The effects of prehospital plasma on patients with injury: a prehospital plasma resuscitation

Are trauma centers penalized for improved prehospital resuscitation?: The effect of prehospital transfusion on arrival vitals and predicted mortality

BACKGROUND

Prediction models for survival in trauma rely on arrival vital signs to generate survival probabilities. Hospitals are benchmarked on expected and observed outcomes. Prehospital blood (PB) transfusion has been shown to improve mortality, which may affect survival prediction modeling. We hypothesize that the use of PB increases the predicted survival derived from probability models compared with non-blood-based resuscitation.

METHODS

All adult trauma patients presenting to a level 1 trauma center requiring emergency release blood transfusion from January 2017 to December 2021 were reviewed. Patients were grouped into those receiving PB or those who did not (no PB). Prehospital Trauma and Injury Severity Score (TRISS) and shock index were compared with those at presentation to hospital. Univariate and multivariate regressions were performed to identify factors associated with changes in survival probability at presentation.

RESULTS

In total, 2117 patients were reviewed (PB, 1,011; no PB, 1,106). Patients receiving PB were younger (35 vs. 40 years, p < 0.001), more likely to have blunt mechanism (71% vs. 65%, p = 0.002), and more severely injured (Injury Severity Score, 27 vs. 25; p < 0.001) and had higher rates of prehospital hypotension (44% vs. 19%, p < 0.001) and shock index (1.10 vs. 0.87, p < 0.001). Upon arrival, PB patients had lower rates of ED hypotension (34% vs. 39%, p = 0.01), and significant improvements in arrival TRISS scores (+0.09 vs. -0.02, p < 0.001) and shock index (+0.10 vs. -0.07, p < 0.001) compared with prehospital. On multivariate analysis, PB was associated with a threefold increase in unexpected survivors (odds ratio, 3.28; 95% confidence interval, 2.23-4.60).

CONCLUSION

The use of PB was associated with improved probability of survival and an increase in unexpected survivors. Applying TRISS and shock index at hospital arrival does not account for en route hemostatic resuscitation, causing patients to arrive with improved vitals despite severity of injury. Caution should be used when implementing survival probability calculations using arrival vitals in centers with prehospital transfusion capability.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Efficacy and Safety of Prehospital Blood Transfusion in Traumatized Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Approximately five million individuals have traumatic injuries annually. Implementing prehospital blood-component transfusion (PHBT), encompassing packed red blood cells (p-RBCs), plasma, or platelets, facilitates early hemostatic volume replacement following trauma. The lack of uniform PHBT guidelines persists, relying on diverse parameters and physician experience.

AIM

This study aims to evaluate the efficacy of various components of PHBT, including p-RBCs and plasma, on mortality and hematologic-related outcomes in traumatic patients.

METHODS

A comprehensive search strategy was executed to identify pertinent literature comparing the transfusion of p-RBCs, plasma, or a combination of both with standard resuscitation care in traumatized patients. Eligible studies underwent independent screening, and pertinent data were systematically extracted. The analysis employed pooled risk ratios (RR) for dichotomous outcomes and mean differences (MD) for continuous variables, each accompanied by their respective 95% confidence intervals (CI).

RESULTS

Forty studies were included in the qualitative analysis, while 26 of them were included in the quantitative analysis. Solely P-RBCs alone or combined with plasma showed no substantial effect on 24-hour or long-term mortality (RR = 1.13; 95% CI, 0.68 - 1.88; P = .63). Conversely, plasma transfusion alone exhibited a 28% reduction in 24-hour mortality with a RR of 0.72 (95% CI, 0.53 - 0.99; P = .04). In-hospital mortality and length of hospital stay were mostly unaffected by p-RBCs or p-RBCs plus plasma, except for a notable three-day reduction in length of hospital stay with p-RBCs alone (MD = -3.00; 95% CI, -5.01 to -0.99; P = .003). Hematological parameter analysis revealed nuanced effects, including a four-unit increase in RBC requirements with p-RBCs (MD = 3.95; 95% CI, 0.69 - 7.21; P = .02) and a substantial reduction in plasma requirements with plasma transfusion (MD = -0.73; 95% CI, -1.28 to -0.17; P = .01).

CONCLUSION

This study revealed that plasma transfusion alone was associated with a substantial decrease in 24-hour mortality. Meanwhile, p-RBCs alone or combined with plasma did not significantly impact 24-hour or long-term mortality. In-hospital mortality and length of hospital stay were generally unaffected by p-RBCs or p-RBCs plus plasma, except for a substantial reduction in length of hospital stay with p-RBCs alone.

Resuscitation and Care in the Trauma Bay

Start balanced resuscitation early (pre-hospital if possible), either in the form of whole blood or 1:1:1 ratio. Minimize resuscitation with crystalloid to minimize patient morbidity and mortality. Trauma-induced coagulopathy can be largely avoided with the use of balanced resuscitation, permissive hypotension, and minimized time to hemostasis. Using protocolized "triggers" for massive and ultramassive transfusion will assist in minimizing delays in transfusion of products, achieving balanced ratios, and avoiding trauma induced coagulopathy. Once "audible" bleeding has been addressed, further blood product resuscitation and adjunct replacement should be guided by viscoelastic testing. Early transfusion of whole blood can reduce patient morbidity, mortality, decreases donor exposure, and reduces nursing logistics during transfusions. Adjuncts to resuscitation should be guided by laboratory testing and carefully developed, institution-specific guidelines. These include empiric calcium replacement, tranexamic acid (or other anti-fibrinolytics), and fibrinogen supplementation.

Prehospital Plasma Transfusion: What Does the Literature Show?

Background

Early initiation of blood products transfusion after injury has been associated with improved patient outcomes following traumatic injury. The ability to transfuse patients' plasma in the prehospital setting provides a prime opportunity to begin resuscitation with blood products earlier and with a more balanced plasma: RBC ratio than what has traditionally been done. Published studies on the use of prehospital plasma show a complex relationship between its use and improved survival.

Summary

Examination of the literature shows that there may be a mortality benefit from the use of prehospital plasma, but that it may be limited to certain subgroups of trauma patients. The likelihood of realizing these survival benefits appears to be predicted by several factors including the type of injury, length of transport time, presence of traumatic brain injury, and total number of blood products transfused, whether the patient required only a few products or a massive transfusion. When taken as a whole the evidence appears to show that prehospital plasma may have a mortality benefit that is most clearly demonstrated in patients with blunt injuries, moderate transfusion requirements, traumatic brain injury, and/or transport time greater than 20 min, as well as those who demonstrate a certain cytokine expression profile.

Key Messages

The evidence suggests that a targeted use of prehospital plasma will most likely maximize the benefits from the use of this limited resource. It is also possible that prehospital plasma may best be provided through whole blood as survival benefits were greatest in patients who received both prehospital plasma and RBCs.

Validation of a Point-of-Care Analyzer for Determining Anticoagulation Status During Air Transport

OBJECTIVE

We evaluated a point-of-care prothrombin time (PT)/international normalized ratio (INR) cartridge-based analyzer for its feasibility, accuracy, and value in critical care air transport.

METHODS

In this prospective study, blood samples from 10 randomly selected adult patients were tested with the cartridge during transport to determine feasibility. The cartridge results were compared with the laboratory results for the same samples. Similarly, blood samples from an additional 20 randomly selected adult patients were tested to determine test accuracy. A chart review identified 110 adult patients with PT/INR cartridge results to determine the clinical value of those results.

RESULTS

Data from the first group of 10 patients showed that vibration did not affect use of the cartridge. The average bias between the 2 testing methods was 0.0 INR units. A comparison of the PT/INR cartridge results and the laboratory results from the group of 20 patients showed that 73% of the cartridge values were within 0.2 of the laboratory values, 83% were within 0.4, and 93% were within 0.6. Of the 110 patients whose charts showed PT/INR cartridge results, 23% received blood products (45 trauma patients and 65 medical patients).

