Zero preventable deaths after traumatic injury: An achievable goal

Pediatric trauma and resuscitation: optimizing care in an evolving landscape

PURPOSE OF REVIEW

Penetrating firearm-related injury has increased mortality rates in children in the USA. This article summarizes trends in pediatric injury patterns, the unique coagulation system of infants, and key components of hemostatic resuscitation in children.

RECENT FINDINGS

Firearm-associated penetrating trauma increased mortality and led to higher rates of pediatric massive transfusions. Patients may be the victim of previous gun violence or live with an adult who purchased a firearm for the first time during the COVID-19 pandemic. Platelet dysfunction and hypocalcemia are important considerations that may lead to higher transfusion requirements if not addressed. Pediatric massive transfusion protocols have become more standardized, and the use of whole blood has increased. Low-titer group O whole blood has shown benefit to improve coagulopathy and shock-associated indices when compared with conventional component therapy.

SUMMARY

Traumatic hemorrhage is potentially life-threatening in children and requires prompt hemostatic resuscitation. Massive transfusion protocols that target trauma-induced coagulopathy and account for the unique pediatric coagulation system are imperative. Ongoing and future research is important to standardize pediatric resuscitation practices.

Whole Blood Requirements in Civilian Trauma Resuscitation: Implications for Blood Inventory Program

INTRODUCTION

It is unclear what volume of whole blood (WB) a center may need to maintain an adequate inventory. This study aimed to determine the current WB requirements, using the military concept of WB equivalent (WBE), across different levels of trauma centers.

METHODS

This is a retrospective analysis of the American College of Surgeons Trauma Quality Improvement Program database (2017-2018), including adult (≥16 ys) trauma patients who received massive transfusions. The primary outcome was WBE, which was calculated for each patient as units of WB plus equivalent component product units (1 red blood cell + 1 fresh frozen plasma + 0.2 platelet).

RESULTS

A total of 9976 patients were identified. The mean (standard deviation) age was 41 (18), and 77.8% were male. The mean initial shock index was 1.2 (1.1), with the mean (standard deviation) systolic blood pressure of 104 (40) during resuscitation in the emergency department. The median (interquartile range) 24-h packed red blood cell, fresh frozen plasma, platelet, and WB were 12 (8-17), 8 (5-13), 2 (1-3), and 2 (1-3), respectively. The median 24-h WBE transfusion was 10 units, 75% of patients required 14 units or less, and 90% required 17 units or less. There was no difference in terms of median WBE transfusions across different levels of trauma centers (Level I: 10U, Level II: 10U, Level III and lower: 10U, P = 0.126).

CONCLUSIONS

On a nationwide scale, 75% of patients with massive transfusions received a maximum of 14 WBE units. These findings provide important insights to trauma centers on the volume of WB required to maintain adequate WB inventory to effectively support the successful implementation of future WB programs.

Challenges in Saving Trauma Patients in Seoul Based on the 2016-2020 Community-Based Severe Trauma Survey

Background/Objectives: The preventable trauma death rate (PTDR) reflects the quality of trauma management systems. In the Republic of Korea, the PTDR in Seoul, the capital city, decreased from 30.8% in 2015 to 20.4% in 2019. However, it remains the highest in the country. In contrast, Gyeonggi-Incheon, which includes Gyeonggi Province and Incheon Metropolitan City surrounding Seoul, had the lowest nationwide PTDR (27.4% in 2015 to 13.1% in 2019). This study aimed to investigate the characteristics and in-hospital mortality risk factors for patients with trauma in Seoul and Gyeonggi-Incheon. Methods: This retrospective cohort study used data from a 2016 to 2020 Community-Based Severe Trauma Survey. Among 237,616 patients, 24,448 were included in the study after applying the inclusion and exclusion criteria. Results: The proportions of the population with motor vehicle and workers' compensation insurance increased with increasing injury severity in both regions. The injury severity score (ISS) was significantly higher in Gyeonggi-Incheon in the ISS < 9 and ISS 9-15 groups. Across all hospital levels, the proportion of patients who visited regional trauma centers in Seoul was low across all three ISS groups (0.2%[n = 26], 0.6%[n = 23], and 1.9%[n = 56] for ISS < 9, ISS 9-15, and ISS > 15, respectively). Conversely, in Gyeonggi-Incheon, the proportion of patients who visited regional trauma centers increased as injury severity increased across all three ISS groups (37.3%[n = 1404], 50.6%[n = 732], and 64.4%[n = 856] for ISS < 9, ISS 9-15, and ISS > 15, respectively). In Seoul, the identified in-hospital mortality risk factors included age, National Health Insurance (NHI) loss, other insurance, ISS, regional and local emergency centers or institutes, and the number of angioembolizations. In Gyeonggi-Incheon, the in-hospital mortality risk factors included age, ISS, falls and slippage, and the number of angioembolizations. Conclusions: The unique in-hospital mortality risk factors in Seoul compared with those in Gyeonggi-Incheon include transfers to regional emergency centers (ISS > 15), local emergency centers or institutes (ISS > 15), NHI loss (ISS 9-15 and ISS > 15), and the use of other insurance (ISS > 15).

Therapeutic delivery of oxygen using artificial oxygen carriers demonstrates the possibility of treating a wide range of diseases

Artificial oxygen carriers have emerged as potential substitutes for red blood cells in situations of major blood loss, including accidents, surgical procedures, trauma, childbirth, stomach ulcers, hemorrhagic shock, and blood vessel ruptures which can lead to sudden reduction in blood volume. The therapeutic delivery of oxygen utilizing artificial oxygen carriers as red blood cell substitutes presents a promising avenue for treating a spectrum of disease models. Apart from that, the recent advancement of artificial oxygen carriers intended to supplant conventional blood transfusions draws significant attention due to the exigencies of warfare and the ongoing challenges posed by the COVID-19 pandemic. However, there is a pressing need to formulate stable, non-toxic, and immunologically inert oxygen carriers. Even though numerous challenges are encountered in the development of artificial oxygen carriers, their applicability extends to various medical treatments, encompassing elective and cardiovascular surgeries, hemorrhagic shock, decompression illness, acute stroke, myocardial infarction, sickle cell crisis, and proficient addressing conditions such as cerebral hypoxia. Therefore, this paper provides an overview of therapeutic oxygen delivery using assorted types of artificial oxygen carriers, including hemoglobin-based, perfluorocarbon-based, stem cell-derived, and oxygen micro/nanobubbles, in the treatment of diverse disease models. Additionally, it discusses the potential side effects and limitations associated with these interventions, while incorporating completed and ongoing research and recent clinical developments. Finally, the prospective solutions and general demands of the perfect artificial oxygen carriers were anticipated to be a reference for subsequent research endeavors.

Pre-hospital Tourniquet Use in Adolescent and Pediatric Traumatic Hemorrhage: A National Study

BACKGROUND

Tourniquet placement (TP) is a crucial intervention to control hemorrhage, but limited literature exists for use in children. This study aimed to evaluate the effectiveness of tourniquet application by different providers (Emergency Medical Services (EMS), first responder (FR), and bystanders), hypothesizing equivalent impact on outcomes for pediatric trauma patients for all providers.

