Too little too late: Hypotension and blood transfusion in the trauma bay are independent predictors of death in injured children

Association Between Whole Blood Transfusion and Mortality Among Injured Pediatric Patients

OBJECTIVE

The aim of this study was to assess the association between whole blood (WB) and mortality among injured children who received immediate blood transfusion.

BACKGROUND

The use of WB for transfusion therapy in trauma has been revisited, and recent studies have reported an association between WB and improved survival among adults. However, evidence of a similar association lacks in children.

METHODS

We performed a retrospective cohort study from the American College of Surgeons Trauma Quality Improvement Program (ACS-TQIP) between 2020 and 2021. Patients were aged less than or equal to 16 years and had immediate blood transfusion within 4 hours of hospital arrival. Survival at 24 hours and 30 days were compared after creating 1:1 propensity score-matched cohorts, matching for demographics, injury type, vital signs on admission, trauma severity scores, hemorrhage control procedures, hospital characteristics, and the need for massive transfusion.

RESULTS

A total of 2729 patients were eligible for analysis. The median age was 14 years (interquartile range: 8-16 years); 1862 (68.2%) patients were male; and 1207 (44.2%) patients were White. A total of 319 (11.7%) patients received WB. After a 1:1 ratio propensity score matching, 318 matched pairs were compared. WB transfusion was associated with improved survival at 24 hours, demonstrating a 42% lower risk of mortality (hazard ratio, 0.58; 95% CI, 0.34-0.98; P =0.042) Similarly, the survival benefit associated with WB transfusion remained consistent at 30 days (hazard ratio, 0.65; 95% CI, 0.46-0.90; P =0.011).

CONCLUSION

The use of WB was associated with improved survival among injured pediatric patients requiring immediate transfusion.

Balanced resuscitation with whole blood versus component therapy in critically injured preadolescent children: Getting there faster with fewer exposures

PURPOSE

Balanced blood product resuscitation with red blood cells, plasma, and platelets can be achieved using whole blood (WB) or component therapy (CT). However, balanced resuscitation of younger children with severe traumatic hemorrhage may be complicated by delays in delivering all blood components and concerns regarding multiple product exposures. We hypothesized that WB achieves balanced resuscitation faster than CT, with fewer product exposures and improved clinical outcomes.

METHODS

Children younger than 12 years receiving balanced resuscitation within 4 hours of arrival were identified from the 2017 to 2019 Trauma Quality Improvement Program database. Time to balanced resuscitation was defined as the time of initiation of WB or all three components. Patient characteristics, resuscitation details, and outcomes were compared between WB and CT groups. Time to balanced resuscitation was compared using Kaplan-Meier analysis and Cox regression modeling to adjust for covariates. Additional multivariable regression models compared number of transfusion exposures, intensive care unit (ICU) length of stay, and mortality.

RESULTS

There were 390 patients (109 WB, 281 CT) with median age 7 years, 12% penetrating mechanism, 42% severe traumatic brain injury, and 49% in-hospital mortality. Time to balanced resuscitation was shorter for WB versus CT (median, 28 vs. 87 minutes; hazard ratio [HR], 2.93; 95% confidence interval [CI], 2.31-3.72; p < 0.0001). Whole blood patients received fewer transfusion exposures (mean, 3.2 vs. 3.9; adjusted incidence rate ratio, 0.82; 95% CI, 0.72-0.92; p = 0.001) and lower total product volumes (50 vs. 85 mL/kg; p = 0.01). Intensive care unit stays trended shorter for WB versus CT (median, 10 vs. 12 days; adjusted HR, 1.32; 95% CI, 0.93-1.86), while in-hospital mortality was similar (50% vs. 45%; adjusted odds ratio, 1.11; 95% CI, 0.65-1.88).

CONCLUSION

In critically injured preadolescent children receiving emergent transfusion, WB was associated with faster time to balanced resuscitation, fewer transfusion exposures, lower blood product volumes, and a trend toward shorter ICU stays than CT.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level III.

Canadian tertiary care pediatric massive hemorrhage protocols: a survey and comprehensive national review

PURPOSE

Hemorrhage is the leading cause of pediatric death in trauma and cardiac arrest during surgery. Adult studies report improved patient outcomes using massive hemorrhage protocols (MHPs). Little is known about pediatric MHP adoption in Canada.

