Combined Qualitative Assessment of Admission Shock Index, Base Deficit, and Lactate to Enhance Mortality Predication After Blunt Trauma.

Abstract

IntroductionThe role of elevated shock index is increasingly recognized as a vital indicator in the assessment of mortality rates in trauma patients. Its role in combination with other parameters is crucial yet underexplored in predicting outcomes. We hypothesized that qualitative assessment of elevated admission shock index, elevated base deficit/excess, and elevated lactate in combination would best predict mortality after blunt trauma.MethodsThis study was a retrospective review of trauma registry data on blunt trauma patients from 2012 to 2021 at a level 1 trauma center to evaluate the impact of elevated SI (>0.7), elevated lactate 2 mmol/L to 5 mmol/L, and elevated base deficit ≤-2 mmol/L at admission on predicting mortality. We used these parameters as qualitative and categorical predictors rather than continuous measures. A multivariate logistic regression model was developed, with shock index severity stratification and mortality as primary outcomes.ResultsA total of 4794 patients (151 non-survivors) were included in the analysis. Non-survivors had higher rates of elevated SI + elevated lactate + elevated BD (13.9% vs 5.8%, P < 0.001) with highest overall OR (11.7, P < 0.001) compared to other parameters (age 5.5, severe ISS 9.5, and GCS <8 10.3). When stratified by severity, patients with moderate SI (1.0 < SI <1.4) had a significantly increased risk of mortality in combination with elevated lactate and elevated base deficit (OR 21.1, P < 0.001).ConclusionWe previously reported a qualitative model predicting blunt trauma mortality rates using elevated lactate and elevated base deficit. Combining admission SI, whether mild and moderate, with elevated lactate and elevated base deficit as qualitative "elevated" biomarkers yielded a more robust predictive model and highest OR for predicting mortality in blunt trauma non-survivors, with an 11.7-fold increase compared to survivors. This was higher than the individual parameters or other combinations.