Shock Index versus ABC Score to Predict Need for Massive Transfusion in Trauma Patients

Abstract

           Management of Massive hemorrhage in trauma patients remains an integral factor in their treatments due to its relation with the patient outcome in terms of disability and mortality. This retrospective cohort study aimed to compare the precision of shock index (SI) and assessment of blood consumption (ABC) score as tools to predict the need for a massive transfusion (MT) in trauma patients. The medical records of patients visited the emergency room, Sakon Nakhon hospital, from January 1^st, 2015 to August 31^st, 2019 were reviewed through the hospital computer database. One hundred and eighteen samples were enrolled. Data were calculated for SI and ABC scores and analyzed by the Chi–square test, 95% confident interval (95% CI), sensitivity, specificity, area under the curve of the receiver operating characteristic (AUROC), positive predictive value (PPV), negative predictive value (NPV) and Likelihood ratio (LR).

          The study revealed that MT was utilized in 62.50% of patients with SI ≥ 1 but only in 24.3% of patients with SI < 1. This was statistically significant difference (p < 0.001). Similarly, MT was utilized in 82.40% of patients with ABC score ≥ 2 but only in 22.60% of patients with ABC score < 2. This was statistically significant difference (p < 0.001). The SI ≥ 1 had the sensitivity 63.83% (95% CI = 50.09–77.57), specificity 74.65% (95% CI = 64.53–84.77), PPV 62.50% and positive LR 0.48. Meanwhile, the ABC score ≥ 2 had the sensitivity 59.57% (95% CI = 45.54–73.61), specificity 91.55% (95% CI = 85.08– 98.02), PPV 82.35% and positive LR 0.44. When compared the AUROC of ABC score (AUC = 0.833, 95% CI = 0.756–0.910) and SI (AUC = 0.788, 95% CI = 0.707–0.807), the ABC score system had more accurate prediction for massive transfusions than that of SI. Therefore, the ABC score ≥ 2 could be used as a tool for predicting the need for massive transfusions in trauma patients.

          Keywords: Massive transfusion, Massive hemorrhage, Shock Index, ABC score