METHODS

After waived research ethics approval, we conducted a survey of Canadian pediatric tertiary care hospitals to study MHP activations. Transfusion medicine directors provided hospital/patient demographic and MHP activation data. The authors extracted pediatric-specific MHP data from requested policy/procedure documents according to seven predefined MHP domains based on the literature. We also surveyed educational and audit tools. The analysis only included MHPs with pediatric-specific content.

RESULTS

The survey included 18 sites (100% response rate). Only 13/18 hospitals had pediatric-specific MHP content: eight were dedicated pediatric hospitals, two were combined pediatric/obstetrical hospitals, and three were combined pediatric/adult hospitals. Trauma was the most common indication for MHP activation (54%), typically based on a specific blood volume anticipated/transfused over time (10/13 sites). Transport container content was variable. Plasma and platelets were usually not in the first container. There was little emphasis on balanced plasma/platelet to red-blood-cell ratios, and most sites (12/13) rapidly incorporated laboratory-guided goal-directed transfusion. Transfusion thresholds were consistent with recent guidelines. All protocols used tranexamic acid and eight sites used an audit tool.

DISCUSSION/CONCLUSION

Pediatric MHP content was highly variable. Activation demographics suggest underuse in nontrauma settings. Our findings highlight the need for a consensus definition for pediatric massive hemorrhage, a validated pediatric MHP activation tool, and prospective assessment of blood component ratios. A national pediatric MHP activation repository would allow for quality improvement metrics.

Association of Prehospital Transfusion With Mortality in Pediatric Trauma

Importance

Optimal hemostatic resuscitation in pediatric trauma is not well defined.

Objective

To assess the association of prehospital blood transfusion (PHT) with outcomes in injured children.

Design, Setting, and Participants

This retrospective cohort study of the Pennsylvania Trauma Systems Foundation database included children aged 0 to 17 years old who received a PHT or emergency department blood transfusion (EDT) from January 2009 and December 2019. Interfacility transfers and isolated burn mechanism were excluded. Analysis took place between November 2022 and January 2023.

Exposure

Receipt of a blood product transfusion in the prehospital setting compared with the emergency department.

Main Outcomes and Measures

The primary outcome was 24-hour mortality. A 3:1 propensity score match was developed balancing for age, injury mechanism, shock index, and prehospital Glasgow Comma Scale score. A mixed-effects logistic regression was performed in the matched cohort further accounting for patient sex, Injury Severity Score, insurance status, and potential center-level heterogeneity. Secondary outcomes included in-hospital mortality and complications.

Results

Of 559 children included, 70 (13%) received prehospital transfusions. In the unmatched cohort, the PHT and EDT groups had comparable age (median [IQR], 47 [9-16] vs 14 [9-17] years), sex (46 [66%] vs 337 [69%] were male), and insurance status (42 [60%] vs 245 [50%]). The PHT group had higher rates of shock (39 [55%] vs 204 [42%]) and blunt trauma mechanism (57 [81%] vs 277 [57%]) and lower median (IQR) Injury Severity Score (14 [5-29] vs 25 [16-36]). Propensity matching resulted in a weighted cohort of 207 children, including 68 of 70 recipients of PHT, and produced well-balanced groups. Both 24-hour (11 [16%] vs 38 [27%]) and in-hospital mortality (14 [21%] vs 44 [32%]) were lower in the PHT cohort compared with the EDT cohort, respectively; there was no difference in in-hospital complications. Mixed-effects logistic regression in the postmatched group adjusting for the confounders listed above found PHT was associated with a significant reduction in 24-hour (adjusted odds ratio, 0.46; 95% CI, 0.23-0.91) and in-hospital mortality (adjusted odds ratio, 0.51; 95% CI, 0.27-0.97) compared with EDT. The number needed to transfuse in the prehospital setting to save 1 child's life was 5 (95% CI, 3-10).

Conclusions and Relevance

In this study, prehospital transfusion was associated with lower rates of mortality compared with transfusion on arrival to the emergency department, suggesting bleeding pediatric patients may benefit from early hemostatic resuscitation. Further prospective studies are warranted. Although the logistics of prehospital blood product programs are complex, strategies to shift hemostatic resuscitation toward the immediate postinjury period should be pursued.

