Raising the standards on whole blood

Use of low titer O whole blood in infants and young children undergoing cardiac surgery with cardiopulmonary bypass

BACKGROUND

Low titer group O whole blood (LTOWB) is commonly used for severe bleeding in trauma patients. LTOWB may also benefit young children requiring cardiac surgery with cardiopulmonary bypass (CPB) at risk of severe bleeding.

STUDY DESIGN AND METHODS

In this retrospective study, children <2 years old who underwent cardiac surgery with CPB were included. Comparisons were performed between those receiving component therapy (CT) versus those receiving LTOWB plus CT (LTOWB+CT). Outcomes included drainage tube (DT) output and total transfusion volumes. Optimization-based weighting was used for adjusted analyses between groups.

RESULTS

There were 117 patients transfused with only CT and 127 patients transfused with LTOWB+CT. In the LTOWB+CT group, 66 were Group non-O and 61 were Group O. Total transfusion volumes given from the start of the operation until the first 24 h in the cardiac intensive care unit was a median (IQR) 41 (10, 93) mL/kg in the CT group and 48 (28, 77) mL/kg in the LTOWB+CT group, (p = .28). Median (IQR) DT output was 22 (15-32) in CT versus 22 (16-28) in LTOWB+CT groups, (p = .27). There were no differences in death, renal failure and a composite of death and renal failure between the two groups, but there were statistically fewer re-explorations for bleeding in the LTOWB+CT group (p < .001).

CONCLUSIONS

The use of LTOWB appears to be safe in <2 years old undergoing cardiac surgery and may reduce re-explorations for severe bleeding. Large trials are needed to determine the efficacy and safety of LTOWB in this population with severe bleeding.

The Efficacy of Low-Titer Group O Whole Blood Compared With Component Therapy in Civilian Trauma Patients: A Meta-Analysis

OBJECTIVES

To assess if transfusion with low-titer group O whole blood (LTOWB) is associated with improved early and/or late survival compared with component blood product therapy (CT) in bleeding trauma patients.

DATA SOURCES

A systematic search of PubMed, CINAHL, and Web of Science was performed from their inception through December 1, 2023. Key terms included injury, hemorrhage, bleeding, blood transfusion, and whole blood.

STUDY SELECTION

All studies comparing outcomes in injured civilian adults and children who received LTOWB versus CT were included.

DATA EXTRACTION

Data including author, publication year, sample size, total blood volumes, and clinical outcomes were extracted from each article and reported following the Meta-analysis Of Observational Studies in Epidemiology guidelines. Main outcomes were 24-hour (early) and combined 28-day, 30-day, and in-hospital (late) mortality rates between recipients of LTOWB versus CT, which were pooled using random-effects models.

DATA SYNTHESIS

Of 1297 studies reviewed, 24 were appropriate for analysis. Total subjects numbered 58,717 of whom 5,164 received LTOWB. Eleven studies included adults-only, seven included both adults and adolescents, and six only included children. The median (interquartile range) age for patients who received LTOWB and CT was 35 years (24-39) and 35.5 years (23-39), respectively. Overall, 14 studies reported early mortality and 22 studies reported late mortality. LTOWB was associated with improved 24-hour survival (risk ratios [RRs] [95% CI] = 1.07 [1.03-1.12]) and late (RR [95% CI] = 1.05 [1.01-1.09]) survival compared with component therapy. There was no evidence of small study bias and all studies were graded as a moderate level of bias.

CONCLUSIONS

These data suggest hemostatic resuscitation with LTOWB compared with CT improves early and late survival outcomes in bleeding civilian trauma patients. The majority of subjects were injured adults; multicenter randomized controlled studies in injured adults and children are underway to confirm these findings.

What's new in whole blood resuscitation? In the trauma bay and beyond

PURPOSE OF REVIEW

Transfusion therapy commonly supports patient care during life-threatening injury and critical illness. Herein we examine the recent resurgence of whole blood (WB) resuscitation for patients in hemorrhagic shock following trauma and other causes of severe bleeding.

RECENT FINDINGS

A growing body of literature supports the use of various forms of WB for hemostatic resuscitation in military and civilian trauma practice. Different types of WB include warm fresh whole blood (FWB) principally used in the military and low titer O cold stored whole blood (LTOWB) used in a variety of military and civilian settings. Incorporating WB initial resuscitation alongside subsequent component therapy reduces aggregate blood product utilization and improves early mortality without adversely impacting intensive care unit length of stay or infection rate. Applications outside the trauma bay include prehospital WB and use in patients with nontraumatic hemorrhagic shock.

SUMMARY

Whole blood may be transfused as FWB or LTOWB to support a hemostatic approach to hemorrhagic shock management. Although the bulk of WB resuscitation literature has appropriately focused on hemorrhagic shock following injury, extension to other etiologies of severe hemorrhage will benefit from focused inquiry to address cost, efficacy, approach, and patient-centered outcomes.

Maintaining a whole blood-centered transfusion improves survival in hemorrhagic resuscitation

BACKGROUND

Whole blood (WB) transfusion has been shown to improve mortality in trauma resuscitation. The optimal ratio of packed red blood cells (pRBC) to WB in emergent transfusion has not been determined. We hypothesized that a low pRBC/WB transfusion ratio is associated with improved survival in trauma patients.

