Whole Blood Transfusion

Bleeding, Hemorrhagic Shock, and the Global Blood Supply

Hemorrhage is responsible for at least 40% of deaths after trauma and 27% of maternal deaths worldwide. Patients with hemorrhagic shock require attentive critical care and transfusion of blood products. Access to a safe and affordable blood supply is critical to providing safe surgical care. Traumatic injury, obstetric hemorrhage, and upper gastrointestinal bleed are the main causes of severe bleeding requiring transfusion. This article discusses the presentation and management of these causes across the world and provides a brief overview of the current challenges in maintaining a global blood supply.

Achieving optimal massive transfusion ratios: The trauma white board, whole blood, and liquid plasma. Real world low-tech solutions for a high stakes issue

BACKGROUND

It is well established that achieving optimal ratios of packed red blood cells (PRBC) to fresh frozen plasma (FFP) to platelet ratios during massive transfusion leads to improved outcomes but is difficult to accomplish.

METHODS

Between September 2018 and May 2019 our level 2 trauma center implemented 3 new processes to optimize transfusion ratios during massive transfusion protocol (MTP). Two units of low titer group O whole blood (LTOWB) were added as the first step to our MTP. Second, a dry erase board whiteboard was attached to each fluid warmer for real time recording of transfusions. Last, liquid plasma was incorporated into our MTP. We performed a retrospective review evaluating PRBC:FFP ratios for patients who had the massive transfusion protocol initiated and received 4 or more units of blood.

RESULTS

A total of 50 patients had the massive transfusion protocol initiated and received 4 or more units of PRBCs and/or LTOWB within 4 h of arrival. There were 21 patients evaluated prior to protocol changes and 29 patients after the changes. In the study group mean age, sex, pulse, systolic blood pressure (SBP), and injury severity scale (ISS) on admission were not different. In the pre-protocol (preP) group 90% of patients were blunt trauma and in the post-protocol group (postP) 72% were blunt trauma, p = 0. 22. For the preP group the mean units of PRBCs was 7.6 units and FFP 4.7 units. PostP the mean units of PRBCs was 11.4 units and FFP 10.0 units. PRBC/FFP ratios were 1.7 preP and 1.2 postP, p = 0.0072.

CONCLUSION

The institution of whole blood, use of the trauma white board, and the addition of liquid plasma to our transfusion services have allowed us to approach a 1:1 transfusion ratio during the course of our massive transfusions.

Blood Transfusion in Equids—A Practical Approach and Review

Simple Summary

Transfusion medicine is an accessible, technically simple, and often lifesaving tool that can be used in both field and hospital settings, in cases of significant bleeding or anemia. A thorough understanding of the indications, methodology and complications of blood transfusion allows the practitioner to identify cases where administration of whole blood is necessary, and how to safely perform the transfusion. This review collects the current literature surrounding blood transfusion into one readily accessible document to allow clinicians a comprehensive understanding of all aspects of equine blood transfusion, while serving as a reference for performing these procedures.

Abstract

Transfusion medicine is a crucial part of equine intensive and critical care. Blood transfusions can save lives in both acute and chronic cases of anemia, hemorrhage, and hemolysis. It is vital to have a comprehensive theoretical and practical understanding of the techniques, implications, risks, and complications. This review covers the physiology and pathophysiology of conditions requiring transfusion, as well as step by step guidance for practitioners of all experience levels. This review is designed to serve as a practical reference for those who are treating horses in either the field or hospital setting. It aims to provide both theoretical background and easy to locate formulae with guidance that is easy to refer to in a critical situation. When risks and benefits are well understood, these techniques can be confidently employed in critical situations to improve outcomes and save lives.

Logistics of managing a trauma whole blood inventory in a civilian level 1 trauma center

BACKGROUND

Institutional data on initiating and maintaining a low-titer O positive whole blood (LTOWB) inventory for the civilian trauma sector may help other institutions start a LTOWB program. This study from a level 1 trauma center with a hospital-based donor center highlights challenges faced during the collection, maintenance, and utilization of LTOWB.

STUDY DESIGN AND METHODS

Male O positive donors with low (≤1:100) anti-A and anti-B antibody titers were recruited for LTOWB collection. The daily inventory goal of 4 LTOWB units was kept in the emergency department refrigerator and transfused to adult male trauma patients. Unused units older than 10 days were reprocessed into packed red blood cells.

RESULTS

Of 900 donors screened, 61% qualified and 52% of eligible donors provided a collective total of 505 LTOWB units over 2.5 years. The number of collected units directly correlated with the availability of inventory; 42% of the units were transfused, 54% were reprocessed, and 4% were discarded. The inventory goal was maintained for 56% of the year 2018 and 83% of the year 2019. Over these 2 years, 52% of patients had their transfusion needs fully met, 41% had their needs partially met, and 6.5% did not have their needs met.

DISCUSSION

Initial challenges to LTOWB implementation were inventory shortages, low utilization rates, and failure to meet clinical demand. Proposed solutions include allowing for a higher yet safe titer, extending shelf life, expanding the donor pool, identifying barriers to utilization, and permitting use in female trauma patients beyond childbearing age.

The Norwegian blood preparedness project: A whole blood program including civilian walking blood banks for early treatment of patients with life-threatening bleeding in municipal health care services, ambulance services, and rural hospitals

Background

Civilian and military guidelines recommend early balanced transfusion to patients with life‐threatening bleeding to improve survival. To provide the best care to patients with hemorrhagic shock in regions with reduced access to evacuation, blood preparedness must be ensured also on a municipal health care level. The primary aim of the Norwegian Blood Preparedness project is to enable rural hospitals, prehospital ambulance services, and municipal health care services to start early balanced blood transfusions for patients with life‐threatening bleeding regardless of etiology.

Study Design and Methods

The project is designed based on three principles: (1) Early balanced transfusion should be provided for patients with life‐threatening bleeding, (2) Management of an emergency requires a planned and rehearsed day‐to‐day system for blood preparedness, and (3) A decentralized system is needed to ensure local self‐sufficiency in an emergency. We developed a system for education and training in blood‐based resuscitation with a focus on the municipal health care service.

Results

In this publication, we describe the implementation of emergency whole blood collections from a preplanned civilian walking blood bank in the municipal health care service. This includes donor selection, whole blood collection, emergency transfusion and quality assessment of practice.

Conclusion

We conclude that implementation of a Whole Blood based emergency transfusion program is feasible on all health care levels and that a preplanned civilian walking blood bank should be considered in locations were prolonged transport‐times may reduce access to blood transfusion for patients with life threatening bleeding.

Minimal impact of anticoagulant on in vitro whole blood quality throughout a 35-day cold-storage regardless of leukoreduction timing

BACKGROUND

There is increasing interest in leukoreduced whole blood (WB) as a transfusion product for trauma patients. In some jurisdictions, few leukoreduced filters are approved or appropriate for WB leukoreduction and quality information is therefore limited. This study assessed the impact of filtration timing of WB collected in CPDA-1 versus CPD on in vitro quality.

