Pre-hospital assessment of trauma associated severe hemorrhage (phTASH) - analysis of TraumaRegister DGU data from 2015-2021.

BACKGROUND

Prehospital transfusions are becoming increasingly popular in Europe. Blood products play an important role in the treatment of massive hemorrhage but may pose a potential risk to the patient when the indication is inconclusive such as in a prehospital setting. Simple scores are required in order to initiate targeted therapy and to use the valuable resource of blood comprehensibly in the prehospital setting. With the Assessment of Blood Consumption (ABC)-score and the reversed Shock Index GCS (rSIG)-score, two scores with a good predictive quality for the occurrence of massive transfusion have already been described. However, both scores were validated with in-hospital data that do not correspond to the characteristics of the European trauma population. Aim of this study is to validate both scores with data that represent the European trauma population and to discuss the usability to justify prehospital blood transfusion.

METHODS

Using data from the TraumaRegister DGU from the years 2015-2021, this study examines the proportion of patients who required a transfusion or massive transfusion after hospital admission. The results are used to calculate the area under the receiver operating characteristics curve (AUROC) to assess the predictive quality of the ABC score and the rSIG score for an European trauma population. A logistic regression analysis is used to identify the items of both scores with the highest impact on the predictive quality of each score. The items with the most influence were then combined to form the new prehospital Trauma Associated Severe Hemorrhage (phTASH) score.

RESULTS

We included 63,946 datasets. 8.5% of all patients received a transfusion and 1% a mass transfusion after hospital admission. The mean Injury Severity Score (ISS) for patients with massive transfusion was 39.9 vs. 16.8 without massive transfusion. The ABC score has an AUROC of 0.711 (0.702-0.719) for any transfusion (≥ 1 packed Red Blood Cells; pRBC) and of 0.806 (0.786-0.826) for massive transfusion (≥ 10 pRBC). The rSIG score has an AUROC of 0.737 (0.730-0.744) vs. 0.807 (0.790-0.824) respectively. The phTASH score is calculated with an AUROC of 0.747 (0.737-07.53) for the prediction of any transfusion and an AUROC of 0.834 (0.816-0.952) for the prediction of massive transfusion after severe trauma. The three items with the greatest influence on the score results are the positive Focused Assessment with Sonography in Trauma (FAST) examination (OR 5.28), systolic blood pressure < 90mmHg (OR 2.94) and a shock index > 1 (OR 2.49).

CONCLUSIONS

The need for transfusion can easily be assessed even in the prehospital setting. The new developed phTASH score has a high predictive accuracy for transfusions after trauma. The identification of a positive FAST examination as the element with the greatest impact on predicting a patient's need for transfusion emphasizes the importance of prehospital ultrasound.