METHODS

We analyzed the 2021 Trauma Quality Improvement Program (TQIP) database to identify patients who underwent emergent surgery for hemorrhage control and were transfused within 4 hours of hospital arrival, excluding transfers or deaths in the emergency department. We stratified patients based on pRBC/WB ratios. The primary outcome was mortality at 24 hours. Logistic regression was performed to estimate odds of mortality among ratio groups compared with WB alone, adjusting for injury severity, time to intervention, and demographics.

RESULTS

Our cohort included 17,562 patients; of those, 13,678 patients had only pRBC transfused and were excluded. Fresh frozen plasma/pRBC ratio was balanced in all groups. Among those who received WB (n = 3,884), there was a significant increase in 24-hour mortality with higher pRBC/WB ratios (WB alone 5.2%, 1:1 10.9%, 2:1 11.8%, 3:1 14.9%, 4:1 20.9%, 5:1 34.1%, p = 0.0001). Using empirical cutpoint estimation, we identified a 3:1 ratio or less as an optimal cutoff point. Adjusted odds ratios of 24-hour mortality for 4:1 and 5:1 groups were 2.85 (95% confidence interval [CI], 1.19-6.81) and 2.89 (95% CI, 1.29-6.49), respectively. Adjusted hazard ratios of 24-hour mortality were 2.83 (95% CI, 1.18-6.77) for 3:1 ratio, 3.67 (95% CI, 1.57-8.57) for 4:1 ratio, and 1.97 (95% CI, 0.91-4.23) for 5:1 ratio.

CONCLUSION

Our analysis shows that higher pRBC/WB ratios at 4 hours diminished survival benefits of WB in trauma resuscitation. Further efforts should emphasize this relationship to optimize trauma resuscitation protocols.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Empiric Cryoprecipitate Transfusion in Patients with Severe Hemorrhage: Results from the US Experience in the International CRYOSTAT-2 Trial

BACKGROUND

Hypofibrinogenemia has been shown to predict massive transfusion and is associated with higher mortality in severely injured patients. However, the role of empiric fibrinogen replacement in bleeding trauma patients remains controversial. We sought to determine the effect of empiric cryoprecipitate as an adjunct to a balanced transfusion strategy (1:1:1).

STUDY DESIGN

This study is a subanalysis of patients treated at the single US trauma center in a multicenter randomized controlled trial. Trauma patients (more than 15 years) were eligible if they had evidence of active hemorrhage requiring emergent surgery or interventional radiology, massive transfusion protocol (MTP) activation, and received at least 1 unit of blood. Transfer patients, those with injuries incompatible with life, or those injured more than 3 hours earlier were excluded. Patients were randomized to standard MTP (STANDARD) or MTP plus 3 pools of cryoprecipitate (CRYO). Primary outcomes included all-cause mortality at 28 days. Secondary outcomes were transfusion requirements, intraoperative and postoperative coagulation laboratory values, and quality-of-life measures (Glasgow outcome score-extended).

RESULTS

Forty-nine patients (23 in the CRYO group and 26 in the STANDARD group) were enrolled between May 2021 and October 2021. Time to randomization was similar between groups (14 vs 24 minutes, p = 0.676). Median time to cryoprecipitate was 41 minutes (interquartile range 37 to 48). There were no differences in demographics, arrival physiology, laboratory values, or injury severity. Intraoperative and ICU thrombelastography values, including functional fibrinogen, were similar between groups. There was no benefit to CRYO with respect to post-emergency department transfusions (intraoperative and ICU through 24 hours), complications, Glasgow outcome score, or mortality.

CONCLUSIONS

In this study of severely injured, bleeding trauma patients, empiric cryoprecipitate did not improve survival or reduce transfusion requirements. Cryoprecipitate should continue as an "on-demand" addition to a balanced transfusion strategy, guided by laboratory values and should not be given empirically.

Seeking a Relevant Description of Major Trauma Bleeding: Comparison of Four Major Bleeding Definitions

BACKGROUND

The traditional definition of massive transfusion is 10 red blood cell units transfused within 24 hr. This definition has been faulted for excluding patients who die early from exsanguination. Alternative major bleeding definitions in the trauma literature include time-based (e.g., Resuscitation Intensity) and event based (e.g., Sharpe) transfusion thresholds.

OBJECTIVE

The study objective was to compare four definitions of major bleeding, including a modification to the Sharpe definition, on clinically relevant processes and outcomes.

METHODS

This is a retrospective cohort study of adult trauma patients admitted from the field to a Level I trauma center from 2014 to 2019. Data sources were the trauma registry, blood bank, and electronic medical records. Transfusion thresholds were defined as follows: Resuscitation Intensity-4 units of any combination of crystalloids, colloids, or blood products within the first 30 min of arrival; Sharpe-10 red blood cell units from trauma bay presentation to inpatient admission (a proxy for the interval of hemorrhage control); Modified Sharpe-10 units of any combination of blood products during the same interval. The study analysis consisted of descriptive statistics.

RESULTS

The cohort contained 187 subjects. Of 39 deaths, 28 (72%) occurred within 6 hr following arrival. Modified Sharpe captured 27 (96%) of these 28 subjects, whereas Resuscitation Intensity captured 20 (71%). Sharpe and the traditional definition each captured 22 subjects (79%). Modified Sharpe captured 17%-25% of deaths missed by the other definitions.

CONCLUSION

Modified Sharpe may optimally indicate major bleeding during trauma resuscitation.

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.