STUDY DESIGN AND METHODS

WB was collected in CPDA-1 or CPD and leukoreduction filtered either after 3-8 h (early) or 18-24 h (late) from stop bleed time. In vitro quality was assessed after filtration and throughout 5 weeks of storage at 4°C. Cell count and hemoglobin levels were determined by hematology analyzer, platelet activation and responsiveness to ADP by surface expression of P-selectin by flow cytometry, hemolysis by HemoCue, and metabolic parameters by blood gas analyzer. Hemostatic properties were assessed by rotational thromboelastometry. Plasma protein activities and clotting times were determined by automated coagulation.

RESULTS

Although there were some data points which showed statistically significant differences associated with anticoagulant choices or the filtration timing, no general trend in inferiority/performance could be discerned. After 35 days' storage, only clotting time, alpha angle and factor II in the early filtration arm comparing anticoagulants and prothrombin time and factor II in the CPDA-1 study arm comparing filtration timing showed a significant difference.

CONCLUSION

In vitro WB quality seems to be independent on the choice of anticoagulant and filtration timing supporting WB hold-times to up to 24 h, increasing operational flexibility for transfusion services.

The regional whole blood program in San Antonio, TX: A 3-year update on prehospital and in-hospital transfusion practices for traumatic and non-traumatic hemorrhage

Low titer type O Rh-D + whole blood (LTO + WB) has become a first-line resuscitation medium for hemorrhagic shock in many centers around the World. Showing early effectiveness on the battlefield, LTO + WB is used in both the pre-hospital and in-hospital settings for traumatic and non-traumatic hemorrhage resuscitation. Starting in 2018, the San Antonio Whole Blood Collaborative has worked to provide LTO + WB across Southwest Texas, initially in the form of remote damage control resuscitation followed by in-hospital trauma resuscitation. This program has since expanded to include pediatric trauma resuscitation, obstetric hemorrhage, females of childbearing potential, and non-traumatic hemorrhage. The objective of this manuscript is to provide a three-year update on the successes and expansion of this system and outline resuscitation challenges in special populations.

Implementation of a low-titer stored whole blood transfusion program for civilian trauma patients: Early experience and logistical challenges

INTRODUCTION

Cold-stored low titer group O whole blood (LTOWB) is increasingly utilized in the initial resuscitation of exsanguinating trauma patients. We report on our early experience with LTOWB, focusing on logistics, implementation challenges, and outcomes.

METHODS

In February, 2019, LTOWB was incorporated into the massive transfusion protocol (MTP) activated for trauma patients in the emergency department (ED.) Up to 4 units of LTOWB were included in the MTP cooler, depending on availability, and were transfused prior to transfusion of any other blood products from the MTP cooler. Demographics, injury characteristics, and outcomes were obtained, and the logistics of LTOWB availability were reviewed.

RESULTS

Over a 12-month period, MTP was activated for 74 trauma patients. Of those, 38 (51%) MTP included at least one unit of LTOWB, with 19/38 (50%) including 4 LTOWB units. A total of 177 units of LTOWB were purchased during the study period, and of those, 74 (42%) expired before use. Patients who received LTOWB had a similar mortality compared to those who received component therapy (39% vs. 47%; Odds Ratio [95% CI]: 0.7 [0.3, 2.0]; p = 0.72,) however, they were able to achieve a significantly higher plasma:pRBC ratio during the duration of MTP activation (mean [SD] 0.8 [0.2] vs. 0.4 [0.4]; mean difference [95% CI]: 0.4 [0.2, 0.5]; p < 0.01.) CONCLUSIONS: Our early experience with LTOWB transfusion demonstrates feasibility, but also highlights challenges with inventory management. These findings triggered changes to our protocol aiming at minimizing wastage. The use of LTOWB may yield a higher plasma:pRBC ratio early during the resuscitation period. Further investigation is required to explore whether this may yield a survival advantage.

LEVEL OF EVIDENCE

III (Therapeutic/Care Management).

The Mirasol Evaluation of Reduction in Infections Trial (MERIT): study protocol for a randomized controlled clinical trial

BACKGROUND

Transfusion-transmitted infections (TTIs) are a global health challenge. One new approach to reduce TTIs is the use of pathogen reduction technology (PRT). In vitro, Mirasol PRT reduces the infectious load in whole blood (WB) by at least 99%. However, there are limited in vivo data on the safety and efficacy of Mirasol PRT. The objective of the Mirasol Evaluation of Reduction in Infections Trial (MERIT) is to investigate whether Mirasol PRT of WB can prevent seven targeted TTIs (malaria, bacteria, human immunodeficiency virus, hepatitis B virus, hepatitis C virus, hepatitis E virus, and human herpesvirus 8).

METHODS

MERIT is a randomized, double-blinded, controlled clinical trial. Recruitment started in November 2019 and is expected to end in 2024. Consenting participants who require transfusion as medically indicated at three hospitals in Kampala, Uganda, will be randomized to receive either Mirasol-treated WB (n = 1000) or standard WB (n = 1000). TTI testing will be performed on donor units and recipients (pre-transfusion and day 2, day 7, week 4, and week 10 after transfusion). The primary endpoint is the cumulative incidence of one or more targeted TTIs from the Mirasol-treated WB vs. standard WB in a previously negative recipient for the specific TTI that is also detected in the donor unit. Log-binomial regression models will be used to estimate the relative risk reduction of a TTI by 10 weeks associated with Mirasol PRT. The clinical effectiveness of Mirasol WB compared to standard WB products in recipients will also be evaluated.

DISCUSSION

Screening infrastructure for TTIs in low-resource settings has gaps, even for major TTIs. PRT presents a fast, potentially cost-effective, and easy-to-use technology to improve blood safety. MERIT is the largest clinical trial designed to evaluate the use of Mirasol PRT for WB. In addition, this trial will provide data on TTIs in Uganda.

TRIAL REGISTRATION

Mirasol Evaluation of Reduction in Infections Trial (MERIT) NCT03737669 . Registered on 9 November 2018.

Impact of Incorporating Whole Blood into Hemorrhagic Shock Resuscitation: Analysis of 1,377 Consecutive Trauma Patients Receiving Emergency-Release Uncrossmatched Blood Products

BACKGROUND

Use of whole blood (WB) for trauma resuscitation has seen a resurgence. The purpose of this study was to investigate survival benefit of WB across a diverse population of bleeding trauma patients.

STUDY DESIGN

A prospective observational cohort study of injured patients receiving emergency-release blood products was performed. All adult trauma patients resuscitated between November 2017 and September 2020 were included. The WB group included patients receiving any group O WB units. The component (COMP) group received no WB units, instead relying on fractionated blood (red blood cells, plasma, and platelets). Univariate and multivariate analyses were performed. Given large observed differences in our regression model, post hoc adjustments with inverse probability of treatment were conducted and a propensity score created. Propensity scoring and Poisson regression supported these findings.

