Prehospital Blood Product and Crystalloid Resuscitation in the Severely Injured Patient: A Secondary Analysis of the Prehospital Air Medical Plasma Trial

Aeromedical Transport for Critically Ill Patients

Aeromedical transport (AMT) is an integral part of healthcare systems worldwide. In this article, the personnel and equipment required, associated safety considerations, and evidence supporting the use of AMT is reviewed, with an emphasis on helicopter emergency medical services (HEMS). Indications for HEMS as guideded by the Air Medical Prehospital Triage Score are presented. Lastly, physiologic considerations, which are important to both AMT crews and receiving clinicians, are reviewed.

Digital twin mathematical models suggest individualized hemorrhagic shock resuscitation strategies

BACKGROUND

Optimizing resuscitation to reduce inflammation and organ dysfunction following human trauma-associated hemorrhagic shock is a major clinical hurdle. This is limited by the short duration of pre-clinical studies and the sparsity of early data in the clinical setting.

METHODS

We sought to bridge this gap by linking preclinical data in a porcine model with clinical data from patients from the Prospective, Observational, Multicenter, Major Trauma Transfusion (PROMMTT) study via a three-compartment ordinary differential equation model of inflammation and coagulation.

RESULTS

The mathematical model accurately predicts physiologic, inflammatory, and laboratory measures in both the porcine model and patients, as well as the outcome and time of death in the PROMMTT cohort. Model simulation suggests that resuscitation with plasma and red blood cells outperformed resuscitation with crystalloid or plasma alone, and that earlier plasma resuscitation reduced injury severity and increased survival time.

CONCLUSIONS

This workflow may serve as a translational bridge from pre-clinical to clinical studies in trauma-associated hemorrhagic shock and other complex disease settings.

Factors affecting physicians' decision to start prehospital blood product transfusion in blunt trauma patients: A cohort study of Helsinki Trauma Registry

BACKGROUND

Prehospital blood transfusions are increasing as a treatment for bleeding trauma patients at risk for exsanguination. Triggers for starting transfusion in the field are less studied. We analyzed the factors affecting the decision of physicians to start prehospital blood product transfusion (PHBT) in blunt adult trauma patients.

STUDY DESIGN AND METHODS

Data of all adult blunt trauma patients from the Helsinki Trauma Registry between March 2016 and July 2021 were retrospectively analyzed. Univariate analysis for the identification of predictive factors and multivariate regression analysis for their importance as predictive factors for the initiation of PHBT were applied.

RESULTS

There were 1652 patients registered in the database. A total of 556 of them were treated by a physician-level prehospital emergency care unit, of which by transfusion-capable unit in 394 patients. PHBT (red blood cells and/or plasma) was started in 19.8% of the patients. We identified three statistically highly important clinical triggers for starting PHBT: high crystalloid volume need, shock index ≥0.9, and need for prehospital pleural decompression.

DISCUSSION

PHBT in blunt adult trauma patients is initiated in ~20% of the patients in Southern Finland. High crystalloid volume need, shock index ≥0.9 and prehospital pleural decompression are associated with the initiation of PHBT, probably reflecting patients at high risk for bleeding.

Low titer group O whole blood and risk of RhD alloimmunization: Rationale for use in Finland

BACKGROUND

Prehospital low-titer group O whole blood (LTOWB) used for patients with life-threatening hemorrhage is often RhD positive. The most important complication following RhD alloimmunization is hemolytic disease of the fetus and newborn (HDFN). Preceding clinical use of RhD positive LTOWB, we estimated the risk of HDFN due to LTOWB prehospital transfusion in the Finnish population.

STUDY DESIGN AND METHODS

We collected data on prehospital transfusions in Tampere and Helsinki University Hospital areas. Using the mean of reported alloimmunization rates in trauma studies (24%) and a higher reported rate representing trauma patients of 13-50 years old (42.7%), we estimated the risk of HDFN and extrapolated it to the whole of Finland.

RESULTS

We estimated that in Finland, with the current prehospital transfusion rate we would see 1-3 cases of severe HDFN due to prehospital LTOWB transfusions every 10 years, and fetal death due to HDFN caused by LTOWB transfusion less than once in 100 years.

DISCUSSION

The estimated risk of serious HDFN due to prehospital LTOWB transfusion in the Finnish population is similar to previous estimates. As Finland routinely screens expectant mothers for red blood cell antibodies and as the contemporary treatment of HDFN is very effective, we support the prehospital use of RhD positive LTOWB in all patient groups.

A Guide to the Use of Vasopressors and Inotropes for Patients in Shock

Shock is a life-threatening circulatory failure that results in inadequate tissue perfusion and oxygenation. Vasopressors and inotropes are vasoactive medications that are vital in increasing systemic vascular resistance and cardiac contractility, respectively, in patients presenting with shock. To be well versed in using these agents is an important skill to have in the critical care setting where patients can frequently exhibit symptoms of shock. In this review, we will discuss the pathophysiological mechanisms of shock and evaluate the current evidence behind the management of shock with an emphasis on vasopressors and inotropes.

Prehospital Trauma Care

Prehospital trauma evaluation begins with the primary assessment of airway, breathing, circulation, disability, and exposure. This is closely followed by vital signs and a secondary assessment. Key prehospital interventions include management and resuscitation according to the aforementioned principles with a focus on major hemorrhage control, airway compromise, and invasive management of tension pneumothorax. Determining the appropriate time and method for transportation (eg, ground ambulance, helicopter, police, private vehicle) to the hospital or when to terminate resuscitation are also important decisions to be made by emergency medical services clinicians.

American Association for the Surgery of Trauma/American College of Surgeons Committee on Trauma: Clinical protocol for damage-control resuscitation for the adult trauma patient

ABSTRACT

Damage-control resuscitation in the care of critically injured trauma patients aims to limit blood loss and prevent and treat coagulopathy by combining early definitive hemorrhage control, hypotensive resuscitation, and early and balanced use of blood products (hemostatic resuscitation) and the use of other hemostatic agents. This clinical protocol has been developed to provide evidence-based recommendations for optimal damage-control resuscitation in the care of trauma patients with hemorrhage.

Prehospital Blood Transfusion in Helicopter Emergency Medical Services: An Italian Survey

OBJECTIVE

Hemorrhage remains the most common cause of preventable death after trauma. Prehospital blood product (PHBP) administration may improve outcomes. No data are available about PHBP use in Italian helicopter emergency medical services (HEMS). The primary aim of this survey was to establish the degree of PHBP used throughout Italy. The secondary aims were to evaluate the main indications for their use, the opinions about PHBPs, and users' experience.

METHODS

The study group performed a telephone/e-mail survey of all 56 Italian HEMS bases. The questions concerned whether PHBPs were used in their HEMS bases, the frequency of transfusions, the PHBP used, and the perceived benefits.

RESULTS

Four of 56 HEMS bases use PHBPs. Overall, 7% have prehospital access to packed red cells and only 1 to fresh plasma. In addition to blood product administration, 4 of 4 use tranexamic acid, and 3 of 4 also use fibrinogen. Seventy-five percent use PHBPs once a month and 25% once a week. The users' experience was that PHBPs are beneficial and lifesaving.

CONCLUSION

Only 4 of 56 HEMS in Italy use PHBPs. There is an absolute consensus among providers on the benefit of PHBPs despite the lack of evidence on PHBP use.

Temporal changes in the prehospital management of trauma patients: 2014-2021

INTRODUCTION

Aggressive prehospital interventions (PHI) in trauma may not improve outcomes compared to prioritizing rapid transport. The aim of this study was to quantify temporal changes in the frequency of PHI performed by EMS.

METHODS

Retrospective chart review of adult patients transported by EMS to our trauma center from January 1, 2014 to 12/31/2021. PHI were recorded and annual changes in their frequency were assessed via year-by-year trend analysis and multivariate regression.

RESULTS

Between the first and last year of the study period, the frequency of thoracostomy (6% vs. 9%, p ​= ​0.001), TXA administration (0.3% vs. 33%, p ​< ​0.001), and whole blood administration (0% vs. 20%, p ​< ​0.001) increased. Advanced airway procedures (21% vs. 12%, p ​< ​0.001) and IV fluid administration (57% vs. 36%, p ​< ​0.001) decreased. ED mortality decreased from 8% to 5% (p ​= ​0.001) over the study period. On multivariate regression, no PHI were independently associated with increased or decreased ED mortality.