Incompatible plasma transfusion is not associated with increased mortality in civilian trauma patients

BACKGROUND

The introduction of low titer group O whole blood (LTOWB) that contains potentially ABO-incompatible plasma and the increasing use of group A plasma, due to shortages of AB plasma, in trauma patients whose ABO group is unknown could put the recipients of incompatible plasma at risk of increased morbidity and mortality. This study evaluated civilian trauma patient outcomes following receipt of incompatible plasma.

METHODS

One trauma center's patient contributions to three multicenter studies of different trauma resuscitation strategies was analyzed; these patients were separated into two groups based on receipt of only compatible plasma versus receipt of any quantity of incompatible plasma. Multivariate analysis was performed to determine if receipt of incompatible plasma was associated with 24-hour or 30-day mortality.

RESULTS

There were 347 patients eligible for this secondary analysis with 167 recipients of only compatible plasma and 180 recipients of incompatible plasma. The two groups were well matched demographically and on both prehospital and hospital arrival vital signs. The median (IQR) volume of incompatible plasma received by these patients was 684 ml (342, 1229). There was not a significant difference between the groups in 24-hour and 30-day mortality, nor in in-hospital or intensive care unit lengths of stay. In the Cox proportional-hazards regression model for both 24-hour and 30-day survival, receipt of incompatible plasma was not independently predictive of either mortality endpoint.

CONCLUSION

Receipt of incompatible plasma was not independently associated with increased mortality in trauma patients. Prospective studies are needed to confirm these findings.

Low-titer group O whole blood in military ground ambulances: Lessons from the Israel Defense Forces initial experience

BACKGROUND

Cold-stored low-titer group O whole blood (LTOWB) has become increasingly utilised in both prehospital and in-hospital settings for resuscitation of traumatic haemorrhage. However, implementing the use of LTOWB to ground medical teams has been limited due to logistic challenges.

METHODS

In 2022, the Israel Defense Forces (IDF) started using LTOWB in ambulances for the first time in Israel. This report details the initial experience of this rollout and presents a case-series of the first patients treated with LTOWB.

RESULTS

Between January-December 2022, seven trauma patients received LTOWB administered by ground IDF intensive care ambulances after presenting with profound shock. Median time from injury to administration of LTOWB was 35 min. All patients had evidence of severe bleeding upon hospital arrival with six undergoing damage control laparotomy and all but one surviving to discharge.

CONCLUSIONS

The implementation of LTOWB in ground medical units is in its early stages, but continued experience may demonstrate its feasibility, safety, and effectiveness in the prehospital setting. Further research is necessary to fully understand the indications, methodology, and benefits of LTOWB in resuscitating severely injured trauma patients in this setting.

In vitro quality and hemostatic function of cold-stored CPDA-1 whole blood after repeated transient exposure to 28°C storage temperature

Background

Blood products are frequently exposed to room temperature or higher for longer periods than permitted by policy. We aimed to investigate if this resulted in a measurable effect on common quality parameters and viscoelastic hemostatic function of cold stored CPDA‐1 whole blood.

Study Design and Methods

450 ml of whole blood from 16 O Rh(D) positive donors was collected in 63 ml of CPDA‐1 and stored cold. Eights bags were exposed to five weekly 4‐h long transient temperature changes to 28°C. Eight bags were stored continuously at 4°C as a control. Samples were collected at baseline on day 1, after the first cycle on day 1 and weekly before each subsequent cycle (day 7, 14, 21, 28 and 35). Hemolysis, hematological parameters, pH, glucose, lactate, potassium, thromboelastography, INR, APTT, fibrinogen, and factor VIII were measured.

Results

CPDA‐1 whole blood repeatedly exposed to 28°C did not show reduced quality compared to the control group on day 35. Two units in the test group had hemolysis of 1.1% and 1.2%, and two in the control group hemolysis of 0.8%. Remaining thromboelastography clot strength (MA) on day 35 was 51.7 mm (44.8, 58.6) in the test group and 46.1 (41.6, 50.6) in the control group (p = .023). Platelet count was better preserved in the test group (166.7 [137.8, 195.6] vs. 117.8 [90.3, 145.2], p = .018). One sample in the test group was positive for Cutibacterium acnes on day 35 + 6.

Conclusion

Hemolysis findings warrant further investigation. Other indicators of quality were not negatively affected.

Low titer Group O whole blood utilization in pediatric trauma resuscitation: A National Survey

BACKGROUND

Renewed interest in low titer group O whole blood (LTOWB) transfusion has led to increased utilization in adult trauma centers; little is known regarding LTOWB use in pediatric centers.

STUDY DESIGN AND METHODS

A survey of LTOWB utilization at American pediatric level 1 trauma centers.

RESULTS

Responses were received from 43/72 (60%) centers. These institutions were primarily urban (84%) and pediatric-specific (58%). There were 16% (7/43) centers using LTOWB, 7% (3/43) imminently initiating an LTOWB program, 47% (20/43) with interest but no current plan to develop a LTOWB program, and 30% (13/43) with no immediate interest in an LTOWB program. For the hospitals actively or imminently using LTOWB, 70% (3/10) have a minimum recipient weight criterion, 60% (6/10) have a minimum age criterion, and 70% (7/10) restrict the maximum volume transfused. Before the patient's RhD type becomes known, 30% (3/10) use RhD negative LTOWB for males and females, 40% (4/10) use RhD positive LTOWB for males and RhD negative LTOWB for females, 20% (2/10) use RhD positive LTOWB for males and RhD negative RBCs for females, and 10% (1/10) use RhD positive LTOWB for both males and females. Maximum LTOWB storage duration was 14-35 days and units nearing expiration were used for non-trauma patients (40%), processed to RBC (40%), and/or discarded (40%). The most common barriers to implementation were concerns about inventory management (37%), wastage (35%), infrequent use (33%), cost (21%) and unclear efficacy (14%).