RESULTS

Of 1,377 patients receiving emergency release blood products, 840 received WB and 537 remained in the COMP arm. WB patients had higher Injury Severity Score (ISS; 27 vs 20), lower field blood pressure (103 vs 114), and higher arrival lactate (4.2 vs 3.5; all p < 0.05). Postarrival transfusions and complications were similar between groups, except for sepsis, which was lower in the WB arm (25 vs 30%, p = 0.041). Although univariate analysis noted similar survival between WB and COMP (75 vs 76%), logistic regression found WB was independently associated with a 4-fold increased survival (odds ratio [OR] 4.10, p < 0.001). WB patients also had a 60% reduction in overall transfusions (OR 0.38, 95% CI 0.21-0.70). This impact on survival remained regardless of location of transfusion, ISS, or presence of head injury.

CONCLUSION

In patients experiencing hemorrhagic shock, WB transfusion is associated with both improved survival and decreased overall blood utilization.

Cell Salvage in Oncological Surgery, Peripartum Haemorrhage and Trauma

Oncological surgery, obstetric haemorrhage and severe trauma are the most challenging conditions for establishing clinical recommendations for the use of cell salvage. When the likelihood of allogeneic transfusion is high, the intraoperative use of this blood-saving technique would be justified, but specific patient selection criteria are needed. The main concerns in the case of oncological surgery are the reinfusion of tumour cells, thereby increasing the risk of metastasis. This threat could be minimized, which may help to rationalize its indication. In severe peripartum haemorrhage, cell salvage has not proven cost-effective, damage control techniques have been developed, and, given the risk of fetomaternal alloimmunization and amniotic fluid embolism, it is increasingly out of use. In trauma, bleeding may originate from multiple sites, coagulopathy may develop, and it should be evaluated whether re-transfusion of autologous blood collected from uncontaminated organ cavities would be feasible. General safety measures include washing recovered blood and its passage through leukocyte depletion filters. To date, no well-defined indications for cell salvage have been established for these pathologies, but with accurate case selection and selective implementation, it could become safe and effective. Randomized clinical trials are urgently needed.

Cellular and Biochemical Effects of Combined X-Ray Radiation and Storage on Whole Blood

Background

Evaluating the impact of ionizing radiation on stored blood is relevant since blood banks are major assets in emergency conditions such as radiation incident/attack. This study aimed to fill our knowledge gap of combined radiation and storage effects on blood.

Methods

Blood collected from 16 anesthetized rats was anticoagulated, aliquoted into storage bags, and assigned to 8 groups using protocols combining storage (1-day vs 3-day 4^oC) plus irradiation (75 Gy vs 0 Gy - control). Bags were positioned inside an X-ray irradiator (MultiRad-350). Complete blood count, differential white blood cell count, biochemistry, and hemostasis were analyzed (≥7 bags/group).

Results

Na⁺, bicarbonate, glucose, and pH significantly reduced, while K⁺, Cl⁻, and lactate increased by storage. Coagulation measures were not significantly altered after radiation. White blood cell count and most cell types were numerically reduced after radiation, but changes were statistically significant only for monocytes. No significant alterations were noted in aggregation or rotational thromboelastometry parameters between irradiated and control.

Conclusions

Evaluating cellular/biochemical parameters aids in assessing stored blood adequacy after radiation. Data suggest that fresh or cold-stored blood can sustain up to 75 Gy without major critical parameter changes and may remain suitable for use in critically ill patients in military/civilian settings.

Assessment of bacterial growth in leukoreduced cold-stored whole blood supports overnight hold at room temperature prior to filtration: A pilot study

BACKGROUND AND OBJECTIVES

Whole blood (WB) transfusion has regained attention to treat trauma patients. We reported no significant changes in in vitro quality through 21 days of cold storage for leukoreduced WB (LCWB) when time to filtration was extended from 8 to 24 h from collection. This study evaluated the impact of extended WB-hold at room temperature (RT) prior to leukoreduction on proliferation of transfusion-relevant bacteria.

MATERIALS AND METHODS

WB units were spiked with suspensions of Klebsiella pneumoniae, Streptococcus pyogenes, Staphylococcus aureus and Listeria monocytogenes prepared in saline solution (SS) or trypticase soy broth (TSB) to a concentration of ~0.2 CFU/ml (N = 6). Spiked units were held at RT for 18-24 h before leukoreduction and cold-stored for 21 days. Bacterial growth was determined on days 2, 7, 14 and 21. In vitro quality of WB inoculated with unspiked diluents was assessed.

RESULTS

K. pneumoniae and S. pyogenes proliferated in WB prior to leukoreduction reaching concentrations ≤10² CFU/ml. These bacteria, however, did not proliferate during the subsequent cold storage. S. aureus did not survive in WB while L. monocytogenes reached a concentration of ~10² CFU/ml by day 21. LCWB in vitro quality was not affected by SS or TSB.

CONCLUSION

Extended WB-hold prior to leukoreduction allowed proliferation of bacteria able to resist immune clearance, although they did not grow to clinically significant levels. While L. monocytogenes proliferated in LCWB, clinically relevant concentrations were not reached by day 21. These data suggest that transfusing LCWB may not pose a significant bacterial contamination safety risk to transfusion patients.

Effect of Massive Transfusion Protocol on Coagulation Function in Elderly Patients with Multiple Injuries

Objective

To evaluate the effect of massive transfusion protocol on coagulation function in elderly patients with multiple injuries.

Methods

In this retrospective cohort study, clinical data were collected from a total of 94 elderly patients with multiple injuries, including 44 cases who received routine transfusion protocol (control group) and 50 cases who concurrently received massive transfusion protocol in our hospital (research group). The changes in platelet parameters, coagulation function, and organ dysfunction scores at admission and 24 h after transfusion were compared between the two groups. The 24-hour plasma and red blood cell transfusion volume, length of stay, complications, and mortality of the two groups were analyzed statistically.

Results

Twenty-four hours after blood transfusion, the hematocrit, platelets, and hemoglobin in the research group were higher than those in the control group, while the activated partial thromboplastin time, prothrombin time, thrombin time, fibrinogen, and scores of Marshall scoring system and Sequential Organ Failure Assessment were lower than those in the control group (P < 0.01). The 24-hour plasma transfusion volume was higher, and the length of intensive care unit (ICU) stay and total length of stay were lower in the research group compared with the control group (P < 0.01). No significant difference was found in the mortality rate between the research group and the control group (10.00% vs. 13.64%, P > 0.05). The incidence of complications in the research group was lower than that in the control group (12.00% vs. 31.82%, P < 0.05).

