Novel method for determining when a field-collected donor unit is sufficiently full

BACKGROUND

Whole blood (WB) collections can occur downrange for immediate administration. An important aspect of these collections is determining when the unit is sufficiently full. This project tested a novel method for determining when a field collection is complete.

METHODS

The amount of empty space at the top of WB units, destined to become LTOWB or separated into components, that were collected at blood centers or hospitals was measured by holding a WB unit off the ground and placing the top of a piece of string where the donor tubing entered the bag. The string was marked where it intersected the top of the column of blood in the bag and measured from the top. The WB units were also weighed.

RESULTS

A total of 15 different bags, two of which were measured in two different filling volumes, from 15 hospitals or blood centers were measured and weighed. The most commonly used blood bag, Terumo Imuflex SP, had a median string length of 9 mm (range: 2-24 mm) and weighed a median of 565.1 g (range: 524.8-636.7 g).

CONCLUSION

Pieces of string can be precut to the appropriate length depending on the type of bag before a mission where field WB collections might be required and a mark placed on the bag before the collection commences to indicate when the unit is full.

A review and analysis of outcomes in randomized clinical trials of plasma transfusion in patients with bleeding or for the prevention of bleeding: The BEST collaborative study

BACKGROUND

Previous systematic reviews have revealed an inconsistency of outcome definitions as a major barrier in providing evidence-based guidance for the use of plasma transfusion to prevent or treat bleeding. We reviewed and analyzed outcomes in randomized controlled trials (RCTs) to provide a methodology for describing and classifying outcomes.

STUDY DESIGN AND METHODS

RCTs involving transfusion of plasma published after 2000 were identified from a prior review (Yang 2012) and combined with an updated systematic literature search of multiple databases (July 1, 2011 to January 17, 2023). Inclusion of publications, data extraction, and risk of bias assessments were performed in duplicate. (PROSPERO registration number is: CRD42020158581).

RESULTS

In total, 5579 citations were identified in the new systematic search and 22 were included. Six additional trials were identified from the previous review, resulting in a total of 28 trials: 23 therapeutic and five prophylactic studies. An increasing number of studies in the setting of major bleeding such as in cardiovascular surgery and trauma were identified. Eighty-seven outcomes were reported with a mean of 11 (min-max. 4-32) per study. There was substantial variation in outcomes used with a preponderance of surrogate measures for clinical effect such as laboratory parameters and blood usage.

CONCLUSION

There is an expanding literature on plasma transfusion to inform guidelines. However, considerable heterogeneity of reported outcomes constrains comparisons. A core outcome set should be developed for plasma transfusion studies. Standardization of outcomes will motivate better study design, facilitate comparison, and improve clinical relevance for future trials of plasma transfusion.

The safety of ABO minor incompatible platelets transfusions using a rapid infuser

BACKGROUND

Administering platelets through a rapid infuser is proven to be safe. However, the clinical significance of infusing ABO-incompatible platelets with red blood cells (RBCs) in a rapid infuser remains unclear. There is a theoretical risk that isoagglutinin in the plasma of a platelet unit can interact with RBCs and induce hemolysis.

MATERIALS AND METHODS

Seven in vitro studies were performed including five cases (type A RBCs and type O platelets) and two controls (type A RBCs and platelets). Anti-A titers were measured in platelet units. An RBC unit and a platelet unit were mixed in the rapid infuser reservoir and incubated for 30 min. The primary outcome was the presence of hemolysis based on the following parameters: free hemoglobin concentration, hemolysis check, direct antiglobulin test (DAT), and direct agglutination.

RESULTS

The post-mix DAT was positive for IgG in all test samples (5/5), and weakly positive for complement in 3/5. The changes in free Hb in test cases between measured and calculated post-mix spanned -2.2 to +3.4 mg/dL. Post-mix hemolysis check was negative in 3/5 and slightly positive in 2/5 cases, with no significant differences compared to the control case. Anti-A titers ranged from 16 to 512 and were not associated with hemolysis. All samples were negative for direct agglutination.

CONCLUSION

Our study suggested that mixing ABO-incompatible platelets with RBCs in a rapid infuser does not induce in vitro hemolysis. These findings support the use of rapid infusers regardless of platelet compatibility in support of hemostatic resuscitation.

Hypocalcaemia upon arrival (HUA) in trauma patients who did and did not receive prehospital blood products: a systematic review and meta-analysis

PURPOSE

Hypocalcaemia upon arrival (HUA) to hospital is associated with morbidity and mortality in the trauma patient. It has been hypothesised that there is an increased incidence of HUA in patients receiving prehospital transfusion as a result of citrated blood products. This research aimed to determine if there was a difference in arrival ionised calcium (iCa) levels in trauma patients who did and did not receive prehospital transfusion.

METHODS

We conducted a systematic review and meta-analysis of patients with an Injury Severity Score (ISS) > / = 15 and an iCa measured on hospital arrival. We then derived mean iCa levels and attempted to compare between-group variables across multiple study cohorts.

RESULTS

Nine studies reported iCa on arrival to ED, with a mean of 1.08 mmol/L (95% CI 1.02-1.13; I2 = 99%; 2087 patients). Subgroup analysis of patients who did not receive prehospital transfusion had a mean iCa of 1.07 mmol/L (95% CI 1.01-1.14; I2 = 99%, 1661 patients). Transfused patients in the 3 comparative studies had a slightly lower iCa on arrival compared to those who did not receive transfusion (mean difference - 0.03 mmol/L, 95% CI - 0.04 to - 0.03, I2 = 0%, p = 0.001, 561 patients).

CONCLUSION

HUA is common amongst trauma patients irrespective of transfusion. Transfused patients had a slightly lower initial iCa than those without transfusion, though the clinical impact of this remains to be clarified. These findings question the paradigm of citrate-induced hypocalcaemia alone in trauma. There is a need for consensus for the definition of hypocalcaemia to provide a basis for future research into the role of calcium supplementation in trauma.

Massive transfusion protocol reactivation as a novel marker of physician team under-triage after injury

BACKGROUND

Large trauma centers have protocols for the assessment of injury and triaging of care with attempts to over-triage to ensure adequate care for all patients. We noted that a significant number of patients undergo a second massive transfusion protocol (MTP) activation in the first 24 h of care and conducted a retrospective cohort study of patients involved over a 3-year period.

