Large volume transfusion with whole blood is safe compared with component therapy

Association between whole blood ratio and risk of mortality in massively transfused trauma patients: retrospective cohort study

BACKGROUND

Although whole blood (WB) transfusion was reported to improve survival in trauma patients with hemorrhagic shock, little is known whether a higher proportion of WB is associated with an improved survival. This study aimed to evaluate the association between whole blood ratio (WBR) and the risk of mortality in trauma patients requiring massive blood transfusion.

METHODS

We performed a retrospective cohort study from the ACS-TQIP between 2020 and 2021. Patients were aged ≥ 18 years and received WB within 4 h of hospital arrival as a part of massive blood transfusion. Study patients were categorized into four groups based on the quartiles of WBR. Primary outcome was 24-h mortality and secondary outcome was 30-day mortality. Multivariable logistic regression analysis, fitted with generalized estimating equations, was performed to adjust for confounding factors and accounted for within-hospital clustering.

RESULTS

A total of 4087 patients were eligible for analysis. The median age was 37 years (interquartile range [IQR]: 27-53 years), and 85.0% of patients were male. The median number of WB transfusions was 2.3 units (IQR 2.0-4.0 units), and the total transfusion volume was 4940 ml (IQR 3350-8504). When compared to the lowest WBR quartile, the highest WBR quartile had lower adjusted 24-h mortality (adjusted odds ratio [AOR]: 0.61, 95% confidence interval [CI]: 0.46-0.81) and 30-day mortality (AOR 0.58; 95% CI 0.45-0.75).

CONCLUSION

The probability of mortality consistently decreased with higher WBR in trauma patients requiring massive blood transfusion.

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.

The first two years of the use of low titer group O whole blood during French Military overseas operations: A retrospective study

BACKGROUND

On the battlefield, hemorrhage is the main cause of potentially preventable death. To reduce mortality due to hemorrhagic injuries, the French Military Medical Service (FMMS) has deployed low titer group O whole blood (LTOWB) since June 2021 during operation BARKHANE in the Sahel-Saharan strip. Questions persist regarding the circumstances under which the FMMS employs LTOWB during overseas operations.

STUDY DESIGN

We performed a retrospective analysis of all LTOWB transfused by the FMMS during overseas operations in the Sahel-Saharan strip between June 1, 2021, and June 1, 2023. Information was collected from battlefield forward transfusion sheets.

RESULTS

Over the 2-year study period, 40 units of LTOWB were transfused into 25 patients. Of the 25 patients, 18 were combat casualties and seven were transfused for non-trauma surgery. Of the 40 units of LTOWB transfused, 22 were provided during Role 2 care, 11 during tactical medical evacuation (MEDEVAC), and seven in light and mobile surgical units. Among combat casualties, LTOWB was the first blood product transfused in 13 patients. In combat casualties, 6 h post-trauma, the median ratio of plasma: red blood cells (RBCs) was 1.5, and the median equivalent platelet concentrate (PC) transfused was 0.17. No immediate adverse events related to LTOWB transfusion were reported.

CONCLUSION

LTOWB is transfused by the FMMS during overseas operations from the tactical MEDEVAC until Role 2 care. Deployment of LTOWB by the FMMS enables an early high-ratio plasma/RBC transfusion and an early platelet transfusion for combat casualties.

Use of Low-Titer O-Positive Whole Blood in Female Trauma Patients: A Literature Review, Qualitative Multidisciplinary Analysis of Risk/Benefit, and Guidelines for Its Use as a Universal Product in Hemorrhagic Shock

BACKGROUND

Whole blood transfusion is associated with benefits including improved survival, coagulopathy, and decreased transfusion requirements. The majority of whole blood transfusion is in the form of low-titer O-positive whole blood (LTOWB). Practice at many trauma centers withholds the use of LTOWB in women of childbearing potential due to concerns of alloimmunization. The purpose of this article is to review the evidence for LTOWB transfusion in female trauma patients and generate guidelines for its application.

STUDY DESIGN

Literature and evidence for LTOWB transfusion in hemorrhagic shock are reviewed. The rates of alloimmunization and subsequent obstetrical outcomes are compared to the reported outcomes of LTOWB vs other resuscitation media. Literature regarding patient experiences and preferences in regards to the risk of alloimmunization is compared to current trauma practices.