Balanced resuscitation: application to the paediatric trauma population

PURPOSE OF REVIEW

Trauma is the leading cause of death in children over 5 years old. Early mortality is associated with trauma-induced coagulopathy (TIC), with balanced resuscitation potentially mitigating the effects of TIC. We review TIC, balanced resuscitation and the best evidence for crystalloid fluid versus early blood products, massive transfusion protocol (MTP) and the optimal ratio for blood products.

RECENT FINDINGS

Crystalloid fluids have been associated with adverse events in paediatric trauma patients. However, the best way to implement early blood products remains unclear; MTP has only shown improved time to blood products without clear clinical improvement. The indications to start blood products are also currently under investigation with several scoring systems and clinical indications being studied. Current studies on the blood product ratio suggest a 1 : 1 ratio for plasma:pRBC is likely ideal, but prospective studies are needed to further support its use.

SUMMARY

Balanced resuscitation strategies of minimal crystalloid use and early administration of blood products are associated with improved morbidity in paediatric trauma patients but unclear mortality benefit. Current evidence suggests that the utilization of MTPs with 1 : 1 plasma:pRBC ratio may improve morbidity, but more research is needed.

Low Titer Group O Whole Blood In Injured Children Requiring Massive Transfusion

OBJECTIVE

The aim of this study was to assess the survival impact of low-titer group O whole blood (LTOWB) in injured pediatric patients who require massive transfusion.

SUMMARY BACKGROUND DATA

Limited data are available regarding the effectiveness of LTOWB in pediatric trauma.

METHODS

A prospective observational study of children requiring massive transfusion after injury at UPMC Children's Hospital of Pittsburgh, an urban academic pediatric Level 1 trauma center. Injured children ages 1 to 17 years who received a total of >40 mL/kg of LTOWB and/or conventional components over the 24 hours after admission were included. Patient characteristics, blood product utilization and clinical outcomes were analyzed using Kaplan-Meier survival curves, log rank tests and Cox proportional hazards regression analyses. The primary outcome was 28-day survival.

RESULTS

Of patients analyzed, 27 of 80 (33%) received LTOWB as part of their hemostatic resuscitation. The LTOWB group was comparable to the component therapy group on baseline demographic and physiologic parameters except older age, higher body weight, and lower red blood cell and plasma transfusion volumes. After adjusting for age, total blood product volume transfused in 24 hours, admission base deficit, international normalized ratio (INR), and injury severity score (ISS), children who received LTOWB as part of their resuscitation had significantly improved survival at both 72 hours and 28 days post-trauma [adjusted odds ratio (AOR) 0.23, P = 0.009 and AOR 0.41, P = 0.02, respectively]; 6-hour survival was not statistically significant (AOR = 0.51, P = 0.30). Survivors at 28 days in the LTOWB group had reduced hospital LOS, ICU LOS, and ventilator days compared to the CT group.

CONCLUSION

Administration of LTOWB during the hemostatic resuscitation of injured children requiring massive transfusion was independently associated with improved 72-hour and 28-day survival.

Resuscitative practices and the use of low-titer group O whole blood in pediatric trauma

ABSTRACT

Increasing rates of penetrating trauma in the United States makes rapid identification of hemorrhagic shock, coagulopathy, and early initiation of balanced resuscitation in injured children of critical importance. Hemorrhagic shock begins early after injury and can be challenging to identify in children, as hypotension is a late sign that a child is on the verge of circulatory collapse and should be aggressively resuscitated. Recent data support shifting away from crystalloid and toward early resuscitation with blood products because of worse coagulopathy and clinical outcomes in injured patients resuscitated with crystalloid. Multicenter studies have found improved survival in injured children who receive balanced resuscitation with higher fresh frozen plasma: red blood cell ratios. Whole blood is an efficient way to achieve balanced resuscitation in critically injured children with limited intravenous access and decreased exposure to multiple donors. Administration of cold-stored, low-titer O-negative whole blood (LTOWB) appears to be safe in adults and children and may be associated with improved survival in children with life-threatening hemorrhage. Many pediatric centers use RhD-negative LTOWB for all female children because of the risk of hemolytic disease of the fetus and newborn (0-6%); however. there is a scarcity of LTOWB compared with the demand. Low risks of hemolytic disease of the fetus and newborn affecting a future pregnancy must be weighed against high mortality rates in delayed blood product administration in children in hemorrhagic shock. Survey studies involving key stakeholder's opinions on pediatric blood transfusion practices are underway. Existing pediatric-specific literature on trauma resuscitation is often limited and underpowered; multicenter prospective studies are urgently needed to define optimal resuscitation products and practices in injured children in an era of increasing penetrating trauma.