CONCLUSION

The PT/INR cartridge withstands the rigors of rotor wing transport and provides accurate, valuable results for making clinical decisions.

A scoping review of worldwide studies evaluating the effects of prehospital time on trauma outcomes

BACKGROUND

Annually, over 1 billion people sustain traumatic injuries, resulting in over 900,000 deaths in Africa and 6 million deaths globally. Timely response, intervention, and transportation in the prehospital setting reduce morbidity and mortality of trauma victims. Our objective was to describe the existing literature evaluating trauma morbidity and mortality outcomes as a function of prehospital care time to identify gaps in literature and inform future investigation.

MAIN BODY

We performed a scoping review of published literature in MEDLINE. Results were limited to English language publications from 2009 to 2020. Included articles reported trauma outcomes and prehospital time. We excluded case reports, reviews, systematic reviews, meta-analyses, comments, editorials, letters, and conference proceedings. In total, 808 articles were identified for title and abstract review. Of those, 96 articles met all inclusion criteria and were fully reviewed. Higher quality studies used data derived from trauma registries. There was a paucity of literature from studies in low- and middle-income countries (LMIC), with only 3 (3%) of articles explicitly including African populations. Mortality was an outcome measure in 93% of articles, predominantly defined as "in-hospital mortality" as opposed to mortality within a specified time frame. Prehospital time was most commonly assessed as crude time from EMS dispatch to arrival at a tertiary trauma center. Few studies evaluated physiologic morbidity outcomes such as multi-organ failure.

CONCLUSION

The existing literature disproportionately represents high-income settings and most commonly assessed in-hospital mortality as a function of crude prehospital time. Future studies should focus on how specific prehospital intervals impact morbidity outcomes (e.g., organ failure) and mortality at earlier time points (e.g., 3 or 7 days) to better reflect the effect of early prehospital resuscitation and transport. Trauma registries may be a tool to facilitate such research and may promote higher quality investigations in Africa and LMICs.

Blood product transfusion during air medical transport: A needs assessment

Objectives

Early administration of blood products to patients with hemorrhagic shock has a positive impact on morbidity and mortality. Smaller hospitals may have limited supply of blood, and air medical systems may not carry blood. The primary outcome is to quantify the number of patients meeting established physiologic criteria for blood product administration and to identify which patients receive and which ones do not receive it due to lack of availability locally.

Methods

Electronic patient care records were used to identify a retrospective cohort of patients undergoing emergent air medical transport in Ontario, Canada, who are likely to require blood. Presenting problems for blood product administration were identified. Physiologic data were extracted with criteria for transfusion used to identify patients where blood product administration is indicated.

Results

There were 11,520 emergent patient transports during the study period, with 842 (7.3%) where blood product administration was considered. Of these, 290 met established physiologic criteria for blood products, with 167 receiving blood, of which 57 received it at a hospital with a limited supply. The mean number of units administered per patient was 3.5. The remaining 123 patients meeting criteria did not receive product because none was unavailable.

Conclusion

Indications for blood product administration are present in 2.5% of patients undergoing time-sensitive air medical transport. Air medical services can enhance access to potentially lifesaving therapy in patients with hemorrhagic shock by carrying blood products, as blood may be unavailable or in limited supply locally in the majority of patients where it is indicated.

Delta Systolic Blood Pressure (SBP) Can be a Stronger Predictor of Mortality Than Pre-Aortic Occlusion SBP in Non-Compressible Torso Hemorrhage; an Abotrauma and AORTA Analysis

BACKGROUND

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is becoming a standardized adjunct for the management in patients with severe non-compressible torso hemorrhage (NCTH). Although guidelines have been developed to help with the best indications for REBOA utilization, no studies have addressed the significance of change in systolic blood pressure (ΔSBP) after REBOA insufflation. We hypothesized that ΔSBP would predict mortality in patients with NCTH and have utility as a surrogate marker for hemorrhage status.

STUDY DESIGN

This was an international, multicenter retrospective review of all patients managed with REBOA from the ABOTrauma Registry and the AORTA database. ΔSBP was defined as the difference between pre- and post-REBOA insertion SBP. Based on post-insertion SBP, patient hemorrhage status was categorized as responder or non-responder. A non-responder was defined as a hypotensive patient with systolic blood pressure (SBP) < 90 mmHg after REBOA placement with full aortic occlusion. Significance was set at P < 0.05.

RESULTS

A total of 524 patients with NCTH were included. Most (74%) were male, 77% blunt injured with a median (IQR) age of 40 (27 - 58) years and ISS 34 (25 - 45). Overall mortality was 51.0%. 20% of patients were classified as non-responders. Demographic and injury descriptors did not differ between groups. Mortality was significantly higher in non-responders vs responders (64% vs 46%, respectively; P = 0.001). Non-responders had lower median pre-insertion SBP (50mmHg vs 67mmHg; P < 0.001) and lower ΔSBP (20mmHg vs 48mmHg; P < 0.001).

CONCLUSION

REBOA non-responders present and remain persistently hypotensive and are more likely to die than responders, indicating a potential direct correlation between ΔSBP as a surrogate marker of hemorrhage volume status and mortality. Future prospective studies will need to further elucidate the impact of Damage Control Resuscitation efforts on ΔSBP and mortality.

Pre-hospital transfusion of red blood cells. Part 1: A scoping review of current practice and transfusion triggers

OBJECTIVES

The primary aim of this scoping review is to describe the current use of pre-hospital transfusion of red blood cells (PHTRBC) and to evaluate criteria used to initiate PHTRBC. The effects on patients' outcomes will be reviewed in Part 2.

BACKGROUND

Haemorrhage is a preventable cause of death in trauma patients, and transfusion of red blood cells is increasingly used by Emergency Medical Services (EMS) for damage control resuscitation. However, there are no guidelines and little consensus on when to initiate PHTRBC.

METHODS

PubMed and Web of Science were searched through January 2019; 71 articles were included.

RESULTS

Transfusion triggers vary widely and involve vital signs, clinical signs of poor tissue perfusion, point of care measurements and pre-hospital ultrasound imaging. In particular, hypotension (most often defined as systolic blood pressure ≤ 90 mmHg), tachycardia (most often defined as heart rate ≥ 120/min), clinical signs of poor perfusion (eg, prolonged capillary refill time or changes in mental status) and injury type (ie, penetrating wounds) are common pre-hospital transfusion triggers.

CONCLUSIONS

PHTRBC is increasingly used by Emergency Medical Services, but guidelines on when to initiate transfusion are lacking. We identified the most commonly used transfusion criteria, and these findings may provide the basis for consensus-based pre-hospital transfusion protocols.

Pre-hospital transfusion of red blood cells. Part 2: A systematic review of treatment effects on outcomes

The primary aim of this systematic review is to describe the effects of prehospital transfusion of red blood cells (PHTRBC) on patient outcomes. Damage control resuscitation attempts to prevent death through haemorrhage in trauma patients. In this context, transfusion of red blood cells is increasingly used by emergency medical services (EMS). However, evidence on the effects on outcomes is scarce. PubMed and Web of Science were searched through January 2019; 55 articles were included. No randomised controlled studies were identified. While several observational studies suggest an increased survival after PHTRBC, consistent evidence for beneficial effects of PHTRBC on survival was not found. PHTRBC appears to improve haemodynamic parameters, but there is no evidence that shock on arrival to hospital is averted, nor of an association with trauma induced coagulopathy or with length of stay in hospitals or intensive care units. In conclusion, PHTRBC is increasingly used by EMS, but there is no strong evidence for effects of PHTRBC on mortality. Further research with study designs that allow causal inferences is required for more conclusive evidence. The combination of PHTRBC with plasma, as well as the use of individualised transfusion criteria, may potentially show more benefits and should be thoroughly investigated in the future. The review was registered at Prospero (CRD42018084658).