Conclusion

Massive transfusion protocol for elderly patients with multiple injuries can improve their coagulation function and platelet parameters, alleviate organ dysfunction, shorten length of ICU stay, and decrease the incidence of complications, which is conducive to improving the prognosis of patients.

The Alterations in Methylene Blue/Light-Treated Frozen Plasma Proteins Revealed by Proteomics

Introduction

The aim of this study was to investigate the modified proteins in methylene blue/light-treated frozen plasma (MB-FP) compared with fresh frozen plasma (FFP) in order to gain a better application of MB/light-treated plasma in clinic transfusion.

Methods

MB-FP and FFP were collected from Changchun central blood station, and a trichloroacetic acid/acetone precipitation method was used to remove albumin for the enrichment of lower abundance proteins. The plasma protein in MB-FP and FFP were separated using two-dimensional gel electrophoresis (2-DE) and the differentially expressed protein spots were analyzed using mass spectrometry. Finally, the differentially expressed proteins were tested using Western blot and enzyme-linked immunosorbent assay (ELISA).

Results

Approximately 14 differentially expressed protein spots were detected in the MB-FP, and FFP was chosen as the control. After 2-DE comparison analysis and mass spectrometry, 8 significantly differentially expressed protein spots were identified, corresponding to 6 different proteins, including complement C1r subcomponent (C1R), inter-alpha-trypsin inhibitor heavy chain H4 (ITI-H4), keratin, type II cytoskeletal 1 (KRT1), hemopexin (HPX), fibrinogen gamma chain (FGG), and transthyretin (TTR). Western blot showed no significant difference in the expression level of KRT1 between MB-FP and FFP (p > 0.05). Both Western blot and ELISA indicated that the level of HPX was significantly higher in FFP than in MB-FP (p < 0.05).

Conclusion

This comparative proteomics study revealed that some significantly modified proteins occur in MB-FP, such as C1R, ITI-H4, KRT1, HPX, FGG, and TTR. Our findings provide more theoretical data for using MB-FP in transfusion medicine. However, the relevance of the data for the transfusion of methylene blue/light-treated plasma remains unclear. The exact modification of these proteins and the effects of these modified proteins on their functions and their effects in clinical plasma infusion need to be further studied.

Is the whole greater than the sum of its parts? The implementation and outcomes of a whole blood program in Ecuador

BACKGROUND

Hemorrhagic shock is a major cause of mortality in low-income and middle-income countries (LMICs). Many institutions in LMICs lack the resources to adequately prescribe balanced resuscitation. This study aims to describe the implementation of a whole blood (WB) program in Latin America and to discuss the outcomes of the patients who received WB.

METHODS

We conducted a retrospective review of patients resuscitated with WB from 2013 to 2019. Five units of O+ WB were made available on a consistent basis for patients presenting in hemorrhagic shock. Variables collected included gender, age, service treating the patient, units of WB administered, units of components administered, admission vital signs, admission hemoglobin, shock index, Revised Trauma Score in trauma patients, intraoperative crystalloid (lactated Ringer's or normal saline) and colloid (5% human albumin) administration, symptoms of transfusion reaction, length of stay, and in-hospital mortality.

RESULTS

The sample includes a total of 101 patients, 57 of which were trauma and acute care surgery patients and 44 of which were obstetrics and gynecology patients. No patients developed symptoms consistent with a transfusion reaction. The average shock index was 1.16 (±0.55). On average, patients received 1.66 (±0.80) units of WB. Overall mortality was 13.86% (14 of 101) in the first 24 hours and 5.94% (6 of 101) after 24 hours.

DISCUSSION

Implementing a WB protocol is achievable in LMICs. WB allows for more efficient delivery of hemostatic resuscitation and is ideal for resource-restrained settings. To our knowledge, this is the first description of a WB program implemented in a civilian hospital in Latin America.

LEVEL OF EVIDENCE

Level IV.

Ranger O Low Titer (ROLO): Whole Blood Transfusion for Forward Deployed Units

First-time use of Ranger O Low Titer (ROLO) blood and implementation of a forward-walking blood bank using predetermined donors proved essential in the survival of a 33-year-old active duty soldier following a complex blast injury during combat operations. The patient sustained significant bone, soft tissue, and vascular damage and continued to deteriorate despite resuscitation with cold-stored whole blood (WB). Only after utilizing the ROLO battle drill and transfusing with fresh WB was the patient able to be stabilized and evacuated. In this case report, we discuss how ROLO walking blood bank takes the next step in aiding resuscitation, providing smaller, forward-deployed units with blood resupply without the administrative burden of storage, particularly in resource-scarce environments. We provide an overview of WB and contrast its use to that of component therapy. In conjunction with the Golden Hour, ROLO can be incorporated as the standard damage control resuscitation to reduce the risks of noncompressible hemorrhage. By taking precautionary steps in the pre-deployment setting, ROLO offers an invaluable alternative to conventional resuscitation.

Whole Blood Transfusion: Past, Present, and Future

Transfusion of whole blood largely was replaced by component therapy in the 1970s and 1980s. The recent military operations in Iraq and Afghanistan returned whole blood to military trauma care. Eventually, whole blood use was incorporated into some civilian trauma care. It has been utilized in several other civilian populations as well. Trials to compare whole blood to component therapy are ongoing.

Novel resuscitation strategies in patients with a pelvic fracture

Patients with a pelvic ring injury and hemodynamic instability can be challenging to manage with high rates of morbidity and mortality rates. Protocol-based resuscitation strategies are critical to successfully manage these potentially severely injured patients in a well-coordinated manner. While some aspects of treatment may vary slightly from institution to institution, it is critical to identify pelvic injuries and their associated injuries expediently. The first step at the scene of injury or in the trauma resuscitation bay should be the immediate application of a circumferential pelvic sheet or binder, initiation of physiologically optimal fluid resuscitation in the form 1:1:1 (pRBC:FFP:platelets) or whole blood, and to consider TXA as a safe adjunct to treat coagulopathy. Providers should have a very low threshold for emergent operative intervention in the form of pelvic external fixation and/or pelvic packing. This occurs in addition to simultaneous interventions addressing the other possible sources of bleeding in patients demonstrating signs of hemorrhagic shock and failure to respond to early resuscitation and external pelvic tamponade. Finally, while arterial injury is only present in a small percentage of patients with a pelvic ring injury, percutaneous vascular intervention with selective angiography and REBOA have been shown to be efficacious for patients with clinical indicators of arterial injury or who remain hemodynamically unstable despite external pelvic tamponade and packing to address venous bleeding. They should be performed when as early as possible for patients in true extremis limit further hemorrhage and allow resuscitation efforts to continue.

