Prehospital Mortality Due to Hemorrhagic Shock Remains High and Unchanged: A Summary of Current Civilian EMS Practices and New Military Changes

From shortages to solutions: Liquid plasma as a practical alternative to whole blood for prehospital trauma resuscitation

Trauma-induced hemorrhagic shock remains a leading cause of preventable mortality, necessitating timely and effective resuscitation strategies. While low-titer O whole blood (LTOWB) is the preferred choice for prehospital resuscitation due to its balanced composition and ease of use, overall widespread implementation is hindered by persistent supply chain issues and daily logistical challenges of access and deployment. Platelets, containing plasma as a component, are considered the next best alternative to LTOWB but are constrained by their short shelf life and ongoing scarcity, and ongoing storage compliance, rendering their use impractical. This review evaluates plasma-based alternatives, particularly liquid plasma (LP), as a viable and cost-effective substitute therapeutic modality. LP offers a 26-day refrigerated shelf life compared to the 5-day limit of thawed fresh frozen plasma (FFP) and eliminates the challenges associated with freezing and thawing while maintaining clinical efficacy. Preliminary economic analyses further underscore the advantages of LP, demonstrating reduced wastage and lower costs compared to LTOWB, especially when partnering with a hospital system. Acknowledging the barriers in implementing prehospital blood transfusion programs due to blood supply and costs, we advocate for emergency medical service (EMS) adoption of LP, highlighting its availability, comparable efficacy to LTOWB, and cost-effectiveness. Until LTOWB becomes more accessible, LP should be prioritized in prehospital care to optimize outcomes for trauma patients in hemorrhagic shock.

Blood far forward: A cross-sectional analysis of prehospital transfusion practices in the Canadian Armed Forces

BACKGROUND

Canadian Armed Forces (CAF) operate in environments that challenge patient care, especially trauma. Military personnel often find themselves in remote settings without conventional healthcare facilities. Treating traumatic injuries, particularly hemorrhagic shock, often necessitates prehospital blood transfusion. This study aims to present an overview of the current CAF prehospital transfusion practices. Furthermore, the study compared current and developing protocols against expert-recommended guidelines.

METHODS

A cross-sectional survey design was employed to describe and compare CAF prehospital blood transfusion practices and protocols against expert recommendations. Topics included protocols, equipment, and procedures. An online survey targeted medical leadership and providers within CAF, with data collected from August 15 to December 15, 2023. Results were summarized descriptively. This study received approval from the Unity Health Toronto Research Ethics Board (REB 23-087).

RESULTS

Units and teams with prehospital blood transfusion capabilities were contacted, achieving a 100 % response rate. Within CAF, Canadian Special Operations Forces Command (CANSOFCOM), Mobile Surgical Resuscitation Team (MSRT), and Canadian Medical Emergency Response Team (CMERT) possess these capabilities, established between 2013 and 2018. These programs are crucial for military operations. CAF has access to standard blood components, cold Leuko-Reduced Whole Blood (LrWB), and factor concentrates from Canadian Blood Services (CBS), available for both domestic and international missions given adequate planning and favorable conditions. Key findings indicate high adherence to recommended practices, some variability in the transfusion process, and potential benefits of standardizing prehospital transfusion practices.

CONCLUSIONS

This study provided insights into CAF's implementation of prehospital transfusion practices, highlighting high adherence to national expert recommendations and the importance of structured protocols in military prehospital trauma management.

IMPLICATIONS OF KEY FINDINGS

CAF's approach and adoption of prehospital transfusion protocols lay a strong foundation for managing trauma patients in remote settings and for expanding prehospital transfusion capabilities across CFHS deployed assets. Further research is needed to advance military trauma care by adapting prehospital blood transfusion to dynamic tactical landscapes and evolving technologies.

The Intersection of Trauma and Immunity: Immune Dysfunction Following Hemorrhage

Hemorrhagic shock is caused by rapid loss of a significant blood volume, which leads to insufficient blood flow and oxygen delivery to organs and tissues, resulting in severe physiological derangements, organ failure, and death. Physiologic derangements after hemorrhage are due in a large part to the body's strong inflammatory response, which leads to severe immune dysfunction, and secondary complications such as chronic immunosuppression, increased susceptibility to infection, coagulopathy, multiple organ failure, and unregulated inflammation. Immediate management of hemorrhagic shock includes timely control of the source of bleeding, restoring intravascular volume, preferably with whole blood, and prevention of ischemia and organ failure by optimizing tissue oxygenation. However, currently, there are no clinically effective treatments available that can stabilize the immune response to hemorrhage and reinstate homeostatic conditions. In this review, we will discuss what is known about immunologic dysfunction following hemorrhage and potential therapeutic strategies.