CONCLUSION

PHI have changed significantly over the past eight years. However, no PHI were independently associated with increased or decreased ED mortality.

Commentary on gaps in prehospital trauma care: education and bioengineering innovations to improve outcomes in hemorrhage and traumatic brain injury

Hemorrhage remains the leading cause of preventable death on the battlefield and the civilian arena. Many of these deaths occur in the prehospital setting. Traumatic brain injury also represents a major source of early mortality and morbidity in military and civilian settings. The inaugural HERETIC (HEmostatic REsuscitation and Trauma Induced Coagulopathy) Symposium convened a multidisciplinary panel of experts in prehospital trauma care to discuss what education and bioengineering advancements in the prehospital space are necessary to improve outcomes in hemorrhagic shock and traumatic brain injury. The panel identified several promising technological breakthroughs, including field point-of-care diagnostics for hemorrhage and brain injury and unique hemorrhage control options for non-compressible torso hemorrhage. Many of these technologies exist but require further advancement to be feasibly and reliably deployed in a prehospital or combat environment. The panel discussed shifting educational and training paradigms to clinical immersion experiences, particularly for prehospital clinicians. The panel discussed an important balance between pushing traditionally hospital-based interventions into the field and developing novel intervention options specifically for the prehospital environment. Advancing prehospital diagnostics may be important not only to allow more targeted applications of therapeutic options, but also to identify patients with less urgent injuries that may not need more advanced diagnostics, interventions, or transfer to a higher level of care in resource-constrained environments. Academia and industry should partner and prioritize some of the promising advances identified with a goal to prepare them for clinical field deployment to optimize the care of patients near the point of injury.

Volume replacement in the resuscitation of trauma patients with acute hemorrhage: an umbrella review

BACKGROUND

The use of intravenous fluid therapy in patients with major trauma in prehospital settings is still controversial. We conducted an umbrella review to evaluate which is the best volume expansion in the resuscitation of a hemorrhagic shock to support the development of major trauma guideline recommendations.

METHODS

We searched PubMed, Embase, and CENTRAL up to September 2022 for systematic reviews (SRs) investigating the use of volume expansion fluid on mortality and/or survival. Quality assessment was performed using AMSTAR 2 and the Certainty of the evidence was assessed with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

We included 14 SRs investigating the effects on mortality with the comparisons: use of crystalloids, blood components, and whole blood. Most SRs were judged as critically low with slight overlapping of primary studies and high consistency of results. For crystalloids, inconsistent evidence of effectiveness in 28- to 30-day survival (primary endpoint) was found for the hypertonic saline/dextran group compared with isotonic fluid solutions with moderate certainty of evidence. Pre-hospital blood component infusion seems to reduce mortality, however, as the certainty of evidence ranges from very low to moderate, we are unable to provide evidence to support or reject its use. The blood component ratio was in favor of higher ratios among all comparisons considered with moderate to very low certainty of evidence. Results about the effects of whole blood are very uncertain due to limited and heterogeneous interventions in studies included in SRs.

CONCLUSION

Hypertonic crystalloid use did not result in superior 28- to 30-day survival. Increasing evidence supports the scientific rationale for early use of high-ratio blood components, but their use requires careful consideration. Preliminary evidence is very uncertain about the effects of whole blood and further high-quality studies are required.

The SWiFT trial (Study of Whole Blood in Frontline Trauma)-the clinical and cost effectiveness of pre-hospital whole blood versus standard care in patients with life-threatening traumatic haemorrhage: study protocol for a multi-centre randomised controlled trial

BACKGROUND

Early blood transfusion improves survival in patients with life-threatening bleeding, but the optimal transfusion strategy in the pre-hospital setting has yet to be established. Although there is some evidence of benefit with the use of whole blood, there have been no randomised controlled trials exploring the clinical and cost effectiveness of pre-hospital administration of whole blood versus component therapy for trauma patients with life-threatening bleeding. The aim of this trial is to determine whether pre-hospital leukocyte-depleted whole blood transfusion is better than standard care (blood component transfusion) in reducing the proportion of participants who experience death or massive transfusion at 24 h.

METHODS

This is a multi-centre, superiority, open-label, randomised controlled trial with internal pilot and within-trial cost-effectiveness analysis. Patients of any age will be eligible if they have suffered major traumatic haemorrhage and are attended by a participating air ambulance service. The primary outcome is the proportion of participants with traumatic haemorrhage who have died (all-cause mortality) or received massive transfusion in the first 24 h from randomisation. A number of secondary clinical, process, and safety endpoints will be collected and analysed. Cost (provision of whole blood, hospital, health, and wider care resource use) and outcome data will be synthesised to present incremental cost-effectiveness ratios for the trial primary outcome and cost per quality-adjusted life year at 90 days after injury. We plan to recruit 848 participants (a two-sided test with 85% power, 5% type I error, 1-1 allocation, and one interim analysis would require 602 participants-after allowing for 25% of participants in traumatic cardiac arrest and an additional 5% drop out, the sample size is 848).

DISCUSSION

The SWiFT trial will recruit 848 participants across at least ten air ambulances services in the UK. It will investigate the clinical and cost-effectiveness of whole blood transfusion versus component therapy in the management of patients with life-threatening bleeding in the pre-hospital setting.

TRIAL REGISTRATION

ISRCTN: 23657907; EudraCT: 2021-006876-18; IRAS Number: 300414; REC: 22/SC/0072, 21 Dec 2021.

Pre-Hospital Blood Products for the Care of Bleeding Trauma Patients

BACKGROUND

Controversy surrounds the administration of blood products to severely traumatized patients before they arrive in the hospital in order to compensate for early blood loss and/or to correct coagulation disturbances that arise shortly after the traumatic event. A number of terrestrial and air rescue services have begun to provide this kind of treatment.

METHODS

This review is based on articles using the PICO framework, published from January 2001 to January 2021, that were retrieved by a selective search, with structured searching strategies and searching bundles in Medline (OVIDSP), the Cochrane Central Register of Controlled Trials (CENTRAL), and Epistemonikos. A demand analysis was carried out on the basis of data from the trauma registry of the German Society of Trauma Surgery (TR-DGU) and practical experience from program development and implementation was provided by the Bundeswehr Hospital Ulm.

RESULTS

The currently available evidence on the pre-hospital administration of blood products in the early treatment of severely injured patients is based largely on retrospective, single-center case series. Two randomized controlled trials (RCTs) concerning the early use of fresh frozen plasma concentrates have yielded partly conflicting results. Three further RCTs on the use of lyophilized plasma (lyplas), lyplas plus erythrocyte concentrate, or whole blood likewise revealed non-uniform effects on short-term and intermediate-term mortality. Our demand analysis based on data from the TR-DGU showed that 300 to 1800 patients per year in Germany could benefit from the pre-hospital administration of blood products. This might be indicated in patients who have systolic hypotension (<100 mmHg) in combination with a suspected or confirmed hemorrhage, as well as pathological shock parameters in the point-of-care diagnostic testing performed on the scene (serum base excess ≤ -2.5 mmol/L and/or serum lactate concentration >4 mmol/L).

CONCLUSION

The studies that have been published to date yield no clear evidence either for or against the early pre-hospital administration of blood products. Any treatment of this kind should be accompanied by scientific evaluation.

Prehospital Resuscitation: What Should It Be?

Prehospital resuscitation is a dynamic field now being energized by new technologies and a shift in thinking regarding intravascular resuscitation. Growing evidence discourages use of intravenous (IV) crystalloid and colloid solutions in trauma, whereas blood products, particularly whole blood, are becoming preferred. Although randomized clinical trials validating definitive resuscitative protocols are still lacking, most preclinical and clinical indicators support this approach. In addition, emerging technologies such as external and endovascular hemorrhage control devices and extracorporeal perfusion are now being used routinely, even in the prehospital setting in many countries, generating new lines of emerging investigations for trauma specialists.