A Case Report of Combat Blast Injury Requiring Combat Casualty Care, Far-Forward ECMO, Air Transport, and All Levels of Military Critical Care

We describe a 34-year-old soldier who sustained a blast injury in Syria resulting in tracheal 5 cm tracheal loss, cervical spine and cord injury with tetraplegia, multiple bilateral rib fractures, esophageal injury, traumatic brain injury, globe evisceration, and multiple extremity soft tissue and musculoskeletal injuries including a left tibia fracture with compartment syndrome. An emergent intubation of the transected trachea was performed in the field, and the patient was resuscitated with whole blood prehospital. During transport to the Role 2, the patient required cardiopulmonary resuscitation for cardiac arrest. On arrival, he underwent a resuscitative thoracotomy and received a massive transfusion exclusively with whole blood. A specialized critical care team transported the patient to the Role 3 hospital in Baghdad, and the DoD extracorporeal membrane oxygenation (ECMO) team was activated secondary to his unstable airway and severe hypoxia secondary to pulmonary blast injury. The casualty was cannulated in Baghdad approximately 40 hours after injury with bifemoral cannulae in a venovenous configuration. He was transported from Iraq to the U.S. Army Institute of Surgical Research Burn Center in San Antonio without issue. Extracorporeal membrane oxygenation support was successfully weaned, and he was decannulated on ECMO day 4. The early and en route use of venovenous ECMO allowed for maintenance of respiratory support during transport and bridge to operative management and demonstrates the feasibility of prolonged ECMO transport in critically ill combat casualties.

Effect of leukoreduction and temperature on risk of bacterial growth in CPDA-1 whole blood: A study of Escherichia coli

BACKGROUND

Collection of non-leukoreduced citrate-phosphate-dextrose-adenine (CPDA-1) whole blood is performed in walking blood banks. Blood collected under field conditions may have increased risk of bacterial contamination. This study was conducted to examine the effects of WBC reduction and storage temperature on growth of Escherichia coli (ATCC® 25922™) in CPDA-1 whole blood.

METHODS

CPDA-1 whole blood of 450 ml from 10 group O donors was inoculated with E. coli. Two hours after inoculation, the test bags were leukoreduced with a platelet-sparing filter. The control bags remained unfiltered. Each whole blood bag was then split into three smaller bags for further storage at 2-6°C, 20-24°C, or 33-37°C. Bacterial growth was quantified immediately, 2 and 3 h after inoculation, on days 1, 3, 7, and 14 for all storage temperatures, and on days 21 and 35 for storage at 2-6°C.

RESULTS

Whole blood was inoculated with a median of 19.5 (range 12.0-32.0) colony-forming units per ml (CFU/ml) E. coli. After leukoreduction, a median of 3.3 CFU/ml (range 0.0-33.3) E. coli remained. In the control arm, the WBCs phagocytized E. coli within 24 h at 20-24°C and 33-37°C in 9 of 10 bags. During storage at 2-6°C, a slow self-sterilization occurred over time with and without leukoreduction.

CONCLUSIONS

Storage at 20-24°C and 33-37°C for up to 24 h before leukoreduction reduces the risk of E. coli-contamination in CPDA-1 whole blood. Subsequent storage at 2-6°C will further reduce the growth of E. coli.

A whole blood based resuscitation strategy in civilian medical services: Experience from a Norwegian hospital in the period 2017-2020

BACKGROUND

Civilian and military guidelines recommend early balanced transfusion to patients with life-threatening bleeding. Low titer group O whole blood was introduced as the primary blood product for resuscitation of massive hemorrhage at Haukeland University Hospital, Bergen, Norway, in December 2017. In this report, we describe the whole blood program and present results from the first years of routine use.

STUDY DESIGN AND METHODS

Patients who received whole blood from December 2017 to April 2020 were included in our quality registry for massive transfusions. Post-transfusion blood samples were collected to analyze isohemagglutinin (anti-A/-B) and hemolysis markers. Administration of other blood products, transfusion reactions, and patient survival (days 1 and 30) were recorded. User experiences were surveyed for both clinical and laboratory staff.

RESULTS

Two hundred and five patients (64% male and 36% female) received 836 units in 226 transfusion episodes. Patients received a mean of 3.7 units (range 1-35) in each transfusion episode. The main indications for transfusion were trauma (26%), gastrointestinal (22%), cardiothoracic/vascular (18%), surgical (18%), obstetric (11%), and medical (5%) bleeding. There was no difference in survival between patients with blood type O when compared with non-group O. Haptoglobin level was lower in the transfusion episodes for non-O group patients, however no clinical hemolysis was reported. No patients had conclusive transfusion-associated adverse events. Both clinical and laboratory staff preferred whole blood to component therapy for massive transfusion.

DISCUSSION

The experience from Haukeland University Hospital indicates that whole blood is feasible, safe, and effective for in-hospital treatment of bleeding.

Coagulation function of never frozen liquid plasma stored for 40 days

BACKGROUND

Never frozen liquid plasma (LP) has limited shelf life versus fresh frozen plasma (FFP) or plasma frozen within 24 h (PF24). Previous studies showed decreasing factor activities after Day (D)14 in thawed FFP but no differences between LP and FFP until D10. This study examined LP function through D40.

STUDY DESIGN AND METHODS

FFP and PF24 were stored at -20°C until assaying. LP was assayed on D5 then stored (4°C) for testing through D40. A clinical coagulation analyzer measured Factor (F)V, FVIII, fibrinogen, prothrombin time (PT), and activated partial thromboplastin time (aPTT). Thromboelastography (TEG) and thrombogram measured functional coagulation. Ristocetin cofactor assay quantified von Willebrand factor (vWF) activity. Residual platelets were counted.

RESULTS

FV/FVIII showed diminished activity over time in LP, while PT and aPTT both increased over time. LP vWF declined significantly by D7. Fibrinogen remained high through D40. Thrombin lagtime was delayed in LP but consistent to D40, while peak thrombin was significantly lower in LP but did not significantly decline over time. TEG R-time and angle remained constant. LP and PF24 (with residual platelets) had initially higher TEG maximum amplitudes (MA), but by D14 LP was similar to FFP.

CONCLUSION

Despite significant declines in some factors in D40 LP, fibrinogen concentration and TEG MA were stable suggesting stored LP provides fibrinogen similarly to frozen plasmas even at D40. LP is easier to store and prepare for prehospital transfusion, important benefits when the alternative is crystalloid.