De un centro de trauma a un sistema de trauma en el suroccidente colombiano

Introducción. El objetivo de este estudio fue evaluar el impacto sobre la mortalidad según el perfil de ingreso a un centro de trauma del suroccidente colombiano, como método para entender las dinámicas de atención del paciente con trauma. Métodos. Se realizó un subanálisis del registro de la Sociedad Panamericana de Trauma asociado a un centro de trauma en el suroccidente colombiano. Se analizaron los pacientes atendidos entre los años 2012 y 2021. Se compararon los pacientes con condición de ingreso directo y aquellos que ingresaron remitidos. Se hicieron análisis de poblaciones de interés como pacientes con trauma severo (ISS > 15) y pacientes con/sin trauma craneoencefálico. Se evaluó el impacto de los pacientes remitidos y su condición al ingreso sobre la mortalidad. Resultados. Se incluyeron 10.814 pacientes. La proporción de pacientes remitidos fue del 54,7 %. Los pacientes que ingresaron remitidos presentaron diferencias respecto a la severidad del trauma y compromiso fisiológico al ingreso comparado con los pacientes con ingreso directo. Los pacientes remitidos tienen mayor riesgo de mortalidad (RR: 2,81; IC95% 2,44-3,22); sin embargo, es el estado fisiológico al ingreso lo que impacta en la mortalidad. Conclusión. Los pacientes remitidos de otras instituciones tienen un mayor riesgo de mortalidad, siendo una inequidad en salud que invita a la articulación de actores institucionales en la atención de trauma. Un centro de trauma debe relacionarse con las instituciones asociadas para crear un sistema de trauma que optimice la atención de los pacientes y la oportunidad.

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.

Perspectives on Competencies for Care in Austere Settings

LEVEL OF EVIDENCE

V, Expert Opinion.

Performance of the BIG Score in Predicting Mortality in Normotensive Children With Trauma

OBJECTIVES

Children have a larger reserve for traumatic hemorrhagic shock, requiring a score that uses physiologic variables other than hypotension. Recently, the BIG score comprising admission base deficit, international normalized ratio, and the Glasgow Coma Scale has been reported to predict traumatic mortality. We aimed to validate the performance of the BIG score in mortality prediction of normotensive children with trauma.

METHODS

We reviewed 1046 injured children (<18 years) who visited a Korean academic hospital from 2010 to 2018, excluding those with age-adjusted hypotension. In-hospital mortality, the BIG score and its predicted mortality, Revised Trauma Score, and Pediatric Trauma Score were calculated. We compared areas under the curve (AUCs) for in-hospital mortality of the 3 scores and did in-hospital and BIG-predicted mortalities.

RESULTS

Of the 1046 children, 554 were enrolled with a 4.9% in-hospital mortality rate. The median BIG score was higher in the nonsurvivors (6.4 [interquartile range, 4.4-9.2] vs 20.1 [16.5-24.8]; P < 0.001). The AUC of the BIG score was 0.94 (95% confidence interval [CI], 0.92-0.96), which was higher than that of Pediatric Trauma Score (0.87 [95% CI, 0.84-0.90]; P < 0.001). The AUC of the BIG score tended to be higher than that of Revised Trauma Score without statistical significance (0.90 [95% CI, 0.87-0.92]; P = 0.130). We noted a parallel between in-hospital and BIG-predicted mortalities. The hemorrhage-related nonsurvivors showed higher median base deficit and BIG score than did the isolated traumatic brain injury-related ones.

CONCLUSIONS

The BIG score can predict mortality with excellent accuracy in normotensive children with trauma.