METHODS

Transfusion service records of MTP activations 2019-2021 were linked to Trauma Registry records and divided into cohorts receiving a single versus a reactivation of the MTP. Time of activation and amounts of blood products issued were linked to demographic, injury severity, and outcome data. Categorical and continuous data were compared between cohorts with chi-squared, Fisher's, and Wilcoxan tests as appropriate, and multivariable regression models were used to seek interactions (p < .05).

RESULTS

MTP activation was recorded for 1884 acute trauma patients over our 3-year study period, 142 of whom (7.5%) had reactivation. Factors associated with reactivation included older age (46 vs. 40 years), higher injury severity score (ISS, 27 vs. 22), leg injuries, and presentation during morning shift change (5-7 a.m., 3.3% vs. 7.7%). Patients undergoing MTP reactivation used more RBCs (5 U vs. 2 U) and had more ICU days (3 vs. 2).

CONCLUSIONS

Older patients and those presenting during shift change are at risk for failure to recognize their complex injury patterns and under-triage for trauma care. The fidelity and granularity of transfusion service records can provide unique opportunities for quality assessment and improvement in trauma care.

Age, admission platelet count, and mortality in severe isolated traumatic brain injury: A retrospective cohort study

BACKGROUND

We asked whether patients >50 years of age with acute traumatic brain injury (TBI) present with lower platelet counts and whether lower platelet counts are independently associated with mortality.

METHODS

We combined trauma registry and laboratory data on a retrospective cohort of all patients ≥18 years of age admitted to our Level 1 US regional trauma center 2015-2021 with severe (Head Abbreviated Injury Score [AIS] ≥3), isolated (all other AIS <3) TBI who had a first platelet count within 1 h of arrival. Age and platelet count were assessed continuously and as groups (age 18-50 vs. >50, platelet normals, and at conventional transfusion thresholds). Outcomes such as mean admission platelet counts and in-hospital mortality were assessed categorically and with logistic regression.

RESULTS

Of 44,056 patients, 1298 (3%, median age: 52 [IQR 33,68], 76.1% male) met all inclusion criteria with no differences between younger and older age groups for (ISS; 18 [14,26] vs. 17 [14,26], p = .22), New ISS (NISS; 29 [19,50] vs. 28 [17,50], p = .36), or AIS-Head (4 [3,5] vs. 4 [3,5]; p = .87). Patients aged >50 had lower admission platelet counts (219,000 ± 93,000 vs. 242,000 ± 76,000/μL; p < .001) and greater in-hospital mortality (24.5% vs. 15.6%, p < .001) than those 18-50. In multivariable regression, firearms injuries (OR9.08), increasing age (OR1.004), NISS (OR1.007), and AIS-Head (OR1.05), and decreasing admission platelet counts (OR0.998) were independently associated with mortality (p < .001-.041). Platelet transfusion in the first 4 h of care was more frequent among older patients (p < .001).

CONCLUSIONS

Older patients with TBI had lower admission platelet counts, which were independently associated with greater mortality.

Ultramassive Transfusion for Trauma in the Age of Hemostatic Resuscitation: A Retrospective Single-Center Cohort From a Large US Level-1 Trauma Center, 2011-2021

BACKGROUND

Uncontrolled bleeding is a leading cause of death in trauma. In the last 40 years, ultramassive transfusion (UMT; ≥20 units of red blood cells [RBCs]/24 hours) for trauma has been associated with 50% to 80% mortality; the question remains as to whether the increasing number of units transfused in urgent resuscitation is a marker of futility. We asked whether the frequency and outcomes of UMT have changed in the era of hemostatic resuscitation.

METHODS

We performed a retrospective cohort study of all UMTs in the first 24 hours of care over an 11-year period at a major US level-1 adult and pediatric trauma center. UMT patients were identified, and a dataset was built by linking blood bank and trauma registry data, then reviewing individual electronic health records. Success in achieving hemostatic proportions of blood products was estimated as (units of plasma + apheresis-platelets-in-plasma + cryoprecipitate-pools + whole blood]/[all units given] ≥0.5. Demographics, injury type (blunt or penetrating), severity (Injury Severity Score [ISS]), severity pattern (Abbreviated Injury Scale score for head [AIS-Head] ≥4), admitting laboratory, transfusion, selected emergency department interventions, and discharge status were assessed using χ2 tests of categorical association, the Student t-test of means, and multivariable logistic regression. P <.05 was considered significant.

RESULTS

Among 66,734 trauma admissions from April 6, 2011 to December 31, 2021, we identified 6288 (9.4%) who received any blood products in the first 24 hours, 159 of whom received UMT (0.23%; 154 aged 18-90 + 5 aged 9-17), 81% in hemostatic proportions. Overall mortality was 65% (n = 103); mean ISS = 40; median time to death, 6.1 hours. In univariate analyses, death was not associated with age, sex, or more RBC units transfused beyond 20 but was associated with blunt injury, increasing injury severity, severe head injury, and failure to receive hemostatic blood product ratios. Mortality was also associated with decreased pH and evidence of coagulopathy at admission, especially hypofibrinogenemia. Multivariable logistic regression showed severe head injury, admission hypofibrinogenemia and not receiving a hemostatic resuscitation proportion of blood products as independently associated with death.

CONCLUSIONS

One in 420 acute trauma patients at our center received UMT, a historically low rate. A third of these patients lived, and UMT was not itself a marker of futility. Early identification of coagulopathy was possible, and failure to give blood components in hemostatic ratios was associated with excess mortality.

Transfusion of ABO ‐group identical red blood cells following uncrossmatched transfusion does not lead to higher mortality in civilian trauma patients

BACKGROUND

Questions persist about the safety of switching non-group O recipients of group O uncrossmatched red blood cells (RBC) or low titer group O whole blood (LTOWB) to ABO-identical RBCs during their resuscitation.

METHODS

The database of an earlier nine-center study of transfusing incompatible plasma to trauma patients was reanalyzed. The patients were divided into three groups based on 24-h RBC transfusion: (1) group O patients who received group O RBC/LTOWB units (control group, n = 1203), (2) non-group O recipients who received only group O units (n = 646), (3) non-group O recipients who received at least one unit of group O and non-group O units (n = 562). Fixed marginal effect of receipt of non-O RBC units on 6- and 24-h and 30-day mortality was calculated.