Joint Trauma System, Defense Committee on Trauma, and Armed Services Blood Program consensus statement on whole blood

Hemorrhage is the most common mechanism of death in battlefield casualties with potentially survivable injuries. There is evidence that early blood product transfusion saves lives among combat casualties. When compared to component therapy, fresh whole blood transfusion improves outcomes in military settings. Cold-stored whole blood also improves outcomes in trauma patients. Whole blood has the advantage of providing red cells, plasma, and platelets together in a single unit, which simplifies and speeds the process of resuscitation, particularly in austere environments. The Joint Trauma System, the Defense Committee on Trauma, and the Armed Services Blood Program endorse the following: (1) whole blood should be used to treat hemorrhagic shock; (2) low-titer group O whole blood is the resuscitation product of choice for the treatment of hemorrhagic shock for all casualties at all roles of care; (3) whole blood should be available within 30 min of casualty wounding, on all medical evacuation platforms, and at all resuscitation and surgical team locations; (4) when whole blood is not available, component therapy should be available within 30 min of casualty wounding; (5) all prehospital medical providers should be trained and logistically supported to screen donors, collect fresh whole blood from designated donors, transfuse blood products, recognize and treat transfusion reactions, and complete the minimum documentation requirements; (6) all deploying military personnel should undergo walking blood bank prescreen laboratory testing for transfusion transmitted disease immediately prior to deployment. Those who are blood group O should undergo anti-A/anti-B antibody titer testing.

Civilian walking blood bank emergency preparedness plan

BACKGROUND

The current global pandemic has created unprecedented challenges in the blood supply network. Given the recent shortages, there must be a civilian plan for massively bleeding patients when there are no blood products on the shelf. Recognizing that the time to death in bleeding patients is less than 2 h, timely resupply from unaffected locations is not possible. One solution is to transfuse emergency untested whole blood (EUWB), similar to the extensive military experience fine-tuned over the last 19 years. While this concept is anathema in current civilian transfusion practice, it seems prudent to have a vetted plan in place.

METHODS AND MATERIALS

During the early stages of the 2020 global pandemic, a multidisciplinary and international group of clinicians with broad experience in transfusion medicine communicated routinely. The result is a planning document that provides both background information and a high-level guide on how to emergently deliver EUWB for patients who would otherwise die of hemorrhage.

RESULTS AND CONCLUSIONS

Similar plans have been utilized in remote locations, both on the battlefield and in civilian practice. The proposed recommendations are designed to provide high-level guidance for experienced blood bankers, transfusion experts, clinicians, and health authorities. Like with all emergency preparedness, it is always better to have a well-thought-out and trained plan in place, rather than trying to develop a hasty plan in the midst of a disaster. We need to prevent the potential for empty shelves and bleeding patients dying for lack of blood.

Management of non-compressible torso hemorrhage: An update

With the widespread adoption of advanced tourniquets, the mortality rate of limb wound hemorrhage has decreased significantly, and non-compressible torso hemorrhage has gradually occupied the leading position of potentially preventable death, both in military and civilian circumstances. With the emergence of novel hemostatic devices and materials, strategies for the management of non-compressible torso hemorrhage have changed significantly. This review summarizes the current treatment strategies and types of equipment for non-compressible torso hemorrhage and suggests future research directions, hoping to provide a comprehensive review for the medical personnel and researchers engaging in this field.

Practical Considerations for a Military Whole Blood Program

INTRODUCTION

Prehospital care in the combat environment has always been of great importance to the U.S. military, and trauma resuscitation has remained a cornerstone. More evidence continues to demonstrate the advantages of intervention with early transfusion of blood products at the point of injury. The military has recognized these benefits; as such, the Department of Defense Joint Trauma System and the Committee on Tactical Combat Casualty Care have developed new advanced resuscitation guidelines, which now encourage the use of whole blood (WB) in the prehospital setting.

MATERIALS AND METHODS

This general review of peer-reviewed journal articles was performed through an extensive electronic search from the databases of PubMed Central (MEDLINE) and the Cochrane Library.

RESULTS

Based on this literature search, the current evidence suggests that transfusion with WB is safe and efficacious. Additionally, soldier function is preserved after donating fresh WB in the field. Currently, the collection and implementation of WB is accomplished through several different protocol-driven techniques.

CONCLUSION

WB has become the favored transfusion product as it provides all of the components of blood in a convenient package that is easy to store and transport. Specifically, group O WB containing low titers of anti-A and -B antibodies has become the transfusion product of choice, offering the ability to universally fluid resuscitate patients despite not knowing their blood group. This new ability to obtain low titer group O WB has transformed the approach to the management of hemorrhagic shock in the prehospital combat environment.

Prehospital Whole Blood Resuscitation Reduces Fluid Requirement While Maintaining Critical Physiology in a Model of Penetrating Traumatic Brain Injury and Hemorrhage: Implications on Resource-Limited Combat Casualty Care

ABSTRACT

Prehospital resuscitation using whole blood (WB) is the standard of care for hemorrhagic shock (HS) but there is no consensus recommendation for resuscitation in the presence of traumatic brain injury (TBI) due to a lack of sufficient evidence. In order to evaluate the optimal resuscitation strategies for TBI+HS, Sprague-Dawley rats were randomized into four groups based on resuscitation fluid and prehospital mean arterial pressure (MAP) threshold (n = 9-10/group): Lactated Ringer's (LR)-60 mm Hg (LR60), LR-70 mm Hg (LR70), WB-60 mm Hg (WB60), WB-70 mm Hg (WB70). All groups received a frontal penetrating ballistic-like brain injury followed by a 35-min period of HS. During the prehospital phase, rats received an initial bolus of resuscitation fluid (WB or LR) followed by LR as needed to maintain MAP above the designated threshold for 90 min. During the in-hospital phase, rats received definitive resuscitation with shed WB. Physiological parameters were recorded continuously and cerebral edema was measured at 3 and 24 h postinjury. The WB60 group demonstrated a significantly lower prehospital fluid requirement compared WB70, LR60, and LR70 (P < 0.05). Compared to the respective LR groups, both the WB60 and WB70 groups also demonstrated improved MAP, cerebral perfusion pressure, brain tissue oxygen tension, and cerebral edema. The edema benefits were observed at 3 h, but not 24 h postinjury, and were localized to the injury site. Together, these results provide evidence that prehospital WB resuscitation and lower MAP resuscitation thresholds can reduce the prehospital fluid requirement while still maintaining critical cerebral physiology in a model of HS and concomitant TBI.

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.

Spontaneous Splenic Artery Rupture as the First Symptom of Systemic Amyloidosis

Spontaneous splenic rupture is a life-threatening condition leading to a rapidly progressing hypovolemic shock due to intra-abdominal blood loss, with a mortality rate of about 10%. Spontaneous splenic rupture can be caused by widely different disorders including acute and chronic infections, neoplastic disorders, and inflammatory noninfectious disorders. In this case report, we present a 67-year-old male patient with hemorrhagic shock caused by an acute bleeding from the splenic artery. The patient was massively transfused with blood products and fluids and underwent laparotomy for hemostatic control and clinical stabilization. Multiorgan involvement by amyloid light-chain amyloidosis (AL-amyloidosis) caused by plasma cell dyscrasia, specifically with infiltration of the spleen artery, was found to be the underlying cause of his life-threatening bleeding. Based on this case, we discuss the features of serious spleen bleeding, massive transfusion therapy in the intensive care setting, and AL-amyloidosis pathophysiology and treatment.

