RESUMEN
BACKGROUND: Prehospital resuscitation with blood products is gaining popularity for patients with traumatic hemorrhage. The MEDEVAC trial demonstrated a survival benefit exclusively among patients who received blood or plasma within 15 minutes of air medical evacuation. In fast-paced urban EMS systems with a high incidence of penetrating trauma, mortality data based on the timing to first blood administration is scarce. We hypothesize a survival benefit in patients with severe hemorrhage when blood is administered within the first 15 minutes of EMS patient contact. METHODS: This was a retrospective analysis of a prospective database of prehospital blood (PHB) administration between 2021 and 2023 in an urban EMS system facing increasing rates of gun violence. Prehospital blood patients were compared with trauma registry controls from an era before prehospital blood utilization (2016-2019). Included were patients with penetrating injury and SBP ≤ 90 mm Hg at initial EMS evaluation that received at least one unit of blood product after injury. Excluded were isolated head trauma or prehospital cardiac arrest. Time to initiation of blood administration before and after PHB implementation and in-hospital mortality were the primary variables of interest. RESULTS: A total of 143 patients (PHB = 61, controls = 82) were included for analysis. Median age was 34 years with no difference in demographics. Median scene and transport intervals were longer in the PHB cohort, with a 5-minute increase in total prehospital time. Time to administration of first unit of blood was significantly lower in the PHB vs. control group (8 min vs. 27 min; p < 0.01). In-hospital mortality was lower in the PHB vs. control group (7% vs. 29%; p < 0.01). When controlling for patient age, NISS, tachycardia on EMS evaluation, and total prehospital time interval, multivariate regression revealed an independent increase in mortality by 11% with each minute delay to blood administration following injury (OR 1.11, 95%CI 1.04-1.19). CONCLUSION: Compared with patients with penetrating trauma and hypotension who first received blood after hospital arrival, resuscitation with blood products was started 19 minutes earlier after initiation of a PHB program despite a 5-minute increase in prehospital time. A survival for early PHB use was demonstrated, with an 11% mortality increase for each minute delay to blood administration. Interventions such as PHB may improve patient outcomes by helping capture opportunities to improve trauma resuscitation closer to the point of injury. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.