RESULTS

The non-O patients who received only group O RBCs received fewer RBC/LTOWB units and had slightly but significantly lower injury severity score compared to control group; non-group O patients who received both group O and non-O units received significantly more RBC/LTOWB units and had a slightly but significantly higher injury severity score compared to control group. In the multivariate analysis, the non-O patients who received only group O RBCs had significantly higher mortality at 6-h compared to the controls; the non-group O recipients of O and non-O RBCs did not demonstrate higher mortality. At 24-h and 30-days, there were no differences in survival between the groups.

CONCLUSION

Providing non-group O RBCs to non-group O trauma patients who also received group O RBC units is not associated with higher mortality.

Effects of pre-freeze pathogen reduction with riboflavin and UV light on red cells stored post-thaw in AS-3 additive solution

BACKGROUND

Pathogen reduction technology (PRT) may improve the safety of RBCs for transfusion. As the Czech Republic considers PRT, we asked what effects riboflavin and UV light PRT pre-freezing has on the post-thaw recovery and properties of cryopreserved RBCs (CRBCs) after deglycerolization and liquid storage.

STUDY DESIGN AND METHODS

24 Group O whole blood (WB) units were leukoreduced and then treated with riboflavin and UV light PRT (Mirasol, Terumo BCT, USA) before cryopreservation (T-CRBC); 20 similarly-collected units were untreated controls (C-CRBC). Units were processed to RBCs and then cryopreserved with 40% glycerol (wt/vol), frozen at -80°C, stored >118 days, reconstituted as deglycerolized RBC units in AS-3, and stored at 4 ± 2°C for 21 days. One treated unit sustained massive hemolysis during the post-thaw wash process and was removed from data analysis. The remaining units were assessed pre-PRT, post-PRT, and post-thaw-wash on days 0, 7, 14, and 21 for hematocrit, volume, hemoglobin per transfusion unit, pH, % hemolysis, hemoglobin in the supernatant, potassium, phosphorus, NH₃ , osmolality, ATP, and 2,3-diphosphoglycerate.

RESULTS

PRT with leukoreduction caused a 5% loss of RBC followed by a 24% freeze-thaw-wash related loss for a total 28% loss but treated units contained an average of 45 g of hemoglobin, meeting European Union guidelines for CRBC. T-CRBCs displayed higher post-wash hemolysis, potassium, and ammonia concentrations, and lower ATP at the end of storage.

CONCLUSIONS

Cryopreserved RBCs from Riboflavin and UV light-treated WB meet the criteria for clinical use for 7 days after thawing and provide additional protection against infectious threats.

Cryopreservation of apheresis platelets treated with riboflavin and UV light

BACKGROUND

Pathogen reduction technology (PRT) is increasingly used in the preparation of platelets for therapeutic transfusion. As the Czech Republic considers PRT, we asked what effects PRT may have on the recovery and function of platelets after cryopreservation (CP), which we use in both military and civilian blood settings.

STUDY DESIGN AND METHODS

16 Group O apheresis platelets units were treated with PRT (Mirasol, Terumo BCT, USA) before freezing; 15 similarly collected units were frozen without PRT as controls. All units were processed with 5-6% DMSO, frozen at - 80 °C, stored > 14 days, and reconstituted in thawed AB plasma. After reconstitution, all units were assessed for: platelet count, mean platelet volume (MPV), platelet recovery, thromboelastography, thrombin generation time, endogenous thrombin potential (ETP), glucose, lactate, pH, pO2, pCO2, HCO3, CD41, CD42b, CD62, Annexin V, CCL5, CD62P, and aggregates > 2 mm and selected units for Kunicki score.

RESULTS

PRT treated platelet units had lower platelet number (247 vs 278 ×10⁹/U), reduced thromboelastographic MA (38 vs 62 mm) and demonstrated aggregates compared to untreated platelets. Plasma coagulation functions were largely unchanged.

CONCLUSIONS

Samples from PRT units showed reduced platelet number, reduced function greater than the reduced number would cause, and aggregates. While the platelet numbers are sufficient to meet the European standard, marked platelets activation with weak clot strength suggest reduced effectiveness.

How we built a hospital-based community whole blood program

BACKGROUND

Whole blood (WB) is an attractive product for prehospital treatment of hemorrhagic shock and for initial in-hospital resuscitation of patients likely to require massive transfusion. Neither our regional blood provider nor our hospital blood bank had recent experience collecting or using WB, so we developed a stepwise process to gather experience with WB in clinical practice.

METHODS

When our Transfusion Committee suggested a WB program, we worked with our regional blood provider to collect cold-stored, leukoreduced, low-titer anti-A, and anti-B group O RhD positive WB (low-titer group O WB [LTOWB]) and worked with our city Fire Department to integrate it into prehospital care. This work required planning, development of protocols, writing software for blood bank and electronic medical records, changes in paramedic scope of practice, public information, training of clinicians, and close clinical follow-up.

RESULTS

Between June 2019 and December 2021, we received 2269 units of LTOWB and transfused 2220 units; 24 (1%) were wasted, two were withdrawn, and 23 were in stock at the end of that time. Most (89%) were transfused to trauma patients. Usage has grown from 48 to 120 units/month, covers all 5 Fire Districts in the county, and represents about ¼ of all hospital trauma blood product use.

CONCLUSIONS

Developing a WB program is complex but can be started slowly, including both pre-hospital and hospital elements, and expanded as resources and training progress. The investments of time, effort, and funding involved can potentially improve care, save blood bank and nursing effort, and reduce patient charges.

Rate of D-alloimmunization in trauma does not depend on the number of RhD-positive units transfused: The BEST collaborative study

BACKGROUND

Evidence indicates the life-saving benefits of early blood product transfusion in severe trauma resuscitation. Many of these products will be RhD-positive, so understanding the D-alloimmunization rate is important.

METHODS

This was a multicenter, retrospective study whereby injured RhD-negative patients between 18-50 years of age who received at least one unit of RhD-positive red blood cells (RBC) or low titer group O whole blood (LTOWB) during their resuscitation between 1 January, 2010 through 31 December, 2019 were identified. If an antibody detection test was performed ≥14 days after the index RhD-positive transfusion then basic demographic information was collected, including whether the patient became D-alloimmunized. The overall D-alloimmunization rate, and the rate stratified by the number of units transfused, were calculated.