What is the impact of prehospital blood product administration for patients with catastrophic haemorrhage: an integrative review

INTRODUCTION

Catastrophic haemorrhage is recognised as the leading cause of preventable death in trauma and is also prevalent in medical and other surgical aetiology. Prehospital blood product transfusion is increasingly available for both military and civilian emergency teams. Hospitals have well-established massive transfusion protocols for the resuscitation of this patient group, however the use and impact in the prehospital field is less understood.

AIM

To identify and evaluate the current knowledge surrounding prehospital blood product administration for patients with catastrophic haemorrhage.

METHODS

The integrative review method included systematic searching of online databases Medline, EMBASE, SCOPUS and CINAHL alongside hand-searching for primary research articles published prior to 19 November 2018. Papers were included if the population studied patients with catastrophic haemorrhage who received prehospital transfusion of blood products. The level of evidence and quality was evaluated using the NHMRC hierarchy of evidence. All identified full text articles were reviewed by all authors.

RESULTS

Twenty-two papers were included in the final analysis, including both civilian (16) and military (6) practice. The earliest publication for prehospital transfusion was 1999, with increasing prevalence in recent years. Findings were extracted and into two main categories; (1) transfusion processes included team staffing, product selection, and criteria for transfusion and (2) transfusion outcomes; transfusion safety, haemoglobin, hospital intervention and mortality.

DISCUSSION

The level of evidence specific to prehospital blood product transfusion is low, with predominantly retrospective methods and rarely sufficient sample sizes to reach statistical significance. Prehospital research is challenged by clinical and logistical variability preventing accurate cohort matching, sample sizes and inconsistent data collection. Evaluation of prehospital transfusion in isolation is also particularly problematic as multiple factors and developments in clinical practice affect patient outcomes and all samples were subject to survival bias. Conclusion The volume and strength of the available evidence prevents accurate evaluation of the intervention and definitive practice recommendations however prehospital transfusion is shown to be logistically achievable and without serious incident. The reviewed evidence broadly supports the translation of recent in-hospital studies, such as PROMTT and PROPPR. Further research specific to prehospital practice is required to guide the development of evidence-based protocols.

Plasma Transfusion: History, Current Realities, and Novel Improvements

Traumatic hemorrhage is the leading cause of preventable death after trauma. Early transfusion of plasma and balanced transfusion have been shown to optimize survival, mitigate the acute coagulopathy of trauma, and restore the endothelial glycocalyx. There are a myriad of plasma formulations available worldwide, including fresh frozen plasma, thawed plasma, liquid plasma, plasma frozen within 24 h, and lyophilized plasma (LP). Significant equipoise exists in the literature regarding the optimal plasma formulation. LP is a freeze-dried formulation that was originally developed in the 1930s and used by the American and British military in World War II. It was subsequently discontinued due to risk of disease transmission from pooled donors. Recently, there has been a significant amount of research focusing on optimizing reconstitution of LP. Findings show that sterile water buffered with ascorbic acid results in decreased blood loss with suppression of systemic inflammation. We are now beginning to realize the creation of a plasma-derived formulation that rapidly produces the associated benefits without logistical or safety constraints. This review will highlight the history of plasma, detail the various types of plasma formulations currently available, their pathophysiological effects, impacts of storage on coagulation factors in vitro and in vivo, novel concepts, and future directions.

Prehospital Blood Product Resuscitation for Trauma: A Systematic Review

Introduction:

Administration of high ratios of plasma to packed red blood cells is a routine practice for in-hospital trauma resuscitation. Military and civilian emergency teams are increasingly carrying prehospital blood products (PHBP) for trauma resuscitation. This study systematically reviewed the clinical literature to determine the extent to which the available evidence supports this practice.

Methods:

Bibliographic databases and other sources were searched to July 2015 using keywords and index terms related to the intervention, setting, and condition. Standard systematic review methodology aimed at minimizing bias was used for study selection, data extraction, and quality assessment (protocol registration PROSPERO: CRD42014013794). Synthesis was mainly narrative with random effects model meta-analysis limited to mortality outcomes.

Results:

No prospective comparative or randomized studies were identified. Sixteen case series and 11 comparative studies were included in the review. Seven studies included mixed populations of trauma and non-trauma patients. Twenty-five of 27 studies provided only very low quality evidence. No association between PHBP and survival was found (OR for mortality: 1.29, 95% CI: 0.84–1.96, P = 0.24). A single study showed improved survival in the first 24 h. No consistent physiological or biochemical benefit was identified, nor was there evidence of reduced in-hospital transfusion requirements. Transfusion reactions were rare, suggesting the short-term safety of PHBP administration.

Conclusions:

While PHBP resuscitation appears logical, the clinical literature is limited, provides only poor quality evidence, and does not demonstrate improved outcomes. No conclusions as to efficacy can be drawn. The results of randomized controlled trials are awaited.

Initiation and Termination of Massive Transfusion Protocols: Current Strategies and Future Prospects

The advent of massive transfusion protocols (MTP) has had a significant positive impact on hemorrhaging trauma patient morbidity and mortality. Nevertheless, societal MTP guidelines and individual MTPs at academic institutions continue to circulate opposing recommendations on topics critical to MTPs. This narrative review discusses up-to-date information on 2 such topics, the initiation and termination of an MTP. The discussion for each begins with a review of the recommendations and supporting literature presented by MTP guidelines from 3 prominent societies, the American Society of Anesthesiologists, the American College of Surgeons, and the task force for Advanced Bleeding Care in Trauma. This is followed by an in-depth analysis of the main components within those recommendations. Societal recommendations on MTP initiation in hemorrhaging trauma patients emphasize the use of retrospectively validated massive transfusion (MT) prediction score, specifically, the Assessment of Blood Consumption and Trauma-Associated Severe Hemorrhage scores. Validation studies have shown that both scoring systems perform similarly. Both scores reliably identify patients that will not require an MT, while simultaneously overpredicting MT requirements. However, each scoring system has its unique advantages and disadvantages, and this review discusses how specific aspects of each scoring system can affect widespread applicability and statistical performance. In addition, we discuss the often overlooked topic of initiating MT in nontrauma patients and the specific tools physicians have to guide the MT initiation decision in this unique setting. Despite the serious complications that can arise with transfusion of large volumes of blood products, there is considerably less research pertinent to the topic of MTP termination. Societal recommendations on MTP termination emphasize applying clinical reasoning to identify patients who have bleeding source control and are adequately resuscitated. This review, however, focuses primarily on the recommendations presented by the Advanced Bleeding Care in Trauma's MTP guidelines that call for prompt termination of the algorithm-guided model of resuscitation and rapidly transitioning into a resuscitation model guided by laboratory test results. We also discuss the evidence in support of laboratory result-guided resuscitation and how recent literature on viscoelastic hemostatic assays, although limited, highlights the potential to achieve additional benefits from this method of resuscitation.

Prehospital Blood Transfusions in Non-Trauma Patients

INTRODUCTION

Despite advances in trauma care, hemorrhage continues to be the leading cause of preventable mortality in trauma. The evidence to support its use in non-trauma patients is limited. We aim to report our experience with prehospital blood product transfusion. We hypothesize that it is safe, appropriately utilized, and that our protocol, which was designed for trauma patients, is adaptable to fit the needs of non-trauma patients.

METHODS

Patients transfused with blood products, packed red blood cells (pRBCs) or plasma, in the prehospital environment between 2002 and 2014 were included. Trauma patients were compared to non-trauma patients using descriptive statistics.