The forgotten cohort-lessons learned from prehospital trauma death: a retrospective cohort study

BACKGROUND

Trauma related deaths remain a relevant public health problem, in particular in the younger male population. A significant number of these deaths occur prehospitally without transfer to a hospital. These patients, sometimes termed "the forgotten cohort", are usually not included in clinical registries, resulting in a lack of information about prehospitally trauma deaths. The aim of the present study was to compare patients who died prehospital with those who sustained life-threatening injuries in order to analyze and potentially improve prehospital strategies.

METHODS

This cohort study included all primary operations carried out by Switzerland's largest helicopter emergency medical service (HEMS) between January 1, 2011, and December 31, 2021. We included all adult trauma patients with life-threatening or fatal conditions. The outcome of this study is the vital status of the patient at the end of mission, i.e. fatal or life-threatening. Injury, rescue characteristics, and interventions of the forgotten trauma cohort, defined as patients with a fatal injury (NACA score of VII), were compared with life-threatening injuries (NACA score V and VI).

RESULTS

Of 110,331 HEMS missions, 5534 primary operations were finally analyzed, including 5191 (93.8%) life-threatening and 343 (6.2%) fatal injuries. More than two-thirds of patients (n = 3772, 68.2%) had a traumatic brain injury without a significant difference between the two groups (p > 0.05). Thoracic trauma (44.6% vs. 28.7%, p < 0.001) and abdominal trauma (22.2% vs. 16.1%, p = 0.004) were more frequent in fatal missions whereas pelvic trauma was similar between the two groups (13.4% vs. 12.9%, p = 0.788). Pneumothorax decompression rate (17.2% vs. 3.7%, p < 0.001) was higher in the forgotten cohort group and measures for bleeding control (15.2% vs. 42.7%, p < 0.001) and pelvic belt application (2.9% vs. 13.1% p < 0.001) were more common in the life-threating injury group.

CONCLUSION

Chest decompression rates and measures for early hemorrhage control are areas for potential improvement in prehospital care.

Articles on hemorrhagic shock published between 2000 and 2021: A CiteSpace-Based bibliometric analysis

Objective

To conduct a bibliometric analysis of literature on hemorrhagic shock published between 2000 and 2021 with the help of Citespace to explore the current status, hotspots and research trends in this regard, with the results presented in a visualized manner.

Methods

The data over the past 22 years were retrieved from the Web of Science (WOS) Core Collection database and downloaded as the "Full Record and Cited References". Cooperative analysis, cluster analysis, co-citation analysis, and burst analysis were performed based on the data on countries/regions, institutions, journals, authors, and keywords through Citespace.

Results

A total of 2027 articles were retrieved. The number of annual publications fluctuated but was generally on an upward trend. The United States stands out as the most productive country (989 articles), the University of Pittsburgh the most productive publishing institution (109 articles), SHOCK the most cited journal (1486 articles), TAO LI the most productive author (40 articles), DEITCH EA the most cited author (261 times of citation), hemorrhagic shock the most frequent keyword (725 times of occurrence), and "traumatic brain injury" the most covered article in keyword clustering (29 articles). The burst analysis revealed Harvard University as the institution with the highest strength value and the Journal of Trauma and Acute Care Surgery the most important journal. It was also concluded that HASAN B ALAM, AARON M WILLIAMS, and LIMIN ZHANG may continue to publish high-quality articles in the future. In the meanwhile, both "protect" and "transfusion" were considered the hotspots and trends in current research.

Conclusions

The United States has been a major contributor to the publication of the articles over the past 22 years, with the most productive publishing institution, the most cited journal, and the most cited author all coming from the US. Hemorrhagic shock, injury, resuscitation, trauma, models, activation, expression, fluid resuscitation, rats, and nitric oxide are hot topics in relevant research. According to the keyword burst analysis, the areas related to "protect" and "transfusion" may rise as the research directions in the future. However, since the hotspots in the research of hemorrhagic shock are short-lived and fast-changing, the researchers should pay more attention to the development trend in this field.

Mobile blood depots in ground ambulances in compliance with French legislation: A feasibility study

BACKGROUND

Prehospital transfusion is a way of improving the management of hemorrhagic shock. In France, prehospital transfusion is struggling to develop, both because of logistical difficulties and particularly restrictive legislation. To comply with this, we propose to store the blood products (BPs) in ground ambulances with refrigerated boxes allowing remote continuous monitoring of storage conditions, called "NelumBox" (Tec4med Lifescience GmbH). To open them, the ambulance's team needs a code that is only given by the Transfusion Center if the request meets all required regulatory criteria.

STUDY DESIGN AND METHODS

We conducted a prospective simulation-based feasibility study using dummy BPs. Two ambulances were equipped. Simulations were triggered unexpectedly, including during on-call hours. The ability to quickly access the BPs was the main judgment criterion. The quality of hemovigilance during these simulations was also examined.

RESULTS

Twenty-two simulations were performed. The ambulance's team was able to access the BPs in 100% of cases. The average waiting time for receiving the unlocking code was 5 min 27 s (SD = 2 min 12 s, MAX = 12 min 00 s). The transfusion traceability was compliant with regulations in 100% of cases. The transfusion center was able to remotely monitor BPs storage conditions for the entire duration of their stockage in the NelumBox.

DISCUSSION

The present procedure is efficient, repeatable, and fast. It guarantees a strict transfusion safety without slowdown a severe trauma management, while complying with French regulations.

Whole Blood Resuscitation and Association with Survival in Injured Patients with an Elevated Probability of Mortality

BACKGROUND

Low-titer group O whole blood (LTOWB) resuscitation is becoming common in both military and civilian settings and may represent the ideal resuscitation intervention. We sought to characterize the safety and efficacy of LTOWB resuscitation relative to blood component resuscitation.

STUDY DESIGN

A prospective, multicenter, observational cohort study was performed using 7 trauma centers. Injured patients at risk of massive transfusion who required both blood transfusion and hemorrhage control procedures were enrolled. The primary outcome was 4-hour mortality. Secondary outcomes included 24-hour and 28-day mortality, achievement of hemostasis, death from exsanguination, and the incidence of unexpected survivors.

RESULTS

A total of 1,051 patients in hemorrhagic shock met all enrollment criteria. The cohort was severely injured with >70% of patients requiring massive transfusion. After propensity adjustment, no significant 4-hour mortality difference across LTOWB and component patients was found (relative risk [RR] 0.90, 95% CI 0.59 to 1.39, p = 0.64). Similarly, no adjusted mortality differences were demonstrated at 24 hours or 28 days for the enrolled cohort. When patients with an elevated prehospital probability of mortality were analyzed, LTOWB resuscitation was independently associated with a 48% lower risk of 4-hour mortality (relative risk [RR] 0.52, 95% CI 0.32 to 0.87, p = 0.01) and a 30% lower risk of 28-day mortality (RR 0.70, 95% CI 0.51 to 0.96, p = 0.03).

CONCLUSIONS

Early LTOWB resuscitation is safe but not independently associated with survival for the overall enrolled population. When patients were selected with an elevated probability of mortality based on prehospital injury characteristics, LTOWB was independently associated with a lower risk of mortality starting at 4 hours after arrival through 28 days after injury.

The impact of prehospital whole blood on hemorrhaging trauma patients: A multi-center retrospective study

BACKGROUND

Whole blood (WB) use has become increasingly common in trauma centers across the United States for both in-hospital and prehospital resuscitation. We hypothesize that prehospital WB (pWB) use in trauma patients with suspected hemorrhage will result in improved hemodynamic status and reduced in-hospital blood product requirements.

METHODS

The institutional trauma registries of two academic level I trauma centers were queried for all patients from 2015-2019 who underwent transfusion upon arrival to the trauma bay. Patients who were dead on arrival or had isolated head injuries were excluded. Demographics, injury and shock characteristics, transfusion requirements, including massive transfusion protocol (MTP) (>10 U in 24 hours) and rapid transfusion (CAT3+) and outcomes were compared between pWB and non-pWB patients. Significantly different demographic, injury characteristics and pWB were included in univariate followed by stepwise logistic regression analysis to determine the relationship with shock index (SI). Our primary objective was to determine the relationship between pWB and improved hemodynamics or reduction in blood product utilization.