Hemostatic Resuscitation in Children

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

Whole blood hemostatic resuscitation in pediatric trauma: A nationwide propensity-matched analysis

BACKGROUND

Whole blood (WB) has shown promise in pediatric trauma resuscitation following its prominent role in the resuscitation of adult trauma patients. Although WB in children has been shown to be feasible, its effectiveness has yet to be explored. The aim of this study was to examine the outcomes of WB transfusion as an adjunct to component therapy (CT) compared with CT only as early resuscitation for pediatric trauma patients.

METHODS

Children aged 1 to 17 years, who were transfused within 4 hours of presentation, were identified in the Trauma Quality Improvement Program 2017 database. Patients were stratified into those receiving WB-CT versus CT alone. Propensity score matching in a 1:2 ratio was performed based on patient demographics, injury characteristics, hemorrhage control interventions, and trauma center level. The primary outcome measure was patient transfusion requirement. Secondary outcome measures were mortality, hospital length of stay, ventilation days, and major complications.

RESULTS

A total of 135 children receiving WB-CT were matched to 270 patients receiving CT only. Mean (SD) age was 12 (5) years, 66% were male, and the median Injury Severity Score was 32 (range, 20-43). A total of 51% of patients were in shock, 34% had penetrating injuries, and 41% required surgical intervention for hemorrhage control. Total blood products transfused were significantly decreased in children receiving WB, both at 4 hours (35 [22-73] vs. 48 [33-95] mL/kg; p = 0.013) and 24 hours (39 [24-97] vs. 53 [36-119] mL/kg; p < 0.001). Mortality rate at 24 hours (19.3% vs. 21.9%; p = 0.546) and in-hospital mortality (31.1% vs. 34.4%; p = 0.502) were not different. Similarly, no difference in hospital length of stay and rates of major complications was found. Patients in the WB group required significantly less ventilation days (2 [2-6] vs. 3 [2-8] days; p = 0.021).

CONCLUSION

Using WB as an adjunct to CT was associated with decreased transfusion requirements and ventilation days in pediatric trauma patients.

LEVEL OF EVIDENCE

Therapeutic, level III.

Metrics of shock in pediatric trauma patients: A systematic search and review

INTRODUCTION

Shock-index (SI) and systolic blood pressure (SBP) are metrics for identifying children and adults with hemodynamic instability following injury. The purpose of this systematic review was to assess the quality of these metrics as predictors of outcomes following pediatric injury.

MATERIALS AND METHODS

We conducted a literature search in Pubmed, SCOPUS, and CINAHL to identify studies describing the association between shock metrics on the morbidity and mortality of injured children and adolescents. We used the data presented in the studies to calculate the sensitivity and specificity for each metric. This study was registered with Prospero, protocol CRD42020162971.

RESULTS

Fifteen articles met the inclusion criteria. seven studies evaluated SI or SIPA score, an age-corrected version of SI, as predictors of outcomes following pediatric trauma, with one study comparing SIPA score and SBP and one study comparing SI and SBP. The remaining eight studies evaluated SBP as the primary indicator of shock. The median sensitivity for predicting mortality and need for blood transfusion was highest for SI, followed by SIPA, and then SBP. The median specificity for predicting these outcomes was highest for SBP, followed by SIPA, and then SI.

CONCLUSIONS

Common conclusions were that high SIPA scores were more specific than SI and more sensitive than SBP. SIPA score had better discrimination for severely injured children compared to SI and SBP. An elevated SIPA was associated with a greater need for blood transfusion and higher in-hospital mortality. SIPA is specific enough to exclude most patients who do not require a blood transfusion.

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.

Safety profile of low-titer group O whole blood in pediatric patients with massive hemorrhage

BACKGROUND

Low-titer Group O Whole Blood (LTOWB) is used with increasing frequency in adult and pediatric trauma and massive bleeding transfusion protocols. There is a risk of acute hemolytic reactions in non-group O recipients due to the passive transfusion of anti-A and anti-B in the LTOWB. This study investigated the hemolysis risk among pediatric recipients of LTOWB.