RESULTS

Data were collected from nine institutions. Five institutions reported fewer than 10 eligible patients each and were excluded. From the remaining four institutions, all from the USA, there were 235 eligible patients; 77 (random effects estimate: 32.7%; 95% CI: 19.1-50.1%) became D-alloimmunized. Three of the institutions reported D-alloimmunization rates ≥38.6%, while the remaining institution's rate was 12.2%. In both random and fixed-effects models, the rate of D-alloimmunization was not significantly different between those who received one RhD-positive unit and those who received multiple RhD-positive units.

CONCLUSION

In this large, multicenter study of injured patients, the overall rate of D-alloimmunization fell within the range previously reported. The rate of D-alloimmunization did not increase as the number of transfused RhD-positive units increased. These data can help to inform RhD type selection decisions.

Platelet Transfusion and Outcomes After Massive Transfusion Protocol Activation for Major Trauma: A Retrospective Cohort Study

BACKGROUND

Incorporation of massive transfusion protocols (MTPs) into acute major trauma care has reduced hemorrhagic mortality, but the threshold and timing of platelet transfusion in MTP are controversial. This study aimed to describe early (first 4 hours) platelet transfusion practice in a setting where platelet counts are available within 15 minutes and the effect of early platelet deployment on in-hospital mortality. Our hypothesis in this work was that platelet transfusion in resuscitation of severe trauma can be guided by rapid turnaround platelet counts without excess mortality.

METHODS

We examined MTP activations for all admissions from October 2016 to September 2018 to a Level 1 regional trauma center with a full trauma team activation. We characterized platelet transfusion practice by demographics, injury severity, and admission vital signs (as shock index: heart rate/systolic blood pressure) and laboratory results. A multivariable model assessed association between early platelet transfusion and mortality at 4 hours, 24 hours, and overall in-hospital, with P <.001.

RESULTS

Of the 11,474 new trauma patients admitted over the study period, 469 (4.0%) were massively transfused (defined as ≥10 units of red blood cells [RBCs] in 24 hours, ≥5 units of RBC in 6 hour, ≥3 units of RBC in 1 hour, or ≥4 units of total products in 30 minutes). 250 patients (53.0%) received platelets in the first 4 hours, and most early platelet transfusions occurred in the first hour after admission (175, 70.0%). Platelet recipients had higher injury severity scores (mean ± standard deviation [SD], 35 ± 16 vs 28 ± 14), lower admission platelet counts (189 ± 80 × 109/L vs 234 ± 80 × 109/L; P < .001), higher admission shock index (heart rate/systolic blood pressure; 1.15 ± 0.46 vs 0.98 ± 0.36; P < .001), and received more units of red cells in the first 4 hours (8.7 ± 7.7 vs 3.3 ± 1.6 units), 24 hours (9 ± 9 vs 3 ± 2 units), and in-hospital (9 ± 8 vs 3 ± 2 units) than nonrecipients (all P < .001). We saw no difference in 4-hour (8% vs 7.8%; P = .4), 24-hour (16.4% vs 10.5%; P = .06), or in-hospital mortality (30.4% vs 23.7%; P = .1) between platelet recipients and nonrecipients. After adjustment for age, injury severity, head injury, and admission physiology/laboratory results, early platelet transfusion was not associated with 4-hour, 24-hour, or in-hospital mortality.

CONCLUSIONS

In an advanced trauma care setting where platelet counts are available within 15 minutes, approximately half of massively transfused patients received early platelet transfusion. Early platelet transfusion guided by protocol-based clinical judgment and rapid-turnaround platelet counts was not associated with increased mortality.

Blood product availability in the Washington state trauma system

BACKGROUND

Early transfusion can prolong life in injured patients awaiting definitive hemorrhage control. We conducted a community resources assessment of blood product availability at hospitals within the Washington State (WA) Regional Trauma System, with the expectation that a minority of Level IV and V centers would have blood products routinely available for use in resuscitation.

METHODS

We designed a questionnaire soliciting information on routinely available unit quantities of red blood cells (RBC), plasma, platelets, cryoprecipitate, and/or whole blood and submitted this questionnaire electronically to the 82 WA designated trauma centers (Levels I-V). Non-responders were contacted directly by telephone. The study was conducted in September and October 2021. US 2020 census data were used to correlate results with local population densities.

RESULTS

First-round contact netted responses from 57 (70%) centers; the remaining centers provided information via telephone, for a 100% final response. Packed RBC were available in 79 of the 82 centers (96%; range 6-220 units); plasma, 62 centers (76%, range 1-100 units); platelets, 40 centers (49%, range 1-8 units); cryoprecipitate, 45 centers (55%, range 1-20 units). Whole blood was only available at the Level I center. Three Level V centers, located in 2 of the 8 WA state trauma regions, reported no routine blood availability. The two trauma regions affected represent 12% of the state's population and more than a third of its geographic area.

CONCLUSIONS

Within the WA regional trauma system, blood products are wide, if unevenly, available. Large urban/rural disparities in availability exist that should be explored.

Advances in hemorrhage control resuscitation

PURPOSE OF REVIEW

Despite significant advances in trauma management over the last twenty years, uncontrolled hemorrhage remains the leading cause of preventable death in trauma. We review recent changes affecting hemorrhage control resuscitation.

RECENT FINDINGS

Early blood product usage has become well established as a standard of care in trauma hemorrhage control. To enable this, low titer group A liquid plasma and group O whole blood are increasingly utilized. Single donor apheresis platelets have now replaced pooled donor platelets in the USA and are often pathogen reduced, which has implications for trauma resuscitation. Further work is examining timing and dosing of tranexamic acid and the debate in factor concentrate usage in trauma induced coagulopathy continues to evolve. The 'Stop the bleed' campaign has highlighted how important the use of hemostatic dressings are in hemorrhage control, as too is the expanded use of endovascular aortic occlusion. We highlight the ongoing research into desmopressin use and the undetermined significance of ionized calcium levels in trauma. Finally, we discuss our own hospital experience with coagulation testing and the paucity of evidence of improved outcomes with viscoelastic testing.

SUMMARY

Improving trauma coagulopathy diagnostics and hemorrhage control are vital if we are to decrease the mortality associated with trauma.