RESULTS

A total of 171 pWB and 1391 non-pWB patients met inclusion criteria. Prehospital WB patients had a lower median Injury Severity Score (17 vs. 21, p < 0.001) but higher prehospital SI showing greater physiologic disarray. Prehospital WB was associated with improvement in SI (-0.04 vs. 0.05, p = 0.002). Mortality and (LOS) were similar. Prehospital WB patients received fewer packed red blood cells, fresh frozen plasma, and platelets units across their LOS but total units and volumes were similar. Prehospital WB patients had fewer MTPs (22.6% vs. 32.4%, p = 0.01) despite a similar requirement of CAT3+ transfusion upon arrival.

CONCLUSION

Prehospital WB administration is associated with a greater improvement in SI and a reduction in MTP. This study is limited by its lack of power to detect a mortality difference. Prospective randomized controlled trials will be required to determine the true impact of pWB on trauma patients.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Association of Prehospital Transfusion With Mortality in Pediatric Trauma

Importance

Optimal hemostatic resuscitation in pediatric trauma is not well defined.

Objective

To assess the association of prehospital blood transfusion (PHT) with outcomes in injured children.

Design, Setting, and Participants

This retrospective cohort study of the Pennsylvania Trauma Systems Foundation database included children aged 0 to 17 years old who received a PHT or emergency department blood transfusion (EDT) from January 2009 and December 2019. Interfacility transfers and isolated burn mechanism were excluded. Analysis took place between November 2022 and January 2023.

Exposure

Receipt of a blood product transfusion in the prehospital setting compared with the emergency department.

Main Outcomes and Measures

The primary outcome was 24-hour mortality. A 3:1 propensity score match was developed balancing for age, injury mechanism, shock index, and prehospital Glasgow Comma Scale score. A mixed-effects logistic regression was performed in the matched cohort further accounting for patient sex, Injury Severity Score, insurance status, and potential center-level heterogeneity. Secondary outcomes included in-hospital mortality and complications.

Results

Of 559 children included, 70 (13%) received prehospital transfusions. In the unmatched cohort, the PHT and EDT groups had comparable age (median [IQR], 47 [9-16] vs 14 [9-17] years), sex (46 [66%] vs 337 [69%] were male), and insurance status (42 [60%] vs 245 [50%]). The PHT group had higher rates of shock (39 [55%] vs 204 [42%]) and blunt trauma mechanism (57 [81%] vs 277 [57%]) and lower median (IQR) Injury Severity Score (14 [5-29] vs 25 [16-36]). Propensity matching resulted in a weighted cohort of 207 children, including 68 of 70 recipients of PHT, and produced well-balanced groups. Both 24-hour (11 [16%] vs 38 [27%]) and in-hospital mortality (14 [21%] vs 44 [32%]) were lower in the PHT cohort compared with the EDT cohort, respectively; there was no difference in in-hospital complications. Mixed-effects logistic regression in the postmatched group adjusting for the confounders listed above found PHT was associated with a significant reduction in 24-hour (adjusted odds ratio, 0.46; 95% CI, 0.23-0.91) and in-hospital mortality (adjusted odds ratio, 0.51; 95% CI, 0.27-0.97) compared with EDT. The number needed to transfuse in the prehospital setting to save 1 child's life was 5 (95% CI, 3-10).

Conclusions and Relevance

In this study, prehospital transfusion was associated with lower rates of mortality compared with transfusion on arrival to the emergency department, suggesting bleeding pediatric patients may benefit from early hemostatic resuscitation. Further prospective studies are warranted. Although the logistics of prehospital blood product programs are complex, strategies to shift hemostatic resuscitation toward the immediate postinjury period should be pursued.

The females have spoken: A patient-centered national survey on the administration of emergent transfusions with the potential for future fetal harm

BACKGROUND

Traumatic hemorrhage is the leading cause of preventable death. Early in the resuscitation, only RhD-positive red blood cells are likely to be available, which poses a small risk of causing harm to a future fetus if transfused to an RhD-negative females of childbearing age (CBA), that is, 15 to 49 years old. We sought to characterize how the population, in particular females of CBA, felt about emergency blood administration vis-a-vis potential future fetal harm.

METHODS

A national survey was performed using Facebook advertisements in three waves from January 2021 to January 2022. The advertisements directed users to the survey site with seven demographic questions and four questions on accepting transfusion with differing probabilities for future fetal harm (none/any/1:100/1:10,000). Acceptance of transfusion questions were scored on 3-point Likert scale (likely/neutral/unlikely). Only completed responses by females were analyzed.

RESULTS

Advertisements were viewed 16,600,430 times by 2,169,805 people with 15,396 advertisement clicks and 2,873 surveys initiated. Most (2,256 of 2,873 [79%]) were fully completed. Majority (2,049 of 2,256 [90%]) of respondents were female. Eighty percent of females (1,645 of 2,049) were of CBA. Most females responded "likely" or "neutral" when asked whether they would accept a lifesaving transfusion if the following risk of fetal harm were present: no risk (99%), any risk (83%), 1:100 risk (85%), and 1:10,000 risk (92%). There were no differences between females of CBA versus non-CBA with respect to the likelihood of accepting lifesaving transfusion with any potential for future fetal harm ( p = 0.24).

CONCLUSION

This national survey suggests that most females would accept lifesaving transfusion even with the potential low risk of future fetal harm.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Pre-hospital blood products for hazardous area response team paramedics: A service evaluation to inform decisions on future practice

Aim

To identify the number of incidents, over a 1-year period in a single UK Ambulance Service Trust, where patients attended by Hazardous Area Response Team (HART) paramedics where eligible to receive Pre-hospital Blood Products (PHBP) but did not due to the unavailability of a suitably trained clinician.

Methods

This was a Service Evaluation using a three-stage method of filtering data to reduce bias and improve accuracy when identifying eligible cases. These stages consisted of an initial data request, a peer review filtering stage and then finally an Expert Consensus Panel review of cases to determine whether PHBP should have been administered.

Results

The consensus group considered 14 cases that would have ‘Likely’ or ‘Certainly’ have received PHBP if a suitably trained clinician was available on scene. Twelve cases involved a traumatic cause whilst the remaining two were medical. Similarly, 12 cases involved patients with spontaneous circulation whilst two patients had no pulse. South Western Ambulance Service Foundation Trust (SWASFT) Bristol HART attended eight and Exeter HART six of these cases.

Conclusion

This study reveals that across the South West of England, there were a number of patients, being attended by HART, who may potentially benefit from PHBP but are not receiving this intervention due to the unavailability of a suitably trained clinician. This could be far more in the event of a multi or mass-casualty event. HART paramedic access to PHBPs would enable more patients to access a potentially lifesaving treatment and contribute to narrowing the care gap identified in the Manchester Arena Inquiry. The authors recommend that a local pilot trial is undertaken to explore whether a HART PHBP service is feasible, sustainable, cost-effective, appropriate, and safe.

Time to early resuscitative intervention association with mortality in trauma patients at risk for hemorrhage

BACKGROUND

Hemorrhage is the leading cause of preventable death after injury. Others have shown that delays in massive transfusion cooler arrival increase mortality, while prehospital blood product resuscitation can reduce mortality. Our objective was to evaluate if time to resuscitation initiation impacts mortality.

METHODS

We combined data from the Prehospital Air Medical Plasma (PAMPer) trial in which patients received prehospital plasma or standard care and the Study of Tranexamic Acid during Air and ground Medical Prehospital transport (STAAMP) trial in which patients received prehospital tranexamic acid or placebo. We evaluated the time to early resuscitative intervention (TERI) as time from emergency medical services arrival to packed red blood cells, plasma, or tranexamic acid initiation in the field or within 90 minutes of trauma center arrival. For patients not receiving an early resuscitative intervention, the TERI was calculated based on trauma center arrival as earliest opportunity to receive a resuscitative intervention and were propensity matched to those that did to account for selection bias. Mixed-effects logistic regression assessed the association of 30-day and 24-hour mortality with TERI adjusting for confounders. We also evaluated a subgroup of only patients receiving an early resuscitative intervention as defined above.