RESULTS

LTOWB has shown improved outcomes in both military and civilian settings. The overall risk of alloimmunization for Rhesus factor (Rh) - female patients in hemorrhagic shock exposed to Rh + blood is low (3% to 20%). Fetal outcomes in Rh-sensitized patients are excellent compared to historical standards, and treatment options continue to expand. The majority of female patients surveyed on the risk of alloimmunization favor receiving Rh + blood products to improve trauma outcomes. Obstetrical transfusion practices have incorporated LTOWB with excellent results.

CONCLUSIONS

The use of whole blood resuscitation in trauma is associated with benefits in the resuscitation of severely injured patients. The rate at which severely injured, Rh-negative patients develop anti-D antibodies is low. Treatments for alloimmunized pregnancies have advanced, with excellent results. Fears of alloimmunization in female patients are likely overstated and may not warrant the withholding of whole blood resuscitation. The benefits of whole blood resuscitation likely outweigh the risks of alloimmunization.

Damage Control Resuscitation in Traumatic Hemorrhage: It Is More Than Fixing the Holes and Filling the Tank

Damage control resuscitation is the foundation of hemorrhagic shock management and includes early administration of plasma, tranexamic acid, and limited crystalloid-containing products.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Whole blood transfusion in the treatment of acute hemorrhage, a systematic review and meta-analysis

BACKGROUND

Whole blood (WB) transfusion received renewed interest after recent armed conflicts. The effectiveness as compared with blood component transfusion (BCT) is, however, still topic of debate. Therefore, this study investigated the effect of WB ± BCT as compared with BCT transfusion on survival in trauma patients with acute hemorrhage.

METHODS

Studies published up to January 16, 2023, including patients with traumatic hemorrhage comparing WB ± BCT and BCT were included in meta-analysis. Subanalyses were performed on the effectiveness of WB in the treatment of civilian or military trauma patients, patients with massive hemorrhage and on platelet (PLT)/red blood cell (RBC), plasma/RBC and WB/RBC ratios. Methodological quality of studies was interpreted using the Cochrane risk of bias tool. The study protocol was registered in PROSPERO under number CRD42022296900.

RESULTS

Random effect pooled odds ratio (OR) for 24 hours mortality in civilian and military patients treated with WB as compared with BCT was 0.72 (95% confidence interval [CI], 0.53-0.97). In subanalysis of studies conducted in civilian setting (n = 20), early (4 hours, 6 hours, and emergency department) and 24 hours mortality was lower in WB groups compared with BCT groups (OR, 0.65; 95% CI, 0.44-0.96 and OR, 0.71; 95% CI, 0.52-0.98). No difference in late mortality (28 days, 30 days, in-hospital) was found. In military settings (n = 7), there was no difference in early, 24 hours, or late mortality between groups. The WB groups received significant higher PLT/RBC ( p = 0.030) during early treatment and significant higher PLT/RBC and plasma/RBC ratios during 24 hours of treatment ( p = 0.031 and p = 0.007). The overall risk of bias in the majority of studies was judged as serious due to serious risk on confounding and selection bias, and unclear information regarding cointerventions.

CONCLUSION

Civilian trauma patients with acute traumatic hemorrhage treated with WB ± BCT as compared to BCT had lower odds on early and 24-hour mortality. In addition, WB transfusion resulted in higher PLT/RBC and plasma/RBC ratios.

LEVEL OF EVIDENCE

Systematic Review and Meta-Analysis; Level III.

Hypocalcemia in Trauma is Determined by the Number of Units Transfused, Not Whole Blood Versus Component Therapy

INTRODUCTION

Blood component resuscitation is associated with hypocalcemia (HC) (iCal <0.9 mmol/L) that contributes to coagulopathy and death in trauma patients. It is unknown whether or not whole blood (WB) resuscitation helps mitigate the risk of HC in trauma patients. We hypothesized that calcium homeostasis is maintained and mortality improved in patients who only receive WB.

MATERIALS AND METHODS

This is a retrospective review of all adult trauma patients who received WB from July 2018 to December 2020. Variables included transfusions, ionized calcium levels, and calcium replacement. Patients were characterized as follows based on blood products received: WB or WB with other blood components. Groups were compared with respect to HC, correction of HC, 24 h, and inpatient mortality.

RESULTS

Two hundred twenty-three patients received WB and met the inclusion criteria. 107 (48%) received WB only. HC occurred in 13% of patients who received more than one WB unit compared to 29% of WB and other blood component patients (P = 0.02). WB patients received less calcium replacement (median 250 mg versus 2000 mg, P < 0.01). HC and total units transfused within 4 h were associated with mortality in the adjusted model. HC significantly increased after 5 units of blood products were transfused, regardless of product type. WB was not protective against HC.