METHODS

Data from the National EMS Information Systems (NEMSIS) 2017-2020 was used to examine patients 0-19 years old and assess the outcomes of tourniquet application. We considered demographics, procedure success, timing of TP relative to EMS arrival, revised trauma score (RTS), and improvement in acuity. Multivariable logistic regression models were employed to predict initial acuity and likelihood of acuity improvement after TP, while accounting for patient and provider-related variables.

RESULTS

301 patients were included with a median age of 17 and 86.7 % male. TP by any provider before EMS transport arrival was associated with reduced odds of critical acuity upon EMS arrival (OR = 0.84, CI = 0.76-0.94, p = 0.003). After EMS arrival, bystander- and FR-placed tourniquets were associated with increased odds of improved acuity compared to EMS-placed tourniquets (OR = 1.90, CI = 1.06-3.41, p = 0.03). There was only one TP failure (0.43 %) in the EMS group. TP failure was associated with decreased odds of acuity improvement (OR = 0.62, CI = 0.44-0.86, p = 0.005).

CONCLUSION

Early TP for pediatric traumatic hemorrhage is crucial. Failures were rare. Placement by bystanders and FR were associated with improved acuity when controlling for other factors including RTS and EMS arrival time. These findings emphasize the importance of training on TP for all providers in prehospital settings.

LEVEL OF EVIDENCE

IV.

The impact of simulation-based training on medical students' whole blood transfusion abilities

BACKGROUND

Whole blood transfusion has been found to increase the likelihood of patient survival within both military and civilian medicine contexts. However, no whole blood transfusion training curriculum currently exists within undergraduate or graduate medical education in the United States. The purpose of our study was to: (1) determine the impact of simulation-based training on medical students' abilities to conduct whole blood transfusions; and (2) determine the impact of simulation-based training on medical students' confidence in conducting whole blood transfusions.

STUDY DESIGN AND METHODS

We assessed 157 third-year military medical students' ability to conduct whole blood transfusion before and after Operation Gunpowder, a 2-day high-fidelity prolonged casualty care simulation. We conducted a paired samples t-test to compare the students' pre- and post-simulation performance scores as well as self-reported confidence and stress ratings.

RESULTS

There was a significant difference in students' scores at the beginning of the course (M = 20.469, SD 6.40675) compared to their scores at the end of the course (M = 30.361, SD = 2.10053); t(155) = -18.833, p < .001. The effect size for this analysis (d = 6.56) was large. There was a significant difference (p < .001) between the pre- and post-ratings for all self-reported confidence and stress survey items.

DISCUSSION

Our results suggest that simulation-based training is an effective means of training medical students to conduct whole blood transfusiontraining in a limited resource simulated environment where blood inventories may be limited.

Trauma patients have reduced ex vivo flow-dependent platelet hemostatic capacity in a microfluidic model of vessel injury

Trauma is the leading cause of death in individuals up to 45 years of age. Alterations in platelet function are a critical component of trauma-induced coagulopathy (TIC), yet these changes and the potential resulting dysfunction is incompletely understood. The lack of clinical assays available to explore platelet function in this patient population has hindered detailed understanding of the role of platelets in TIC. The objective of this study was to assess trauma patient ex vivo flow-dependent platelet hemostatic capacity in a microfluidic model. We hypothesized that trauma patients would have flow-regime dependent alterations in platelet function. Blood was collected from trauma patients with level I activations (N = 34) within 60 min of hospital arrival, as well as healthy volunteer controls (N = 10). Samples were perfused through a microfluidic model of injury at venous and arterial shear rates, and a subset of experiments were performed after incubation with fluorescent anti-CD41 to quantify platelets. Complete blood counts were performed as well as plasma-based assays to quantify coagulation times, fibrinogen, and von Willebrand factor (VWF). Exploratory correlation analyses were employed to identify relationships with microfluidic hemostatic parameters. Trauma patients had increased microfluidic bleeding times compared to healthy controls. While trauma patient samples were able to deposit a substantial amount of clot in the model injury site, the platelet contribution to microfluidic hemostasis was attenuated. Trauma patients had largely normal hematology and plasma-based coagulation times, yet had elevated D-Dimer and VWF. Venous microfluidic bleeding time negatively correlated with VWF, D-Dimer, and mean platelet volume (MPV), while arterial microfluidic bleeding time positively correlated with oxygenation. Arterial clot growth rate negatively correlated with red cell count, and positively with mean corpuscular volume (MCV). We observed changes in clot composition in trauma patient samples reflected by significantly diminished platelet contribution, which resulted in reduced hemostatic function in a microfluidic model of vessel injury. We observed a reduction in platelet clot contribution under both venous and arterial flow ex vivo in trauma patient samples. While our population was heterogenous and had relatively mild injury severity, microfluidic hemostatic parameters correlated with different patient-specific data depending on the flow setting, indicating potentially differential mechanistic pathways contributing to platelet hemostatic capacity in the context of TIC. These data were generated with the goal of identifying key features of platelet dysfunction in bleeding trauma patients under conditions of flow and to determine if these features correlate with clinically available metrics, thus providing preliminary surrogate markers of physiological platelet dysfunction to be further studied across larger cohorts. Future studies will continue to explore those relationships and further define mechanisms of TIC and their relationship with patient outcomes.

Prospective validation of a hospital triage predictive model to decrease undertriage: an EAST multicenter study

Background

Tiered trauma team activation (TTA) allows systems to optimally allocate resources to an injured patient. Target undertriage and overtriage rates of <5% and <35% are difficult for centers to achieve, and performance variability exists. The objective of this study was to optimize and externally validate a previously developed hospital trauma triage prediction model to predict the need for emergent intervention in 6 hours (NEI-6), an indicator of need for a full TTA.

Methods

The model was previously developed and internally validated using data from 31 US trauma centers. Data were collected prospectively at five sites using a mobile application which hosted the NEI-6 model. A weighted multiple logistic regression model was used to retrain and optimize the model using the original data set and a portion of data from one of the prospective sites. The remaining data from the five sites were designated for external validation. The area under the receiver operating characteristic curve (AUROC) and the area under the precision-recall curve (AUPRC) were used to assess the validation cohort. Subanalyses were performed for age, race, and mechanism of injury.

Results

14 421 patients were included in the training data set and 2476 patients in the external validation data set across five sites. On validation, the model had an overall undertriage rate of 9.1% and overtriage rate of 53.7%, with an AUROC of 0.80 and an AUPRC of 0.63. Blunt injury had an undertriage rate of 8.8%, whereas penetrating injury had 31.2%. For those aged ≥65, the undertriage rate was 8.4%, and for Black or African American patients the undertriage rate was 7.7%.

Conclusion

The optimized and externally validated NEI-6 model approaches the recommended undertriage and overtriage rates while significantly reducing variability of TTA across centers for blunt trauma patients. The model performs well for populations that traditionally have high rates of undertriage.

Level of evidence

2.

Receipt of RhD-positive whole blood for life-threatening bleeding in female children: A survey in alloimmunized mothers regarding minimum acceptable survival benefit relative to risk of maternal alloimmunization to anti-D

BACKGROUND

Low-titer group O whole blood (LTOWB) for treatment of hemorrhagic shock sometimes necessitates transfusion of RhD-positive units due to short supply of RhD-negative LTOWB. Practitioners must choose between using RhD-positive LTOWB when RhD-negative is unavailable against the risk to a female of childbearing potential of becoming RhD-alloimmunized, risking hemolytic disease of the fetus and newborn (HDFN) in future children, or using component therapy with RhD-negative red cells. This survey asked females with a history of red blood cell (RBC) alloimmunization about their risk tolerance of RhD alloimmunization compared to the potential for improved survival following transfusion of RhD-positive blood for an injured RhD negative female child.