RESULTS

A total of 857 patients (n = 549 trauma and n = 308 non-trauma) were transfused with pRBCs (76 %, n = 654, mean 1.6 ± 1.1 units en route), plasma (53 %, n = 455, mean 1.7 ± 0.7 unit), or both (29 %, n = 252) during ground (12 %) or air (84 %) critical care transport. Mean age was 60.8 ± 21.6 years with 60.1 % (n = 515) males. Subsequently, in-hospital blood transfusions were performed in 80 % of patients, operations in 44 %, and endoscopy in 31 %. Five percent (n = 41) of patients did not require any of these interventions. Thirty-day mortality rate was 18 %, and one patient (<0.01 %) had a transfusion reaction. The majority of patients were non-trauma (n = 549, 64 %). Of the non-trauma patients, 219 (40 %) were surgical, 193 (35 %) gastrointestinal bleeds, and 137 (25 %) medical.

CONCLUSION

Both non-trauma and trauma patients require blood products for life threatening hemorrhage and the majority required further interventions. Further research on the benefits of transfusion among non-trauma patients is warranted.

Logistical Concerns for Prehospital Blood Product Use by Air Medical Services

Over the past few decades, reports have described favorable results from transfusion of blood products in helicopter EMS (HEMS). Nevertheless, the initiation of a HEMS transfusion program requires consideration of many factors, some unique to each clinical site. This paper describes our experience developing a HEMS transfusion program in an urban non-hospital based HEMS program with a history of long transport times. When considering blood use away from the hospital, major consideration must be given to safe storage and monitoring of blood products both on the ground and while in flight. PRBCs have been shown to generally be resilient to helicopter transit and have a prolonged storage duration. Transfusion of other blood products, such as plasma, involves additional challenges but has been achieved by some HEMS sites. Flight protocols should be developed addressing when and how many blood products should be transported, potentially considering patient factors, scene factors, and the regional availability of blood products during interfacility transport. Quality assurance and documentation protocols must also be developed for blood product use in flight. In our center's experience, we have so far transfused a limited number of patients with generally good results. Patient outcomes are described as below.

Prehospital Transfusion for Gastrointestinal Bleeding

OBJECTIVE

Gastrointestinal (GI) bleeding is a common medical emergency with significant morbidity and mortality. Many patients are coagulopathic, which may perpetuate bleeding. Remote damage control resuscitation, including early correction of coagulopathy and anemia, may benefit exsanguinating patients with GI bleeding.

METHODS

We conducted a retrospective review of patients with acute GI bleeding who received packed red blood cells (pRBC) and/or plasma during transportation to our institution between 2010 and 2014. A comparison group of patients who were not transfused en route was selected, and demographics, outcomes, and response to resuscitation were compared.

RESULTS

A total of 112 patients with GI bleeding received pRBC (82%, n = 92 pRBC, mean 1.7 ± 0.9 units), plasma (62%, n = 69, mean 1.7 ± 0.8 units) or both (44%, n = 49) en-route. The comparison group comprised 49 patients transported by helicopter who were not transfused en-route. Demographics, crystalloid resuscitation, transfusion prior to transfer, rate of intervention, ICU days, length of stay, and mortality were similar between groups. Patients transfused en route had a significant increase in hemoglobin from 8.3 ± 2.2 to 8.9 ± 2.1 (P = .03) and decrease in INR from 2.0 ± 1.0 to 1.6 ± 1.4 (P = .01), whereas those not transfused en route experienced stable hemoglobin (8.7 ± 2.8 to 9.4 ± 2.5; P = .21) and INR values (1.9 ± 1.0 to 1.6 ± 1.4; P = .32). Both groups had a significant improvement in hemodynamic parameters with resuscitation.

CONCLUSION

Prehospital damage control resuscitation with pRBC and/or plasma resulted in the improvement of hemodynamic instability, coagulopathy and anemia in patients with acute GI bleeding. Almost all patients required additional inpatient interventions and/or transfusions, suggesting that pre-hospital transfusion is being utilized for appropriately selected patients.

Volumetric control of whole blood collection in austere environments

INTRODUCTION

Fresh whole blood transfusions are a powerful tool in prehospital care; however, the lack of equipment such as a scale in field situations frequently leads to collections being under- or overfilled, leading to complications for both patient and physician. This study describes two methods for simple, rapid control of collection bag volume: (1) a length of material to constrict the bag, and (2) folding/clamping the bag.

METHOD

Whole blood collection bags were allowed to fill with saline via gravity. Paracord, zip-tie, beaded cable tie, or tourniquet was placed around the bag at circumferences of 6 to 8.75 inches. A hemostat was used to clamp folds of 1 to 1.5 inches. Several units were drawn during training exercises of the 75th Ranger Regiment with volume controlled by three methods: vision/touch estimation, constriction by paracord, and clamping with hemostat.

RESULTS

Method validation in the Terumo 450-mL bag indicated that paracord, zip-tie, and beaded cable tie lengths of 6.5 inches or clamping 1.25 inches with a hemostat provided accurate filling. The volume variance was significantly lower when using the beaded cable tie. Saline filling time was approximately 2 minutes. With the Fenwal 450-mL bag, the beaded cable tie gave best results; even if incorrectly placed by one/two beads, the volume was still within limits. In training exercises, the use of the cord/clamp greatly reduced the variability; more bags were within limits.

CONCLUSIONS

Both constricting and clamping allow for speed and consistency in blood collection. The use of common cord is appealing, but knot tying induces inevitable variability; a zip/cable tie is easier. Clamping was quicker but susceptible to high variance and bag rupturing. With proper methodological training, appropriate volumes can be obtained in any environment with minimal tools.

LEVEL OF EVIDENCE

Therapeutic/care management study, level IV.

Prehospital blood transfusions in pediatric trauma and nontrauma patients: a single-center review of safety and outcomes

PURPOSE

Prehospital transfusions are a novel yet increasingly accepted intervention in the adult population as part of remote damage control resuscitation, but prehospital transfusions remain controversial in children. Our purpose was to review our pediatric prehospital transfusion experience over 12 years to describe the safety of prehospital transfusion in appropriately triaged trauma and nontrauma patients.

METHODS

Children (<18 years) transfused with packed red blood cells (pRBC) or plasma during transport to a single regional academic medical center between 2002 and 2014 were identified. Admission details, in-hospital clinical course, and outcomes were analyzed.

RESULTS

28 children were transfused during transport; median age was 8.9 ± 7 years and 15 patients were male (54%). Most patients required at least one additional unit of blood products during their hospitalization (79%), and/or required operative intervention (53%), endoscopy (7%), or died during their hospitalization (14%). Comparison of trauma patients (n = 16) and nontrauma patients (n = 12) revealed that nontrauma patients were younger, more anemic, more coagulopathy on admission, and required more ongoing transfusion in the hospital. Trauma patients were more likely to need operative intervention. No patient had a transfusion reaction.

CONCLUSION

Remote damage control prehospital transfusions of blood products were safe in this small group of appropriately triaged pediatric patients. Further studies are needed to determine if outcomes are improved and to devise a rigorous protocol for this prehospital intervention for critically ill pediatric patients.

Multicenter observational prehospital resuscitation on helicopter study

BACKGROUND

Earlier use of in-hospital plasma, platelets, and red blood cells (RBCs) has improved survival in trauma patients with severe hemorrhage. Retrospective studies have associated improved early survival with prehospital blood product transfusion (PHT). We hypothesized that PHT of plasma and/or RBCs would result in improved survival after injury in patients transported by helicopter.

METHODS

Adult trauma patients transported by helicopter from the scene to nine Level 1 trauma centers were prospectively observed from January to November 2015. Five helicopter systems had plasma and/or RBCs, whereas the other four helicopter systems used only crystalloid resuscitation. All patients meeting predetermined high-risk criteria were analyzed. Patients receiving PHT were compared with patients not receiving PHT. Our primary analysis compared mortality at 3 hours, 24 hours, and 30 days, using logistic regression to adjust for confounders and site heterogeneity to model patients who were matched on propensity scores.