RESULTS

Among the 1,504 propensity-matched patients, every 1-minute delay in TERI was associated with 2% increase in the odds of 30-day mortality (adjusted odds ratio [aOR], 1.020; 95% confidence interval [CI], 1.006-1.033; p < 0.01) and 1.5% increase in odds of 24-hour mortality (aOR, 1.015; 95% CI, 1.001-1.029; p = 0.03). Among the 799 patients receiving an early resuscitative intervention, every 1-minute increase in TERI was associated with a 2% increase in the odds of 30-day mortality (aOR, 1.021; 95% CI, 1.005-1.038; p = 0.01) and 24-hour mortality (aOR, 1.023; 95% CI, 1.005-1.042; p = 0.01).

CONCLUSION

Time to early resuscitative intervention is associated with morality in trauma patients with hemorrhagic shock. Bleeding patients need resuscitation initiated early, whether at the trauma center in systems with short prehospital times or in the field when prehospital time is prolonged.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Outcomes of Transfusion With Whole Blood, Component Therapy, or Both in Adult Civilian Trauma Patients: A Systematic Review and Meta-Analysis

INTRODUCTION

This systematic review and meta-analysis was conducted to compare outcomes, including transfusion volume, complications, intensive care unit length of stay, and mortality for adult civilian trauma patients transfused with whole blood (WB), components (COMP), or both (WB + COMP).

METHODS

A systematic review and meta-analysis were conducted using studies that evaluated outcomes of transfusion of WB, COMP, or WB + COMP for adult civilian trauma patients. A search of PubMed, Embase, and Cochrane from database inception to March 3, 2022 was conducted. The search resulted in 18,400 initial articles with 16 studies remaining after the removal of duplicates and screening for inclusion and exclusion criteria.

RESULTS

This study identified an increased risk of 24-h mortality with COMP versus WB + COMP (relative risk: 1.40 [1.10, 1.78]) and increased transfusion volumes of red blood cells with COMP versus WB at 6 and 24 h, respectively (-2.26 [-3.82, -0.70]; -1.94 [-3.22, -0.65] units). There were no differences in the calculated rates of infections or intensive care unit length of stay between WB and COMP, respectively (relative risks: 1.35 [0.53, 3.46]; -0.91 [-2.64, 0.83]).

CONCLUSIONS

Transfusion with WB + COMP is associated with lower 24-h mortality versus COMP and transfusion with WB is associated with a lower volume of red blood cells transfused at both 6 and 24 h. Based on these findings, greater utilization of whole blood in civilian adult trauma resuscitation may lead to improved mortality and reduced transfusion requirements.

Access to Immediately Available Balanced Blood Products in a Rural State's Trauma System

INTRODUCTION

The Arkansas Trauma System was established by law more than a dozen years ago, and all participating trauma centers are required to maintain red blood cells. Since then, there has been a paradigm shift in resuscitating exsanguinating trauma patients. Damage Control Resuscitation with balanced blood products (or whole blood) and minimal crystalloid is now the standard of care. This project aimed to determine access to balanced blood products in our state's Trauma System (TS).

METHODS

A survey of all trauma centers in the Arkansas TS was conducted, and geospatial analysis was performed. Immediately Available Balanced Blood (IABB) was defined as at least 2 units (U) of thawed plasma (TP) or never frozen plasma (NFP), 4 units of red blood cells (RBCs), 2 units of fresh frozen plasma (FFP), and 1 unit of platelets or 2 units of whole blood (WB).

RESULTS

All 64 trauma centers in the state TS completed the survey. All level I, II, and III Trauma Centers (TCs) maintain RBC, plasma, and platelets, but only half of the level II and 16% of the level III TCs have thawed or never frozen plasma. A third of level IV TCs maintain only RBCs, while only 1 had platelets, and none had thawed plasma. 85% of people in our state are within 30 min of RBCs, almost two-thirds are within 30 min of plasma (TP, NFP, or FFP) and platelets, while only a third are within 30 min of IABB. More than 90% are within an hour of plasma and platelets, while only 60% are within that time from an IABB. The median drive times for Arkansas from RBC, plasma (TP, NFP, or FFP), platelets, and an immediately available and balanced blood bank are 19, 21, 32, and 59 minutes, respectively. A lack of thawed or non-frozen plasma and platelets are the most common limitations of IABB. One level III TC in the state maintains WB, which would alleviate the limited access to IABB.

CONCLUSION

Only 16% of the trauma centers in Arkansas can provide IABB, and only 61% of the population can reach IABB within 60 minutes. Opportunities exist to reduce the time to balanced blood products by selectively distributing WB, TP, or NFP to hospitals in our state trauma system.

The European guideline on management of major bleeding and coagulopathy following trauma: sixth edition

BACKGROUND

Severe trauma represents a major global public health burden and the management of post-traumatic bleeding continues to challenge healthcare systems around the world. Post-traumatic bleeding and associated traumatic coagulopathy remain leading causes of potentially preventable multiorgan failure and death if not diagnosed and managed in an appropriate and timely manner. This sixth edition of the European guideline on the management of major bleeding and coagulopathy following traumatic injury aims to advise clinicians who care for the bleeding trauma patient during the initial diagnostic and therapeutic phases of patient management.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma included representatives from six European professional societies and convened to assess and update the previous version of this guideline using a structured, evidence-based consensus approach. Structured literature searches covered the period since the last edition of the guideline, but considered evidence cited previously. The format of this edition has been adjusted to reflect the trend towards concise guideline documents that cite only the highest-quality studies and most relevant literature rather than attempting to provide a comprehensive literature review to accompany each recommendation.

RESULTS

This guideline comprises 39 clinical practice recommendations that follow an approximate temporal path for management of the bleeding trauma patient, with recommendations grouped behind key decision points. While approximately one-third of patients who have experienced severe trauma arrive in hospital in a coagulopathic state, a systematic diagnostic and therapeutic approach has been shown to reduce the number of preventable deaths attributable to traumatic injury.

CONCLUSION

A multidisciplinary approach and adherence to evidence-based guidelines are pillars of best practice in the management of severely injured trauma patients. Further improvement in outcomes will be achieved by optimising and standardising trauma care in line with the available evidence across Europe and beyond.

Association of red blood cells and plasma transfusion versus red blood cell transfusion only with survival for treatment of major traumatic hemorrhage in prehospital setting in England: a multicenter study

BACKGROUND

In-hospital acute resuscitation in trauma has evolved toward early and balanced transfusion resuscitation with red blood cells (RBC) and plasma being transfused in equal ratios. Being able to deliver this ratio in prehospital environments is a challenge. A combined component, like leukocyte-depleted red cell and plasma (RCP), could facilitate early prehospital resuscitation with RBC and plasma, while at the same time improving logistics for the team. However, there is limited evidence on the clinical benefits of RCP.

OBJECTIVE

To compare prehospital transfusion of combined RCP versus RBC alone or RBC and plasma separately (RBC + P) on mortality in trauma bleeding patients.

METHODS

Data were collected prospectively on patients who received prehospital transfusion (RBC + thawed plasma/Lyoplas or RCP) for traumatic hemorrhage from six prehospital services in England (2018-2020). Retrospective data on patients who transfused RBC from 2015 to 2018 were included for comparison. The association between transfusion arms and 24-h and 30-day mortality, adjusting for age, injury mechanism, age, prehospital heart rate and blood pressure, was evaluated using generalized estimating equations.

RESULTS

Out of 970 recruited patients, 909 fulfilled the study criteria (RBC + P = 391, RCP = 295, RBC = 223). RBC + P patients were older (mean age 42 vs 35 years for RCP and RBC), and 80% had a blunt injury (RCP = 52%, RBC = 56%). RCP and RBC + P were associated with lower odds of death at 24-h, compared to RBC alone (adjusted odds ratio [aOR] 0.69 [95%CI: 0.52; 0.92] and 0.60 [95%CI: 0.32; 1.13], respectively). The lower odds of death for RBC + P and RCP vs RBC were driven by penetrating injury (aOR 0.22 [95%CI: 0.10; 0.53] and 0.39 [95%CI: 0.20; 0.76], respectively). There was no association between RCP or RBC + P with 30-day survival vs RBC.

CONCLUSION

Prehospital plasma transfusion for penetrating injury was associated with lower odds of death at 24-h compared to RBC alone. Large trials are needed to confirm these findings.