Providing whole blood for an urban paramedical ambulance system

INTRODUCTION

Hemorrhage is the second leading cause of death among urban trauma patients, and the provision of prehospital blood-based resuscitation can be lifesaving. We developed an efficient system to support blood-based resuscitation by an urban advanced life support ambulance system.

METHODS

We worked with our state health department for permission for fire department paramedics to initiate blood transfusion and built protocols for field whole blood resuscitation. Our regional trauma center transfusion service provided 2 units of O positive, low-titer, leukoreduced whole blood in an internally monitored and sealed ice box weighing 10 pounds to the fire department paramedic supervisor. When notified, the supervisor transported the blood to the sites of anticipated need. Total blood use and wastage were recorded.

RESULTS

Following two public hearings, we obtained state-wide approval for the initiation of emergency uncrossmatched blood transfusion by paramedics. Over a 1-year period beginning August 27, 2019, 160 units of whole blood were made available for use, and 51 units were transfused to 39 patients, 30 of whom were trauma patients. Other recipients include patients in shock from massive gastrointestinal, peripartum, or other suspected bleeding. Unused units were returned to the providing transfusion service after 1 week and used for hospital patient care without loss. The estimated cost of providing blood per mission was $0.28 and per patient transfused was $1138.

CONCLUSIONS

With appropriate attention to detail, it is possible to provide whole blood to an urban paramedical ambulance system with efficient blood component usage, minimal blood wastage, and low cost.

Blood component use and injury characteristics of acute trauma patients arriving from the scene of injury or as transfers to a large, mature US Level 1 trauma center serving a large, geographically diverse region

BACKGROUND

Advanced trauma care demands the timely availability of hemostatic blood products, posing special challenges for regional systems in geographically diverse areas. We describe acute trauma blood use by transfer status and injury characteristics at a large regional Level 1 trauma center.

STUDY DESIGN AND METHODS

We reviewed Harborview Medical Center (HMC) Trauma Registry, Transfusion Service, and electronic medical records on acute trauma patients for demographics, injury patterns, blood use, and in-hospital mortality, 2011-2019.

RESULTS

Among 47,471 patients (mean age 45.2 ± 23.0 years; 68.3% male; Injury Severity Score 12.6 ± 11.1), 4.7% died and 8547 (18%) received at least one blood component through HMC. Firearms injuries were the most often transfused (690/2596, 26.6%) and the most urgently (39.9% ≥3 units in <1 h; 40.6% ≥5 units in <4 h), and had the highest mortality (case-fatality, 12.2%) (all p < .001). From-scene patients were younger than transfers (42.9 ± 21.0 vs. 47.2 ± 24.4), predominated among firearms injuries (68.2% from-scene vs. 31.8% transfers), were more likely to receive blood (18.5% vs. 17.6%) more urgently (≥3 units first hour, 24.4% vs. 7.7%; ≥5 units first 4 h: 25.6% vs. 8.2%), were more likely to die of hemorrhage (15.5% vs. 4.3%) and from firearms injuries (310/1360, 22.8%) (all p < .001).

DISCUSSION

Early blood use, firearms injuries, and mortality were all greater among from-scene patients, and firearms injuries had worse outcomes despite greater and more urgent blood use, but the role of survivor bias for transfer patients must be clarified. Future research must identify strategies for providing local hemostatic transfusion support, particularly for firearms injuries.

Cold-stored whole blood and platelet counts in severe acute injury: A comparison of four retrospective cohorts

BACKGROUND

Low-titer group O whole blood (LTOWB) is attractive for acute trauma care as it delivers concentrated and balanced hemostatic resuscitation in single large bags. Whether cold-stored LTOWB can sustain platelet counts is unclear.

STUDY DESIGN AND METHODS

Four cohorts of trauma patients-three historic, one retrospective-were identified by their urgency of blood use. Admission and all subsequent platelet counts over the first 24 h of care were compared with t-tests. The cohorts were as follows: 1292 patients at Maryland Shock Trauma as described by Stansbury and colleagues in 2013; 35 patients enrolled locally in the 1:1:2 arm of the pragmatic randomized optimal plasma and platelet ratios (PROPPR) trial; 34 patients enrolled locally in the 1:1:1 arm of PROPPR; and 59 patients receiving more than 3 units of LTOWB enroute to or at our Level 1 trauma center, 2019-2020.

RESULTS

Mean age of LTOWB units transfused was 9 ± 5 days and mean dose was 5 ± 2 units. All four cohorts were profoundly injured (mean Injury Severity Score ≥ 31), with mean first platelet counts 204-228 K/μ and subsequent counts approximately 100 k/μl lower. Through the first 24 h of care, mean platelet counts decreased least, 79 and 83 10³ /μl, in the 1:1:1 PROPPR and LTOWB cohorts. Mean platelet counts in patients transfused with LTOWB remained stable after the third hour of care.

DISCUSSION

LTOWB transfusion was associated with lesser mean decrease in platelet counts during the first 24 h after injury, similar to those observed among patients receiving components 1:1:1 component in the PROPPR study.

Hemostatic Resuscitation of Pediatric Trauma Patients During Air Medical Transport: A Retrospective Matched Cohort Study

OBJECTIVE

The objective of this study was to examine an academic air ambulance service's experience with prehospital transfusion of plasma and red blood cells in pediatric trauma for evidence of efficacy on the treatment of shock and coagulopathy.

METHODS

All trauma patients < 18 years old transfused during transport by the University of Washington Airlift Northwest (Airlift) air medical transport service to Harborview Medical Center, Seattle, WA, were identified. Controls were matched 1:1 from pediatric trauma patients transported by Airlift before transfusion support became available. Demographics, injury scores, emergency department admission and interval laboratory values, blood product use, and hospital outcome measures were registered.

RESULTS

Seventeen cases met the inclusion criteria and were matched by age and Injury Severity Score to 17 control patients (mean age = 10.5 vs. 10.9 years; New Injury Severity Score, 37 vs. 40.7). No significant differences in vital signs, shock index, or mortality were observed. Cases received less in-flight crystalloid (4.3 mL/kg vs. 16.9 mL/kg, P = .004), had higher admission fibrinogen levels (238 vs. 148mg/dL, P = .007), and shorter time to normalization of the international normalized ratio (6.4 vs. 19.1 hours, P = .04).