STUDY DESIGN AND METHODS

Blood bank records were queried for pediatric recipients of LTOWB between June 2016 and August 2020 and merged with clinical data. The primary outcome was laboratory evidence of hemolysis as manifested by changes in lactate dehydrogenase (LDH), haptoglobin, total bilirubin, reticulocyte count, potassium, and creatinine. Per protocol, these values were collected on hospital days 0-2 for recipients of LTOWB. Transfusion reactions were reported to the hospital's blood bank.

RESULTS

Forty-seven children received LTOWB transfusion between 2016 and 2020; 21 were group O and 26 were non-group O. The groups were comparable in terms of the total volume of transfused blood products, demographics, and clinical outcomes. The most common indication for LTOWB transfusion was hemorrhagic shock due to trauma. There were no clinically or statistically significant differences in baseline, post-transfusion day 1, or post-transfusion day 2 hemolysis markers between the group O and non-group O LTOWB recipients. There were no adverse events or transfusion reactions reported.

DISCUSSION

Use of up to 40 ml/kg of LTOWB appears to be serologically safe for children in hemorrhagic shock.

Adverse events after low titer group O whole blood versus component product transfusion in pediatric trauma patients: A propensity-matched cohort study

BACKGROUND

Low titer group O whole blood (LTOWB) is used as the initial resuscitative fluid in an increasing number of pediatric trauma and massive bleeding transfusion protocols. There is little data on adverse events following its transfusion in pediatric trauma patients.

STUDY DESIGN AND METHODS

Blood bank records were queried for pediatric recipients of at least one unit of red blood cells (RBCs) (component group) or LTOWB (LTOWB group) within 24 h of admission between May 2013 and August 2020. Subjects with early death (<72 h) were excluded. Propensity-score matching of LTOWB and component groups was performed. Adverse events were recorded, including transfusion reaction, thromboembolism, acute kidney injury, sepsis, and organ failure based on PELOD-2 score, along with hospital and ICU length of stay (LOS) and ventilator days.

RESULTS

Thirty-six LTOWB recipients were matched to 36 conventional component recipients. Subjects were 52% male, with blunt injury mechanism (82%), median (IQR) injury severity score = 27 (21-35), and 26% in-hospital mortality. The groups were well matched in terms of demographics and injury characteristics. There were no clinically or statistically significant differences in adverse outcomes including reported transfusion reaction, organ failure, acute kidney injury, sepsis/bacteremia, and venous thromboembolism. Hospital LOS, ventilator days, mortality, and functional disability at discharge were also not significantly different. The LTOWB group had significantly shorter ICU LOS compared to the component group.

CONCLUSION

LTOWB transfusion did not increase the risk of adverse events in children. However, larger studies are required to confirm these results.

Audit of blood product utilization in the care of injured children

BACKGROUND

Blood product utilization in injured children is poorly characterized; the decision to prepare products or transfuse patients can be difficult due to a lack of reliable evidence of transfusion needs across pediatric age-groups and injury types. We conducted an audit of transfusion practices in pediatric trauma based on age, injuries, and mechanism of injury.

METHODS

We reviewed and cross-referenced blood product transfusion practice data from the trauma registry and the anesthesia transfusion record database at a level 1 pediatric trauma center over a 10-year period. Demographic data, injury severity scores, and survival statistics were obtained from the trauma registry. Transfusion rates are reported separately for hospital admission and for intraoperative transfusions for procedures performed during the first two hospital days. Descriptive statistical analysis was used to compare specific groups based on age, injury type, and mechanism of injury.

RESULTS

We report 14 569 trauma admissions of 14 606 patients. The transfusion rate during the admission was 1.56% (227/14 569). 4591 (30.9%) admissions had surgical interventions in first two days of hospitalization with an intraoperative transfusion rate of 2.98%. Patients younger than one year had the highest transfusion rate during admission (2.8%), and the highest transfusion rate during surgical procedures performed in the first two days of the admission (18.87%). Admissions due to vascular injuries had the highest transfusion rates in infancy followed by hollow visceral injuries in adolescents (71.4% and 25%, respectively). Vascular injuries in most age-groups also had high transfusion rates ranging from 11% in 5- to 9-year age-group to 71% in infants. Mechanisms with the highest transfusion rates were firearm wounds in patients older than one year and vehicular accidents for patients younger than one year.