CONCLUSIONS

HC and failure to correct HC are significant risk factors for mortality in trauma. Resuscitations with WB only and WB in combination with other blood components are associated with HC especially when more than 5 units of any blood product are transfused. Calcium supplementation should be prioritized in any large volume transfusion, regardless of blood product type.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

High-dose radiation exposure of cold-stored whole blood does not affect hemostatic function

BACKGROUND

Whole blood (WB) transfusion is routinely used to resuscitate severely injured military trauma patients. Blood can be stored refrigerated while still maintaining reasonable function but is susceptible to environmental influences, including radiation exposure. Immune-compromised patients are transfused with irradiated blood to inactivate donor lymphocyte function (25 Gy per Association for the Advancement of Blood and Biotherapies [AARB] standard 5.7.3.2). However, there is limited information on function of WB exposed to high radiation doses.

OBJECTIVE

This study aimed to determine if stored irradiated WB still retains function. This will be important if the stored blood supply is exposed to radiation in a combat situation or mass casualty incident when the need for blood will be high.

METHODS

Whole blood collected from healthy donors was irradiated at 0, 25, or 75 Gy and stored at 4°C. Blood cell count, blood gas chemistry, thromboelastometry, platelet aggregation, and reactive oxygen species were measured before irradiation and at 1, 7, and 14 days of storage. Irradiated WB was compared with nonirradiated WB controls.

RESULTS

Irradiated WB stored for up to 14 days was not significantly different than nonirradiated WB in most of the parameters measured. Stored blood showed expected changes associated with functional decline at longer storage times, but irradiation did not hasten the decline. There was a significant change in potassium and sodium ion concentrations after irradiation, but the functional relevance is not clear.

CONCLUSION

High-dose irradiation had little effect on stored WB. Although there were changes in plasma sodium and potassium levels, there was little to no effect on hemostasis and blood cell viability. This suggests that stored blood subjected to a radiation event generating at least a dose of 75 Gy is still suitable for transfusion, which could be particularly important in the event of a mass casualty event where a large amount of blood is needed.

Management of Hemorrhagic Shock: Physiology Approach, Timing and Strategies

Hemorrhagic shock (HS) management is based on a timely, rapid, definitive source control of bleeding/s and on blood loss replacement. Stopping the hemorrhage from progressing from any named and visible vessel is the main stem fundamental praxis of efficacy and effectiveness and an essential, obligatory, life-saving step. Blood loss replacement serves the purpose of preventing ischemia/reperfusion toxemia and optimizing tissue oxygenation and microcirculation dynamics. The "physiological classification of HS" dictates the timely management and suits the 'titrated hypotensive resuscitation' tactics and the 'damage control surgery' strategy. In any hypotensive but not yet critical shock, the body's response to a fluid load test determines the cut-off point between compensation and progression between the time for adopting conservative treatment and preparing for surgery or rushing to the theater for rapid bleeding source control. Up to 20% of the total blood volume is given to refill the unstressed venous return volume. In any critical level of shock where, ab initio, the patient manifests signs indicating critical physiology and impending cardiac arrest or cardiovascular accident, the balance between the life-saving reflexes stretched to the maximum and the insufficient distal perfusion (blood, oxygen, and substrates) remains in a liable and delicate equilibrium, susceptible to any minimal change or interfering variable. In a cardiac arrest by exsanguination, the core of the physiological issue remains the rapid restoration of a sufficient venous return, allowing the heart to pump it back into systemic circulation either by open massage via sternotomy or anterolateral thoracotomy or spontaneously after aorta clamping in the chest or in the abdomen at the epigastrium under extracorporeal resuscitation and induced hypothermia. This is the only way to prevent ischemic damage to the brain and the heart. This is accomplishable rapidly and efficiently only by a direct approach, which is a crush laparotomy if the bleeding is coming from an abdominal +/- lower limb site or rapid sternotomy/anterolateral thoracotomy if the bleeding is coming from a chest +/- upper limbs site. Without first stopping the bleeding and refilling the heart, any further exercise is doomed to failure. Direct source control via laparotomy/thoracotomy, with the concomitant or soon following venous refilling, are the two essential, initial life-saving steps.

Transfusion management in the trauma patient

PURPOSE OF REVIEW

Transfusion of blood products is lifesaving in the trauma ICU. Intensivists must be familiar with contemporary literature to develop the optimal transfusion strategy for each patient.