CONCLUSION

LTOWB utilization is increasing in pediatric level 1 trauma centers in the United States.

Receipt of at least 4 units of low titer group O whole blood with titer <100 does not lead to hemolysis in adult trauma patients

BACKGROUND

The serological safety of transfusing low titer group O whole blood (LTOWB) with an anti-A and anti-B titer of <100 was evaluated in group O and non-group O trauma recipients.

METHODS

Civilian adult trauma patients who received ≥4 units of leukoreduced LTOWB during their initial resuscitation and who survived for >24 h after admission at two level 1 trauma centers were included in this retrospective study. Lactate dehydrogenase (LDH), total bilirubin, haptoglobin, potassium, creatinine were evaluated on the day of LTOWB transfusion (day 0) and on the next 3 days.

RESULTS

There were 77 injured recipients evaluated: 39 non-group O and 38 group O. The median (IQR) number of transfused LTOWB units was 4 (4-6) and 4 (4-5), respectively, and the maximum number of units was 8 and 11, respectively. The non-group O patients received a median (IQR) volume of 1710 ml (1368-2070) of ABO-incompatible plasma. Comparing non-group O to group O recipients, there were no significant differences in the median haptoglobin, LDH, or creatinine concentrations at any time point. The median concentration of total bilirubin was significantly higher amongst the non-group O recipients on days 1 and 2, while on day 0 the median potassium concentration was significantly higher amongst the group O recipients. All median elevated values were within the laboratory's normal range. Amongst the non-group O recipients there were no reported transfusion reactions.

CONCLUSION

Receiving at least four LTOWB units (anti-A&B titer <100) was not associated with biochemical/clinical evidence of hemolysis in adult trauma patients.

Prehospital Plasma Transfusion: What Does the Literature Show?

Background

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

Summary

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

Key Messages

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

Estimating the risks of prehospital transfusion of D-positive whole blood to trauma patients who are bleeding in England

Background and Objectives

D‐negative red cells are transfused to D‐negative females of childbearing potential (CBP) to prevent haemolytic disease of the foetus and newborn (HDFN). Transfusion of low‐titre group O whole blood (LTOWB) prehospital is gaining interest, to potentially improve clinical outcomes and for logistical benefits compared to standard of care. Enhanced donor selection requirements and reduced shelf‐life of LTOWB compared to red cells makes the provision of this product challenging.

Materials and Methods

A universal policy change to the use of D‐positive LTOWB across England was modelled in terms of risk of three specific harms occurring: risk of haemolytic transfusion reaction now or in the future, and the risk of HDFN in future pregnancies for all recipients or D‐negative females of CBP.

Results

The risk of any of the three harms occurring for all recipients was 1:14 × 10³ transfusions (credibility interval [CI] 56 × 10²–42 × 10³) while for females of CBP it was 1:520 transfusions (CI 250–1700). The latter was dominated by HDFN risk, which would be expected to occur once every 5.7 years (CI 2.6–22.5). We estimated that a survival benefit of ≥1% using LTOWB would result in more life‐years gained than lost if D‐positive units were transfused exclusively. These risks would be lower, if D‐positive blood were only transfused when D‐negative units are unavailable.

Conclusion

These data suggest that the risk of transfusing RhD‐positive blood is low in the prehospital setting and must be balanced against its potential benefits.

THOR-AABB Working Party Recommendations for a Prehospital Blood Product Transfusion Program

The evidence for the lifesaving benefits of prehospital transfusions is increasing. As such, emergency medical services (EMS) might increasingly become interested in providing this important intervention. While a few EMS and air medical agencies have been providing exclusively red blood cell (RBC) transfusions to their patients for many years, transfusing plasma in addition to the RBCs, or simply using low titer group O whole blood (LTOWB) in place of two separate components, will be a novel experience for many services. The recommendations presented in this document were created by the Trauma, Hemostasis and Oxygenation Research (THOR)-AABB (formerly known as the American Association of Blood Banks) Working Party, and they are intended to provide a framework for implementing prehospital blood transfusion programs in line with the best available evidence. These recommendations cover all aspects of such a program including storing, transporting, and transfusing blood products in the prehospital phase of hemorrhagic resuscitation.

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.

Hemostatic Resuscitation in Children

Trauma is a major source of morbidity and mortality for children worldwide; life-threatening hemorrhage is a primary cause of preventable death. Essential interventions in children with life-threatening hemorrhage include hemostatic resuscitation and mechanical control of bleeding. Herein we review pediatric hemostatic resuscitation, a strategy that addresses both hemorrhagic shock and the coagulopathic complications described in patients with major hemorrhage. Some components of hemostatic resuscitation may include: early and aggressive resuscitation with blood products, minimizing crystalloid and hemodilution, antifibrinolytic adjuncts such as tranexamic acid, and the novel use of low-titer group O whole-blood (LTOWB) transfusion in injured children. The following selection of important publications address the current state of hemostatic resuscitation strategies in pediatric trauma patients as well as the remaining knowledge gaps and areas for further research.