Phospholipid Nanoparticles: A Novel Colloid for Blood Volume Replacement, Reanimation, and Organ Protection in Hemorrhagic Shock

Background/Objectives: Exsanguination is a leading cause of preventable death in military and civilian settings due to extensive blood loss and hemorrhagic shock, which trigger systemic effects such as impaired tissue perfusion, hypoxia, inflammation, and multi-organ dysfunction. Standard resuscitation restores blood volume but fails to address critical aspects of hemorrhagic shock, including inflammation, coagulopathy, and reperfusion injury. To address these limitations, novel phospholipid nanoparticle (PNP)-based resuscitative fluids, VBI-S and VBI-1, were developed to modulate nitric oxide (NO) levels, improving hemodynamic stability, tissue oxygenation, and reducing inflammatory injury. This study assessed the potential of novel phospholipid nanoparticle fluids, VBI-S and VBI-1, as resuscitative agents for severe hemorrhagic shock by evaluating their ability to regulate nitric oxide, restore blood pressure, and mitigate ischemia-reperfusion injury. Methods: This study involved two phases with Sprague Dawley rats (n = 6 per group). Phase one, lasting 4 h, included four groups: blood, Ringer's lactate, VBI-S, and VBI-1. Phase two, lasting 12 h, comprised sham, blood, and VBI-1 groups. Under anesthesia, one femoral artery was catheterized for blood pressure monitoring, and blood withdrawal from the other induced apnea. Reanimation was performed using an intra-arterial infusion of shed blood, Ringer's lactate, VBI-S, or VBI-1. Tissue samples were analyzed histologically and for oxidative DNA damage via immunofluorescence. Chemiluminescence and rheology assessed nitric oxide interactions and viscosity. Data were analyzed using ANOVA. Results: VBI-1 and shed blood increased mean arterial pressure (MAP) from <10 mmHg to survivable levels sustained for 12 h, with VBI-1 showing significantly higher MAP at 3-4 h. Rats treated with Ringer's lactate died within 30 min. Histology revealed reduced organ damage in VBI-1-treated rats compared to shed blood. Immunohistochemistry indicated significantly less oxidative DNA damage (p < 0.001) in VBI-1-treated rats. VBI-1 exhibited superior viscosity and nitric oxide binding. Conclusions: VBI-1 demonstrates strong potential as a resuscitative fluid, offering blood pressure restoration, reduced oxidative damage, and enhanced tissue perfusion, with significant implications for use in resource-limited and pre-hospital settings.

Advanced Critical Care Techniques in the Field

Critical care principles and techniques continue to hold promise for improving patient outcomes in time-dependent diseases encountered by emergency medical services such as cardiac arrest, acute ischemic stroke, and hemorrhagic shock. In this review, the authors discuss several current and evolving advanced critical care modalities, including extracorporeal cardiopulmonary resuscitation, resuscitative endovascular occlusion of the aorta, prehospital thrombolytics for acute ischemic stroke, and low-titer group O whole blood for trauma patients. Two important critical care monitoring technologies-capnography and ultrasound-are also briefly discussed.

Faster refill in an urban emergency medical services system saves lives: A prospective preliminary evaluation of a prehospital advanced resuscitative care bundle

INTRODUCTION

Military experience has demonstrated mortality improvement when advanced resuscitative care (ARC) is provided for trauma patients with severe hemorrhage. The benefits of ARC for trauma in civilian emergency medical services (EMS) systems with short transport intervals are still unknown. We hypothesized that ARC implementation in an urban EMS system would reduce in-hospital mortality.

METHODS

This was a prospective analysis of ARC bundle administration between 2021 and 2023 in an urban EMS system with 70,000 annual responses. The ARC bundle consisted of calcium, tranexamic acid, and packed red blood cells via a rapid infuser. Advanced resuscitative care patients were compared with trauma registry controls from 2016 to 2019. Included were patients with a penetrating injury and systolic blood pressure ≤90 mm Hg. Excluded were isolated head trauma or prehospital cardiac arrest. In-hospital mortality was the primary outcome of interest.