CONCLUSIONS

In this small series, hemostatic resuscitation during air medical transport was associated with less crystalloid administration and better support of coagulation indices.

Association Between Ionized Calcium Concentrations During Hemostatic Transfusion and Calcium Treatment With Mortality in Major Trauma

BACKGROUND

Transfusion of citrated blood products may worsen resuscitation-induced hypocalcemia and trauma outcomes, suggesting the need for protocolized early calcium replacement in major trauma. However, the dynamics of ionized calcium during hemostatic resuscitation of severe injury are not well studied. We determined the frequency of hypocalcemia and quantified the association between the first measured ionized calcium concentration [iCa] and calcium administration early during hemostatic resuscitation and in-hospital mortality.

METHODS

We performed a retrospective cohort study of all admissions to our regional level 1 trauma center who (1) were ≥15 years old; (2) presented from scene of injury; (3) were admitted between October 2016 and September 2018; and (4) had a Massive Transfusion Protocol activation. They also (1) received blood products during transport or during the first 3 hours of in-hospital care (1st3h) of trauma center care and (2) had at least one [iCa] recorded in that time. Demographic, injury severity, admission shock and laboratory data, blood product use and timing, and in-hospital mortality were extracted from Trauma Registry and Transfusion Service databases and electronic medical records. Citrate load was calculated on a unit-by-unit basis and used to calculate an administered calcium/citrate molar ratio. Univariate and multivariable logistic regression analyses for the binary outcome of in-hospital death were performed.

RESULTS

A total of 11,474 trauma patients were admitted to the emergency department over the study period, of whom 346 (3%; average age: 44 ± 18 years; 75% men) met all study criteria. In total, 288 (83.2%) had hypocalcemia at first [iCa] determination; 296 (85.6%) had hypocalcemia in the last determination in the 1st3h; and 177 (51.2%) received at least 1 calcium replacement dose during that time. Crude risk factors for in-hospital death included age, injury severity score (ISS), new ISS (NISS), Abbreviated Injury Scale (AIS) head, admission systolic blood pressure (SBP), pH, and lactate; all P < .001. Higher in-hospital mortality was significantly associated with older age, higher NISS, AIS head, and admission lactate, and lower admission SBP and pH. There was no relationship between mortality and first [iCa] or calcium dose corrected for citrate load.

CONCLUSIONS

In our study, though most patients had hypocalcemia during the 1st3h of trauma center care, neither first [iCa] nor administered calcium dose corrected for citrate load were significantly associated with in-patient mortality. Clinically, hypocalcemia during early hemostatic resuscitation after severe injury is important, but specific treatment protocols must await better understanding of calcium physiology in acute injury.

Rates of delayed hemolytic transfusion reactions observed in a trauma center

BACKGROUND

Delayed hemolytic transfusion reactions (DHTRs) are reported to be rare occurrences but may be more frequently observed in the trauma setting where patients are heavily transfused, followed over long inpatient admissions, and have frequent subsequent blood counts as they undergo multiple surgical interventions.

STUDY DESIGN AND METHODS

We examined the rates of DHTRs on a per transfusion and per patient basis in an academic county hospital with a level 1 trauma center serving a four-state region and over a 3-year period. DHTRs were entered sequentially into a registry as they were observed, and a retrospective review of all new alloantibodies detected was performed to identify any additional DHTRs. The number of units of red blood cells (RBCs), the number of unique patients, types of alloantibodies, and number of transfusions were extracted from blood bank records.

RESULTS

Twenty-nine DHTRs were observed from January 1, 2017, through December 31, 2019, from newly observed alloantibodies after a median of 12 red blood cells (RBCs) transfusions per patient. These reactions occurred in response to 24,633 unique transfusions in 6905 unique patients, so the observed rates were about 1:849 RBC transfusions and 1:238 transfused patients. Evidence of delayed hemolysis was seen in five additional patients who were transfused during emergency resuscitation and later found to have had known RBC antibodies.

DISCUSSION

We report a higher rate of DHTRs than previously described to demonstrate that DHTRs are not rare in trauma centers.

Evidence-Based and Clinically Relevant Outcomes for Hemorrhage Control Trauma Trials

OBJECTIVE

To address the clinical and regulatory challenges of optimal primary endpoints for bleeding patients by developing consensus-based recommendations for primary clinical outcomes for pivotal trials in patients within 6 categories of significant bleeding, (1) traumatic injury, (2) intracranial hemorrhage, (3) cardiac surgery, (4) gastrointestinal hemorrhage, (5) inherited bleeding disorders, and (6) hypoproliferative thrombocytopenia.

BACKGROUND

A standardized primary outcome in clinical trials evaluating hemostatic products and strategies for the treatment of clinically significant bleeding will facilitate the conduct, interpretation, and translation into clinical practice of hemostasis research and support alignment among funders, investigators, clinicians, and regulators.

METHODS

An international panel of experts was convened by the National Heart Lung and Blood Institute and the United States Department of Defense on September 23 and 24, 2019. For patients suffering hemorrhagic shock, the 26 trauma working-group members met for almost a year, utilizing biweekly phone conferences and then an in-person meeting, evaluating the strengths and weaknesses of previous high quality studies. The selection of the recommended primary outcome was guided by goals of patient-centeredness, expected or demonstrated sensitivity to beneficial treatment effects, biologic plausibility, clinical and logistical feasibility, and broad applicability.

CONCLUSIONS

For patients suffering hemorrhagic shock, and especially from truncal hemorrhage, the recommended primary outcome was 3 to 6-hour all-cause mortality, chosen to coincide with the physiology of hemorrhagic death and to avoid bias from competing risks. Particular attention was recommended to injury and treatment time, as well as robust assessments of multiple safety related outcomes.

Economical provision of blood components for critical patient transport across a large geographic area

BACKGROUND

Rapid air transport of critically injured patients to sites of appropriate care can save lives. The provision of blood products on critical care transport flights may save additional lives by starting resuscitation earlier.

METHODS

Our regional trauma center transfusion service provided 2 units of O-negative red blood cells and 2 units of A low-titer anti-B liquid plasma in an internally monitored and sealed eutectic box weighing 10.4 pounds to eight air bases once weekly. Flight crews were instructed to transfuse plasma units first. Unused blood was returned to the transfusion service. Total blood use and wastage were recorded.