STUDY DESIGN AND METHODS

A survey was administered to RBC alloimmunized mothers. Respondents were eligible if they were living in the United States with at least one red cell antibody known to cause HDFN and if they had at least one RBC alloimmunized pregnancy.

RESULTS

Responses from 107 RBC alloimmmunized females were analyzed. There were 32/107 (30%) with a history of severe HDFN; 12/107 (11%) had a history of fetal or neonatal loss due to HDFN. The median (interquartile range) absolute improvement in survival at which the respondents would accept RhD-positive transfusions for a female child was 4% (1%-14%). This was not different between females with and without a history of severe or fatal HDFN (p = .08 and 0.38, respectively).

CONCLUSION

Alloimmunized mothers would accept the risk of D-alloimmunization in a RhD-negative female child for improved survival in cases of life-threatening bleeding.

Performance Improvement Program Review of Institutional Massive Transfusion Protocol Adherence: An Opportunity for Improvement

BACKGROUND

Given the acuity of patients who receive MTPs and the resources they require, MTPs are a compelling target for performance improvement. This study evaluated adherence with our MTP's plasma:red blood cell ratio (FFPR) of 1:2 and platelet:red blood cell ratio (PLTR) of 1:12, to test the hypothesis that ratio adherence is associated with lower inpatient mortality.

MATERIALS AND METHODS

The registry of an urban level I trauma center was queried for adult patients who received at least 6 units of packed red blood cells within 4 hours of presentation. Patients were excluded for interfacility transfer, cardiac arrest during the prehospital phase or within one hour of arrival, or for head AIS ≥5. Univariate analysis and multiple logistic regressions were performed to identify variables associated with early transfusion protocol noncompliance and the effect on inpatient mortality.

RESULTS

Three hundred and eighty-three patients were included, with mean ISS of 25.9 ± 13.3 and inpatient mortality of 28.5%. Increasing age, ISS, INR, and total units of blood product transfused were associated with increased odds of mortality, while an increase in revised trauma score was associated with a decreased odds ratio of mortality. Achieving our goal ratios were protective against mortality, with OR of .451 (P = .013) and .402 (P=.003), respectively.

DISCUSSION

Large proportions of critically injured patients were transfused fewer units of plasma and platelets than our MTP dictated; failure to achieve intended ratios at 4 hours was strongly associated with inpatient mortality. MTP processes and outcomes should be critically assessed on a regular basis as part of a mature performance improvement program to ensure protocol adherence and optimal patient outcome.

Preventable deaths in hospitalized trauma patients

AIM

To study the preventable trauma deaths of hospitalized patients in the United Arab Emirates and to identify opportunities for improvement.

METHODS

We analyzed the Abu Dhabi Emirate Trauma Registry data of admitted patients who died in the emergency department or in hospital from 2014 to 2019. A panel of experts categorize the deaths into not preventable (NP), potentially preventable (PP), and definitely preventable (DP).

RESULTS

A total of 405 deaths were included, and 82.7% were males. The majority (89.1%) were NP, occurring mainly in the emergency department (40.4%) and the intensive care unit (49.9%). The combined potentially preventable and preventable death rate was 10.9%. The median (Interquartile range) age of the DP was 57.5 (37-76) years, compared with 32 (24-42) and 34 (25-55) years for NP and PP, respectively (p = 0.008). Most of the PP deaths occurred in the intensive care unit (55.6%), while the DP occurred mainly in the ward (50%). Falls accounted for 25% of PP and DP. Deficiencies in airway care, hemorrhage control, and fluid management were identified in 25%, 43.2% and 29.5% of the DP/PP deaths, respectively. Seventy-two percent of the Airway deficiencies occurred in the prehospital, while 34.1% of hemorrhage control deficiencies were in the emergency department. Fluid management deficiencies occurred in the emergency department and the operation theater.

CONCLUSIONS

DP and PP deaths comprised 10.9% of the deaths. Most of the DP occurred in the emergency department and ward. Prehospital Airway and in-hospital hemorrhage and excessive fluid were the main areas for opportunities for improvement.

Stop the Bleed in the Era of Virtual Learning: A Novel Strategy for Remote Teaching and Evaluation

INTRODUCTION

Traumatic hemorrhage is a leading cause of preventable mortality worldwide. The Stop the Bleed (STB) course was developed to equip layperson bystanders with basic bleeding control knowledge and skills. However, large in-person courses have been disrupted due to COVID-19. The aim of this study was to determine the feasibility of teaching and evaluating STB skills through remote video-based instruction.

METHODS

After undergoing COVID-19 screening, groups of up to eight STB-naive adults were seated in a socially distanced manner and given individual practice kits. A remote STB-certified instructor provided the standard STB lecture and led a 10-min skills practice session via videoconferencing. Participants' skills were evaluated on a 10-point rubric by one in-person evaluator and three remote evaluators. Participants completed a postcourse survey assessing their perceptions of the course.

RESULTS

Thirty-five participants completed the course, all scoring ≥8/10 after examination by the in-person evaluator. Remote instructors' average scores (9.8 ± 0.45) did not significantly differ from scores of the in-person evaluator (9.9 ± 0.37) (P = 0.252). Thirty-three participants (94%) completed the postcourse survey. All respondents reported being willing and prepared to intervene in scenarios of life-threatening hemorrhage, and 97% reported confidence in using all STB skills.

CONCLUSIONS

STB skills can be effectively taught and evaluated through a live video-based course. All participants scored highly when evaluated both in-person and remotely, and nearly all reported confidence in skills and knowledge following the course. Remote instruction is a valuable strategy to disseminate STB training to students without access to in-person courses, especially during pandemic restrictions.

Doing more with less: low-titer group O whole blood resulted in less total transfusions and an independent association with survival in adults with severe traumatic hemorrhage

BACKGROUND

Low-titer group O whole blood (LTOWB) or component therapy (CT) may be used to resuscitate hemorrhaging trauma patients. LTOWB may have clinical and logistical benefits and may improve survival.

OBJECTIVES

We hypothesized LTOWB would improve 24-hour survival in hemorrhaging patients and would be safe and equally efficacious in non-group O compared with group O patients.

METHODS

Adult trauma patients with massive transfusion protocol activations were enrolled in this observational study. The primary outcome was 24-hour mortality. Secondary outcomes included 72-hour total blood product use. A Cox regression determined the independent associations with 24-hour mortality.

RESULTS

In total, 348 patients were included (CT, n = 180; LTOWB, n = 168). Demographics were similar between cohorts. Unadjusted 24-hour mortality was reduced in LTOWB vs CT: 8% vs 19% (P = .003), but 6-hour and 28-day mortality were similar. In an adjusted analysis with multivariable Cox regression, LTOWB was independently associated with reduced 24-hour mortality (hazard ratio, 0.21; 95% CI, 0.07-0.67; P = .004). LTOWB patients received significantly less 72-hour total blood products (80.9 [41.6-139.3] mL/kg vs 48.9 [25.9-106.9] mL/kg; P < .001). In stratified 24-hour survival analyses, LTOWB was associated with improved survival for patients in shock or with coagulopathy. LTOWB use in non-group O patients was not associated with increased mortality, organ injury, or adverse events.

