Prevalence and Outcomes of High versus Low Ratio Plasma to Red Blood Cell Resuscitation in a Multi-Institutional Cohort of Severely Injured Children.

BACKGROUND: The benefit of targeting high ratio fresh frozen plasma (FFP):red blood cell (RBC) transfusion in pediatric trauma resuscitation is unclear as existing studies are limited to patients who retrospectively met criteria for massive transfusion. The purpose of this study is to evaluate the use of high ratio FFP:RBC transfusion and the association with outcomes in children presenting in shock. METHODS: A post-hoc analysis of a 24-institution prospective observational study (4/2018-9/2019) of injured children <18 years with elevated age-adjusted shock index was performed. Patients transfused within 24 hours were stratified into cohorts of low (<1:2) or high (>1:2) ratio FFP:RBC. Nonparametric Kruskal-Wallis and chi-square were used to compare characteristics and mortality. Competing risks analysis was used to compare extended (≥75th percentile) ventilator, intensive care, and hospital days while accounting for early deaths. RESULTS: Of 135 children with median (IQR) age 10 (5,14) years and weight 40 (20,64) kg, 85 (63%) received low ratio transfusion and 50 (37%) high ratio despite similar activation of institutional massive transfusion protocols (MTP; low-38%, high-46%, p = .34). Most patients sustained blunt injuries (70%). Median injury severity score was greater in high ratio patients (low-25, high-33, p = .01); however, hospital mortality was similar (low-24%, high-20%, p = .65) as was the risk of extended ventilator, ICU, and hospital days (all p > .05). CONCLUSION: Despite increased injury severity, patients who received a high ratio of FFP:RBC had comparable rates of mortality. These data suggest high ratio FFP:RBC resuscitation is not associated with worst outcomes in children who present in shock. MTP activation was not associated with receipt of high ratio transfusion, suggesting variability in MTP between centers. LEVEL OF EVIDENCE: Prospective cohort study, Level II.

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.

Cold-stored whole blood: A better method of trauma resuscitation?

BACKGROUND: Cold-stored whole blood (CWB) provides a balance of red blood cells, plasma, and platelets in less anticoagulant volume than standard blood component therapy (BCT). We hypothesize that patients receiving CWB along with BCT have improved survival compared with patients receiving only BCT. METHODS: We performed a dual-center case-match study of trauma patients who received CWB and BCT at two urban, Level-I Trauma Centers. Criteria to receive CWB included boys 16 years of older, women older than 50 years, SBP less than 90 mm Hg, and identifiable source of hemorrhage. We performed a 2:1 propensity match against any trauma patient who received 1 unit or greater of packed red cells during their initial trauma bay resuscitation. Endpoints included trauma bay mortality, 30-day mortality, laboratory values at 4 hours and 24 hours, and overall blood product utilization. Comparisons were made with Wilcoxon-ranked sum and Fisher's exact test, p less than 0.05 was significant. RESULTS: Between both institutions, a total of 107 patients received CWB during the study period with 91 being matched to 182 BCT patients for analysis. Hemodynamic parameters of the patients in both groups at the time of presentation were similar. The CWB patients had higher mean hemoglobin (10 ± 2 g/dL vs. 11 ± 2 g/dL; p < 0.001) and hematocrit (29.2 ± 6.1% vs. 32.1 ± 5.8%; p < 0.001) at 24 hours. Importantly, trauma bay mortality was less in CWB patients (8.8% vs. 2.2%;p = 0.039). Thirty-day mortality was not different in CWB patients, and there were no differences in the total amount of blood products transfused at the 4-hour and 24-hour periods. CONCLUSION: Cold-stored whole blood offers the benefit of a balanced resuscitation with improved trauma bay survival and higher mean hemoglobin at 24 hours. A larger, prospective study is needed to determine whether it has a longer-term survival benefit for severely injured patients. LEVEL OF EVIDENCE: Therapeutic, level III.