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.

Risk of ABO-Incompatible Plasma From Non-ABO-Identical Components

The last several decades have seen significant changes in the approach to resuscitation of bleeding patients. These include the adoption of ABO-incompatible plasma transfusion in the form of group A plasma and/or low titer group O whole blood for trauma patients of unknown ABO group. Studies to date have examined the impact of these practices on patient outcomes and clinical markers of hemolysis in recipients of ABO-incompatible plasma compared to those for whom the plasma is ABO-compatible. Risk for increased mortality and/or overt hemolysis appear to be low among recipients of ABO-incompatible plasma; however, nearly all of studies are retrospective and most have focused only on adult trauma patients so results may not be generalizable to other bleeding patients. Work continues to evaluate the role of various titer thresholds in decreasing hemolytic risk and opportunities remain to improve our understanding of anti-A and anti-B antibody interactions with complement/endothelium and identify strategies to minimize risk.

The rebirth of the cool: a narrative review of the clinical outcomes of cold stored low titer group O whole blood recipients compared to conventional component recipients in trauma

There has been renewed interest in the use of low titer group O whole blood (LTOWB) for the resuscitation of civilian casualties. LTOWB offers several advantages over conventional components such as providing balanced resuscitation in one bag that contains less additive/preservative solution than an equivalent volume of conventional components, is easier and faster to transfuse than multiple components, avoids blood product ratio confusion, contains cold stored platelets, and reduces donor exposures. The resurgence in its use in the resuscitation of civilian trauma patients has led to the publication of an increasing number of studies on its use, primarily amongst adult recipients but also in pediatric patients. These studies have indicated that hemolysis does not occur amongst adult and pediatric non-group O recipients of a modest quantity of LTOWB. The published studies to date on mortality have shown conflicting results with some demonstrating a reduction following LTOWB transfusion while most others have not shown a reduction; there have not been any studies to date that have found significantly increased overall mortality amongst LTOWB recipients. Similarly, when other clinical outcomes, such as venous thromboembolism, sepsis, hospital or intensive care unit lengths of stay are evaluated, LTOWB recipients have not demonstrated worse outcomes compared to conventional component recipients. While definitive proof of the trends in these morbidity and mortality outcomes awaits confirmation in randomized controlled trials, the evidence to date indicates the safety of transfusing LTOWB to injured civilians.

Survey to inform trial of low-titer group O whole-blood compared to conventional blood components for children with severe traumatic bleeding

BACKGROUND

Low-titer group O whole-blood (LTOWB) is being used for children with life-threatening traumatic bleeding. A survey was conducted to determine current LTOWB utilization and interest in participation in a randomized control trial (RCT) of LTOWB versus standard blood component transfusion in this population.

STUDY DESIGN AND METHODS

Transfusion medicine (TM) directors and pediatric trauma directors at 36 US children's hospitals were surveyed by e-mail in June 2020. Hospitals were selected by participation in the Massive Transfusion Epidemiology and Outcomes in Children Study or being among the largest 30 children's hospitals by bed capacity per the Becker Hospital Review.

RESULTS

The response rate was 83.3% (30/36) from TM directors and 88.9% (32/36) from trauma directors. The median of massive transfusion protocol activations for traumatic bleeding was reported as 12 (IQR 5.8-20) per year by TM directors. LTOWB was used by 18.8% (6/32) of trauma directors. Survey responses indicate that 86.7% (26/30) of TM directors and 90.6% (29/32) of trauma directors either moderately or strongly agree that a LTOWB RCT is important to perform. About 83.3% (25/30) of TM directors and 93.8% (30/32) of trauma directors were willing to participate in the proposed trial. About 80% (24/30) of TM directors and 71.9% (23/32) of trauma directors would transfuse RhD+ LTOWB to male children, but fewer would transfuse Rh + LTOWB to females [20% (6/30) TM directors and 37.5% (12/32) of trauma directors].

CONCLUSIONS

A majority of respondents supported an RCT comparing LTOWB to component therapy in children with severe traumatic bleeding.

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.

Survey of group A plasma and low-titer group O whole blood use in trauma resuscitation at adult civilian level 1 trauma centers in the US

BACKGROUND

Recently revisited products like low-titer group O whole blood (LTOWB) and novel applications of group A as a universal donor of plasma are being used for trauma resuscitation. A survey of American Level 1 trauma centers was performed to elucidate the extent to which these products are currently employed.

METHODS

A survey was written that probed into the current use of blood products in trauma resuscitation with specific emphasis on LTOWB and group A plasma. A list of adult civilian Level 1 trauma centers in the continental USA was obtained from two public surgery and trauma focused websites. An email was then sent to each center's transfusion service medical director or laboratory manager providing them with a link to the online survey.

RESULTS

Responses were received from 103/187 (55%) adult civilian Level 1 trauma centers. For the resuscitation of trauma patients, group A plasma was used at 94/103 (91%) centers, while LTOWB was used at 43/103 (42%) centers. There were 39/103 (38%) centers that used both products. At 62/94 (66%) of the centers that used group A plasma, there was no limit on the number of units that could be administered, while an unlimited number of LTOWB units could be used at 5/43 (12%) of the centers that used LTOWB. RhD-positive LTOWB could be transfused to RhD-negative or RhD-type unknown females of childbearing potential at 22/43 (51%) of centers.