RESULTS

A total of 210 patients (ARC, 61; controls, 149) met the criteria. The median age was 32 years, with no difference in demographics, initial systolic blood pressure or heart rate recorded by EMS, or New Injury Severity Score between groups. At hospital arrival, ARC patients had lower median heart rate and shock index than controls ( p ≤ 0.03). Fewer patients in the ARC group required prehospital advanced airway placement ( p < 0.001). Twenty-four-hour and total in-hospital mortality were lower in the ARC group ( p ≤ 0.04). Multivariable regression revealed an independent reduction in in-hospital mortality with ARC (odds ratio, 0.19; 95% confidence interval, 0.05-0.68; p = 0.01).

CONCLUSION

Early ARC in a fast-paced urban EMS system is achievable and may improve physiologic derangements while decreasing patient mortality. Advanced resuscitative care closer to the point of injury warrants consideration.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Breaking barriers in trauma research: A narrative review of opportunities to leverage veterinary trauma for accelerated translation to clinical solutions for pets and people

Trauma is a common cause of morbidity and mortality in humans and companion animals. Recent efforts in procedural development, training, quality systems, data collection, and research have positively impacted patient outcomes; however, significant unmet need still exists. Coordinated efforts by collaborative, translational, multidisciplinary teams to advance trauma care and improve outcomes have the potential to benefit both human and veterinary patient populations. Strategic use of veterinary clinical trials informed by expertise along the research spectrum (i.e., benchtop discovery, applied science and engineering, large laboratory animal models, clinical veterinary studies, and human randomized trials) can lead to increased therapeutic options for animals while accelerating and enhancing translation by providing early data to reduce the cost and the risk of failed human clinical trials. Active topics of collaboration across the translational continuum include advancements in resuscitation (including austere environments), acute traumatic coagulopathy, trauma-induced coagulopathy, traumatic brain injury, systems biology, and trauma immunology. Mechanisms to improve funding and support innovative team science approaches to current problems in trauma care can accelerate needed, sustainable, and impactful progress in the field. This review article summarizes our current understanding of veterinary and human trauma, thereby identifying knowledge gaps and opportunities for collaborative, translational research to improve multispecies outcomes. This translational trauma group of MDs, PhDs, and DVMs posit that a common understanding of injury patterns and resulting cellular dysregulation in humans and companion animals has the potential to accelerate translation of research findings into clinical solutions.

Tourniquet Use in the Prehospital Setting

PURPOSE

Tourniquets are a mainstay of life-saving hemorrhage control. The US military has documented the safety and effectiveness of tourniquet use in combat settings. In civilian settings, events such as the Boston Marathon bombing and mass shootings show that tourniquets are necessary and life-saving entities that must be used correctly and whenever indicated. Much less research has been done on tourniquet use in civilian settings compared to military settings. The purpose of this study is to describe the prehospital use of tourniquets in a regional EMS system served by a single trauma center.

METHODS

All documented cases of prehospital tourniquet use from 2015 to 2020 were identified via a search of EMS, emergency department, and inpatient records, and reviewed by the lead investigator. The primary outcomes were duration of tourniquet placement, success of hemorrhage control, and complications; secondary outcomes included time of day (by EMS arrival time), transport interval, extremity involved, who placed/removed the tourniquet, and mechanism of injury.

RESULTS

Of 182 patients with 185 tourniquets applied, duration of application was available for 52, with a median (IQR) of 43 (56) minutes. Hemorrhage control was achieved in all but two cases (96%). Three cases (5.8%) required more than one tourniquet. Complications included five cases of temporary paresthesia, one case of ecchymosis, two cases of fasciotomy, and two cases of compression nerve injury. The serious complication rate was 7.7% (4/52). Time of day was daytime (08:01-16:00) = 15 (31.9%), evening (16:01-00:00) = 27 (57.4%), and night (00:01- 08:00) = 5 (10.6%). The median transport interval was 22 (IQR 5] minutes. The limbs most often injured were the left and right upper extremities (15 each). EMS clinicians and police officers were most often the tourniquet placers. Common mechanisms of injury included gunshot wounds, motorcycle accidents, and glass injuries.

