Making whole blood for trauma available (again): the American Red Cross experience

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.

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.

Evaluating the Tactical Combat Casualty Care principles in civilian and military settings: systematic review, knowledge gap analysis and recommendations for future research

OBJECTIVES

The Tactical Combat Casualty Care (TCCC) guidelines detail resuscitation practices in prehospital and austere environments. We sought to review the content and quality of the current TCCC and civilian prehospital literature and characterize knowledge gaps to offer recommendations for future research.

METHODS

MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials were searched for studies assessing intervention techniques and devices used in civilian and military prehospital settings that could be applied to TCCC guidelines. Screening and data extraction were performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Quality appraisal was conducted using appropriate tools.

RESULTS

Ninety-two percent (n=57) of studies were observational. Most randomized trials had low risk of bias, whereas observational studies had higher risk of bias. Interventions of massive hemorrhage control (n=17) were wound dressings and tourniquets, suggesting effective hemodynamic control. Airway management interventions (n=7) had high success rates with improved outcomes. Interventions of respiratory management (n=12) reported low success with needle decompression. Studies assessing circulation (n=18) had higher quality of evidence and suggested improved outcomes with component hemostatic therapy. Hypothermia prevention interventions (n=2) were generally effective. Other studies identified assessed the use of extended focused assessment with sonography in trauma (n=3) and mixed interventions (n=2).

CONCLUSIONS

The evidence was largely non-randomized with heterogeneous populations, interventions, and outcomes, precluding robust conclusions in most subjects addressed in the review. Knowledge gaps identified included the use of blood products and concentrate of clotting factors in the prehospital setting.

LEVEL OF EVIDENCE

Systematic review, level III.

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.

Platelet aggregation in whole blood is not impaired by a platelet-sparing leukoreduction filter and instead depends upon the presence of leukocytes

BACKGROUND

Recent studies characterizing in vitro hemostatic properties of whole blood (WB) leukoreduced (LR) with a platelet-sparing filter have described subtle, if any, changes to viscoelastic clotting; however, reductions in platelet (PLT) content and impedance aggregometry (IA) responses have been noted. The effects of filtration of WB (i.e., filter-contact effects, reduction in platelet and leukocyte count) have not been rigorously investigated as to their individual impacts on platelet IA responses.

STUDY DESIGN AND METHODS

WB units from healthy donors were collected and characterized to assess the effects of platelet-sparing leukoreduction (LR) upon the in vitro hemostatic measures of platelet IA and thromboelastometry. Further characterization of platelet IA responses was carried out in WB samples to delineate the effects of platelet count and leukocyte presence/absence upon the response.

RESULTS

WB filtration reduced the platelet count and IA responses but had no impact on viscoelastic clotting measures in fresh WB. Experiments revealed that IA responses have a linear correlation with platelet count in both apheresis platelets and WB and that passage of platelets through the WB-LR filter has no impact upon the strength of this response. Further experiments in LR WB showed that addition of autologous leukocytes back to the platelets fully restored the platelet aggregation response to pre-filtration levels.

CONCLUSION

WB filtration results in platelet count reduction and leukocyte removal; however, platelet IA is not degraded by passage through the filter. Apparent declines in platelet IA responses can be fully attributed to the reduction in platelet count and the removal of leukocytes.

Conservation of Rh negative Low Titer O Whole Blood (LTOWB) and the need for a national conversation to define its use in trauma transfusion protocols

Low‐titer group O whole blood (LTOWB) use is growing steadily in the United States. Although the percentage of O negative LTOWB use by Red Cross hospitals has remained steady at ~23% over the last 2 years, this elevated use rate is twice that of O negative RBC components. Given the more restricted group O donor pool, this level of use will make it difficult to expand the use of this product. Evaluation of hospital practices regarding females of childbearing potential show significant variability with some hospitals transfusing O positive, with others choosing to restrict this population to O negative LTOWB or only O negative RBC component therapy. To ensure access of LTOWB to all patients who may benefit and to maintain sufficient supplies, we recommend developing standardized practice recommendations for its use.

The Bitter and the Sweet: Relationship of Lactate, Glucose, and Mortality After Severe Blunt Trauma

BACKGROUND

Hyperglycemia is associated with mortality after trauma; however, few studies have simultaneously investigated the association of depth of shock and acute hyperglycemia. We evaluated lactate, as a surrogate measure for depth of shock, and glucose levels on mortality following severe blunt trauma. We hypothesize that measurements of both lactate and glucose are associated with mortality when considered simultaneously.

METHODS

This is a retrospective cohort study at a single academic trauma center. Inclusion criteria are age 18-89 years, blunt trauma, injury severity score (ISS) ≥15, and transferred from the scene of injury. All serum blood glucose and lactate values were analyzed within the first 24 hours of admission. Multiple metrics of glucose and lactate were calculated: first glucose (Glucadm) and lactate (Lacadm) at hospital admission, mean 24-hour after hospital admission glucose (Gluc24-hMean) and lactate (Lac24-hMean), maximum 24-hour after hospital admission glucose (Gluc24-hMax) and lactate (Lac24-hMax), and time-weighted 24-hour after hospital admission glucose (Gluc24-hTW) and lactate (Lac24-hTW). Primary outcome was in-hospital mortality. Multivariable logistic regression modeling assessed the odds ratio (OR) of mortality, after adjusting for confounding variables.