CONCLUSION

The use of group A plasma and LTOWB in trauma is increasing at American Level 1 trauma centers.

Effectiveness and safety of whole blood compared to balanced blood components in resuscitation of hemorrhaging trauma patients - A systematic review

INTRODUCTION

Hemorrhage is a leading cause of death among trauma patients, and is the most common cause of preventable death after trauma. Since the advent of blood component fractioning, most patients receive blood components rather than whole blood (WB). WB contains all of the individual blood components and has the advantages of simplifying resuscitation logistics, providing physiological ratios of components, reducing preservative volumes and allowing transfusion of younger red blood cells (RBC). Successful experience with fresh whole blood (FWB) by the US military is well documented. In the civilian setting, transfusion of cold-stored low titer type O whole blood (LTOWB) was shown to be safe. Reports of WB are limited by small numbers and low transfusion volumes.

STUDY DESIGN

We conducted a systematic review of the available published studies, comparing efficacy and safety of resuscitation with WB to resuscitation with blood components, in hemorrhaging trauma patients, using MEDLINE, EMBASE and ISI Web of Science. The main outcomes of interest were 24 hour and 30-day survival, blood product utilization and adverse events. Two reviewers independently abstracted the studies and assessed for bias. Sub-group analyses were pre-planned on the FWB and LTOWB groups separately.

RESULTS

Out of 126 references identified through our search strategy, five studies met the inclusion criteria. Only one study of FWB showed a significant benefit on 24 hour and 30-day survival. Other studies of both FWB and LTOWB showed no statistically significant difference in survival. There is an apparent benefit in blood product utilization with the use of WB across most studies. There were no reports of transfusion related reactions, however there was an increase in the organ failure rates in the FWB groups.

CONCLUSIONS

WB was not associated with a significant survival benefit or reduced blood product utilization. Nonetheless, it seems that the use of LTOWB is safe and might carry a significant logistic benefit. The quality of the existing data is poor and further high quality studies are required.

Hemostatic defects in massive transfusion: an update and treatment recommendations

INTRODUCTION

Acute hemorrhage is a global healthcare issue, and remains the leading preventable cause of death in trauma. Acute severe hemorrhage can be related to traumatic, peripartum, gastrointestinal, and procedural causes. Hemostatic defects occur early in patients requiring massive transfusion. Early recognition and treatment of hemorrhage and hemostatic defects are required to save lives and to achieve optimal patient outcomes.

AREAS COVERED

This review discusses current evidence and trials aimed at identifying the optimal treatment for hemostatic defects in hemorrhage and massive transfusion. Literature search included PubMed and Embase.

EXPERT OPINION

Patients with acute hemorrhage requiring massive transfusion commonly develop coagulopathy due to specific hemostatic defects, and accurate diagnosis and prompt correction are required for definitive hemorrhage control. Damage control resuscitation and massive transfusion protocols are optimal initial treatment strategies, followed by goal-directed individualized resuscitation using real-time coagulation monitoring. Distinct phenotypes exist in trauma-induced coagulopathy, including 'Bleeding' or 'Thrombotic' phenotypes, and hyperfibrinolysis vs. fibrinolysis shutdown. The trauma 'lethal triad' (hypothermia, coagulopathy, acidosis) has been updated to the 'lethal diamond' (including hypocalcemia). A number of controversies in optimal management exist, including whole blood vs. component therapy, use of factor concentrates vs. blood products, optimal use of tranexamic acid, and prehospital plasma and tranexamic acid administration.

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.

NATO and evidence-based military and disaster medicine: case for Vigorous Warrior Live Exercise Series

The North Atlantic Treaty Organization (NATO) is the premier and only security alliance uniting 30 countries and growing with many partner states in the provision of collective security and against threats posed by conflict and natural disasters. Security of countries and communities is increasingly threatened by a broad spectrum of unconventional types of war and disease threats - from hybrid and asymmetric to multi-domain and peer-to-peer/near-peer conflict. The NATO Centre of Excellence for Military Medicine (MILMED COE) is the centre of gravity for medical best practices and promotion of medical doctrine across the NATO alliance. Disaster medicine is multidisciplinary and in NATO, multinational, requiring best practices that are driven by data and evidence to prevent death on the battlefield and prepare for future conflicts. "Vigorous Warrior" is a live military and disaster medicine exercise series using both civilian and military actors across all sectors of health focused on health security and identifying lessons learned to ready the alliance for future threats. In this brief report, we make the case that the Vigorous Warrior exercise exposes gaps, highlights challenges and generates an evidence base to make NATO military medicine systems more robust, more efficient and in provision of best medical practices. We specifically argue that clinical data capture must be duplicated and continuous across the alliance to ensure evidence-based medicine stays current in NATO military medical doctrine.

Blood component separation of pathogen-reduced whole blood by the PRP method produces acceptable red cells but platelet yields and function are diminished

BACKGROUND

This study evaluated blood components processed by the platelet rich plasma (PRP) method from fresh whole blood (FWB) treated with a pathogen reduction technology (PRT). The effects of storage temperature on PRT treated platelet concentrates (PCs) were also examined.

