The Extremity/Mechanism/Shock Index/GCS (EMS-G) score: A novel pre-hospital scoring system for early and appropriate MTP activation Alexandra Kovar a , Heather Carmichael a , Robert C. McIntyre Jr. a , Jacob Mago b , Alicia Heelan Gladden a , Erik D. Peltz a , Franklin L. Wright a, * a Division of GI, Trauma, and Endocrine Surgery, Department of Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, USA b University of Colorado School of Medicine, Aurora, CO, USA article info Article history: Received 14 March 2019 Received in revised form 1 July 2019 Accepted 16 August 2019 Keywords: Pre-hospital Massive transfusion Trauma abstract Background: Numerous in-hospital scoring systems to activate massive transfusion protocols (MTP) have been proposed; however, to date, pre-hospital scoring systems have not been robustly validated. Many trauma centers do not have blood or pre-thawed plasma available in the trauma bay, leading to delays in balanced transfusion. This study aims to assess pre-hospital injury and physiologic parameters to develop a pre-hospital scoring system predictive of need for massive transfusion (MT) prior to patient arrival. Methods: A retrospective review of all adult full and partial trauma team activations from July 2014eJuly 2018 from an urban level 2 trauma center was performed utilizing our trauma registry. Stepwise logistic regression analysis was performed to develop a new scoring system, with point totals assigned pro- portional to the odds ratios of requiring MT for each variable. Internal validation of the EMS-G score was performed using a subset of the data which was not utilized for development of the scoring system, and sensitivity and specificity were compared to previously validated in-hospital scoring systems applied in the pre-hospital setting. Results: 763 patients were included with 94 patients (12.3%) receiving early MT, defined as 4 units pRBC in 4 h or ED death. In-hospital models for predicting MT such as Assessment of Blood Consumption (ABC) or Shock Index (SI) have sensitivities and specificities of 46/85% and 94/79% respectively for early MTP utilization based on pre-hospital data. Pre-hospital variables found to be predictive of MT were used to develop the EMS-G (Extremity, Mechanism, Shock Index, GCS) score. This system assigns obvious ex- tremity injurye1-point, penetrating mechanism 2 points, shock index 0.9e2 points, GCS 8e3 points. A score of 3 or greater was chosen to maximize sensitivity and specificity for pre-hospital MT activation. EMS-G score based on pre-hospital report is 89% sensitive, 84% specific, with a PPV of 44% and NPV of 98% for early MT. Using this system, 25% of full and partial trauma team activations met criteria for pre-hospital MTP activation. Conclusion: The EMS-G Score has increased sensitivity and specificity compared to the ABC Score in the pre-hospital setting and appears more appropriate than shock index alone at predicting massive transfusion. This scoring system allows trauma centers to activate MTP prior to patient arrival to ensure early and appropriate blood product administration without blood product wastage. © 2019 Published by Elsevier Inc. Introduction The most common causes of death in the trauma population are hemorrhagic shock and traumatic brain injury. 1,2 The greatest risk for mortality due to uncontrolled hemorrhage occurs within the first hour of trauma, therefore, prompt recognition of the exsan- guinating patient and delivery of massive transfusion products while working to establish hemorrhage control, are paramount in improving outcomes. 3 To prevent hemodilution and correct coa- gulopathy in the exsanguinating patient, massive transfusion pro- tocols assist in expediting the delivery of appropriate blood products. 4,5 These protocols, once activated by a physician, allow for the quick mobilization and transfusion of packed red cells, * Corresponding author. Division of GI, Trauma, and Endocrine Surgery, Depart- ment of Surgery, University of Colorado Anschutz Medical Campus, 12631 E. 17th Ave, C313, Aurora, CO, 80045, USA. E-mail address: Franklin.Wright@cuanschutz.edu (F.L. Wright). Contents lists available at ScienceDirect The American Journal of Surgery journal homepage: www.americanjournalofsurgery.com https://doi.org/10.1016/j.amjsurg.2019.08.019 0002-9610/© 2019 Published by Elsevier Inc. The American Journal of Surgery xxx (xxxx) xxx Please cite this article as: Kovar A et al., The Extremity/Mechanism/Shock Index/GCS (EMS-G) score: A novel pre-hospital scoring system for early and appropriate MTP activation, The American Journal of Surgery, https://doi.org/10.1016/j.amjsurg.2019.08.019