RESULTS

Over a 6-year period, ≈ 7400 blood components were provided, and >1000 were used by the air transport service in patient care. Plasma units were 57% of all units given. Unused units were returned to the providing transfusion service and used in hospital patient care with <3% loss. Estimated cost of providing blood per mission was $63 and per patient transfused was $1940.

CONCLUSIONS

With appropriate attention to detail, it is possible to provide life-saving blood components to aeromedical transport services across a large geographic area with efficient blood component usage, minimal blood wastage, and low cost.

Epidemiological survey and screening strategy for dengue virus in blood donors from Yunnan Province

Background

Dengue virus (DENV) infection is increasingly common in southern China and can be transmitted through blood transfusion but is not currently part of donor screening throughout the region. We assessed DENV prevalence among donors at the Xishuangbanna Blood Center, Yunnan, to support development of DENV screening strategies.

Methods

Blood samples were collected randomly between June 2019 and August 2019. These were screened for anti-DENV IgG and IgM using enzyme-linked immunosorbent assay (ELISA). Then, all reactive samples and some randomly-chosen non-reactive samples were used to detect DENV RNAs using real-time polymerase-chain-reaction (RT-PCR) assays. After RT-PCR, samples were further tested for soluble nonstructural protein 1 (NS1) using the colloidal gold method. Donors demographics were also collected and assessed.

Results

Over the study period, 2254 donor samples were collected and tested for anti-DENV IgG and IgM by ELISA. This revealed 598 anti-DENV IgG and/or IgM reactive samples, a serological prevalence of 26.53%. Of these, 26 were RT-PCR positive and/or NS1 positive. Significant differences in DENV prevalence were noted by occupation (P = 0.001), education (P < 0.001), and ethnicity (P = 0.026).

Conclusion

The prevalence of DENV in Xishuangbanna Blood Center was higher than most other blood centers that have implemented DENV donor screening. Our study provides first-hand data about the prevalence of DENV and allows the development of a screening strategy for clinical use.

Re-introducing whole blood for transfusion: considerations for blood providers

Whole blood is the original blood preparation but disappeared from the blood bank inventories in the 1980s following the advent of component therapy. In the early 2000s, both military and civilian practice called for changes in the transfusion support for massive haemorrhage. The 'clear fluid' policy was abandoned and replaced by early balanced transfusion of platelets, plasma and red cells. Whole blood is an attractive alternative to multi-component therapy, which offers reduced hemodilution, lower donor exposure and simplified logistics. However, the potential for wider re-introduction of whole blood requires re-evaluation of haemolysins, storage conditions and shelf-life, the need for leucocyte depletion/ pathogen reduction and inventory management for blood providers. This review addresses these questions and calls for research to define the optimal whole blood product and the indications for its use.

Transfusion of blood components containing ABO-incompatible plasma does not lead to higher mortality in civilian trauma patients

BACKGROUND

This study investigated the effect on mortality of transfusing ABO-incompatible plasma from all sources during trauma resuscitation.

METHODS

Demographic, transfusion, and survival data were retrospectively extracted on civilian trauma patients. Patients were divided by receipt of any quantity of ABO-incompatible plasma from any blood product (incompatible group) or receipt of solely ABO-compatible plasma (compatible group). The primary outcome was 30-day mortality, while other outcomes included 6- and 24-hour mortality. Mixed-effects logistic regression was used to model the effect of various predictor variables, including receipt of incompatible plasma, on mortality outcomes.

RESULTS

Nine hospitals contributed data on a total of 2618 trauma patients. There were 1282 patients in the incompatible group and 1336 patients in the compatible group. In both the unadjusted and adjusted models, the 6-hour, 24-hour, and 30-day mortality rates were not significantly different between these groups. The patients in the incompatible group were then divided into high volume (>342 mL) and low volume (≤342 mL) incompatible plasma recipients. In the adjusted model, the high-volume group had higher 24-hour mortality when the Trauma Injury Severity Score survival prediction was >50%. Mortality at 6 hours and 30 days was not higher in this model. The low-volume group did not have increased mortality at any of the time points in this adjusted model.

CONCLUSION

The transfusion of incompatible plasma in civilian trauma resuscitation does not lead to higher 30-day mortality. The finding of higher mortality in a select group of recipients in the secondary analysis warrants further study.

Blood use and transfusion needs at a large health care system in Washington state during the SARS-CoV-2 pandemic

BACKGROUND

This report evaluates hospital blood use trends during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, and identifies factors associated with the need for transfusion and risk of death in patients with coronavirus 2019 (COVID-19).

METHODS

Overall hospital blood use and medical records of adult patients with COVID-19 were extracted for two institutions. Multivariate logistic regression models were conducted to estimate associations between the outcomes transfusion and mortality and patient factors.

RESULTS

Daily blood use decreased compared to pre-COVID-19 levels; the effect was more significant for platelets (29% and 34%) compared to red blood cells (25% and 20%) at the two institutions, respectively. Surgical and oncologic services had a decrease in average daily use of platelets of 52% and 30%, and red blood cells of 39% and 25%, respectively. A total of 128 patients with COVID-19 were hospitalized, and 13 (10%) received at least one transfusion due to anemia secondary to chronic illness (n = 7), recent surgery (n = 3), and extracorporeal membrane oxygenation (n = 3). Lower baseline platelet count and admission to the intensive care unit were associated with increased risk of transfusion. The blood group distribution in patients with COVID-19 was 37% group O, 40% group A, 18% group B, and 5% group AB. Non-type O was not associated with increased risk of mortality.

CONCLUSION

The response to the SARS-CoV-2 pandemic included changes in routine hospital operations that allowed for the provision of a sufficient level of care for patients with and without COVID-19. Although blood type may play a role in COVID-19 susceptibility, it did not seem to be associated with patient mortality.

Improving emergency department blood product use through nursing education

BACKGROUND

Rapid access to blood products can be lifesaving for hemorrhaging patients, but placing blood components in easily accessible locations in the emergency department (ED) can lead to wasteful patterns of use. Education can lead to improvements in transfusion behavior, but such changes for the better are often short lived.