CONCLUSIONS

The overall blood product needs in the pediatric trauma population are low (1.56%). Selected populations requiring higher rates of need include infants younger than one year, and children with thoracic and vascular injuries. Understanding transfusion patterns is important to optimize resource allocation.

Whole Blood is Superior to Component Transfusion for Injured Children: A Propensity Matched Analysis

OBJECTIVE

To compare a propensity-matched cohort of injured children receiving conventional blood component transfusion to injured children receiving low-titer group O negative whole blood.

SUMMARY OF BACKGROUND DATA

Transfusion of whole blood in pediatric trauma patients is feasible and safe. Effectiveness has not been evaluated.

METHODS

Injured children ≥1 years old can receive up to 40 mL/kg of cold-stored, uncrossmatched whole blood during initial hemostatic resuscitation. Whole blood recipients (2016-2019) were compared to a propensity-matched cohort who received at least 1 uncrossmatched red blood cell unit in the trauma bay (2013-2016). Cohorts were matched for age, hypotension, traumatic brain injury, injury mechanism, and need for emergent surgery. Outcomes included time to resolution of base deficit, product volumes transfused, and INR after resuscitation.

RESULTS

Twenty-eight children who received whole blood were matched to 28 children who received components. The whole blood group had faster time to resolution of base deficit [median (IQR) 2 (1-2.5) hours vs 6 (2-24) hours, respectively; P < 0.001]. The post-transfusion INR was decreased in whole blood vs component cohort [median (IQR) 1.4 (1.3-1.5) vs 1.6 (1.4-2.2); P = 0.01]. Lower plasma volumes [median (IQR) = 5 (0-15) mL/kg vs 11 (5-35) mL/kg; P = 0.04] and lower platelet volumes [median (IQR) = 0 (0-2) vs 3 (0-8); P = 0.03] were administered to the whole blood group versus component group. Other clinical variables (in-hospital death, hospital length of stay, intensive care unit length of stay, and ventilator days) did not differ between groups.

CONCLUSIONS

Compared to component transfusion, whole blood transfusion results in faster resolution of shock, lower post-transfusion INR, and decreased component product transfusion. Larger cohorts are required to support these findings.

Timing and volume of crystalloid and blood products in pediatric trauma: An Eastern Association for the Surgery of Trauma multicenter prospective observational study

BACKGROUND

The purpose of this study was to determine the relationship between timing and volume of crystalloid before blood products and mortality, hypothesizing that earlier transfusion and decreased crystalloid before transfusion would be associated with improved outcomes.

METHODS

A multi-institutional prospective observational study of pediatric trauma patients younger than 18 years, transported from the scene of injury with elevated age-adjusted shock index on arrival, was performed from April 2018 to September 2019. Volume and timing of prehospital, emergency department, and initial admission resuscitation were assessed including calculation of 20 ± 10 mL/kg crystalloid boluses overall and before transfusion. Multivariable Cox proportional hazards and logistic regression models identified factors associated with mortality and extended intensive care, ventilator, and hospital days.

RESULTS

In 712 children at 24 trauma centers, mean age was 7.6 years, median (interquartile range) Injury Severity Score was 9 (2-20), and in-hospital mortality was 5.3% (n = 38). There were 311 patients(43.7%) who received at least one crystalloid bolus and 149 (20.9%) who received blood including 65 (9.6%) with massive transfusion activation. Half (53.3%) of patients who received greater than one crystalloid bolus required transfusion. Patients who received blood first (n = 41) had shorter median time to transfusion (19.8 vs. 78.0 minutes, p = 0.005) and less total fluid volume (50.4 vs. 86.6 mL/kg, p = 0.033) than those who received crystalloid first despite similar Injury Severity Score (median, 22 vs. 27, p = 0.40). On multivariable analysis, there was no association with mortality (p = 0.51); however, each crystalloid bolus after the first was incrementally associated with increased odds of extended ventilator, intensive care unit, and hospital days (all p < 0.05). Longer time to transfusion was associated with extended ventilator duration (odds ratio, 1.11; p = 0.04).