STUDY DESIGN AND METHODS

PRT was performed using riboflavin and ultraviolet light on FWB in citrate phosphate dextrose anticoagulant. Following PRT, red blood cells (RBCs), PCs, and plasma for fresh frozen plasma (FFP), were isolated by sequential centrifugation. RBCs were stored at 4°C, FFP at -80°C, and PC at 22°C or at 4°C. Components were assayed throughout their storage times for blood gases, chemistry and CBC, hemostatic function as well as platelet (PLT) and RBC integrity.

RESULTS

Component processing following PRT resulted in a significant drop in platelet recovery. Most PRT-PC bags fell below AABB guidelines for platelet count. PRT-PC also showed a decrease in clot strength and decreased aggregometry response. Platelet caspases were activated by PRT. Storage at 4°C improved platelet function. In PRT-FFP, prothrombin time and partial thromboplastin time (PT and aPTT) were prolonged; factors V, VII, VIII, and XI, protein C, and fibrinogen were significantly decreased. Free hemoglobin was elevated two-fold in PRT-RBC.

CONCLUSION

Blood components isolated by the PRP method from PRT-treated WB result in a high percentage of PC that fail to meet AABB guidelines. FFP also shows diminished coagulation capacity. However, PRT-RBC are comparable to control-RBC. PRT-WB retains acceptable hemostatic function but alternatives to the PRP method of component separation may be more suitable.

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.

Whole blood for postpartum hemorrhage: early experience at two institutions

BACKGROUND

Death from postpartum hemorrhage (PPH) remains a significant preventable problem worldwide. Cold-stored, low-titer, type-O whole blood (LTOWB) is increasingly being used for resuscitation of injured patients, but it is uncommon in PPH patients, and it is unclear what its role may be in this population.

STUDY DESIGN AND METHODS

Brief report of the early experience of WB use for PPH in two institutions, one university hospital and one private hospital.

RESULTS

Different approaches have been implemented at the two institutions, one designed for emergency release, uncrossmatched transfusion of LTOWB as part of a massive transfusion protocol (MTP) and one for high-risk obstetric patients with known placental abnormalities. A total of 7 PPH patients have received a total of 17 units of LTOWB between the two institutions. No severe adverse transfusion reactions were observed clinically in either institution and the clinical outcomes were favorable in all cases.

CONCLUSION

In our early experience, LTOWB can be implemented for two different PPH clinical scenarios. Larger studies are needed to compare outcomes between LTOWB and traditional component resuscitation strategies.

Opportunities for standardization of cold stored, low-titre group O WB products

Interest in the use of cold-stored low-titre, group O whole blood (LTO-WB) in civilian trauma medicine has motivated regional and national blood services to explore the operational implications of providing this product to their hospital customers. While simpler to produce, store and administer than conventional blood components, LTO-WB is only distributed by a limited number of civilian blood services to date. To improve the availability of LTO-WB, there are still a number of clinical and basic research challenges that need to be addressed including 1. Standardization of the methods and definitions for what constitutes "low-titre" whole blood; 2. Updating regulatory standards for the in vitro quality of cold stored whole blood; 3. Development of standards for the post-storage component separation of red blood cells from cold stored whole blood; and 4. Optimization of the logistics for collection and distribution of cold stored whole blood in regional and national blood systems. The main objective of this concise overview is to highlight the opportunities for future research and product development efforts that will improve the availability of standardised LTO-WB products in emergency cases to the benefit of all concerned.

The History of Fluid Resuscitation for Bleeding

Damage control resuscitation (DCR) is a bundle of care first described by Holcomb et al. that is aimed at reducing death from hemorrhage for patients with severe traumatic bleeding. DCR principles include compressible hemorrhage control; hypotensive resuscitation; rapid surgical control of bleeding; avoidance of the overuse of crystalloids and colloids, prevention or correction of acidosis, hypothermia, and hypocalcaemia; and hemostatic resuscitation (blood-based resuscitation). Remote damage control resuscitation (RDCR) is defined as the prehospital application of DCR concepts. The term RDCR was first published by Gerhardt and has been disseminated by the (Trauma Hemostasis and Oxygenation Research), or THOR Network. The history of DCR and RDCR starts well before the inception of the terms. The concepts behind the principles of DCR and RDCR stretch far back into the past. This chapter provides an outline of this history, but it is limited to the fluid resuscitation aspect of DCR/RDCR.

Contemporary Transfusion Science and Challenges

Health care professionals must understand the impact of blood product transfusions and transfusion therapy procedures to ensure high-quality patient care, positive outcomes, and wise use of resources in blood management programs. Understanding transfusions of blood and blood products is also important because of the number of treatments performed, which affects individual patients and health care system resources. This article reviews research findings to acquaint health care professionals with the most successful protocols for blood, blood product, and coagulation factor transfusions. Damage control resuscitation in bleeding trauma patients, protocols for patients without trauma who are undergoing surgical procedures that place them at risk for excessive bleeding, and protocols for patients with sepsis are addressed. Emerging research continues to help guide mass transfusion treatments (restrictive vs liberal, balanced, and goal-directed treatment). Although available study results provide some guidance, questions remain. Additional research by health care professionals is needed.