Resuscitation with whole blood or blood components improves survival and lessens the pathophysiological burden of trauma and haemorrhagic shock in a pre-clinical porcine model

PURPOSE

In military trauma, disaster medicine, and casualties injured in remote locations, times to advanced medical and surgical treatment are often prolonged, potentially reducing survival and increasing morbidity. Since resuscitation with blood/blood components improves survival over short pre-surgical times, this study aimed to evaluate the quality of resuscitation afforded by blood/blood products or crystalloid resuscitation over extended 'pre-hospital' timelines in a porcine model of militarily relevant traumatic haemorrhagic shock.

METHODS

This study underwent local ethical review and was done under the authority of Animals (Scientific Procedures) Act 1986. Forty-five terminally anaesthetised pigs received a soft tissue injury to the right thigh, haemorrhage (30% blood volume and a Grade IV liver injury) and fluid resuscitation initiated 30 min later [Group 1 (no fluid); 2 (0.9% saline); 3 (1:1 packed red blood cells:plasma); 4 (fresh whole blood); or 5 (plasma)]. Fluid (3 ml/kg bolus) was administered during the resuscitation period (maximum duration 450 min) when the systolic blood pressure fell below 80 mmHg. Surviving animals were culled with an overdose of anaesthetic.

RESULTS

Survival time was significantly shorter for Group 1 compared to the other groups (P < 0.05). Despite the same triggers for resuscitation when compared to blood/blood components, saline was associated with a shorter survival time (P = 0.145), greater pathophysiological burden and significantly greater resuscitation fluid volume (P < 0.0001).

CONCLUSION

When times to advanced medical care are prolonged, resuscitation with blood/blood components is recommended over saline due to the superior quality and stability of resuscitation achieved, which are likely to lead to improved patient outcomes.

Resuscitative practices and the use of low-titer group O whole blood in pediatric trauma

ABSTRACT

Increasing rates of penetrating trauma in the United States makes rapid identification of hemorrhagic shock, coagulopathy, and early initiation of balanced resuscitation in injured children of critical importance. Hemorrhagic shock begins early after injury and can be challenging to identify in children, as hypotension is a late sign that a child is on the verge of circulatory collapse and should be aggressively resuscitated. Recent data support shifting away from crystalloid and toward early resuscitation with blood products because of worse coagulopathy and clinical outcomes in injured patients resuscitated with crystalloid. Multicenter studies have found improved survival in injured children who receive balanced resuscitation with higher fresh frozen plasma: red blood cell ratios. Whole blood is an efficient way to achieve balanced resuscitation in critically injured children with limited intravenous access and decreased exposure to multiple donors. Administration of cold-stored, low-titer O-negative whole blood (LTOWB) appears to be safe in adults and children and may be associated with improved survival in children with life-threatening hemorrhage. Many pediatric centers use RhD-negative LTOWB for all female children because of the risk of hemolytic disease of the fetus and newborn (0-6%); however. there is a scarcity of LTOWB compared with the demand. Low risks of hemolytic disease of the fetus and newborn affecting a future pregnancy must be weighed against high mortality rates in delayed blood product administration in children in hemorrhagic shock. Survey studies involving key stakeholder's opinions on pediatric blood transfusion practices are underway. Existing pediatric-specific literature on trauma resuscitation is often limited and underpowered; multicenter prospective studies are urgently needed to define optimal resuscitation products and practices in injured children in an era of increasing penetrating trauma.

Pediatric traumatic hemorrhagic shock consensus conference recommendations

ABSTRACT

Hemorrhagic shock in pediatric trauma patients remains a challenging yet preventable cause of death. There is little high-quality evidence available to guide specific aspects of hemorrhage control and specific resuscitation practices in this population. We sought to generate clinical recommendations, expert consensus, and good practice statements to aid providers in care for these difficult patients.The Pediatric Traumatic Hemorrhagic Shock Consensus Conference process included systematic reviews related to six subtopics and one consensus meeting. A panel of 16 consensus multidisciplinary committee members evaluated the literature related to 6 specific topics: (1) blood products and fluid resuscitation for hemostatic resuscitation, (2) utilization of prehospital blood products, (3) use of hemostatic adjuncts, (4) tourniquet use, (5) prehospital airway and blood pressure management, and (6) conventional coagulation tests or thromboelastography-guided resuscitation. A total of 21 recommendations are detailed in this article: 2 clinical recommendations, 14 expert consensus statements, and 5 good practice statements. The statement, the panel's voting outcome, and the rationale for each statement intend to give pediatric trauma providers the latest evidence and guidance to care for pediatric trauma patients experiencing hemorrhagic shock. With a broad multidisciplinary representation, the Pediatric Traumatic Hemorrhagic Shock Consensus Conference systematically evaluated the literature and developed clinical recommendations, expert consensus, and good practice statements concerning topics in traumatically injured pediatric patients with hemorrhagic shock.

Use of whole blood deployment programs for mass casualty incidents: South Texas experience in regional response and preparedness

INTRODUCTION

Firearm-related deaths have become the leading cause of death in adolescents and children. Since the Sutherland Springs, TX mass casualty incident (MCI), the Southwest Texas Regional Advisory Council for trauma instituted a prehospital whole blood (WB) program and blood deployment program for MCIs.

METHODS

The program was adopted statewide by the Texas Emergency Medical Task Force, of which Southwest Texas Regional Advisory Council is the lead for Emergency Medical Task Force 8. The recent active shooter MCI in Uvalde, TX was the first time the MCI blood deployment program had been used. To our knowledge, no other similar programs exist in this or any other country.

RESULTS

On May 24, 2022, 19 children and 2 adults were killed at an MCI in Uvalde, TX. The MCI WB deployment protocol was initiated, and South Texas Blood and Tissue Center prepared 15 U of low-titer O-positive whole blood and 10 U of leukoreduced O packed cells. The deployed blood arrived at Uvalde Memorial Hospital within 67 minutes. One of the pediatric patients sustained multiple gunshots to the chest and extremities. The child was hypotensive and received 2 U of leukoreduced O packed cells, one at the initial hospital and another during transport. On arrival, the patient required 2 U of low-titer O-positive whole blood and underwent a successful hemorrhage control operation. The remaining blood was returned to South Texas Blood and Tissue Center for distribution.

CONCLUSION

Multiple studies have shown the association of early blood product resuscitation and improved mortality, with WB being the ideal resuscitative product for many. The ongoing efforts in South Texas serve as a model for development of similar programs throughout the country to reduce preventable deaths. This event represents the first ever successful deployment of WB to the site of an MCI related to a school shooting in the modern era.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level V.

Modelling the outcomes of different red blood cell transfusion strategies for the treatment of traumatic haemorrhage in the prehospital setting in the United Kingdom

BACKGROUND AND OBJECTIVES

The limited supply and increasing demand of group O RhD-negative red blood cells (RBCs) have resulted in other transfusion strategies being explored by blood services that carry potential risks but may still provide an overall benefit to patients. Our aim was to analyse the potential economic benefits of prehospital transfusion (PHT) against no PHT.

MATERIALS AND METHODS

The impact of three PHT strategies (RhD-negative RBC, RhD-positive RBC and no transfusion) on quality-adjusted-life-years (QALYs) of all United Kingdom trauma patients in a given year and the subset of patients considered most at risk (RhD-negative females <50 years old), was modelled.

RESULTS

For the entire cohort and the subset of patients, transfusing RhD-negative RBCs generated the most QALYs (141,899 and 2977, respectively), followed by the RhD-positive RBCs (141,879.8 and 2958.8 respectively), and no prehospital RBCs (119,285 and 2503 respectively). The QALY difference between RhD-negative and RhD-positive policies was smaller (19.2, both cohorts) than RhD-positive and no RBCs policies in QALYs term (22,600 all cohort, 470 for a subset), indicating that harms from transfusing RhD-positive RBCs are lower than harms associated with no RBC transfusion. A survival increase from PHT of 0.02% (entire cohort) and 0.7% (subset cohort) would still make the RhD-positive strategy better in QALYs terms than no PHT.

CONCLUSION

While the use of RhD-positive RBCs carries risks, the benefits measured in QALYs are higher than if no PHT are administered, even for women of childbearing potential. Group O RhD-positive RBCs could be considered when there is a national shortage of RhD-negative RBCs.