CONCLUSION

Resuscitation with greater than one crystalloid bolus was associated with increased need for transfusion and worse outcomes including extended duration of mechanical ventilation and hospitalization in this prospective study. These data support a crystalloid-sparing, early transfusion approach for resuscitation of injured children.

LEVEL OF EVIDENCE

Therapeutic, level IV.

The Israel Defense Forces experience with freeze-dried plasma for the resuscitation of traumatized pediatric patients

BACKGROUND

With the growing recognition of the disadvantages of crystalloid- and colloid-based resuscitation and the advantages of using blood products as the preferred resuscitation fluid, the Israel Defense Forces Medical Corps (IDF-MC) adopted plasma as the primary volume resuscitation regimen in 2013. While data are accumulating for prehospital plasma transfusion, little to no data exist regarding using plasma as a prehospital resuscitation fluid for traumatized pediatric patients.

METHODS

All patients treated by the IDF-MC personnel are recorded in the IDF Trauma Registry, a unique prehospital trauma registry. All patients treated by the IDF advanced life support providers with FDP at the point of injury between April 2013 and June 2018 who were younger than 18 years at the time of injury were included.

RESULTS

Six hundred seventy-nine children were treated by IDF medical providers, of whom 33 (5%) were identified in the IDF Trauma Registry as having received FDP at the point of injury. Most patients (80%) were treated for penetrating injuries. Most patients received one plasma unit. Fifty-four percent of the patients were also treated by Tranexamic Acid (TXA) and 48% were transfused with crystalloids. In 33% of patients, additional life-saving interventions were performed.

CONCLUSION

While the ideal resuscitation fluid for the pediatric population remains to be determined, it seems reasonable to pursue a similar approach to that of applied that for adults. In the IDF-MC, the resuscitation fluid of choice for trauma patients in hemorrhagic shock is freeze-dried plasma transfused at the point of injury. The current study demonstrates the feasibility of FDP administration in the prehospital scenario for injured children and further supports the growing confidence in the use of FDP for the treatment of pediatric trauma patients.

LEVEL OF EVIDENCE

Retrospective descriptive study, level IV.

Cold-stored whole blood platelet function is preserved in injured children with hemorrhagic shock

BACKGROUND

Recent data demonstrate the safety of uncrossmatched cold-stored whole blood (WB) transfusion in pediatric trauma patients. The hemostatic capabilities of platelets within the cold-stored WB unit have been demonstrated via in vitro studies and animal models. However, platelet function has not been evaluated in pediatric recipients of cold-stored WB transfusions.

METHODS

Injured children, 2 years or older and 10 kg or greater with hemorrhagic shock received up to 30 mL/kg of cold-stored, low titer (<50) anti-A and -B, leukoreduced, group O- WB during their initial resuscitation. Patients were included if (1) they received WB and no conventional platelets, and (2) platelet count and thromboelastography maximum amplitude were measured both before and after transfusion. These data and relevant clinical outcomes (mortality, intensive care unit length of stay [LOS], hospital LOS and ventilator days) were compared to a historical cohort of pediatric trauma patients who received uncrossmatched red blood cells (RBC) and conventional room temperature platelets.

RESULTS

Twenty-two children were included in the study; 14 in the component cohort versus 8 in the WB cohort. Neither posttransfusion platelet count (129 × 109/L vs. 135 × 109/L) nor function (thromboelastography maximum amplitude, 59.5 mm vs. 60.2 mm) differed significantly between children receiving cold-stored platelets within the WB unit versus children who received conventional warm platelets. Median (interquartile range) weight-adjusted platelet transfusion volume in the historical cohort was 4.6 (2.5-7.7) mL/kg vs. 2.4 (1.3-4.0) mL/kg in the WB cohort (p = 0.03). There was no difference between groups in age, race, mechanism of injury, Injury Severity Score, vital signs, and severe traumatic brain injury (TBI). Outcomes, including mortality, intensive care unit LOS, hospital LOS, and ventilator days, were not significantly different between groups.

CONCLUSION

No difference was seen in posttransfusion platelet number or function in severely injured children receiving cold-stored WB platelets as compared to those receiving conventional room temperature-stored platelets. Larger cohorts are required to confirm these findings.

LEVEL OF EVIDENCE

Therapeutic, level IV.