RESULTS

Twenty-five thousand one hundred eighteen trauma patients were admitted, 2,341 (9%) were transported by helicopter, of which 1,058 (45%) met the highest-risk criteria. Five hundred eighty-five of 1,058 patients were flown on helicopters carrying blood products. In the systems with blood available, prehospital median systolic blood pressure (125 vs 128) and Glasgow Coma Scale (7 vs 14) was significantly lower, whereas median Injury Severity Score was significantly higher (21 vs 14). Unadjusted mortality was significantly higher in the systems with blood products available, at 3 hours (8.4% vs 3.6%), 24 hours (12.6% vs 8.9%), and 30 days (19.3% vs 13.3%). Twenty-four percent of eligible patients received a PHT. A median of 1 unit of RBCs and plasma were transfused prehospital. Of patients receiving PHT, 24% received only plasma, 7% received only RBCs, and 69% received both. In the propensity score matching analysis (n = 109), PHT was not significantly associated with mortality at any time point, although only 10% of the high-risk sample were able to be matched.

CONCLUSION

Because of the unexpected imbalance in systolic blood pressure, Glasgow Coma Scale, and Injury Severity Score between systems with and without blood products on helicopters, matching was limited, and the results of this study are inconclusive. With few units transfused to each patient and small outcome differences between groups, it is likely large, multicenter, randomized studies will be required to detect survival differences in this important population.

LEVEL OF EVIDENCE

Level II.

The state of the science of whole blood: lessons learned at Mayo Clinic

AABB Standards specify that ABO group-specific whole blood is the only acceptable choice for whole blood transfusions. Although universal donor group O stored whole blood (SWB) was used extensively by the military during the wars of the mid-twentieth century, its use has fallen out of favor and has never been used to great extent in the civilian trauma population. Interest in the use of whole blood has been renewed, particularly in light of its potential value in far-forward military and other austere environments. Evidence of preserved platelet function in SWB has heightened enthusiasm for a "one stop shop" resuscitation product providing volume, oxygen carrying capacity, and hemostatic effects. Experience with universal donor group O SWB is required to ascertain whether its use will be an advance in trauma care. Described here is the process of establishing a universal donor group O SWB at a civilian trauma center in the United States.

Tactical Combat Casualty Care and Wilderness Medicine: Advancing Trauma Care in Austere Environments

Tactical Combat Casualty Care (TCCC) is a set of evidence-based, best-practice prehospital trauma care guidelines customized for use on the battlefield. Military units that have trained all of their unit members in TCCC have now documented the lowest incidence of preventable deaths in the history of modern warfare and TCCC is now the standard for battlefield trauma care in the US Military. TCCC and wilderness medicine share the goal of optimizing care for patients with trauma in austere environments that impose significant challenges in both equipment and evacuation capability. This article reviews the current battlefield trauma care recommendations in TCCC and discusses their applicability to the wilderness setting.

Forward medevac during Serval and Barkhane operations in Sahel: A registry study

INTRODUCTION

The French army has been deployed in Mali since January 2013 with the Serval Operation and since July 2014 in the Sahel-Saharan Strip (SSS) with the Barkhane Operation where the distances (up to 1100km) can be very long. French Military Medical Service deploys an inclusive chain from the point of injury (POI) to hospital in France. A patient evacuation coordination cell (PECC) has been deployed since February 2013 to organise forward medical evacuation (MEDEVAC) in the area between the POI and three forward surgical units. The purpose of this work was to study the medical evacuation length and duration between the call for Medevac location accidents and forward surgical units (role 2) throughout the five million square kilometers French joint operation area.

MATERIALS AND METHODS

Our retrospective study concerns the French patients evacuated by MEDEVAC from February 2013 to July 2016. The PECC register was analysed for patients' characteristics, NATO categorisation of gravity (Alpha, Bravo or Charlie who must be respectively at hospital facility within 90min, 4h or 24h), medical motive for MEDEVAC and the time line of each MEDEVAC (from operational commander request to entrance in role 2).

RESULTS

A total of 1273 French military were evacuated from February to 2013 to July 2016; 533 forward MEDEVAC were analysed. 12,4% were Alpha, 28,1% Bravo, 59,5% Charlie. War-related injury represented 18,2% of MEDEVAC. The median time for Alpha category MEDEVAC patients was 145min [100-251], for Bravo category patients 205min [125-273] and 310min [156-669] for Charlie. The median distance from the point of injury to role 2 was 126km [90-285] for Alpha patients, 290km [120-455] km for Bravo and 290km [105-455] for Charlie.

CONCLUSIONS

Patient evacuation in such a large area is a logistic and human challenge. Despite this, Bravo and Charlie patients were evacuated in NATO recommended time frame. However, due to distance, Alpha patients time frame was longer than this recommended by NATO organisation. That's where French doctrine with forward medical teams embedded in the platoons is relevant to mitigate this distance and time frame challenge.

Prehospital use of blood and plasma in pediatric trauma patients

OBJECTIVE

Our rural trauma center uses packed red blood cells (PRBCs) and plasma onboard our helicopter to offset the delay of transport. We summarize our initial experience with prehospital blood use in pediatric trauma patients.

METHODS

Our air ambulance service began carrying PRBCs in 1987 and plasma in 2009. We performed a 9-year retrospective review including patients (< 18 years) who received blood during helicopter transports. Only patients transported to our level 1 trauma center were included to ensure complete follow-up.

RESULTS

Sixteen patients (6 females) were identified with a mean age of 13 years. The mean transport time was 30 minutes with 75% transferred in from a referring center. Injuries were blunt in 9 patients and penetrating in 2 patients. The mean Injury Severity Score was 30. Fifteen patients received an average of 1.5 units of PRBCs during flight. Indications for PRBCs were severe anemia (6), known blood loss (5), and nonresponder to intravenous fluids (4). Average hemoglobin improved from 9.4 to 11.4 mg/dL at our center. Base deficit improved from -7 to -5.7 at arrival. Five patients received a mean of 1.4 units of plasma. The arrival international normalized ratio was 1.4. The average length of stay was 9.3 days. Four patients died. Trauma Related Injury Severity Score showed 3 patients were unexpected survivors (0.24, 0.24, and 0.38).

CONCLUSION

Prehospital use of blood in injured children is rare. However, when indicated, this initial review of our protocol showed increased hemoglobin, decreased acidosis, and unexpected survivors with our program. Because of the rarity of prehospital blood use in children, administration triggers require continued review and refinement.

2016: emergency medical services annotated literature in review

In the daily practice of emergency medicine, physicians constantly interact with components of emergency medical services systems. The provision of high-quality care in the prehospital setting requires emergency physicians to remain abreast of recent literature that may inform the care of patients prior to their arrival at the emergency department. This literature review will examine some recent trends in the prehospital literature. In addition, the review will highlight important areas of clinical practice which represent some of the many intersections between emergency medicine and emergency medical services such as cardiac arrest and airway management.

Advances in damage control resuscitation and surgery: implications on the organization of future military field forces

Medical support to deployed field forces is increasingly becoming a shared responsibility among allied nations. National military medical planners face several key challenges, including fiscal restraints, raised expectations of standards of care in the field and a shortage of appropriately trained specialists. Even so, medical services are now in high demand, and the availability of medical support may become the limiting factor that determines how and where combat units can deploy. The influence of medical factors on operational decisions is therefore leading to an increasing requirement for multinational medical solutions. Nations must agree on the common standards that govern the care of the wounded. These standards will always need to take into account increased public expectations regarding the quality of care. The purpose of this article is to both review North Atlantic Treaty Organization (NATO) policies that govern multinational medical missions and to discuss how recent scientific advances in prehospital battlefield care, damage control resuscitation and damage control surgery may inform how countries within NATO choose to organize and deploy their field forces in the future.