RECENT FINDINGS

A balanced ratio of red-blood cells to plasma and platelets is associated with improved mortality and has therefore become the standard of care for resuscitation. There is a dose-dependent relationship between units of product transfused and infections. Liquid and freeze-dried plasma are alternatives to fresh frozen plasma that can be administered immediately and may improve coagulation parameters more rapidly, though higher quality research is needed. Trauma induced coagulopathy can occur despite a balanced transfusion, and administration of prothrombin complex concentrate and cryoprecipitate may have a role in preventing this. In addition to balanced ratios, viscoelastic guidance is being increasingly utilized to individualize component transfusion. Alternatively, whole blood can be used, which has become the standard in military practice and is gaining popularity at civilian centers.

SUMMARY

Hemorrhagic shock is the leading cause of death in trauma. Improved resuscitation strategy has been one of the most important contemporary advancements in trauma care and continues to be a key area of clinical research.

National analysis of whole blood and component versus component transfusions in civilian trauma patients who underwent a thoracotomy or laparotomy: Toward improving patient outcomes and quality of care

BACKGROUND

This study aimed to investigate the associations of whole blood and component versus component transfusions with in-hospital mortality, complication rates, intensive care unit length of stay, and packed red blood cells transfusion volumes in adult civilian trauma patients.

METHODS

We performed a retrospective cohort study of the American College of Surgeons Trauma Quality Program Participant Use File 2016 to 2019 dataset. Adult civilian trauma patients (aged >18 years) sustaining injuries of at least moderate severity who received whole blood and component or component within 4 hours of arrival and underwent thoracotomy or laparotomy were included. Multivariable regression analysis was used to compare outcomes between whole blood and component and component groups.

RESULTS

A total of 37,384 patients met eligibility criteria, of which 218 received whole blood and component and 37,166 received component. There was no significant difference in in-hospital mortality between whole blood and component and component groups for those who underwent thoracotomy (adjusted odds ratio = 0.408, P = .413) or laparotomy (adjusted odds ratio = 1.046, P = .857). Thoracotomy patients who received whole blood and component had no difference in 4-hour or 24-hour pack red blood cell volumes (3336 mL vs 3106 mL, P = .754; 3 658mL vs 3,636mL, P = .982), intensive care unit length of stay (10.68 days vs 8.63 days, P = .542), or complications rates compared to those who received component. Laparotomy patients who received whole blood and component had no difference in 4 hour or 24-hour packed red blood cell volumes (2,758 mL vs 2,721mL, P = .927; 3,538 mL vs 3,385 mL, P = .754), intensive care unit length of stay (11.78 days vs 9.90 days, P = .177), or complications rates compared to those who received component.

CONCLUSION

Study findings have indicated that a combined resuscitation with whole blood and component transfusion in adult civilian trauma patients is a viable alternative to component transfusion alone.

Prehospital Use of Whole Blood for Ill and Injured Patients During Critical Care Transport

OBJECTIVE

Hemodynamic instability and hemorrhagic shock are frequently encountered by emergency medical services providers managing ill and injured patients during critical care transport. Although many critical care transport services commonly transfuse crystalloids and/or packed red blood cells (PRBCs), the administration of whole blood (WB) in prehospital care is currently limited. WB contains PRBCs, plasma, and platelets in a physiologic ratio to aid in oxygen delivery to tissue as well as hemostasis. This study describes a single critical care transport program's experience using WB for critically ill and injured patients and reports important clinical and safety outcomes.

METHODS

This study was a retrospective review of patients who were transported by a single rotor wing-based critical care transport service to 1 of 2 tertiary care receiving hospitals within a single health system. Patients who were transported between November 1, 2018, and November 30, 2019, and who received at least 1 unit of low-titer group O WB during critical care transport were included. The primary outcomes of interest included 24-hour mortality and the total 24-hour transfusion requirement. The safety outcomes included transfusion reactions, acute lung injury, acute kidney injury, and the incidence of venous thromboembolism.

RESULTS

During the study period, there were 3,084 total patients transported by our critical care transport service. There were 71 patients who received prehospital WB, 64 of whom met the inclusion criteria. The top 3 indications for WB administration included blunt trauma (n = 27, 42.2%), gastrointestinal hemorrhage (n = 15, 23.4%), and penetrating trauma (n = 11, 17.2%). The median total number of blood components transfused within 24 hours was 4.0 (interquartile range, 2.0-9.5), and the overall 24-hour mortality rate was 21.9%.