Coagulopathy management of multiple injured patients - a comprehensive literature review of the European guideline 2019

The European guideline on the management of trauma-induced major bleeding and coagulopathy summarises the most relevant recommendations for trauma coagulopathy management. The management of trauma-induced major bleeding should interdisciplinary follow algorithms which distinguish between life-threatening and non-life-threatening bleeding. Point-of-care viscoelastic methods (VEM) assist target-controlled haemostatic treatment. Neither conventional coagulation assays nor VEM should delay treatment in life-threatening trauma-induced bleeding. Adjustments may be rational due to local circumstances, including the availability of blood products, pharmaceuticals, and employees.

Reducing Firearm Injury and Death in the United States

Firearms injury is a major cause of American morbidity and mortality. Although the firearm is a common vector, the intentions with which it is used represent a wide array of social ills-suicide, community violence, domestic violence, mass shootings, legal intervention, and unintended injury. The political and social underpinnings of this epidemic are inseparable from its prevention measures. Surgeons have an important role in firearm policy, research, prehospital and hospital advances, trauma survivor networks, and hospital-based violence prevention programs. It is only through interdisciplinary, multilevel, evidence-based prevention measures that the tides will turn on American firearm injury.

Innate immunity and immunotherapy for hemorrhagic shock

Hemorrhagic shock (HS) is a shock result of hypovolemic injury, in which the innate immune response plays a central role in the pathophysiology ofthe severe complications and organ injury in surviving patients. During the development of HS, innate immunity acts as the first line of defense, mediating a rapid response to pathogens or danger signals through pattern recognition receptors. The early and exaggerated activation of innate immunity, which is widespread in patients with HS, results in systemic inflammation, cytokine storm, and excessive activation of complement factors and innate immune cells, comprised of type II innate lymphoid cells, CD4⁺ T cells, natural killer cells, eosinophils, basophils, macrophages, neutrophils, and dendritic cells. Recently, compelling evidence focusing on the innate immune regulation in preclinical and clinical studies promises new treatment avenues to reverse or minimize HS-induced tissue injury, organ dysfunction, and ultimately mortality. In this review, we first discuss the innate immune response involved in HS injury, and then systematically detail the cutting-edge therapeutic strategies in the past decade regarding the innate immune regulation in this field; these strategies include the use of mesenchymal stem cells, exosomes, genetic approaches, antibody therapy, small molecule inhibitors, natural medicine, mesenteric lymph drainage, vagus nerve stimulation, hormones, glycoproteins, and others. We also reviewed the available clinical studies on immune regulation for treating HS and assessed the potential of immune regulation concerning a translation from basic research to clinical practice. Combining therapeutic strategies with an improved understanding of how the innate immune system responds to HS could help to identify and develop targeted therapeutic modalities that mitigate severe organ dysfunction, improve patient outcomes, and reduce mortality due to HS injury.

Prehospital synergy: Tranexamic acid and blood transfusion in patients at risk for hemorrhage

BACKGROUND

Growing evidence supports improved survival with prehospital blood products. Recent trials show a benefit of prehospital tranexamic acid (TXA) administration in select subgroups. Our objective was to determine if receiving prehospital packed red blood cells (pRBC) in addition to TXA improved survival in injured patients at risk of hemorrhage.

METHODS

We performed a secondary analysis of all scene patients from the Study of Tranexamic Acid during Air and ground Medical Prehospital transport trial. Patients were randomized to prehospital TXA or placebo. Some participating EMS services utilized pRBC. Four resuscitation groups resulted: TXA, pRBC, pRBC+TXA, and neither. Our primary outcome was 30-day mortality and secondary outcome was 24-hour mortality. Cox regression tested the association between resuscitation group and mortality while adjusting for confounders.

RESULTS

A total of 763 patients were included. Patients receiving prehospital blood had higher Injury Severity Scores in the pRBC (22 [10, 34]) and pRBC+TXA (22 [17, 36]) groups than the TXA (12 [5, 21]) and neither (10 [4, 20]) groups (p < 0.01). Mortality at 30 days was greatest in the pRBC+TXA and pRBC groups at 18.2% and 28.6% compared with the TXA only and neither groups at 6.6% and 7.4%, respectively. Resuscitation with pRBC+TXA was associated with a 35% reduction in relative hazards of 30-day mortality compared with neither (hazard ratio, 0.65; 95% confidence interval, 0.45-0.94; p = 0.02). No survival benefit was observed in 24-hour mortality for pRBC+TXA, but pRBC alone was associated with a 61% reduction in relative hazards of 24-hour mortality compared with neither (hazard ratio, 0.39; 95% confidence interval, 0.17-0.88; p = 0.02).

CONCLUSION

For injured patients at risk of hemorrhage, prehospital pRBC+TXA is associated with reduced 30-day mortality. Use of pRBC transfusion alone was associated with a reduction in early mortality. Potential synergy appeared only in longer-term mortality and further work to investigate mechanisms of this therapeutic benefit is needed to optimize the prehospital resuscitation of trauma patients.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Prehospital Lyophilized Plasma Transfusion for Trauma-Induced Coagulopathy in Patients at Risk for Hemorrhagic Shock: A Randomized Clinical Trial

IMPORTANCE

Blood transfusion is a mainstay of therapy for trauma-induced coagulopathy, but the optimal modalities for plasma transfusion in the prehospital setting remain to be defined.

OBJECTIVE

To determine whether lyophilized plasma transfusion can reduce the incidence of trauma-induced coagulopathy compared with standard care consisting of normal saline infusion.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial was performed at multiple centers in France involving prehospital medical teams. Participants included 150 adults with trauma who were at risk for hemorrhagic shock and associated coagulopathy between April 1, 2016, and September 30, 2019, with a 28-day follow-up. Data were analyzed from November 1, 2019, to July 1, 2020.

INTERVENTION

Patients were randomized in a 1:1 ratio to receive either plasma or standard care with normal saline infusion (control).

MAIN OUTCOMES AND MEASURES

The primary outcome was the international normalized ratio (INR) on arrival at the hospital. Secondary outcomes included the need for massive transfusion and 30-day survival. As a safety outcome, prespecified adverse events included thrombosis, transfusion-related acute lung injury, and transfusion-associated circulatory overload.

RESULTS

Among 150 randomized patients, 134 were included in the analysis (median age, 34 [IQR, 26-49] years; 110 men [82.1%]), with 68 in the plasma group and 66 in the control group. Median INR values were 1.21 (IQR, 1.12-1.49) in the plasma group and 1.20 (IQR, 1.10-1.39) in the control group (median difference, -0.01 [IQR, -0.09 to 0.08]; P = .88). The groups did not differ significantly in the need for massive transfusion (7 [10.3%] vs 4 [6.1%]; relative risk, 1.78 [95% CI, 0.42-8.68]; P = .37) or 30-day survival (hazard ratio for death, 1.07 [95% CI, 0.44-2.61]; P = .89). In the full intention-to-treat population (n = 150), the groups did not differ in the rates of any of the prespecified adverse events.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial including severely injured patients at risk for hemorrhagic shock and associated coagulopathy, prehospital transfusion of lyophilized plasma was not associated with significant differences in INR values vs standard care with normal saline infusion. Nevertheless, these findings show that lyophilized plasma transfusion is a feasible and safe procedure for this patient population.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02736812.

Attitudes of American adult women toward accepting RhD-mismatched transfusions in bleeding emergencies

BACKGROUND

There is an increasing literature demonstrating the benefits of prehospital and early in-hospital transfusions. RhD-positive products might only be available during these phases, which could pose consequences for future pregnancies if D-alloimmunization occurs. This survey measured the willingness of females to accept urgent but incompatible transfusions in light of the potential for future pregnancy complications.

METHODS

A survey was designed to assess the willingness of females ≥18 years of age to accept urgent incompatible transfusions when different absolute risk reductions in maternal mortality were presented along with a static rate of 0.3%-4.0% risk of harm to future pregnancies. The survey was sent electronically to women who are part of the Washington University Research Enhancement Core database.