Prehospital use of plasma in traumatic hemorrhage (The PUPTH Trial): study protocol for a randomised controlled trial

Background

Severe traumatic injury and haemorrhagic shock are frequently associated with disruptions of coagulation function (such as trauma-induced coagulopathy TIC) and activation of inflammatory cascades. These pathologies may be exacerbated by current standard of care resuscitation protocols. Observational studies suggest early administration of plasma to severely-injured haemorrhaging patients may correct TIC, minimise inflammation, and improve survival. The proposed randomised clinical trial will evaluate the clinical effectiveness of pre-hospital plasma administration compared with standard- of-care crystalloid resuscitation in severely-injured patients with major traumatic haemorrhage.

Methods/design

This is a prospective, randomized, open-label, non-blinded trial to determine the effect of pre-hospital administration of thawed plasma (TP) on mortality, morbidity, transfusion requirements, coagulation, and inflammatory response in severely-injured bleeding trauma patients. Two hundred and ten eligible adult trauma patients will be randomised to receive either two units of plasma, to be administered in-field, vs standard of care normal saline (NS). Main analyses will compare subjects allocated to TP to those allocated to NS, on an intention-to-treat basis. Primary outcome measure is all-cause 30-day mortality. Secondary outcome measures include coagulation and lipidomic/pro-inflammatory marker responses, volume of resuscitation fluids (crystalloid, colloid) and blood products administered, and major hospital outcomes (e.g. incidence of MSOF, length of ICU stay, length of hospital stay).

Discussion

This study is part of a US Department of Defense (DoD)-funded multi-institutional investigation, conducted independently of, but in parallel with, the University of Pittsburgh and University of Denver. Demonstration of significant reductions in mortality and coagulopathic/inflammatory-related morbidities as a result of pre-hospital plasma administration would be of considerable clinical importance for the management of haemorrhagic shock in both civilian and military populations.

Trial registration

ClinicalTrials.gov: NCT02303964 on 28 November 2014

Pretrauma center red blood cell transfusion is associated with reduced mortality and coagulopathy in severely injured patients with blunt trauma

OBJECTIVE

To evaluate the association of pretrauma center (PTC) red blood cell (RBC) transfusion with outcomes in severely injured patients.

BACKGROUND

Hemorrhage remains a major driver of mortality. Little evidence exists supporting PTC interventions to mitigate this.

METHODS

Blunt injured patients in shock arriving at a trauma center within 2 hours of injury were included from the Glue Grant database. Subjects were dichotomized by PTC RBC transfusion. Outcomes included 24-hour mortality, 30-day mortality, and trauma-induced coagulopathy [(TIC), admission international normalized ratio >1.5]. Cox regression and logistic regression determined the association of PTC RBC transfusion with outcomes. To address baseline differences, propensity score matching was used.

RESULTS

Of 1415 subjects, 50 received PTC RBC transfusion. Demographics and injury severity score were similar. The PTC RBC group received 1.3 units of RBCs (median), and 52% were scene transports. PTC RBC transfusion was associated with a 95% reduction in odds of 24-hour mortality [odds ratio (OR) = 0.05; 95% confidence interval (CI), 0.01-0.48; P < 0.01], 64% reduction in the risk of 30-day mortality [hazard ratio = 0.36; 95% CI, 0.15-0.83; P = 0.02], and 88% reduction in odds of TIC (OR = 0.12; 95% CI, 0.02-0.79; P = 0.03). The matched cohort included 113 subjects (31% PTC RBC group). Baseline characteristics were similar. PTC RBC transfusion was associated with a 98% reduction in odds of 24-hour mortality (OR = 0.02; 95% CI, 0.01-0.69; P = 0.04), 88% reduction in the risk of 30-day mortality (hazard ratio = 0.12; 95% CI, 0.03-0.61; P = 0.01), and 99% reduction in odds of TIC (OR = 0.01; 95% CI, 0.01-0.95; P = 0.05).

CONCLUSIONS

PTC RBC administration was associated with a lower risk of 24-hour mortality, 30-day mortality, and TIC in severely injured patients with blunt trauma, warranting further prospective study.

How we provide thawed plasma for trauma patients

Almost 50% of trauma-related fatalities within the first 24 hours of injury are related to hemorrhage. Improved survival in severely injured patients has been demonstrated when massive transfusion protocols are rapidly invoked as part of a therapeutic approach known as damage control resuscitation (DCR). DCR incorporates the early use of plasma to prevent or correct trauma-induced coagulopathy. DCR often requires the transfusion of plasma before determination of the recipient's ABO group. Historically, group AB plasma has been considered the "universal donor" plasma product. At our facility, the number of AB plasma products produced on an annual basis was found to be inadequate to support the trauma service's DCR program. A joint decision was made by the transfusion medicine and trauma services to provide group A thawed plasma (TP) for in-hospital and prehospital DCR protocols. A description of the implementation of group A TP into the DCR program is provided as well as outcome data pertaining to the use of TP in trauma patients.

Pre-hospital intra-osseous freeze dried plasma transfusion: a case report

Background

Hemorrhage and coagulopathy are among the leading causes of death in combat and are considered the leading causes of preventable deaths. Plasma, in the form of Fresh Frozen Plasma (FFP) is considered a key component in the Damage Control Resuscitation performed within hospitals. Freeze-Dried Plasma (FDP) can be stored at room temperature and therefore is potentially useful in pre-hospital conditions. Our case report join to few cases where FDP was administered at the point of injury. It is also unique as it describes an intra- osseous administration given to pediatric patient.

Case report

M.S. otherwise healthy 13 year old girl was injured due to gunshots and grenade blast. On the first triage by the IDF medical teams she suffered from: Severe hemorrhagic shock, (Blood pressure could not be measured, Heart rate 163), superficial wounds to her face, (forehead and Rt. Eye), gunshot wounds with active bleeding from her Lt. Arm and her RT. Knee (Mangled Extremity Severity Score (MESS) 8) and open fractures of left elbow and right thigh. A peripheral intravenous catheter was established and 1 g tranexamic acid in 500 ml of Hartman fluid were administered. Due to difficulties in establishing a functioning intra-venous line, an intra-osseous catheter was established and one unit of FDP (250 ml) was given in the field. She was transferred by a military medical team to a regional civilian hospital for further treatment. Upon arrival to the hospital her blood pressure and heart rate were significantly improved. After three weeks of hospitalization M.S. was discharged and she was returned to her homeland.

Conclusion

We have described the successful use of FDP for pre hospital resuscitation of a 13 year old girl suffering from severe hemorrhagic shock as a result of gunshots and grenade blast. This case report demonstrates that intra-osseous FDP administration for as part pre hospital resuscitation of children has a favorable outcome.

Taking the Blood Bank to the Field: The Design and Rationale of the Prehospital Air Medical Plasma (PAMPer) Trial

Hemorrhage and trauma induced coagulopathy remain major drivers of early preventable mortality in military and civilian trauma. Interest in the use of prehospital plasma in hemorrhaging patients as a primary resuscitation agent has grown recently. Trauma center-based damage control resuscitation using early and aggressive plasma transfusion has consistently demonstrated improved outcomes in hemorrhaging patients. Additionally, plasma has been shown to have several favorable immunomodulatory effects. Preliminary evidence with prehospital plasma transfusion has demonstrated feasibility and improved short-term outcomes. Applying state-of-the-art resuscitation strategies to the civilian prehospital arena is compelling. We describe here the rationale, design, and challenges of the Prehospital Air Medical Plasma (PAMPer) trial. The primary objective is to determine the effect of prehospital plasma transfusion during air medical transport on 30-day mortality in patients at risk for traumatic hemorrhage. This study is a multicenter cluster randomized clinical trial. The trial will enroll trauma patients with profound hypotension (SBP ≤ 70 mmHg) or hypotension (SBP 71-90 mmHg) and tachycardia (HR ≥ 108 bpm) from six level I trauma center air medical transport programs. The trial will also explore the effects of prehospital plasma transfusion on the coagulation and inflammatory response following injury. The trial will be conducted under exception for informed consent for emergency research with an investigational new drug approval from the U.S. Food and Drug Administration utilizing a multipronged community consultation process. It is one of three ongoing Department of Defense-funded trials aimed at expanding our understanding of the optimal therapeutic approaches to coagulopathy in the hemorrhaging trauma patient.