CONCLUSIONS

The administration of WB by emergency medical services providers to critically ill and injured patients in the prehospital setting is feasible and is associated with low incidences of adverse events and transfusion reactions. Further research is needed to elucidate the benefits of WB relative to current prehospital standards of care.

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.

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).

Whole Blood Versus Conventional Blood Component Massive Transfusion Protocol Therapy in Civilian Trauma Patients

BACKGROUND

Military data demonstrating an improved survival rate with whole blood (WB) have led to a shift toward the use of WB in civilian trauma. The purpose of this study is to compare a low-titer group O WB (LTOWB) massive transfusion protocol (MTP) to conventional blood component therapy (BCT) MTP in civilian trauma patients.

METHODS

Trauma patients 15 years or older who had MTP activations from February 2019 to December 2020 were included. Patients with a LTOWB MTP activation were compared to BCT MTP patients from a historic cohort.

RESULTS

299 patients were identified, 169 received LTOWB and 130 received BCT. There were no differences in age, gender, or injury type. The Injury Severity Score was higher in the BCT group (27 vs 25, P = .006). The LTOWB group had a longer transport time (33 min vs 26 min, P < .001) and a lower arrival temperature (35.8 vs 36.1, P < .001). Other hemodynamic parameters were similar between the groups. The LTOWB group had a lower in-hospital mortality rate compared to the BCT group (19.5% vs 30.0%, P = .035). There were no differences in total transfusion volumes at 4 hours and 24 hours. No differences were seen in transfusion reactions or hospital complications. Multivariable logistic regression identified ISS, age, and 24-hour transfusion volume as predictors of mortality.

DISCUSSION

Resuscitating severely injured trauma patient with LTOWB is safe and may be associated with an improved survival.

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.

Safety and efficacy of low-titer O whole blood resuscitation in a civilian level I trauma center

BACKGROUND

Military experience has shown low-titer O whole blood (LTOWB) to be safe and beneficial in the resuscitation of hemorrhaging trauma patients. However, few civilian centers use LTOWB for trauma resuscitation. We evaluated the early experience and safety of a LTOWB program at a level 1 civilian trauma center.

METHODS

We retrospectively reviewed our trauma registry from January 2018 to June 2020 for patients admitted in shock (defined as ≥1 of the following: heart rate, >120 beats per minute; systolic blood pressure, <90 mm Hg; or shock index, >0.9) who received blood products within 24 hours. Patients were grouped by resuscitation provided: LTOWB (group 1), component therapy (CT; group 2), and LTOWB-CT (group 3). Safety, outcomes, and variables associated with LTOWB transfusion and mortality were analyzed.

RESULTS

216 patients were included: 34 in Group 1, 95 in Group 2, and 87 in Group 3. Patientsreceiving LTOWB were more commonly male (p<0.001) and had a penetrating injury (p=0.005). Groups 1 and 3 had higher median ISS scores compared to Group 2 (19 and 20 vs 17; p=0.01). Group 3 received more median units of blood product in the first 4h (p<0.001) and in the first 24h (p<0.001). There was no difference between groups in 24h mortality or transfusion-related complications (all p>0.05). Arrival ED SBP was associated with LTOWB transfusion (odds ratio [OR] 0.98, 95% confidence interval [CI] 0.95-1.00, p=0.03). ED lactate was independently associated with 24h mortality. (OR 1.27, CI 1.02-1.58, p=0.03). LTOWB transfusion was not associated with mortality (p=0.49). Abstract.

CONCLUSION

Severely injured patients received LTOWB-CT and more overall product units but had similar 24 h mortality when compared with the LTOWB or CT groups. No increase in transfusion-related complications was seen after LTOWB transfusion. Low-titer O whole blood should be strongly considered in the resuscitation of trauma patients at civilian centers.

LEVEL OF EVIDENCE

Retrospective, therapeutic, level IV.

Injured recipients of low-titer group O whole blood have similar clinical outcomes compared to recipients of conventional component therapy: A single-center, retrospective study

INTRODUCTION

Low-titer group O whole blood (LTOWB) is being increasingly transfused to injured patients. This study evaluated a range of clinical outcomes to determine if receipt of LTOWB predisposed recipients to worse outcomes compared to recipients of conventional component therapy (CCT).