CONCLUSION

In this hypothesis-generating study, LTOWB use was independently associated with improved 24-hour survival, predominantly in patients with shock or coagulopathy. LTOWB also resulted in a 40% reduction in blood product use which equates to a median 2.4 L reduction in transfused products.

Trojan-horse mineralization of trigger factor to impregnate non-woven alginate fabrics for enhanced hemostatic efficacy

Uncontrolled hemorrhage remains a leading cause of mortality after trauma. This work describes a facile mineralization strategy for enhancing hemostatic efficacy of alginate non-woven fabrics, involving the precipitation of amorphous CaCO3 induced by alginate fibers, along with Trojan-horse-like tissue factor (TF) encapsulation. The amorphous CaCO3 served as a transient carrier, capable of releasing Ca2+ and TF upon contact with blood. Coagulation test and rat tail cut and hemorrhaging liver models all revealed superior hemostatic capability of mineralized TF-in-alginate fabrics compared to bare fabrics, solely mineralized form, or commercial zeolite-modified gauze, benefiting from the combined hemostatic properties of alginate matrix and released Ca2+ and TF. Meanwhile, comprehensive biocompatibility and mechanical stability evaluations demonstrate the ternary composite's good biosafety. These results along with the extension study with chitosan- and cellulose-based dressings underline the great potential and versatility of polysaccharide-hemostat-mediated CaCO3 mineralization with TF integration for achieving rapid hemorrhage control.

TCCC Decision Support With Machine Learning Prediction of Hemorrhage Risk, Shock Probability

INTRODUCTION

Expected future delays in evacuation during near-peer conflicts in remote locales are expected to require extended care including prolonged field care over hours to days. Such delays can increase potential complications, such as insufficient blood flow (shock), bloodstream infection (sepsis), internal bleeding (hemorrhage), and require more complex treatment beyond stabilization. The Trauma Triage Treatment and Training Decision Support (4TDS) system is a real-time decision support system to monitor casualty health and identify such complications. The 4TDS software prototype operates on an Android smart phone or tablet configured for use in the DoD Nett Warrior program. It includes machine learning models to evaluate trends in six vital signs streamed from a sensor placed on a casualty to identify shock probability, internal hemorrhage risk, and need for a massive transfusion.

MATERIALS AND METHODS

The project team used a mixed methods approach to create and evaluate the system including literature review, rapid prototyping, design requirements review, agile development, an algorithm "silent test," and usability assessments with novice to expert medics from all three services.

RESULTS

Both models, shock (showing an accuracy of 0.83) and hemorrhage/massive transfusion protocol, were successfully validated using externally collected data. All usability assessment participants completed refresher training scenarios and were able to accurately assess a simulated casualty's condition using the phone prototype. Mean responses to statements on evaluation criteria [e.g., fit with Tactical Combat Casualty Care (TCCC), ease of use, and decision confidence] fell at five or above on a 7-point scale, indicating strong support.

CONCLUSIONS

Participatory design ensured 4TDS and machine learning models reflect medic and clinician mental models and work processes and built support among potential users should the system transition to operational use. Validation results can support 4TDS readiness for FDA 510k clearance as a Class II medical device.

Tracking Research on Hemoglobin-Based Oxygen Carriers: A Scientometric Analysis and In-Depth Review

Numerous studies on the formulation and clinical applications of novel hemoglobin-based oxygen carriers (HBOCs) are reported in the scientific literature. However, there are fewer scientometric analysis related to HBOCs. Here, we illustrate recent studies on HBOCs using both a scientometric analysis approach and a scope review method. We used the former to investigate research on HBOCs from 1991 to 2022, exploring the current hotspots and research trends, and then we comprehensively analyzed the relationship between concepts based on the keyword analysis. The evolution of research fields, knowledge structures, and research topics in which HBOCs located are revealed by scientometric analysis. The elucidation of type, acting mechanism, potential clinical practice, and adverse effects of HBOCs helps to clarify the prospects of this biological agent. Scientometrics analyzed 1034 publications in this research field, and these findings provide a promising roadmap for further study.

A polymer-based systemic hemostat for managing uncontrolled bleeding

Uncontrolled bleeding is a life-threatening emergency that requires immediate intervention. Currently available on-site bleeding interventions largely rely on the use of tourniquets, pressure dressing, and other topical hemostatic agents, which can only treat bleeding injuries that are known, accessible, and potentially compressible. Synthetic hemostats that are stable at room temperature, easy to carry, field-usable, and able to stop internal bleeding at multiple or unknown sources, are still lacking. We recently developed a hemostatic agent via polymer peptide interfusion (HAPPI), which can selectively bind to activated platelets and injury sites after intravascular administration. Here we report that HAPPI is highly effective in treating multiple lethal traumatic bleeding conditions in normal as well as hemophilia models via either systemic administration or topical application. In a rat liver traumatic model, intravenous injection of HAPPI resulted in a significant decrease in blood loss and a four-fold reduction in mortality rate within 2 h after injury. When applied topically on liver punch biopsy wounds in heparinized rats, HAPPI achieved a 73% of reduction in blood loss and a five-fold increase in survival rate. HAPPI also exhibited hemostatic efficacy in hemophilia A mice by reducing blood loss. Further, HAPPI worked synergistically with rFVIIa to induce immediate hemostasis and 95% reduction in total blood loss compared to the saline-treated group in hemophelia mice models. These results demonstrate that HAPPI is a promising field-usable hemostatic agent for a broad range of different hemorrhagic conditions.

A Super Tough, Rapidly Biodegradable, Ultrafast Hemostatic Bioglue

Death happening due to massive hemorrhage has been involved in military conflicts, traffic accidents, and surgical injuries of various human disasters. Achieving rapid and effective hemostasis to save lives is crucial in urgent massive bleeding situations. Herein, a covalent cross-linked AG-PEG glue based on extracellular matrix-like amino-gelatin (AG) and PEG derivatives is developed. The AG-PEG glue gelatinizes fast and exhibits firm and indiscriminate close adhesion with various moist tissues upon being dosed. The formed glue establishes an adhesive and robust barrier to seal the arterial, hepatic, and cardiac hemorrhagic wounds, enabling it to withstand up to 380 mmHg blood pressure in comparison with normal systolic blood pressure of 60-180 mmHg. Remarkably, massive bleeding from a pig cardiac penetrating hole with 6 mm diameter is effectively stopped using the glue within 60 s. Postoperative indexes of the treated pig gradually recover and the cardiac wounds regrow significantly at 14 days. Possessing on-demand solubility, self-gelling, and rapid degradability, the AG-PEG glue may provide a fascinating stop-bleeding approach for clinical hemostasis and emergency rescue.