Pre-trauma center red blood cell transfusion is associated with improved early outcomes in air medical trauma patients

BACKGROUND

Hemorrhage is the leading cause of survivable death in trauma and resuscitation strategies including early RBC transfusion have reduced this. Pre-trauma center (PTC) RBC transfusion is growing and preliminary evidence suggests improved outcomes. The study objective was to evaluate the association of PTC RBC transfusion with outcomes in air medical trauma patients.

STUDY DESIGN

We conducted a retrospective cohort study of trauma patients transported by helicopter to a Level I trauma center from 2007 to 2012. Patients receiving PTC RBC transfusion were matched to control patients (receiving no PTC RBC transfusion during transport) in a 1:2 ratio using a propensity score based on prehospital variables. Conditional logistic regression and mixed-effects linear regression were used to determine the association of PTC RBC transfusion with outcomes. Subgroup analysis was performed for scene transport patients.

RESULTS

Two-hundred and forty treatment patients were matched to 480 control patients receiving no PTC RBC transfusion. Pre-trauma center RBC transfusion was associated with increased odds of 24-hour survival (adjusted odds ratio [AOR] = 4.92; 95% CI, 1.51-16.04; p = 0.01), lower odds of shock (AOR = 0.28; 95% CI, 0.09-0.85; p = 0.03), and lower 24-hour RBC requirement (Coefficient -3.6 RBC units; 95% CI, -7.0 to -0.2; p = 0.04). Among matched scene patients, PTC RBC was also associated with increased odds of 24-hour survival (AOR = 6.31; 95% CI, 1.88-21.14; p < 0.01), lower odds of shock (AOR = 0.24; 95% CI, 0.07-0.80; p = 0.02), and lower 24-hour RBC requirement (Coefficient -4.5 RBC units; 95% CI, -8.3 to -0.7; p = 0.02).

CONCLUSIONS

Pre-trauma center RBC was associated with an increased probability of 24-hour survival, decreased risk of shock, and lower 24-hour RBC requirement. Pre-trauma center RBC appears beneficial in severely injured air medical trauma patients and prospective study is warranted as PTC RBC transfusion becomes more readily available.

Implementation and execution of civilian remote damage control resuscitation programs

Remote damage control resuscitation is a recently defined term used to describe techniques and strategies to provide hemostatic resuscitation to injured patients in the prehospital setting. In the civilian setting, unlike the typical military setting, patients who require treatment for hemorrhage come in all ages with all types of comorbidities and have bleeding that may be non-trauma related. Thus, in the austere setting, addressing the needs of the patient is no less challenging than in the military environment, albeit the caregivers are typically not putting their lives at risk to provide such care. Two organizations have pioneered remote damage control resuscitation in the civilian environment: Mayo Clinic and Royal Caribbean Cruises Ltd. The limitations in rural Minnesota and shipboard are daunting. Patients who have hemorrhage requiring transfusion are often hundreds of miles from hospitals able to provide damage control resuscitation. This article details the development and implementation of novel programs specifically designed to address the varied needs of patients in such circumstances. The Mayo Clinic program essentially takes a standard-of-care treatment algorithm, by which the patient would be treated in the emergency department or trauma bay, and projects that forward into the rural environment with specially trained prehospital personnel and special resources. Royal Caribbean Cruises Ltd has adapted a traditional military field practice of transfusing warm fresh whole blood, adding significant safety measures not yet reported on the battlefield (see within this Supplement the article entitled "Emergency Whole Blood Use in the Field: A Simplified Protocol for Collection and Transfusion"). The details of development, implementation, and preliminary results of these two civilian programs are described herein.

Protocol for a systematic review of the clinical effectiveness of pre-hospital blood components compared to other resuscitative fluids in patients with major traumatic haemorrhage

BACKGROUND

There is growing interest in the use of blood components for pre-hospital resuscitation of patients with major traumatic haemorrhage. It has been speculated that early resuscitation with blood components may have benefits in terms of treating trauma-induced coagulopathy, which in turn may influence survival. The proposed systematic review will evaluate the evidence on the clinical effectiveness of pre-hospital blood components (red blood cells and/or plasma or whole blood), in both civilian and military settings, compared with other resuscitation strategies in patients with major traumatic haemorrhage.

METHODS/DESIGN

Standard systematic review methods aimed at minimising bias will be employed for study identification, selection and data extraction. General medical and specialist databases will be searched; the search strategy will combine terms for the population, intervention and setting. Studies will be selected for review if the population includes adult patients with major traumatic haemorrhage who receive blood components in a pre-hospital setting (civilian or military). Systematic reviews, randomised and non-randomised controlled trials and controlled observational studies will be included. Uncontrolled studies will be considered depending on the volume of controlled evidence. Quality assessment will be tailored to different study designs. Both patient related and surrogate outcomes will be considered. Synthesis is likely to be primarily narrative, but meta-analyses and subgroup analyses will be undertaken where clinical and methodological homogeneity exists.

DISCUSSION

Given the increasing use by emergency services of blood components for pre-hospital resuscitation, this is a timely systematic review, which will attempt to clarify the evidence base for this practice. As far as the authors are aware, the proposed systematic review will be the first to address this topic.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42014013794.

Exploring ethical conflicts in emergency trauma research: the COMBAT (Control of Major Bleeding after Trauma) study experience

BACKGROUND

Up to 25% of severely injured patients develop trauma-induced coagulopathy. To study interventions for this vulnerable population for whom consent cannot be obtained easily, the Food and Drug Administration issued regulations for emergency research with an exception from informed consent (ER-EIC). We describe the community consultation and public disclosure (CC/PD) process in preparation for an ER-EIC study, namely the Control Of Major Bleeding After Trauma (COMBAT) study.

METHODS

The CC/PD was guided by the four bioethical principles. We used a multimedia approach, including one-way communications (newspaper ads, brochures, television, radio, and web) and two-way communications (interactive in-person presentations at community meetings, printed and online feedback forms) to reach the trials catchment area (Denver County's population: 643,000 and the Denver larger metro area where commuters reside: 2.9 million). Particular attention was given to special-interests groups (eg, Jehovah Witnesses, homeless) and to Spanish-speaking communities (brochures and presentations in Spanish). Opt-out materials were available during on-site presentations or via the COMBAT study website.

RESULTS

A total of 227 community organizations were contacted. Brochures were distributed to 11 medical clinics and 3 homeless shelters. The multimedia campaign had the potential to reach an estimated audience of 1.5 million individuals in large metro Denver area, the majority via one-way communication and 1900 in two-way communications. This resource intensive process cost more than $84,000.

CONCLUSION

The CC/PD process is resource-intensive, costly, and complex. Although the multimedia CC/PD reached a large audience, the effectiveness of this process remains elusive. The templates can be helpful to similar ER-EIC studies.

Modern resuscitation of hemorrhagic shock: what is on the horizon?

PURPOSE

Mortality rates among the severely injured remain high. The successful treatment of hemorrhagic shock relies on expeditious control of bleeding through surgical ligation, packing, or endovascular techniques. An important secondary concern in hemorrhaging patients is how to respond to the lost blood volume. A single method that is able to adequately address all needs of the exsanguinating patient has not yet been agreed upon, despite a large growth of knowledge regarding the causative factors of traumatic shock.