CONCLUSION

Tourniquets used in the prehospital setting have a high rate of hemorrhage control and a low rate of complications.

An All-In-One Transient Theranostic Platform for Intelligent Management of Hemorrhage

Developing theranostic devices to detect bleeding and effectively control hemorrhage in the prehospital setting is an unmet medical need. Herein, an all-in-one theranostic platform is presented, which is constructed by sandwiching silk fibroin (SF) between two silver nanowire (AgNW) based conductive electrodes to non-enzymatically diagnose local bleeding and stop the hemorrhage at the wound site. Taking advantage of the hemostatic property of natural SF, the device is composed of a shape-memory SF sponge, facilitating blood clotting, with ≈82% reduction in hemostatic time in vitro as compared with untreated blood. Furthermore, this sandwiched platform serves as a capacitive sensor that can detect bleeding and differentiate between blood and other body fluids (i.e., serum and water) via capacitance change. In addition, the AgNW electrode endows anti-infection efficiency against Escherichia coli and Staphylococcus aureus. Also, the device shows excellent biocompatibility and gradually biodegrades in vivo with no major local or systemic inflammatory responses. More importantly, the theranostic platform presents considerable hemostatic efficacy comparable with a commercial hemostat, Dengen, in rat liver bleeding models. The theranostic platform provides an unexplored strategy for the intelligent management of hemorrhage, with the potential to significantly improve patients' well-being through the integration of diagnostic and therapeutic capabilities.

Ex vivo hemostatic and immuno-inflammatory profiles of freeze-dried plasma

BACKGROUND

Hemorrhage is a leading cause of preventable death in civilian and military trauma. Freeze-dried plasma is promising for hemostatic resuscitation in remote prehospital settings, given its potential benefits in reducing blood loss and mortality, long storage at ambient temperatures, high portability, and rapid reconstitution for transfusion in austere environments. Here we assess the ex vivo characteristics of a novel Terumo's freeze-dried plasma product (TFDP).

STUDY DESIGN AND METHODS

Rotational thromboelastometry (ROTEM) tests (INTEM, EXTEM, and FIBTEM) were conducted on plasma samples at 37°C with a ROTEM delta-machine using standard reagents and procedures. The following samples were analyzed: pooled plasma to produce TFDP, TFDP reconstituted, and stored immediately at -80°C, reconstituted TFDP stored at 4°C for 24 h and room temperature (RT) for 4 h before freezing at -80°C. Analysis of plasma concentrations of selected cytokines, chemokines, and vascular molecules was performed using a multiplex immunoassay system. One-way ANOVA with post hoc tests assessed differences in hemostatic and inflammatory properties.

RESULTS

No significant differences in ROTEM variables (coagulation time [CT], clot formation time, α-angle, maximum clot firmness, and lysis index 30) between the TFDP-producing plasma and reconstituted TFDP samples were observed. Compared to control plasma, reconstituted TFDP stored at 4°C for 24 h or RT for 4 h showed a longer INTEM CT. Levels of immuno-inflammatory mediators were similar between frozen plasma and TFDP.

CONCLUSIONS

TFDP is equivalent to frozen plasma with respect to global hemostatic and immuno-inflammatory mediator profiles. Further investigations of TFDP in trauma-induced coagulopathy models and bleeding patients are warranted.

Prehospital aortic blood flow control techniques for non-compressible traumatic hemorrhage

Non-compressible hemorrhage in the junctional areas and torso could be life-threatening and its prehospital control remains extremely challenging. The aim of this review was to compare commonly used techniques for the control of non-compressible hemorrhage in prehospital settings, and thereby provide evidence for further improvements in emergency care of traumatic injuries. Three techniques were reviewed including external aortic compression (EAC), abdominal aortic junctional tourniquet (AAJT), and resuscitative endovascular balloon occlusion of the aorta (REBOA). In prehospital settings, all three techniques have demonstrated clinical effectiveness for the control of severe hemorrhage. EAC is a cost- and equipment-free, easy-to-teach, and immediately available technique. In contrast, AAJT and REBOA are expensive and require detailed instructions or systematic training. Compared with EAC, AAJT and REBOA have greater potentials in the management of traumatic hemorrhage. AAJT can be used not only in the junctional areas but also in pelvic and bilateral lower limb injuries. However, both AAJT and REBOA should be used for a limited time (less than 1 hour) due to possible consequences of ischemia and reperfusion. Compared with EAC and AAJT, REBOA is invasive, requiring femoral arterial access and intravascular guidance and inflation. Mortality from non-compressible hemorrhage could be reduced through the prehospital application of aortic blood flow control techniques. EAC should be considered as the first-line choice for many non-compressible injuries that cannot be managed with conventional junctional tourniquets. In comparison, AAJT or REBOA is recommended for better control of the aorta blood flow in prehospital settings. Although these three techniques each have advantages, their use in trauma is not widespread. Future studies are warranted to provide more data about their safety and efficacy.