Supramolecularly functionalized platelets for rapid control of hemorrhage

Excessive bleeding has always been of great medical challenge, particularly in trauma and surgery. Due to the fast clearance of medicine and complex hemodynamics during hemorrhage, it is often difficult to achieve rapid and effective hemostasis on irregularly shaped, noncompressible visceral bleeding wounds. Herein, we report a hemostatic derived from supramolecularly functionalized platelets (SPLTs), showing rapid hemorrhage controlling effects via efficiently targeting injured vessels and in-situ aggregation. Von Willebrand factor-binding peptide (VBP) modified hyaluronic acid (HA-VBP) decorated platelets (PLTs) were fabricated via supramolecular host-guest interactions between cucurbit[7]uril (CB[7], a host molecule) modified on HA-VBP (HA-CB[7]-VBP) and adamantane (ADA, a guest molecule) anchored on the surface of PLTs (ADA-PLTs). The SPLTs demonstrated approximately 10-fold improvements than the native PLTs in the targeting efficiency into the injured vessels in mice upon intravenous injection. More significantly, the total bleeding time and bleeding volume were dramatically reduced down to less than 1/4 and 1/10 of the control group, respectively, in both external and internal major bleeding mice models. This SPLTs provide a facile yet effective approach for rapid control of major hemorrhage and offers important new insights to the design and development PLTs-based hemostatics. STATEMENT OF SIGNIFICANCE: Hemorrhage is one of the greatest threats to humans in trauma and surgery. To reduce bleeding volume and time, transfusion of hematological products such as platelets (PLTs)-rich plasma is one of the most commonly used therapeutics, but with low targeting and hemostatic efficiency. Thus, engineered PLTs with expanded structural repertoire and functionalities are in urgent clinical needs. Herein, we developed supramolecularly functionalized PLTs (SPLTs), prepared with a mild and facile approach, for rapid control of hemorrhage with significantly enhanced targeting efficiency. The SPLTs not only provide a facile approach for rapid control of major hemorrhage, but also offer important new insights into the development PLTs-based hemostatics.

Percutaneous delivery of self-propelling thrombin-containing powder increases survival from non-compressible truncal hemorrhage in a swine model of coagulopathy and hypothermia

BACKGROUND

Non-compressible truncal hemorrhage (NCTH) remains a leading cause of preventable death on the battlefield. Definitively managing severe NCTH requires surgery within the first hour after injury, which is difficult when evacuating casualties from remote and austere environments. During delays to surgery, hemostatic interventions that are performed prehospital can prevent coagulopathy and hemorrhagic shock and increase the likelihood that casualties survive to receive definitive care. We previously reported that a self-propelling thrombin-containing powder (SPTP) can be delivered percutaneously into the abdomen as a minimally invasive intervention and can self-disperse through pooled blood to deliver the hemostatic agents thrombin and tranexamic acid (TXA) locally to noncompressible intracavitary wounds. We hypothesized that in swine with massive NCTH, dilutional coagulopathy and hypothermia, delivering SPTP could extend survival times.

METHODS

Ten swine (n = 5 per group) underwent NCTH from a Grade V liver injury following a midline laparotomy. The laparotomy was closed with sutures afterwards, creating a hemoperitoneum, and animals were managed with crystalloid fluid resuscitation, or crystalloid resuscitation and SPTP. SPTP was delivered into the closed abdomen using a CO2-powered spray device and a catheter placed into the hemoperitoneum, entering through the upper right quadrant using the Seldinger technique. Survival to one and three hours was recorded. In an additional animal, hemorrhage was created laparoscopically and SPTP was imaged in-situ within the abdomen to visually track dispersion of the particles.

RESULTS

SPTP dispersed as far as 35 +/- 5.0 cm within the abdomen. SPTP increased survival to one and three hours (Kaplan-Meier p = 0.007 for both). The median survival time was 61 minutes with SPTP and 31 minutes without (p = 0.016).

CONCLUSION

SPTP effectively disperses medications throughout a hemoperitoneum and increases survival in a model of NCTH. SPTP is a promising strategy for nonsurgical management of NCTH, warranting further testing of its safety and efficacy.

LEVEL OF EVIDENCE

Basic Science, N/A.

Percutaneous delivery of self-propelling hemostatic powder for managing non-compressible abdominal hemorrhage: a proof-of-concept study in swine

INTRODUCTION

Non-compressible intra-abdominal hemorrhage (NCIAH) is a major cause of preventable death on the battlefield and in civilian trauma. Currently, it can only be definitively managed with surgery, as there are limited strategies for controlling ongoing NCIAH in the prehospital environment. We hypothesized that a self-propelling thrombin-containing powder (SPTP) could increase survival in a swine model of NCIAH when delivered percutaneously into the closed abdomen using an engineered spray system.

MATERIALS AND METHODS

Nineteen swine underwent surgical laparotomy followed by a Grade V liver injury that created massive hemorrhage, before closing the abdomen with sutures. Animals either received treatment with standard of care fluid resuscitation (n=9) or the SPTP spray system (n=10), which consisted of a spray device and a 14 Fr catheter. Using the spray system, SPTP was delivered into a hemoperitoneum identified using a focused assessment with sonography in trauma (FAST) exam. Lactated Ringer's solution was administered to all animals to maintain a mean arterial pressure (MAP) of >50 mmHg. The primary outcome was percentage of animals surviving at three hours following injury.

RESULTS

In the swine model of NCIAH, a greater percentage of animals receiving SPTP survived to three hours, although differences were not significant. The SPTP spray system increased the median survival of animals from 1.6 hr in the fluid resuscitation group to 4.3 hr. The SPTP spray system delivered a total mass of 18.5 ± 1.0 g of SPTP. The mean change in intra-abdominal pressure following SPTP delivery was 5.2 ± 1.8 mmHg (mean ± SEM). The intervention time was 6.7 ± 1.7 min. No adverse effects related to the SPTP formulation or the spray system were observed. SPTP was especially beneficial in animals that had either severely elevated lactate concentrations or low mean arterial pressure of <35 mmHg shortly after injury.

CONCLUSIONS

This demonstrates proof-of-concept for use of a new minimally invasive procedure for managing NCIAH, which could extend survival time to enable patients to reach definitive surgical care.

Ascorbic Acid as an Adjuvant to Unbleached Cotton Promotes Antimicrobial Activity in Spunlace Nonwovens

The development of affordable, effective, and environmentally friendly barrier fabrics is a current goal in antimicrobial textile development. The discovery of new routes to achieve non-toxic naturally occurring molecules with antimicrobial activity is of interest in the development of materials that promote wound healing, improve hygiene, and offer protection against nosocomial infection. Highly cleaned and sterile unbleached cotton has constituents that produce hydrogen peroxide at levels commensurate with those that favor cell signaling in wound healing. Here, we show the antimicrobial and antiviral properties of spunlaced griege cotton-containing nonwovens treated with ascorbic acid formulations. The mechanism of action occurs through the promotion of enhanced hydrogen peroxide activity. The levels of hydrogen peroxide activity afford antimicrobial activity against Gram-negative and Gram-positive bacteria and antiviral activity against MS2 bacteriophages. Spun-bond nonwoven unbleached cotton was treated with ascorbic acid using traditional pad-dry-cure methods. An assessment of antibacterial and antiviral activity against Staphylococcus aureus, Klebsiella pneumoniae, and MS2 bacteriophages with the AATCC 100 test method showed a 99.99% inhibitory activity. An approach to the covalent attachment of ascorbic to cellulose through citric acid crosslinking chemistry is also discussed. Thus, a simple, low-cost approach to antimicrobial and antiviral cotton-based nonwovens applicable to dressings, nosocomial barrier fabrics, and face masks can be adopted by combining ascorbic acid with spunlace greige cotton nonwoven fabrics.

