A Bloody Mess: Management of Prehospital Hemorrhage
Andrew Thomas, MD
Acute hemorrhagic shock is a life-threatening condition that requires prompt recognition and management. Many of the advances in the medical management of traumatic hemorrhage are derived from military environments and have proven beneficial to civilian patients. Hemorrhage still carries a significant mortality risk – cited as the cause for 40% of adult trauma deaths occurring the first 24 hours after injury (Torres 2023). Trauma-induced coagulopathy further increases the mortality risk and should be addressed as an early component of resuscitation (Brohi 2003).
After achieving control of external hemorrhage with direct pressure, hemostatic gauze, and tourniquets, we look to other therapies for critically ill patients who display features of shock.
Prehospital Whole Blood
Despite recommendations in resuscitation guidelines for early administration of blood products for traumatic hemorrhagic shock, only 0.21% of hypotensive trauma patients receive any blood products pre-hospital (Hashmi 2021). Instead, most receive crystalloid fluids which increases the risk of ARDS, lowers platelet count and hematocrit, and increases the PTT and INR (Weycamp 2023).
A 2023 estimate of the scope of prehospital blood use in EMS systems identified 112 ground-based EMS agencies that have protocols for prehospital blood use. Additionally, prehospital blood administration is authorized by helicopter EMS agencies in all states (Randall 2023).
The barriers hindering the use of prehospital blood products include scope of practice limitations in some states, challenges to reimbursement, the need for education and training on the use of blood products, and the need for a system of delivery, storage, and re-collection of blood products.
O-positive Whole Blood may be the Solution.
As organizations consider the preferred blood product to administer, many have settled on low-titer O-positive whole blood as it is a balanced resuscitation of red blood cells, platelets, and clotting factors. It is more readily available than O-negative blood. While the potential for alloimmunization in females of child-bearing age has been considered, it is perceived as an acceptable risk when compared to the mortality risk of withholding or delaying blood products in hemorrhagic shock (Yazer 2019).
EMS organizations must be compliant with state and local regulatory and logistical matters as they source blood products. Additionally, they must implement a method for storing the blood products between 1°C -6°C in accordance with regulatory standards (Standards for blood banks and transfusion services 2020). Finally, the supply of blood products must be meticulously tracked so that unused products can be moved to a facility where they are likely to be utilized prior to expiring.
Ongoing lobbying efforts in Congress may help establish reimbursement for prehospital blood transfusion nationwide which will help provide financial support for this proven therapy.
Tranexamic Acid, Revisited
A recent meta-analysis examined randomized controlled trials (RCT) comparing tranexamic acid (TXA) to placebo for trauma patients with features of hemorrhagic shock. This found strong evidence of a moderate benefit, with a reduced mortality at 24 hours and at 1 month (Fouche 2024). In these studies, the baseline risk for 1-month mortality was 18% and the therapeutic benefit was a 1.8% reduction of mortality, suggesting a number needed to treat of 61. The potential harms of TXA – allergic reaction and thrombotic events – were not significantly present in the studies that comprised this meta-analysis, suggesting that the medication can be used safely.
TXA can be stored at room temperature and is compatible with dextrose, saline, and electrolytes. It can also be exceptionally cost effective – less than $6 per 1 gram dose at the time of publication of this blog (https://www.henryschein.com/).
But does it matter if the patient gets TXA earlier? Should it be given pre-hospital rather than after arriving to the hospital? It would seem so - one trial included in the meta-analysis revealed that 30-day mortality was lower when TXA was administered within 1 hour of injury compared to more than 1 hour (4.6% versus 7.6%; difference -3.0%; 95% CI -5.7% to -0.3%; P < .002). Additionally, pooled analysis of out-of-hospital TXA studies suggested 22% lower odds of death vs placebo with an NNT of 33 (95% CI 20-148). For patients treated in-hospital the odds of death are 9% less for TXA vs placebo with an NNT of 70 (95% CI 42-159).
TXA appears to be safe, inexpensive, easy to maintain and administer, and suggests more benefit when given earlier. For these reasons it should be considered in an EMS agency in treating hemorrhagic shock.
References
1. Torres CM, Kent A, Scantling D, Joseph B, Haut ER, Sakran JV. Association of Whole Blood With Survival Among Patients Presenting With Severe Hemorrhage in US and Canadian Adult Civilian Trauma Centers. JAMA Surg. 2023;158(5):532–540. doi:10.1001/jamasurg.2022.6978
2. Brohi, Karim BSc, FRCS, FRCA; Singh, Jasmin MB, BS, BSc; Heron, Mischa MRCP, FFAEM; Coats, Timothy MD, FRCS, FFAEM. Acute Traumatic Coagulopathy. The Journal of Trauma: Injury, Infection, and Critical Care 54(6):p 1127-1130, June 2003. | DOI: 10.1097/01.TA.0000069184.82147.06
3. Hashmi ZG, Chehab M, Nathens AB, et al. Whole truths but half the blood: Addressing the gap between the evidence and practice of pre-hospital and in-hospital blood product use for trauma resuscitation. Transfusion. 2021; 61: S348–S353. https://doi.org/10.1111/trf.16515
4. Weykamp MB, Stern KE, Brakenridge SC, Robinson BRH, Wade CE, Fox EE, Holcomb JB, O'Keefe GE. PREHOSPITAL CRYSTALLOID RESUSCITATION: PRACTICE VARIATION AND ASSOCIATIONS WITH CLINICAL OUTCOMES. Shock. 2023 Jan 1;59(1):28-33. doi: 10.1097/SHK.0000000000002039. Epub 2022 Nov 4. PMID: 36703275; PMCID: PMC9886338.
5. Randall Schaefer, DNP, e‐mail communication, October 2023.
6. Yazer MH, Delaney M, Doughty H, Dunbar NM, Al-Riyami AZ, Triulzi DJ, Watchko JF, Wood EM, Yahalom V, Emery SP. It is time to reconsider the risks of transfusing RhD negative females of childbearing potential with RhD positive red blood cells in bleeding emergencies. Transfusion. 2019 Dec;59(12):3794-3799. doi: 10.1111/trf.15569. Epub 2019 Oct 18. PMID: 31625172.
7. Standards for blood banks and transfusion services. 32nd ed. AABB; 2020. https://www.aabb.org/standards‐accreditation/standards/about‐aabb‐standards/standards‐library
8. Fouche, et al. Tranexamic Acid for Traumatic Injury in the Emergency Setting: A Systematic Review and Bias-Adjusted Meta-Analysis of Randomized Controlled Trials. Annals of Emergency Medicine. 2024 May;83(5)435-445. DOI: https://doi.org/10.1016/j.annemergmed.2023.10.004
9. Henry Schein medical supply website, “tranexamic acid 100mg/ml, 10ml vial, 10 per box”, Accessed May 2024. https://www.henryschein.com
About the Author
Dr. Andrew Thomas is a core faculty member at USF. He completed his residency training at ORMC in Orlando, FL and completed EMS Fellowship at Carolinas Medical Center in Charlotte, NC. He is the Co-Medical Director for Tampa Fire Rescue and serves as the Director for our PA Clerkship.