Severity Score

Abstract

Trauma is a global health problem and a leading cause of mortality. One of the major predictors of trauma mortality is the Injury Severity Score (ISS). Theoretically, as the ISS increases, the probability of survival decreases; ISS = 75 is considered to be not survivable. Studies have shown that some deaths are preventable and some potentially preventable. Hemorrhagic shock is a potentially preventable cause of trauma mortality. A retrospective database review was conducted of the Mississippi Trauma Registry and point-by-serial correlational analyses were conducted to determine the direction of any significant relations between blood product usage, traditional vital signs, and shock index. Pearson correlation, logistic regressions, and odds ratio calculation results revealed that shock index can signal impending hemorrhagic compromise better than traditional vital signs; thus, facilitating early intervention, specifically, as heart rate and shock index increase, the use of blood products increases, and as blood pressure increases, the use of blood products decreases. Independent t tests for shock index and ISS revealed significant differences in the means with relationship to the subgroups "Dead" and "Alive." Higher ISS were found to correlate with higher shock indices. Evaluation of ISS and survivability demonstrates that ISS = 75 is survivable and should not lead one to reflexively assume otherwise. A total mortality finding of only 1.58% (n = 2,010) was unexpected but very encouraging.