RESULTS

A total of 1439 trauma patients were included. When metrics of both glucose and lactate were analyzed, after adjusting for age, ISS, and admission shock index, only lactate remained significantly associated with mortality: Lacadm (OR, 1.28; 95% confidence interval [CI], 1.13-1.44); Lac24-hMean (OR, 1.86; 95% CI, 1.52-2.28); Lac24-hMax (OR, 1.39; 95% CI, 1.23-1.56); and Lac24-hTW (OR, 1.86; 95% CI, 1.53-2.26).

CONCLUSIONS

Lactate is associated with mortality in severely injured blunt trauma patients, after adjusting for injury severity, age, and shock index. However, we did not find evidence for an association of glucose with mortality after adjusting for lactate.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

LEVEL OF EVIDENCE

Systematic/therapeutic, level 3.

Quality of Platelets in Stored Whole Blood

Transfusion of whole blood rather than blood components is gaining popularity. It is easy to use, with one transfusion product to administer rather than 3, and is held at one storage temperature. It only contains anticoagulant-preservative solution, while components contain various storage solutions, which in theory may induce dilution coagulopathy. In this review, the quality of platelets in stored whole blood is summarized. In cold-stored whole blood, the platelet count declines by 1% to 2% per day. The responsiveness to various agonists declines during the storage time, but this appears to have a limited impact on clotting time or on clot strength as measured with thromboelastography. Animal studies have confirmed that platelets from stored whole blood participate equally well in clot formation. The recovery of platelets in stored whole blood is acceptable during at least 15 days of storage. The survival of platelets after transfusion is only 1 day, but this is likely to be sufficient for the intended patient group requiring massive transfusions, as the platelets are rapidly consumed in the wound area. In addition to the logistic benefits, there are drawbacks, most importantly having a sufficiently large inventory with an acceptable outdating rate, particularly since massive transfusions are rare, while requiring a lot of whole blood. The positive experience of the United States military with whole blood transfusion is often brought forward for introduction in the civilian blood bank, but patients with trauma are only a small fraction of the civilian population requiring massive transfusions. It needs to be determined whether in the resourceful environment of the hospital, these patients benefit from whole blood transfusions. Optimization of whole blood storage, with focus on platelet quality, needs to be performed to allow extension of the storage time beyond 15 days to a point where the number of units in inventory and outdating can be balanced.

Optimizing blood bank resources when implementing a low-titer group O+ whole blood program: an in silico study

INTRODUCTION

Low-titer group O+ whole blood (LTOWB) is becoming commonly used in massive bleeding resuscitation, but the impact on blood center O+ RBCs has not been studied. This in silico model simulated a variety of different LTOWB production and utilization patterns.

METHODS

Collections and distributions data from a large blood collector were scaled to vary the total number of O+ red blood cell (RBC) collections, the O+ RBC collection: import ratio, and the O+ RBC apheresis: whole blood (WB) collection ratio. Daily LTOWB demand was determined by the daily number of LTOWB recipients, average number of LTOWB units transfused per patient, maximum number of LTOWB units a single patient can receive, and seasonality of LTOWB use. LTOWB program factors included the high-titer exclusion %, the LTOWB expiry, and whether LTOWB units were reclaimed as O+ RBC units on the date of expiry. Simulations using unique combinations of the above input parameters were performed.

RESULTS

For the 1,224,720 unique combinations of input parameters simulated, the average increase in the fraction of additional O+ RBC units required to meet hospital demand was only 0.02%. Higher daily LTOWB demand resulted in more LTOWB shortages. Increasing the minimum LTOWB inventory threshold reduced LTOWB shortages without increasing the number of required additional RBC units. LTOWB wastage was minimal but was lower with longer LTOWB shelf life or manufacture of RBC units from unused LTOWB on Day 14.

CONCLUSION

Implementing an LTOWB program does not have a major impact on the blood collectors' needs for additional RBC units to meet hospital demands.

Massive Transfusion Protocols for Pediatric Patients: Current Perspectives

In adults, the use of balanced resuscitation and study of massive transfusion protocols have led to improved outcomes for patients and continues to be refined. In children, massive transfusion protocols require further development and study to assess efficacy. Standardization is needed as transfusions and activation of protocols still rely on physician discretion in most pediatric settings. Further research is required to define the pediatric trauma population that will benefit, when to activate these protocols and how to use adjuncts such as tranexamic acid or factor VII in resuscitation. In addition, future implementation of technology such as hemoglobin-based oxygen carriers to increase survival should be studied further in this subset of patients.