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.

The use of whole blood in traumatic bleeding: a systematic review

Hemostatic resuscitation is currently considered a standard of care for the management of life-threatening hemorrhage, but in some critical settings the access to high quantities of blood components is problematic. Whole blood (WB) transfusion has been proposed as an alternative modality for hemostatic resuscitation of traumatic major bleeding. To assess the efficacy and safety of WB in trauma-associated massive bleeding, we performed a systematic review of the literature. We selected studies comparing WB transfusions to transfusion of blood components (COMP) in massive trauma bleeding; both randomized clinical trial (RCT) and observational studies were considered. The outcomes were mortality (30-day/in-hospital and 24-h mortality) and adverse events/transfusion reactions. The effect sizes were crude odds ratio (OR), adjusted OR and hazard ratio (HR). The methodological quality of studies was assessed using the Cochrane Risk of Bias tool for RCTs, and the ROBIN-1 tool for observational studies. The overall quality of the available evidence was assessed with the GRADE system. One RCT (2 reports) and 6 cohort studies were included (3642 adult patients; 675 receiving WB, 2967 receiving COMP). Three studies were conducted in military setting, and 4 in civilian setting. In the overall analysis, 30-day/in-hospital and 24-h mortality did not differ significantly between groups (very low quality of the evidence due to high risk of bias, imprecision and inconsistency). After adjustment for baseline covariates in three cohort studies, the OR for mortality was significantly lower in WB recipients compared to COMP (OR 0.22; 95% CIs 0.10/0.45) (moderate grade of evidence). Adverse events and transfusion reactions were overlooked and not consistently reported. The available evidence does not allow to draw definite conclusions on the short-term and long-term efficacy and safety of WB transfusion compared to COMP transfusion. Further well designed research is needed.

Whole blood for blood loss: hemostatic resuscitation in damage control

Hemorrhagic shock and its complications are a major cause of death among trauma patients. The management of hemorrhagic shock using a damage control resuscitation strategy has been shown to decrease mortality and improve patient outcomes. One of the components of damage control resuscitation is hemostatic resuscitation, which involves the replacement of lost blood volume with components such as packed red blood cells, fresh frozen plasma, cryoprecipitate, and platelets in a 1:1:1:1 ratio. However, this is a strategy that is not applicable in many parts of Latin America and other low-and-middle-income countries throughout the world, where there is a lack of well-equipped blood banks and an insufficient availability of blood products. To overcome these barriers, we propose the use of cold fresh whole blood for hemostatic resuscitation in exsanguinating patients. Over 6 years of experience in Ecuador has shown that resuscitation with cold fresh whole blood has similar outcomes and a similar safety profile compared to resuscitation with hemocomponents. Whole blood confers many advantages over component therapy including, but not limited to the transfusion of blood with a physiologic ratio of components, ease of transport and transfusion, less volume of anticoagulants and additives transfused to the patient, and exposure to fewer donors. Whole blood is a tool with reemerging potential that can be implemented in civilian trauma centers with optimal results and less technical demand.

The Prehospital Evaluation and Care of Moderate/Severe TBI in the Austere Environment

Increased resource constraints secondary to a smaller medical footprint, prolonged evacuation times, or overwhelming casualty volumes all increase the challenges of effective management of traumatic brain injury (TBI) in the austere environment. Prehospital providers are responsible for the battlefield recognition and initial management of TBI. As such, targeted education is critical to efficient injury recognition, promoting both provider readiness and improved patient outcomes. When austere conditions limit or prevent definitive treatment, a comprehensive understanding of TBI pathophysiology can help inform acute care and enhance prevention of secondary brain injury. Field deployable, noninvasive TBI assessment and monitoring devices are urgently needed and are currently undergoing clinical evaluation. Evidence shows that the assessment, monitoring, and treatment in the first few hours and days after injury should focus on the preservation of cerebral perfusion and oxygenation. For cases where medical management is inadequate (eg, evidence of an enlarging intracranial hematoma), guidelines have been developed for the performance of cranial surgery by nonneurosurgeons. TBI management in the austere environment will continue to be a challenge, but research focused on improving evidence-based monitoring and therapeutic interventions can help to mitigate some of these challenges and improve patient outcomes.

Whole Blood Administration: Comparison of In Vitro Platelet Function of Pressure Bag, Pressure Bag With Fluid Warming Device, and Rapid Infuser Methods

BACKGROUND

Use of low-titer group O whole blood for emergent transfusion of patients with unknown blood type became AABB approved in January 2018. Since that time, there is increasing use of whole blood in massive transfusion protocols. Whole blood stored at refrigerator temperature (2-4 °C) contains functional platelets that some research proposes may provide better clot dynamics than standard platelets, which are stored at room temperature (20-24 °C). Conventional teaching does not promote infusion of platelet products with pressure or warming, due to concerns of activation and subsequent inactivity of the infused platelets. Although a few reports found no significant changes in platelet function with warming or pressure during infusion of conventional room-temperature-stored platelets, there is limited data to support use of warming or pressure for infusion of whole blood products containing cold-stored platelets.

METHODS

This study design is to evaluate and compare three commonly used methods of administering blood products in a massive transfusion setting for their potential effects on platelets contained within whole blood units (pressure bag alone, pressure bag with fluid warming line, and rapid infuser).

RESULTS

Platelet function of 10 units tested pre- and post-infusion by thromboelastography (TEG) and platelet aggregation studies found no significant difference in platelet activity pre- and post-infusion with any of the three methods evaluated.

CONCLUSIONS

This study supports the use of rapid infuser or pressure bag devices (with or without warming) as acceptable for infusion of whole blood products. Infusion of whole blood with warming is preferable to prevent potential transfusion-associated hypothermia.

Fresh whole blood from walking blood banks for patients with traumatic hemorrhagic shock: A systematic review and meta-analysis

BACKGROUND

Whole blood is optimal for resuscitation of traumatic hemorrhage. Walking Blood Banks provide fresh whole blood (FWB) where conventional blood components or stored, tested whole blood are not readily available. There is an increasing interest in this as an emergency resilience measure for isolated communities and during crises including the coronavirus disease 2019 pandemic. We conducted a systematic review and meta-analysis of the available evidence to inform practice.

METHODS

Standard systematic review methodology was used to obtain studies that reported the delivery of FWB (PROSPERO registry CRD42019153849). Studies that only reported whole blood from conventional blood banking were excluded. For outcomes, odds ratios (ORs) and 95% confidence interval (CI) were calculated using random-effects modeling because of high risk of heterogeneity. Quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation system.