METHODS

To facilitate the early initiation of balanced resuscitation, an emergency blood refrigerator was placed in our ED in February 2015. Physician education to give blood components in a 1:1 plasma:red blood cell (RBC) unit ratio with the plasma given first was given repeatedly with short-term success. Finally, nurses were trained and empowered to strongly suggest that blood components be given in balanced ratios and that plasma be given first. Plasma:RBC unit ratios were compared in successive years with the chi-square test for trend.

RESULTS

A total of 1165 RBC units and 623 plasma units were issued from the ED emergency blood refrigerator over 5 years. Intensive physician education is documented at start, in late 2016 to early 2017, and again in early and late 2018. Ratios of components (U plasma/U RBCs) were 2015, 17%; 2016, 26%; 2017, 61%; 2018, 49%; and 2019, 91% (p < 10^-18 chi-square for trend). Higher ratios of plasma use were associated with $40,000+ annual savings.

CONCLUSIONS

Giving the ED senior nurses formal education about the need for and a policy to give guidance on massive transfusion protocol (MTP) blood component administration sequence has achieved compliance with our MTP's intention. Increasing plasma use reduces group O RBC use and total blood costs.

Prepare to adapt: blood supply and transfusion support during the first 2 weeks of the 2019 novel coronavirus (COVID-19) pandemic affecting Washington State

BACKGROUND

The first coronavirus (COVID-19) case was reported in United States in the state of Washington, approximately 3 months after the outbreak in Wuhan, China. Three weeks later, the US federal government declared the pandemic a national emergency. The number of confirmed COVID-19 positive cases increased rather rapidly and changed routine daily activities of the community.

STUDY DESIGN AND METHODS

This brief report describes the response from the hospital, the regional blood center, and the hospital-based transfusion services to the events that took place in the community during the initial phases of the pandemic.

RESULTS

In Washington State, the first week of March started with four confirmed cases and ended with 150; by the end of the second week of March there were more than 700 cases of confirmed COVID-19. During the first week, blood donations dropped significantly. Blood units provided from blood centers of nonaffected areas of the country helped keep inventory stable and allow for routine hospital operations. The hospital-based transfusion service began prospective triaging of blood orders to monitor and prioritize blood usage. In the second week, blood donations recovered, and the hospital postponed elective procedures to ensure staff and personal protective equipment were appropriate for the care of critical patients.

CONCLUSION

As community activities are disrupted and hospital activities switch from routine operations to pandemic focused and urgent care oriented, the blood supply and usage requires a number of transformations.

Blood School

OBJECTIVES

To describe and evaluate a laboratory-based nursing education activity on transfusion to improve patient safety, an often-neglected opportunity.

METHODS

Our transfusion service developed a day-long "Blood School" to provide knowledge, skills, and behaviors to nurses in four aspects of transfusion: blood ordering, sample collection, transfusion procedures, and recognition and reporting of transfusion reactions. We collected survey data on methods and effects of training and hard data on the number of reported patient safety events.

RESULTS

Nurses want more hands-on experience to understand transfusion concepts, practice hospital procedures, recognize latent problems, and have behaviors to act effectively. We observed that engagement and understanding are best where participation is highest. Reported patient safety events were lower even as self-reported nursing mistakes increased.

CONCLUSIONS

Blood School is a well-received and effective site for nursing education in transfusion. We seek ways to extend and improve laboratory-based nursing training to improve patient safety.

Red Blood Cell Transfusions and Anemia on Admission Are Associated with Poor Outcomes in Necrotizing Soft Tissue Infections

BACKGROUND

Necrotizing soft tissue infections (NSTIs) are highly morbid infections often requiring critical care and transfusion support. We explored a large 2-year experience from a regional trauma center with a dedicated soft tissue service (STS) in an attempt to identify factors in current care with potential for improving outcomes for these critically ill patients.

METHODS

New adult (>17 years) STS admissions, 2008-2009, were identified from the Trauma Registry. Patient records were extracted and assessed via descriptive statistics, univariate analysis, and multivariable logistic regression models.

RESULTS

Mortality among 253 eligible primary admissions was 8.3% overall and 10.3% for those with an admission diagnosis of NSTI. No significant differences in wound characteristics, use of VAC (vacuum-assisted closure) dressing or hyperbaric oxygen, or wound microbiology emerged between survivors and nonsurvivors. Median time to first debridement was 5 h (interquartile range, 2-21 h). Multivariable modeling indicated association of worse outcome (death or discharge to chronic/rehab care) with age >60 years [odds ratio (OR), 3.82; P < 0.001], anemia (OR, 0.98; P = 0.03), increasing number of transfusions (OR, 1.09; P < 0.001), NSTI diagnosis (OR, 2.47; P = 0.005), preexisting diabetes mellitus (OR, 3.20; P = 0.001), and low admission hemoglobin (OR, 0.80; P = 0.004).

CONCLUSIONS

Mortality was less than previously reported. Number of transfusions and anemia at admission emerged as risk factors for poor outcomes. Future research should focus on the effects of transfusion on NSTI outcomes, on potentially confounding factors, and on whether a restrictive transfusion strategy reduces mortality.

Genetic Testing to Resolve the Source of Hemolytic Antibody in Solid Organ Transplantation

Introduction

Antibody-mediated hemolysis arising in the face of solid organ transplant can be devastating. Some degree of passenger lymphocyte syndrome is said to occur in up to 10% of ABO mismatched renal transplants, 40% of ABO mismatched liver transplants, and 70% of ABO mismatched heart-lung transplants, a reflection of the number of memory B-cells transplanted with the organ. Passenger lymphocyte syndrome is less common with minor antigens but can still be severe.

Materials and Methods

A series of patients developed immune hemolytic anemia after solid organ transplantation. Conventional serologic testing was performed using tube and solid-phase testing. Molecular testing was performed using gene-chip array.

Results

In patients receiving a minor antigen mismatched organ transplant and multiple allogenic red cell transfusions, serologic methods proved insufficient to resolve the source of minor blood group antibodies that arose in the aftermath of transplant. Genetic testing was able to clearly resolve donor and recipient types.

Conclusions

Passenger lymphocyte syndrome after mismatched organ transplantation is not rare. The mixtures of organ donor, recipient, and other transfused RBCs profoundly limit the usefulness of serologic testing. Genetic assignment of minor blood types to donor and recipient can guide therapy and inform prognosis.