RESULTS

A total of 4896 delivered survey email invitations were distributed and 325 (6.6%) responses were received; 16 responses were excluded leaving 309 responses for analysis. Most of the responding women were White, college-educated, and lived in Missouri. At least 90% of the respondents would accept an urgent incompatible transfusion when the absolute risk reduction in maternal mortality was ≥4%. Women without a college degree, who lived in Illinois, who were not able to have children appeared to be less willing than their counterparts to receive an incompatible transfusion when the absolute risk reduction in maternal mortality was low.

CONCLUSION

This survey demonstrated that adult women are highly likely to be open to accept urgent incompatible blood transfusions during a bleeding emergency when the absolute risk reduction in maternal mortality was ≥4%.

Rate of D-alloimmunization in trauma does not depend on the number of RhD-positive units transfused: The BEST collaborative study

BACKGROUND

Evidence indicates the life-saving benefits of early blood product transfusion in severe trauma resuscitation. Many of these products will be RhD-positive, so understanding the D-alloimmunization rate is important.

METHODS

This was a multicenter, retrospective study whereby injured RhD-negative patients between 18-50 years of age who received at least one unit of RhD-positive red blood cells (RBC) or low titer group O whole blood (LTOWB) during their resuscitation between 1 January, 2010 through 31 December, 2019 were identified. If an antibody detection test was performed ≥14 days after the index RhD-positive transfusion then basic demographic information was collected, including whether the patient became D-alloimmunized. The overall D-alloimmunization rate, and the rate stratified by the number of units transfused, were calculated.

RESULTS

Data were collected from nine institutions. Five institutions reported fewer than 10 eligible patients each and were excluded. From the remaining four institutions, all from the USA, there were 235 eligible patients; 77 (random effects estimate: 32.7%; 95% CI: 19.1-50.1%) became D-alloimmunized. Three of the institutions reported D-alloimmunization rates ≥38.6%, while the remaining institution's rate was 12.2%. In both random and fixed-effects models, the rate of D-alloimmunization was not significantly different between those who received one RhD-positive unit and those who received multiple RhD-positive units.

CONCLUSION

In this large, multicenter study of injured patients, the overall rate of D-alloimmunization fell within the range previously reported. The rate of D-alloimmunization did not increase as the number of transfused RhD-positive units increased. These data can help to inform RhD type selection decisions.

Initial experiences of prehospital blood product transfusions between 2016 and 2020 in Päijät-Häme hospital district, Finland

Background

Treating hemorrhaging patients with prehospital blood product transfusions (PHBT) narrows transfusion delays and potentially benefits the patient. We describe our initial experiences of PHBT in a ground-based emergency medical service (EMS), where the transfusion protocol covers both traumatic and nontraumatic hemorrhaging patients.

Methods

A descriptive retrospective analysis was performed on the records of all the patients receiving red blood cells, freeze-dried plasma, or both during prehospital care from September 2016 to December 2020. The delays of PHBT and the effects on patients’ vital signs were analyzed and reported as the median and interquartile range (IQR) and analyzed using a Wilcoxon Signed rank test.

Results

65 patients received prehospital blood product transfusions (PHBT), 29 (45%) were non-traumatic, and 36 (55%) traumatic. The main two reasons for PHBT were blunt trauma (n = 30, 46%) and gastrointestinal hemorrhage (n = 20, 31%). The median time from the emergency call to the start of PHBT was 54 min (IQR 38), and the transfusion began on a median of 61 min (IQR 42) before arrival at the hospital. The median systolic blood pressure improved from a median 76.5 mmHg (IQR 36.5) before transfusion to a median of 116.60 mmHg (IQR 26.5) (p < 0.001) on arrival to the hospital. No transfusion-related severe adverse events were noted.

Conclusions

Starting PHBT in ground-based EMS is a feasible and viable option. The PHBT began significantly earlier than it would have started on arrival to the hospital, and it seems to be safe and improve patients’ physiology.

Study approval

D/2603/07.01.04.05/2019.

There and Back Again: The Once and Current Developments in Donor-Derived Platelet Products for Products for Hemostatic Therapy

Over 100 years ago, Duke transfused whole blood to a thrombocytopenic patient to raise the platelet count and prevent bleeding. Since then, platelet transfusions have undergone numerous modifications from whole blood-derived platelet-rich plasma to apheresis-derived platelet concentrates. Similarly, the storage time and temperature have changed. The mandate to store platelets for a maximum of 5-7 days at room temperature has been challenged by recent clinical trial data, ongoing difficulties with transfusion-transmitted infections, and recurring periods of shortages, further exacerbated by the COVID-19 pandemic. Alternative platelet storage approaches are as old as the first platelet transfusions. Cold-stored platelets may offer increased storage times (days) and improved hemostatic potential at the expense of reduced circulation time. Frozen (cryopreserved) platelets extend the storage time to years but require storage at -80 °C and thawing before transfusion. Lyophilized platelets can be powder-stored for years at room temperature and reconstituted within minutes in sterile water but are probably the least explored alternative platelet product to date. Finally, whole blood offers the hemostatic spectrum of all blood components but has challenges, such as ABO incompatibility. While we know more than ever before about the in vitro properties of these products, clinical trial data on these products are accumulating. The purpose of this review is to summarize the findings of recent preclinical and clinical studies on alternative, donor-derived platelet products.

Whole blood use in trauma resuscitation: targeting prehospital transfusion

PURPOSE OF REVIEW

Trauma resuscitation management has evolved over the years with a more nuanced understanding of the injured patient's physiologic state of shock. The purpose of this review is to discuss the role of whole blood administration in the prehospital setting in the resuscitation of the trauma patient.

RECENT FINDINGS

In traumatically injured patients, whole blood administration initiated in the prehospital setting may improve early shock severity, coagulopathy, and survival when used over traditional resuscitation fluids such as crystalloid administration or component therapy.

SUMMARY

The timing of resuscitation and its components deserve special attention when improving outcomes for trauma patients requiring massive transfusion.

Transfusion Ratios and Deficits in Injured Children With Life-Threatening Bleeding

OBJECTIVES

To assess the impact of plasma and platelet ratios and deficits in injured children with life-threatening bleeding.

DESIGN

Secondary analysis of the MAssive Transfusion epidemiology and outcomes In Children study dataset, a prospective observational study of children with life-threatening bleeding events.

SETTING

Twenty-four childrens hospitals in the United States, Canada, and Italy.

PATIENTS

Injured children 0-17 years old who received greater than 40 mL/kg total blood products over 6 hours or were transfused under activation of massive transfusion protocol.

INTERVENTION/EXPOSURE

Weight-adjusted blood product volumes received during the bleeding event were recorded. Plasma:RBC ratio (plasma/RBC weight-adjusted volume in mL/kg) and platelet:RBC ratio (platelet/RBC weight-adjusted volume in mL/kg) were analyzed. Plasma deficit was calculated as RBC mL/kg - plasma mL/kg; platelet deficit was calculated as RBC mL/kg - platelet mL/kg.

MEASUREMENTS AND MAIN RESULTS

Of 191 patients analyzed, median (interquartile range) age was 10 years (5-15 yr), 61% were male, 61% blunt mechanism, and median (interquartile range) Injury Severity Score was 29 (24-38). After adjusting for Pediatric Risk of Mortality score, cardiac arrest, use of vasoactive medications, and blunt mechanism, a high plasma:RBC ratio (> 1:2) was associated with improved 6-hour survival compared with a low plasma:RBC ratio (odds ratio [95% CI] = 0.12 [0.03-0.52]; p = 0.004). Platelet:RBC ratio was not associated with survival. After adjusting for age, Pediatric Risk of Mortality score, cardiac arrest, and mechanism of injury, 6-hour and 24-hour mortality were increased in children with greater plasma deficits (10% and 20% increased odds of mortality for every 10 mL/kg plasma deficit at 6 hr [p = 0.04] and 24 hr [p = 0.01], respectively); 24-hour mortality was increased in children with greater platelet deficits (10% increased odds of 24-hr mortality for every 10 mL/kg platelet deficit [p = 0.02)]).

CONCLUSIONS

In injured children, balanced resuscitation may improve early survival according to this hypothesis generating study. Multicenter clinical trials are needed to assess whether clinicians should target ratios and deficits as optimal pediatric hemostatic resuscitation practice.