Developing a National Trauma Research Action Plan (NTRAP): Results from the Pediatric Research Gap Delphi Survey

BACKGROUND

In 2016, the National Academies of Sciences, Engineering, and Medicine trauma report recommended a National Trauma Research Action Plan (NTRAP) to "strengthen trauma research and ensure that the resources available for this research are commensurate with the importance of injury and the potential for improvement in patient outcomes." With a contract from the Department of Defense, the Coalition for National Trauma Research (CNTR) created 11 expert panels to address this recommendation, with the goal of developing a comprehensive research agenda, spanning the continuum of trauma and burn care. This report outlines the work of the group focused on pediatric trauma.

METHODS

Experts in pediatric trauma clinical care and research were recruited to identify gaps in current clinical pediatric trauma research, generate research questions, and establish the priority of these questions using a consensus-driven Delphi survey approach. Using successive surveys, participants were asked to rank the priority of each research question on a 9-point Likert scale categorized to represent priority. Consensus was defined as >60% agreement within the priority category. Priority questions were coded based on a dictionary of 118 NTRAP taxonomy concepts in nine categories to support comparative analysis across all panels.

RESULTS

37 subject matter experts generated 625 questions. 493 questions (79%) reached consensus on priority level. Of those reaching consensus, 159 (32%) were High, 325 (66%) Medium and 9 (2%) Low priority. The highest priority research questions related to surgical interventions for traumatic brain injury (ICP monitoring and craniotomy); second highest priority was hemorrhagic shock. The prehospital setting was the highest priority phase of care.

CONCLUSIONS

This diverse panel of experts determined that most significant pediatric trauma research gaps were in traumatic brain injur, hemorrhagic shock, and the prehospital phase of care. These research domains should be top priorities for funding agencies.

LEVEL OF EVIDENCE

IV.

Emerging gene therapies for enhancing the hemostatic potential of platelets

Platelet transfusions are an integral component of balanced hemostatic resuscitation protocols used to manage severe hemorrhage following trauma. Enhancing the hemostatic potential of platelets could lead to further increases in the efficacy of transfusions, particularly for non-compressible torso hemorrhage or severe hemorrhage with coagulopathy, by decreasing blood loss and improving overall patient outcomes. Advances in gene therapies, including RNA therapies, are leading to new strategies to enhance platelets for better control of hemorrhage. This review will highlight three approaches for creating modified platelets using gene therapies: (i) direct transfection of transfusable platelets ex vivo, (ii) in vitro production of engineered platelets from platelet-precursor cells, and (iii) modifying the bone marrow for in vivo production of modified platelets. In summary, modifying platelets to enhance their hemostatic potential is an exciting new frontier in transfusion medicine, but more preclinical development as well as studies testing the safety and efficacy of these agents are needed.

Spray-dried plasma: A post-traumatic blood "bridge" for life-saving resuscitation

Massive bleeding remains a major source of morbidity and mortality worldwide. Recent studies have shed light on the pathophysiology of traumatic-induced coagulopathy and the central role of endotheliopathy. Transfusion therapy has changed dramatically in the last decade with use of red cells and plasma in a 1:1 ratio. The use of early transfusion increases the likelihood of a favorable outcome. Early intervention-preferably less than 60 min of injury-is a major factor in improved survival. Experience with dried plasma products-lyophilized or freeze-dried-in Europe and South Africa has demonstrated both safety and efficacy. Dry plasma products are not available in the United States but several products are in development. Spray-dried plasma contains clinically meaningful levels of coagulation activity and in vitro data suggest robust ability to generate thrombus. The decentralized, blood-center based manufacturing model of spray-dried plasma offers advantages for availability to meet routine and extraordinary demands.

Antimicrobial and Hemostatic Activities of Cotton-Based Dressings Designed to Address Prolonged Field Care Applications

INTRODUCTION

Developing affordable and effective hemostatic and antimicrobial wound dressings for prolonged field care (PFC) of open wounds is of interest to prevent infection, to prevent sepsis, and to conserve tissue viability. The need for an effective hemostatic dressing that is also antimicrobial is required of a hemostatic dressing that can be left in place for extended periods (days). This is particularly important in light of the existence of pathogens that have coagulopathy properties. Thus, dressings that provide effective hemostasis and reduction in the frequency of dressing changes, whereas exerting robust antimicrobial activity are of interest for PFC. Highly cleaned and sterile unbleached cotton has constituents not found in bleached cotton that are beneficial to the hemostatic and inflammatory stages of wound healing. Here, we demonstrate two approaches to cotton-based antimicrobial dressings that utilize the unique components of the cotton fiber with simple modification to confer a high degree of hemostatic and antimicrobial efficacy.

METHODS

Spun bond nonwoven unbleached cotton was treated using traditional pad dry cure methods to add ascorbic acid, zeolite (NaY) with pectin, calcium chloride, and sodium carbonate/calcium chloride. Similarly, nanosilver-embedded cotton fiber was blended with pristine cotton fibers at various weight ratios to produce hydroentangled nonwoven fabrics. The resulting treated fabrics were assessed for hemostasis using thromboelastographic clotting assays and antimicrobial activity utilizing American Association of Textile Chemists and Colorists 100.

RESULTS

Zeolite-containing dressings possessed significant hemostatic activity, whereas ascorbic acid- and silver-containing dressings reduced Gram-positive and Gram-negative organism numbers by several logs.

CONCLUSION

Based on this study, a multilayered hemostatic dressing with antimicrobial properties is envisioned. This dressing would be safe, would be economical, and have a stable shelf-life that would be conducive for using PFC.

Improved Hemodynamic Recovery and 72-Hour Survival Following Low-Volume Resuscitation with a PEGylated Carboxyhemoglobin in a Rat Model of Severe Hemorrhagic Shock

INTRODUCTION

Hemorrhage is a leading cause of death from potentially survivable civilian and military trauma. As projected conflicts move from settings of tactical and logistical supremacy to hyper-dynamic tactical zones against peer and near-peer adversaries, protracted medical evacuation times are expected. Treatment at the point-of-injury is critical. Although crystalloids like Lactated Ringer's (LR) are ubiquitous, whole blood (WB) is the preferred resuscitation fluid following hemorrhage; however, logistical constraints limit the availability of WB in prehospital settings. Hemoglobin-based oxygen carriers (HBOCs) offer both hemodynamic support and oxygen-carrying capacity while avoiding logistical constraints of WB. We hypothesized that low-volume resuscitation of severe hemorrhagic shock with an HBOC (PEGylated carboxyhemoglobin, [PC]) would improve hemodynamic recovery and 72-hour survival; comparable to WB and superior to LR.

MATERIALS AND METHODS

A total of 21 anesthetized male Sprague-Dawley rats underwent severe hemorrhagic shock followed by randomly assigned low-volume resuscitation with LR, WB, or PC, and then recovered from anesthesia for up to 72-hour observation. Mean arterial pressure (MAP) was recorded continuously under anesthesia, and arterial blood gases were measured at baseline (BL), 60 minutes post-hemorrhage (HS1h), and 24 hours post-resuscitation (PR24h). Survival was presented on a Kaplan-Meier plot and significance determined with a log-rank test. Cardiovascular and blood gas data were assessed with one-way analysis of variance and post hoc analysis where appropriate.

