Prehospital Validation of the Assessment of Blood Consumption (ABC) Score.

INTRODUCTION: The Assessment of Blood Consumption (ABC) score is a previously validated scoring system designed to predict which severely injured trauma patients will require massive transfusion. When the ABC score is used in the prehospital setting to activate massive transfusion at the receiving hospital, a 23% decrease in mortality has been demonstrated. However, the ABC score was developed and validated using hospital data from the emergency department (ED). The sensitivity and specificity of the ABC score when calculated using data from the prehospital setting are unknown. We hypothesized that the sensitivity and specificity of the prehospital ABC score will be similar to the sensitivity and specificity of the ED ABC score. METHODS: A 5-year retrospective analysis (2015-2019) of highest-activation adult trauma patients arriving to a quaternary Level I trauma center by hospital-based helicopter air medical service (HEMS) was performed. Demographic, prehospital, ED triage, and blood product utilization data were collected. Prehospital ABC score was calculated using the highest heart rate, lowest systolic blood pressure, and focused assessment with sonography for trauma (FAST) exam results obtained prior to arrival at the trauma center. ED ABC score was calculated using ED triage vital signs and ED FAST results. Sensitivity, specificity, positive predictive value, negative predictive value, and the area under the receiver operating characteristics (AUROC) curve were calculated for each ABC score. RESULTS: 2,067 patients met inclusion criteria. Mean age 39 (±17) years, 76% male, 22% penetrating mechanism. Of these, 128 patients (6%) received massive transfusion using the definition from the original study. Prehospital ABC score at a cutoff of 2 was 51% sensitive and 85% specific for predicting massive transfusion, with 83% correctly classified and an AUROC = 0.73. ED ABC score at the same cutoff was 60% sensitive and 84% specific, with 83% correctly classified and an AUROC = 0.81. By logistic regression, the odds of massive transfusion increased by 2.76 for every 1-point increase in prehospital ABC score (95%CI 2.25-3.37, p < 0.001). CONCLUSIONS: The ABC score is a useful prehospital tool for identifying who will require massive transfusion. Future studies to evaluate the effect of the prehospital ABC score on clinical care and mortality are necessary.

Continuum of Care: A Multiagency Approach to Seamless Warmed Prehospital Whole Blood Resuscitation of a Patient with Noncompressible Truncal Hemorrhage.

BACKGROUND: Prehospital transfusion capabilities vary widely in the United States. Here we describe a case of prehospital resuscitation using warmed, whole blood in a patient with penetrating torso trauma and associated hemorrhagic shock. CASE REPORT: A 68-year-old man sustained a single gunshot wound to the left chest and was found to have a shock index of 1.5 at the time of emergency medical services (EMS) arrival. Rapid peripheral intravenous and central venous access enabled the infusion of warmed low-titer O-positive whole blood. The EMS crew intentionally resuscitated the patient before managing the airway by means of rapid sequence intubation. An air medical services helicopter crew assumed patient care from the ground EMS crew and continued the warmed, whole blood transfusion during the flight to a regional Level I trauma center. The patient went directly to the operating room from the helipad, underwent definitive operative management, and was ultimately discharged home on hospital day nine. CONCLUSION: Early recognition of hemorrhagic shock, implementation of prehospital transfusion protocols that emphasize transfusion of warmed blood without interruption, and an organized, regional approach to trauma care are critical for improving patient survival.