Size matters: first-in-human study of a novel 4 French REBOA device

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging technique used for non-compressible torso hemorrhage. However, its current use continues to be limited and there is a need for a simple, fast, and low profile REBOA device. Our objective was to evaluate the feasibility of a novel 4 French REBOA device called the COBRA-OS (Control of Bleeding, Resuscitation, Arterial Occlusion System).

Methods

This study is the first-in-human feasibility trial of the COBRA-OS. Due to the difficulty of trialing the device in the trauma setting, we performed a feasibility study using organ donors (due to the potential usefulness of the COBRA-OS for normothermic regional perfusion) after neurological determination of death (NDD) prior to organ retrieval. Bilateral 4 French introducer sheaths were placed in both femoral arteries and the COBRA-OS was advanced up the right side and deployed in the thoracic aorta (Zone 1). Once aortic occlusion was confirmed via the left-sided arterial line, the device was deflated, moved to the infrarenal aorta (Zone 3), and redeployed.

Results

A total of 7 NDD organ donors were entered into the study, 71% men, with a mean age 46.6 years (range 26 to 64). The COBRA-OS was able to occlude the aorta in Zones 1 and 3 in all patients. The mean time of placing a 4 French sheath was 47.7 seconds (n=13, range 28 to 66 seconds). The mean time from skin to Zone 1 aortic occlusion was 70.1 seconds (range 58 to 105 seconds); mean balloon volumes were 15 mL for Zone 1 (range 13 to 20 mL) and 9 mL for Zone 3 (range 6 to 15 mL); there were no complications and visual inspection of the aorta in all patients revealed no injury.

Discussion

The COBRA-OS is a novel 4 French REBOA device that has demonstrated fast and safe aortic occlusion in this first-in-human feasibility study.

Level of evidence

Level V, therapeutic.

Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA): update and insights into current practices and future directions for research and implementation

Background

In this review, we assess the state of Resuscitative Endovascular Occlusion of the Aorta (REBOA) today with respect to out-of-hospital (OOH) vs. inhospital (H) use in blunt and penetrating trauma, as well as discuss areas of promising research that may be key in further advancement of REBOA applications.

Methods

To analyze the trends in REBOA use, we conducted a review of the literature and identified articles with human or animal data that fit the respective inclusion and exclusion criteria. In separate tables, we compiled data extracted from selected articles in categories including injury type, zone and duration of REBOA, setting in which REBOA was performed, sample size, age, sex and outcome. Based on these tables as well as more detailed review of some key cases of REBOA usage, we assessed the current state of REBOA as well as coagulation and histological disturbances associated with its usage. All statistical tests were 2-sided using an alpha=0.05 for significance. Analysis was done using SAS 9.5 (Cary, NC). Tests for significance was done with a t-test for continuous data and a Chi Square Test for categorical data.

Results

In a total of 44 cases performed outside of a hospital in both military and civilian settings, the overall survival was found to be 88.6%, significantly higher than the 50.4% survival calculated from 1,807 cases of REBOA performed within a hospital (p<.0001). We observe from human data a propensity to use Zone I in penetrating trauma and Zone III in blunt injuries. We observe lower final metabolic markers in animal studies with shorter REBOA time and longer follow-up times.

Conclusions

Further research related to human use of REBOA must be focused on earlier initiation of REBOA after injury which may depend on development of rapid vascular access devices and techniques more so than on any new improvements in REBOA. Future animal studies should provide detailed multisystem organ assessment to accurately define organ injury and metabolic burden associated with REBOA application. Overall, animal studies must involve realistic models of injury with severe clinical scenarios approximating human trauma and exsanguination, especially with long-term follow-up after injury.