RESULTS

All measured cardiovascular and blood chemistry parameters were equivalent between groups at BL and HS1h. BL MAP values were 90 ± 3, 86 ± 1, and 89 ± 2 mmHg for LR, PC, and WB, respectively. Immediately following resuscitation, MAP values were 57 ± 4, 74 ± 5, and 62 ± 3 mmHg, with PC equivalent to WB and higher than LR (P < 0.05). WB and LR were both lower than BL (P < 0.0001), whereas PC was not (P = 0.13). The PC group's survival to 72 hours was 57%, which was not different from WB (43%) and higher than LR (14%; P < 0.05).

CONCLUSIONS

A single bolus infusion of PC produced superior survival and MAP response compared to LR, which is the standard fluid resuscitant carried by combat medics. PC was not different from WB in terms of survival and MAP, which is encouraging because its reduced logistical constraints make it viable for field deployment. These promising findings warrant further development and investigation of PC as a low-volume, early treatment for hemorrhagic shock in scenarios where blood products may not be available.

The clock is ticking: using in situ simulation to improve time to blood administration for bleeding trauma patients

INTRODUCTION

Massive hemorrhage protocols are widely used to facilitate the administration of blood components to bleeding trauma patients. Delays in this process are associated with worse patient outcomes. We used in situ simulation as a novel and iterative quality improvement technique to reduce the mean time between massive hemorrhage protocol activation and blood administration during actual trauma resuscitations.

METHODS

We completed monthly, risk-informed unannounced in situ trauma simulations at a Canadian Level 1 trauma centre. We identified three major latent safety threats: (1) massive hemorrhage protocol activation; (2) transport of blood components; and (3) situational awareness of team members. Process improvements for each latent safety threats were tested and implemented during subsequent in situ simulation sessions. We evaluated the effect of this simulation-based intervention on the care of patients before, during and after the intervention. Demographic, clinical and massive hemorrhage protocol data were collected. The primary outcome was mean time between massive hemorrhage protocol activation and blood administration during actual trauma resuscitations as analyzed using a two-sample t test.

RESULTS

Each group was similar in demographic and injury characteristics. The time from massive hemorrhage protocol activation to blood administration decreased from 11.6 min pre-intervention to 9.1 min post-intervention. This represented a significant reduction (2.5 min, 95% confidence interval, 0.03-5.08) following the in situ simulation-based quality improvement intervention.

CONCLUSIONS

A comprehensive, in situ simulation-based quality improvement project was associated with a significant reduction in the mean time between massive hemorrhage protocol activation and blood administration among injured patients. In situ simulation represents a novel approach to the identification and mitigation of latent safety threats during massive hemorrhage protocol activation.

Whole Blood, Fixed Ratio, or Goal-Directed Blood Component Therapy for the Initial Resuscitation of Severely Hemorrhaging Trauma Patients: A Narrative Review

This narrative review explores the pathophysiology, geographic variation, and historical developments underlying the selection of fixed ratio versus whole blood resuscitation for hemorrhaging trauma patients. We also detail a physiologically driven and goal-directed alternative to fixed ratio and whole blood, whereby viscoelastic testing guides the administration of blood components and factor concentrates to the severely bleeding trauma patient. The major studies of each resuscitation method are highlighted, and upcoming comparative trials are detailed.

First Aid Practices for Injured Children in Rural Ghana: A Cluster-Random Population-Based Survey

INTRODUCTION

The majority of injury deaths occur outside health facilities. However, many low- and middle-income countries (LMICs) continue to lack efficient Emergency Medical Services (EMS). Understanding current first aid practices and perceptions among members of the community is vital to strengthening non-EMS, community-based prehospital care.

STUDY OBJECTIVE

This study sought to determine caregiver first aid practices and care-seeking behavior for common household child injuries in rural communities in Ghana to inform context-specific interventions to improve prehospital care in LMICs.

METHODS

A cluster-randomized, population-based household survey of caregivers of children under five years in a rural sub-district (Amakom) in Ghana was conducted. Caregivers were asked about their practices and care-seeking behaviors should children sustain injuries at home. Common injuries of interest were burns, laceration, choking, and fractures. Multiple responses were permitted and reported practices were categorized as: recommended, low-risk, or potentially harmful to the child. Logistic regression was used to examine the association between caregiver characteristics and first aid practices.

RESULTS

Three hundred and fifty-seven individuals were sampled, representing 5,634 caregivers in Amakom. Mean age was 33 years. Most (79%) were mothers to the children; 68% had only completed basic education. Most caregivers (64%-99%) would employ recommended first aid practices to manage common injuries, such as running cool water over a burn injury or tying a bleeding laceration with a piece of cloth. Nonetheless, seven percent to 56% would also employ practices which were potentially harmful to the child, such as attempting manual removal of a choking object or treating fractures at home without taking the child to a health facility. Reporting only recommended practices ranged from zero percent (burns) to 93% (choking). Reporting only potentially harmful practices ranged from zero percent (burns) to 20% (fractures). Univariate regression analysis did not reveal consistent associations between various caregiver characteristics and the employment of recommended only or potentially harmful only first aid practices.

CONCLUSIONS

Caregivers in rural Ghanaian communities reported using some recommended first aid practices for common household injuries in children. However, they also employed many potentially harmful practices. This study highlights the need to increase context-appropriate, community-targeted first aid training programs for rural community populations of LMICs. This is important as the home-based care provided for injured children in these communities might be the only care they receive.

Tranexamic Acid Use in Pediatric Hemorrhagic Shock From Farm-Related Trauma: A Case Report

This case describes the use of tranexamic acid as an adjunctive treatment in the management of a pediatric patient in hemorrhagic shock. The case also highlights other components of current best practices for hemorrhagic shock in children, including bleeding source control and prompt resuscitation with blood products. A 20-month old male suffered an agricultural accident with significant injury to the right upper extremity. This led to subsequent extremity hemorrhage and clinical evidence of hemorrhagic shock. As a result of interventions performed by emergency medical services as well as the helicopter emergency medical services team, including the application of a tourniquet, prehospital blood product administration, and tranexamic acid administration, the patient had hemodynamically stabilized by arrival at the level 1 pediatric trauma center and was neurologically intact when discharged from the hospital.

A polymer-based systemic hemostatic agent

Uncontrolled noncompressible hemorrhage is a major cause of mortality following traumatic injuries in civilian and military populations. An injectable hemostat for point-of-care treatment of noncompressible hemorrhage represents an urgent medical need. Here, we describe an injectable hemostatic agent via polymer peptide interfusion (HAPPI), a hyaluronic acid conjugate with a collagen-binding peptide and a von Willebrand factor-binding peptide. HAPPI exhibited selective binding to activated platelets and promoted their accumulation at the wound site in vitro. In vivo studies in mouse tail vein laceration model demonstrated a reduction of >97% in both bleeding time and blood loss. A 284% improvement in the survival time was observed in the rat inferior vena cava traumatic model. Lyophilized HAPPI could be stably stored at room temperature for several months and reconstituted during therapeutic intervention. HAPPI provides a potentially clinically translatable intravenous hemostat.

The use of low-titer group O whole blood is independently associated with improved survival compared to component therapy in adults with severe traumatic hemorrhage

BACKGROUND

There is a resurgence in the use of low-titer group O whole blood (LTOWB) for hemorrhagic shock. We hypothesized the use of LTOWB compared to component therapy (CT) would be independently associated with improved 24-hour mortality.