RESULTS

Twenty-seven studies published from 2006 to 2020 reported >10,000 U of FWB for >3,000 patients (precise values not available for all studies). Evidence for studies was "low" or "very low" except for one study, which was "moderate" in quality. Fresh whole blood patients were more severely injured than non-FWB patients. Overall, survival was equivalent between FWB and non-FWB groups for eight studies that compared these (OR, 1.00 [95% CI, 0.65-1.55]; p = 0.61). However, the highest quality study (matched groups for physiological and injury characteristics) reported an adjusted OR of 0.27 (95% CI, 0.13-0.58) for mortality for the FWB group (p < 0.01).

CONCLUSION

Thousands of units of FWB from Walking Blood Banks have been transfused in patients following life-threatening hemorrhage. Survival is equivalent for FWB resuscitation when compared with non-FWB, even when patients were more severely injured. Evidence is scarce and of relative low quality and may underestimate potential adverse events. Whereas Walking Blood Banks may be an attractive resilience measure, caution is still advised. Walking Blood Banks should be subject to prospective evaluation to optimize care and inform policy.

LEVEL OF EVIDENCE

Systematic/therapeutic, level 3.

Whole blood haemostatic function throughout a 28-day cold storage period: an in vitro study

BACKGROUND

In recent years, there has been renewed interest in whole blood (WB) transfusion, particularly in damage control resuscitation, in part due to the ability to provide the adequate ratio of blood components in a single transfusion. However, there is insufficient evidence to suggest that WB units maintain their haemostatic function during storage, which could compromise their quality and efficacy if transfused. Here, we evaluate the in vitro haemostatic function of stored WB units over a 28-day refrigeration period.

METHODS

Standard WB units were collected from healthy volunteers and stored at 4°C for 28 days. Samples were collected from each unit on several days throughout the storage period and tested for complete blood count (CBC), WB aggregation, clot kinetics as measured by thromboelastography (TEG), closure time and plasma-free haemoglobin.

RESULTS

Throughout the storage period, there were gradual, significant decreases in platelet count and function, including WB aggregation in response to collagen (P < 0·05) and closure time with epinephrine (P < 0·0005). Plasma-free haemoglobin increased substantially (by 163%) throughout the storage period. However, TEG results remained relatively stable for 3 weeks, indicating possible preservation of haemostatic function during that time.

CONCLUSION

This study shows that clot kinetics (as measured by TEG) in WB units stored at 4°C are preserved for up to 21 days. However, high levels of free haemoglobin raise concern for the potential risks of transfusing stored WB. Clinical studies are required to evaluate optimal storage times and outcomes of patients resuscitated with WB as compared to blood components.

Sex- and Gender-Related Factors in Blood Product Transfusions

Blood products are indicated for a plethora of conditions in several settings, with a variety of products available for transfusion, from highly processed specific components to whole blood. Matching the donor product to the recipient is crucial in avoiding serious transfusion reactions, with the extent of matching depending on the physiological need, setting, and product. There are important factors related to sex and gender differences in donated blood products, adverse reactions to those products, interplay with underlying pathology, as well as sociocultural differences in the collection. This article will review key sex- and gender-specific research related to the use of blood products with an emphasis on the acute care setting.

Extending existing recommended military casualty evacuation timelines will likely increase morbidity and mortality: a UK consensus statement

INTRODUCTION

Future conflicts may have limited use of aviation-based prehospital emergency care for evacuation. This will increase the likelihood of extended evacuation timelines and an extended hold at a forward hospital care facility following the completion of damage control surgery or acute medical interventions.

METHODS

A three-round Delphi Study was undertaken using a panel comprising 44 experts from the UK armed forces including clinicians, logisticians, medical planners and commanders. The panel was asked to consider the effect of an extended hold at Deployed Hospital Care (Forward) from the current 2-hour timeline to +4, +8, +12 and +24 hours on a broad range of clinical and logistical issues. Where 75% of respondents had the same opinion, consensus was accepted. Areas where consensus could not be achieved were used to identify future research priorities.

RESULTS

Consensus was reached that increasing timelines would increase the personnel, logistics and equipment support required to provide clinical care. There is a tipping point with a prolonged hold over 8 hours, after which the greatest number of clinical concerns emerge. Additional specialties of surgeons other than general and orthopaedic surgeons will likely be required with holds over 24 hours, and robust telemedicine would not negate this requirement.

CONCLUSIONS

Retaining acute medical emergencies at 4 hours, and head injuries was considered a particular risk. This could potentially be mitigated by an increased forward capacity of some elements of medical care and availability of a CT scanner and intracranial pressure monitoring at over 12 hours. Any efforts to mitigate the effects of prolonged timelines will come at the expense of an increased logistical burden and a reduction in mobility. Ultimately the true effect of prolonged timelines can only be answered by close audit and analysis of clinical outcomes during future operations with an extended hold.

Improved survival in critically injured combat casualties treated with fresh whole blood by forward surgical teams in Afghanistan

BACKGROUND

The objective of this study was to assess transfusion strategies and outcomes, stratified by the combat mortality index, of casualties treated by small surgical teams in Afghanistan. Resuscitation that included warm fresh whole blood (FWB) was compared to blood component resuscitation.

STUDY DESIGN AND METHODS

Casualties treated by a Role 2 surgical team in Afghanistan from 2008 to 2014 who received 1 or more units of red blood cells (RBCs) or FWB were included. Patients were excluded if they had incomplete data or length of stay less than 30 minutes. Patients were separated into two groups: 1) received FWB and 2) did not receive FWB; moreover, both groups potentially received plasma, RBCs, and platelets. The analysis was stratified by critically versus noncritically injured patients using the prehospital combat mortality index. Kaplan-Meier plot, log-rank test, and multivariable Cox regression were performed to compare survival.

RESULTS

In FWB patients, median units of FWB and total blood product were 4.0 (interquartile range [IQR], 2.0-7.0) and 16.0 (IQR, 10.0-28.0), respectively. The Kaplan-Meier plot demonstrated that survival was similar between FWB (79.1%) and no-FWB (74.5%) groups (p = 0.46); after stratifying patients by the combat mortality index, the risk of mortality was increased in the no-FWB group (hazard ratio, 2.8; 95% confidence interval, 1.2-6.4) compared to the FWB cohort.

CONCLUSION

In forward-deployed environments, where component products are limited, FWB has logistical advantages and was associated with reduced mortality in casualties with a critical combat mortality index. Additional analysis is needed to determine if these effects of FWB are appreciable in all trauma patients or just in those with severe physiologic derangement.

From battlefront to homefront: creation of a civilian walking blood bank

Hemorrhagic shock remains the leading cause of preventable death on the battlefield, despite major advances in trauma care. Early initiation of balanced resuscitation has been shown to decrease mortality in the hemorrhaging patient. To address transfusion limitations in austere environments or in the event of multiple casualties, walking blood banks have been used in the combat setting with great success. Leveraging the success of the region-wide whole blood program in San Antonio, Texas, we report a novel plan that represents a model response to mass casualty incidents.