METHODS

A review of relevent literature was performed.

CONCLUSIONS

Many different trials are currently underway to discriminate ways to improve outcomes in the severely injured and bleeding patient.  This paper will review: (1) recent advances in our understanding of the effects hemorrhagic shock has on the coagulation cascade and vascular endothelium, (2) recent research findings that have changed resuscitation, and (3) resuscitation strategies that are not widely used but under active investigation.

Prehospital Transfusion of Plasma and Red Blood Cells in Trauma Patients

Abstract Objective. Earlier use of plasma and red blood cells (RBCs) has been associated with improved survival in trauma patients with substantial hemorrhage. We hypothesized that prehospital transfusion (PHT) of thawed plasma and/or RBCs would result in improved patient coagulation status on admission and survival. Methods. Adult trauma patient records were reviewed for patient demographics, shock, coagulopathy, outcomes, and blood product utilization from September 2011 to April 2013. Patients arrived by either ground or two different helicopter companies. All patients transfused with blood products (either pre- or in-hospital) were included in the study. One helicopter system (LifeFlight, LF) had thawed plasma and RBCs while the other air (OA) and ground transport systems used only crystalloid resuscitation. Patients receiving PHT were compared with all other patients meeting entry criteria to the study cohort. All comparisons were adjusted in multilevel regression models. Results. A total of 8,536 adult trauma patients were admitted during the 20-month study period, of which 1,677 met inclusion criteria. They represented the most severely injured patients (ISS = 24 and mortality = 26%). There were 792 patients transported by ground, 716 by LF, and 169 on OA. Of the LF patients, 137 (19%) received prehospital transfusion. There were 942 units (244 RBCs and 698 plasma) placed on LF helicopters, with 1.9% wastage. PHT was associated with improved acid-base status on hospital admission, decreased use of blood products over 24 hours, a reduction in the risk of death in the sickest patients over the first 6 hours after admission, and negligible blood products wastage. In this small single-center pilot study, there were no differences in 24-hour (odds ratio 0.57, p = 0.117) or 30-day mortality (odds ratio 0.71, p = 0.441) between LF and OA. Conclusions. Prehospital plasma and RBC transfusion was associated with improved early outcomes, negligible blood products wastage, but not an overall survival advantage. Similar to the data published from the ongoing war, improved early outcomes are associated with placing blood products prehospital, allowing earlier infusion of life-saving products to critically injured patients.

Resuscitate early with plasma and platelets or balance blood products gradually: findings from the PROMMTT study

BACKGROUND

The trauma transfusion literature has yet to resolve which is more important for hemorrhaging patients, transfusing plasma and platelets along with red blood cells (RBCs) early in resuscitation or gradually balancing blood product ratios. In a previous report of PROMMTT results, we found (1) plasma and platelet:RBC ratios increased gradually during the 6 hours following admission, and (2) patients achieving ratios more than 1:2 (relative to ratios <1:2) had significantly decreased 6-hour to 24-hour mortality adjusting for baseline and time-varying covariates. To differentiate the association of in-hospital mortality with early plasma or platelet transfusion from that with delayed but gradually balanced ratios, we developed a separate analytic approach.

METHODS

Using PROMMTT data and multilevel logistic regression to adjust for center effects, we related in-hospital mortality to the early receipt of plasma or platelets within the first three to six transfusion units (including RBCs) and 2.5 hours of admission. We adjusted for the same covariates as in our previous report: Injury Severity Score (ISS), age, time and total number of blood product transfusions upon entry to the analysis cohort, and bleeding from the head, chest, or limb.

RESULTS

Of 1,245 PROMMTT patients, 619 were eligible for this analysis. Early plasma was associated with decreased 24-hour and 30-day mortality (adjusted odds ratios of 0.47 [p = 0.009] and 0.44 [p = 0.002], respectively). Too few patients (24) received platelets early for meaningful assessment. In the subgroup of 222 patients receiving no early plasma but continuing transfusions beyond Hour 2.5, achieving gradually balanced plasma and platelet:RBC ratios of 1:2 or greater by Hour 4 was not associated with 30-day mortality (adjusted odds ratios of 0.9 and 1.1, respectively). There were no significant center effects.

CONCLUSION

Plasma transfusion early in resuscitation had a protective association with mortality, whereas delayed but gradually balanced transfusion ratios did not. Further research will require considerably larger numbers of patients receiving platelets early.

The development and feasibility of a remote damage control resuscitation prehospital plasma transfusion protocol for warfarin reversal for patients with traumatic brain injury

BACKGROUND

The rapid reversal of warfarin in the setting of traumatic brain injury (TBI) has been associated with improved outcomes. Until now, remote reversal of hypocoagulable states has not been possible in the prehospital environment. This manuscript describes the development and analysis of a prehospital plasma transfusion protocol to reverse warfarin at the earliest possible moment after TBI.

STUDY DESIGN AND METHODS

A retrospective review of all TBI patients receiving plasma transfusion(s) in the prehospital environment for warfarin reversal between February 2009 and September 2010 was conducted. Thawed plasma was carried on every air ambulance flight centered at the main campus.

RESULTS

A total of 2836 flights carried over 2500 units of thawed plasma throughout the study period. During this time, 16 patients received prehospital plasma resuscitation, five of who were on warfarin with a concurrent TBI. The median Injury Severity Score was 17 (8.5-27.5) with a median Glasgow Coma Score of 13 (8-15) and a mortality rate of 40%. A median of 2 (1.5-2.0) units of thawed plasma and 0 (0-0) units of RBCs were transfused en route. The pretransfusion point-of-care international normalized ratio improved from 3.1 (2.3-4.0) to 1.9 (1.3-3.6) upon trauma center admission (serum sample). One hundred percent of the transported, but unused, thawed plasma underwent subsequent transfusion prior to expiration.

CONCLUSIONS

Remote prehospital plasma transfusions effectively reverse anticoagulation secondary to warfarin administration in TBI patients. It is feasible to transfuse thawed plasma in the prehospital setting via remote damage control techniques without increasing waste. Prospective studies are needed to determine if this practice can improve outcomes in this population.

Remote damage control resuscitation and the Solstrand Conference: defining the need, the language, and a way forward

Damage control resuscitation (DCR) is emerging as a standard practice in civilian and military trauma care. Primary objectives include resolution of immediate life threats followed by optimization of physiological status in the perioperative period. To accomplish this, DCR employs a unique hypotensive-hemostatic resuscitation strategy that avoids traditional crystalloid intravenous fluids in favor of early blood component use in ratios mimicking whole blood. The presence of uncontrolled major hemorrhage (UMH) coupled with a delay in access to hemostatic surgical intervention remains a primary contributor to preventable death in both combat and in many domestic settings, including rural areas and disaster sites. As a result, civilian and military emergency care leaders throughout the world have sought a means to project DCR principles forward of the traditional trauma resuscitation bay, into such remote environments as disaster scenes, rural health facilities, and the contemporary battlefield. After reflecting on experiences from past conflicts, defining current capability gaps, and examining available and potential solutions, a strategy for "remote damage control resuscitation" (RDCR) has been proposed. In order for RDCR to progress from concept to clinical strategy, it will be necessary to define existing gaps in knowledge and clinical capability; develop a lexicon so that investigators and operators may understand each other; establish coherent research and development agendas; and execute comprehensive investigations designed to predict, diagnose, and mitigate the consequences of hemorrhagic shock and acute traumatic coagulopathy before they become irreversible. This article seeks to introduce the concept of RDCR; to reinforce the importance of identifying and optimally managing UMH and the resulting shock state as part of a comprehensive approach to out-of-hospital stabilization and en route care; and to propose investigational strategies to enable the development and broad implementation of RDCR principles.