METHODS

A retrospective analysis of trauma patients who received at least 3 units of LTOWB (LTOWB group) versus those that received at least 3 units of RBCs, 1 unit of plasma and 1 unit of platelets but no LTOWB (CCT group) during the first 24 h of their admission was performed. Causal treatment effects were explored using propensity score matching (PSM) and coarsened exact matching (CEM). Important clinical outcomes were evaluated.

RESULTS

There were 165 CCT and 155 LTOWB recipients eligible for matching. PSM and CEM reduced covariate imbalances between the CCT and LTOWB groups, with the exception that males remained over-represented in the LTOWB group due to the hospital's former resuscitation policy of not administering RhD-positive LTOWB to females <50. In both of the matched analyses, the LTOWB group received a median of 4 LTOWB units. There were no significant differences in 6-, 24-h mortality or 30-day mortality between groups, nor were there differences in the frequency of other clinical outcomes such as acute kidney injury, sepsis, venous/arterial thromboembolism; delta MODS was lower for the LTOWB recipients in the exact match group.

CONCLUSION

In both matched analyses, administration of a median of four LTOWB units did not result in a different frequency of major clinical outcomes including mortality.

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.

Single Institution Trial Comparing Whole Blood vs Balanced Component Therapy: 50 Years Later

BACKGROUND

Early close ratio transfusion with balanced component therapy (BCT) has been associated with improved outcomes in patients with severe hemorrhage; however, this modality is not comparable with whole blood (WB) constituents. We compared use of BCT vs WB to determine if one yielded superior outcomes in patients with severe hemorrhage. We hypothesized that WB would lead to reduced in-hospital mortality and blood product volume if given in the first 24 hours of admission.

STUDY DESIGN

This was a 1-year, single institution, prospective, observational study comparing BCT with WB in adult (18+y) trauma patients with active hemorrhage who required blood transfusion upon arrival at the emergency department. Primary endpoint was in-hospital mortality. Secondary endpoints included 24-hour transfusion volumes, in-hospital clinical outcomes, and complications.

RESULTS

A total of 253 patients were included; 71.1% received BCT and 29.9% WB. The WB cohort had significantly more penetrating trauma (64.4% vs 48.9%; p = 0.03) and higher Shock Index (1.12 vs 0.92; p = 0.04). WB patients received significantly fewer units of packed red blood cells (PRBCs) (p < 0.001) and fresh frozen plasma (FFP) (p = 0.04), with a lower incidence of ARDS (p = 0.03) and fewer ventilator days (p = 0.03). Kaplan Meier survival analysis revealed no difference in survival between the 2 transfusion strategies (p = 0.80). When adjusted for various markers of injury severity and critical illness in Cox regression analysis, WB remained unassociated with mortality (hazard ratio 1.25; 95% CI 0.60-2.58; p = 0.55).

CONCLUSIONS

There was no difference in survival rates when comparing BCT with WB. In the WB group, the incidence of ARDS, duration of mechanical ventilation, massive transfusion protocol (MTP) activation, and transfusion volumes were significantly reduced. Further research should be directed at analyzing whether there is a true hemorrhage-related pathophysiologic benefit of WB when compared with BCT.

Massive transfusion protocol in adult trauma population

BACKGROUND

Acute blood loss in trauma requires quick identification and action to restore circulating volume and save the patient. Massive transfusion protocols (MTPs) have become standard at Trauma Centers, in order to rapidly deliver blood products to bleeding patients. This literature review presents current standards of transfusion ratios, as well as insights into adjuncts during massive transfusions.

METHODS

PubMED was searched for articles from 2005 to 2020 on MTPs, the article were assessed for single vs. multi-institutional, mechanism of injury, type of MTP, timing in which blood products should be administered, timing of delivery of blood products to trauma bay, pre-hospital treatment and adjuncts, and outcomes.

RESULTS

Eleven studies addressed transfusion ratios. Seven studies looked at timing of blood products. Nine studies addressed MTP pre-hospital treatment and adjuncts. Prior to 2015, studies supported the benefits of a balanced transfusion ratio, which was then confirmed by the PROPPR randomized controlled trial. The shorter the time to blood product delivery the better the outcomes. New advances in technology have allowed us to measure different patterns of coagulation, allowing more individualized approaches to the bleeding patient.

CONCLUSION

Current massive transfusion protocols should utilize between 1:1:1 and 1:1:2 ratios of the 3 main products; plasma, platelets, and red blood cells. Massive transfusion protocols are effective in decreasing mortality. Better resuscitation efforts were seen when blood products were readily available in the trauma bay when the patient arrived and the faster the replacement of blood, the better the outcomes.