Transfusion strategies in patients with cirrhosis

Bleeding related to portal hypertension and coagulopathy is a common complication in patients with cirrhosis. Complications and management of bleeding is a significant source of healthcare cost and utilization, as well as morbidity and mortality. Due to the scarcity of evidence surrounding transfusion strategies and hemostatic interventions in patients with cirrhosis, there has been significant debate regarding the best practice. Emerging data suggest that evidence supporting transfusion of packed red blood cells to a hemoglobin threshold of 7-8 g/dL is strong. thrombopoietin (TPO) receptor agonists have shown promise in increasing platelet levels and reducing transfusions preprocedurally, although have not specifically been found to reduce bleeding risk. Data for viscoelastic testing (VET)-guided transfusions appear favorable for reducing blood transfusion requirements prior to minor procedures and during orthotopic liver transplantation. Hemostatic agents such as recombinant factor VIIa, prothrombin complex concentrates, and tranexamic acid have been examined but their role in cirrhotic patients is unclear. Other areas of growing interest include balanced ratio and whole blood transfusion. In the following manuscript, we summarize the most up to date evidence for threshold-guided, VET-guided, balanced-ratio, and whole blood transfusions as well as the use of hemostatic agents in cirrhotic patients to provide practice guidance to clinicians.

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.

Lifeline for the front lines: blood products to support the warfighter

BACKGROUND

Hemorrhage is the leading cause of death on the battlefield. Damage control resuscitation guidelines in the US military recommend whole blood as the preferred resuscitation product. The Armed Services Blood Program (ASBP) has initiated low-titer group O whole blood (LTOWB) production and predeployment donor screening to make whole blood more available to military forces.

STUDY DESIGN AND METHODS

ASBP donor centers updated procedures and labeling for LTOWB production. Donors are screened according to US Food and Drug Administration regulations and standard operating procedures. Group O donors are tested for anti-A and anti-B titer levels. Additionally, military personnel notified for pending deployment coordinate with their local ASBP donor center to complete whole blood donor prescreening. The process consists of completing a donor history questionnaire, processing of blood samples for blood group and infectious disease testing, and titer determination for group O personnel.

RESULTS

Since March 2016, 7940 LTOWB units have been manufactured at ASBP donor centers and shipped in support of combat operations. Additionally, ASBP donor centers have screened several thousand service members before deployment. From these screenings, the donor low titer rate was 68% and infectious disease reactive test rate was extremely low (≤0.004).

CONCLUSION

Whole blood is now the preferred blood product for resuscitation of combat trauma patients. The ASBP partnered with combat forces to screen personnel before deployment. Additionally, LTOWB is manufactured and shipped in support of combat operations. These efforts are expanding the availability of LTOWB for the warfighter.

Give the trauma patient what they bleed, when and where they need it: establishing a comprehensive regional system of resuscitation based on patient need utilizing cold-stored, low-titer O+ whole blood

BACKGROUND

Despite countless advancements in trauma care a survivability gap still exists in the prehospital setting. Military studies clearly identify hemorrhage as the leading cause of potentially survivable prehospital death. Shifting resuscitation from the hospital to the point of injury has shown great promise in decreasing mortality among the severely injured.

MATERIALS AND METHODS

Our regional trauma network (Southwest Texas Regional Advisory Council) developed and implemented a multiphased approach toward facilitating remote damage control resuscitation. This approach required placing low-titer O+ whole blood (LTO+ WB) at helicopter emergency medical service bases, transitioning hospital-based trauma resuscitation from component therapy to the use of whole blood, modifying select ground-based units to carry and administer whole blood at the scene of an accident, and altering the practices of our blood bank to support our new initiative. In addition, we had to provide information and training to an entire large urban emergency medical system regarding changes in policy.

RESULTS

Through a thorough, structured program we were able to successfully implement point-of-injury resuscitation with LTO+ WB. Preliminary evaluation of our first 25 patients has shown a marked decrease in mortality compared to our historic rate using component therapy or crystalloid solutions. Additionally, we have had zero transfusion reactions or seroconversions.

CONCLUSION

Transfusion at the scene within minutes of injury has the potential to save lives. As our utilization expands to our outlying network we expect to see a continued decrease in mortality among significantly injured trauma patients.

Effects of whole blood leukoreduction on platelet function and hemostatic parameters

AIMS/OBJECTIVES

The aim of this study was to evaluate the hemostatic consequences of whole blood leukoreduction (LR).

BACKGROUND

Whole blood is being used for trauma resuscitation in the military, and an increasing number of civilian trauma centres across the nation. The benefits of LR, such as decreased infectious and transfusion-related complications, are well established, but the effects on hemostatic parameters remain a concern.

METHODS

Twenty-four units of whole blood were assigned to one of the four groups: non-leukoreduced (NLR), leukoreduced at 1 h and a height of 33 in. (LR-1), leukoreduced at 4 h and a height of 33 in. (LR-4(33)), or leukoreduced at 4 h and a height of 28 in. (LR-4(28)). Viscoelastic parameters, platelet aggregation, cell counts, physiological parameters and thrombin potential were evaluated immediately before and after LR, and on days 1, 7, 14 and 21 following LR.

RESULTS

The viscoelastic parameters and thrombin generation potential were unchanged between the groups. Platelet aggregation was reduced in the LR-1 group compared with NLR after 7 days. The LR-4(28) group also showed a trend of reduced platelet aggregation compared with NLR. Aggregation in LR-4(33) was similar to NLR throughout the storage time. Physiological and electrolyte changes over the whole blood storage period were not affected by LR.

CONCLUSION

Our study shows that whole blood can be LR at 4 h after collection and a height of 33 in. while maintaining platelet count and without altering platelet function and hemostatic performance.