STUDY DESIGN AND METHODS

In this prospective observational study, trauma patients 18 years of age or older with massive transfusion protocol activations were included from August 17, 2018, to May 14, 2019. The primary outcome was 24-hour mortality. Secondary outcomes included 72-hour blood product totals, multiple organ dysfunction scores (MODS), and 28-day mortality. Multivariable logistic regression (MVLR) and Cox regression were performed to determine independent associations.

RESULTS

There were no clinically meaningful differences in measures of injury severity between study groups (CT, n = 42; LTOWB, n = 44). There was no difference in MODS between study groups. The unadjusted mortality was not statistically different between the study groups (9/42 [21%] for CT vs. 7/44 [16%] for LTOWB; p = 0.518). In the MVLR model, LTOWB increased the odds of 24-hour survival by 23% (odds ratio 0.81, 95% confidence interval 0.69-0.96; p = 0.017). Adjusted survival curve analysis indicated improved survival at both 24 hours and 28 days for LTOWB patients (p < 0.001). Further stratification showed an association between LTOWB use and survival when maximum clot firmness (MCF) was 60 mm or less (p = 0.009).

CONCLUSIONS

The use of LTOWB is independently associated with improved 24-hour and 28-day survival, and does not increase organ dysfunction at 72 hours. Use of LTOWB most impacted survival of patients with reduced clot firmness (MCF ≤60 mm). Collectively, these data support the clinical use and continued study of LTOWB for hemostatic resuscitation.

Intraoperative REBOA: an analysis of the American Association for the Surgery of Trauma AORTA registry

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a less-invasive technique for aortic occlusion (AO). Commonly performed in the emergency department (ED), the role of intraoperative placement is less defined. We hypothesized that operating room (OR) placement is associated with increased in-hospital mortality.

Methods

The American Association for the Surgery of Trauma AORTA registry was used to identify patients undergoing REBOA. Injury characteristics and outcomes data were compared between OR and ED groups. The primary outcome was in-hospital mortality; secondary outcomes included total AO time, transfusion requirements, and acute kidney injury.

Results

Location and timing of catheter insertion were available for 305 of 321 (95%) subjects. 58 patients underwent REBOA in the OR (19%). There were no differences with respect to sex, admission lactate, and Injury Severity Score. The OR group was younger (33 years vs. 41 years, p=0.01) and with more penetrating injuries (36% vs. 15%, p<0.001). There were significant differences with respect to admission physiology. Time from admission to AO was longer in the OR group (75 minutes vs. 23 minutes, p<0.001) as was time to definitive hemostasis (116 minutes vs. 79 minutes, p=0.01). Unadjusted mortality was lower in the OR group (36.2% vs. 68.8%, p<0.001). There were no differences in secondary outcomes. After controlling for covariates, there was no association between insertion location and in-hospital mortality (OR 1.8, 95% CI 0.30 to 11.50).

Discussion

OR REBOA placement is common and generally employed in patients with more stable admission physiology. OR placement was not associated with increased in-hospital mortality despite longer times to AO and definite hemostasis when compared with catheters placed in the ED.

Level of evidence

IV; therapeutic/care management.

Effect of leukoreduction and pathogen reduction on the hemostatic function of whole blood

BACKGROUND

There is renewed interest in the use of whole blood (WB) for resuscitation of patients in hemorrhagic shock. Leukoreduction with platelet-sparing filters and pathogen reduction may be used to improve the safety profile of WB, yet the effects of leukoreduction and pathogen reduction on WB hemostatic function are not well characterized.

STUDY DESIGN AND METHODS

Blood from 32 healthy group O donors was divided into treatment groups (n = 8 for each group): untreated, pathogen reduced (PR⁺ ), leukoreduced using an in-line filter (LR⁺ ), or PR⁺ LR⁺ . Units were stored without agitation for 21 days between 1° and 6°C, with sampling on days 0 (pre- and post-treatments), 1, 3, 5, 10, 15, and 21 for hemostatic function as assessed by thromboelastometry, thrombin generation, platelet activation factors, and platelet impedance aggregometry.

RESULTS

From day 3 (D3) to D15 of storage, platelet count was reduced in PR⁺ /LR⁺ units compared to PR^- /LR^- units. From D10 to D21 of storage, maximum clot firmness (MCF) was reduced in PR⁺ /LR⁺ units compared to PR^- /LR^- units. From D3 to D21 of storage, platelet aggregation was reduced in PR⁺ /LR⁺ units compared to PR^- /LR^- units. Total thrombin generation was similar in all groups from D0 to D21.

CONCLUSIONS

The combination of LR with a platelet-sparing filter and PR significantly reduces hemostatic function compared to either treatment alone or untreated WB. The clinical consequences of LR and PR of WB in patients with severe bleeding should be examined in trials before both are used in combination in patients.

A regional massive hemorrhage protocol developed through a modified Delphi technique

BACKGROUND

A massive hemorrhage protocol (MHP) enables rapid delivery of blood components in a patient who is exsanguinating pending definitive hemorrhage control, but there is variability in MHP implementation rates, content and compliance owing to challenges presented by infrequent activation, variable team performance and patient acuity. The goal of this project was to identify the key evidence-based principles and quality indicators required to develop a standardized regional MHP.

METHODS

A modified Delphi consensus technique was performed in the spring and summer of 2018. Panellists used survey links to independently review and rate (on a 7-point Likert scale) 43 statements and 8 quality indicators drafted by a steering committee composed of transfusion medicine specialists and technologists, and trauma physicians. External stakeholder input from all hospitals in Ontario was sought.

RESULTS

Three rounds were held with 36 experts from diverse clinical backgrounds. Consensus was reached for 42 statements and 8 quality indicators. Additional modifications from external stakeholders were incorporated to form the foundation for the proposed MHP.

INTERPRETATION

This MHP template will provide the basis for the design of an MHP toolkit, including specific recommendations for pediatric and obstetrical patients, and for hospitals with limited availability of blood components or means to achieve definitive hemorrhage control. We believe that harmonization of MHPs in our region will simplify training, increase uptake of evidence-based interventions, enhance communication, improve patient comfort and safety, and, ultimately, improve patient outcomes.

Agglutination testing for human erythrocyte product in the rhesus macaque

INTRODUCTION

There has been interest in using human blood products in nonhuman primate models of trauma to supplement human studies and to provide evidence to guide novel trauma resuscitation strategies. The compatibility of human RBCs has not been extensively studied in nonhuman primate species.

METHODS

Whole blood samples were collected from five healthy, nontransfused, not previously pregnant Chinese-bred rhesus macaques. The whole blood was centrifuged, and the plasma was decanted from each sample. Group O-negative human RBCs were mixed with the plasma from the rhesus macaque monkeys. Compatibility testing was performed by an immediate spin test and polyspecific and monospecific anti-human globulin (AHG) tests in glass tubes.

RESULTS

Immediate spin testing revealed three out of five plasma samples (60%) from rhesus macaques caused at least 1+ agglutination with the human RBCs. Polyspecific anti-human globulin (AHG) tests demonstrated that two of five plasma samples (40%) from rhesus macaques caused at least 1+ agglutination with the human RBC, while the monospecific AHG testing revealed that the incompatibility was caused by C3d, not IgG.

CONCLUSION

Human RBCs are not compatible with the plasma of some, but not all, Chinese-bred rhesus macaques.