Association of blood product ratios with early mortality in pediatric trauma resuscitation: A time-dependent analysis from the National Trauma Databank

BACKGROUND: Injured children with severe hemorrhage often receive blood product transfusions with ratios of plasma and platelets to packed red blood cells (PRBCs) approaching 1:1:1. Whether blood product ratios vary during pediatric resuscitation is unknown. This study (1) described precise timing of pediatric blood product administration, (2) characterized changes in blood product ratios over time, and (3) evaluated the association of blood products with early mortality while incorporating time-varying factors. METHODS: Pediatric (younger than 18 years) trauma patients receiving high-volume transfusion (>40 mL/kg total products or >2 U PRBC or whole blood, during first 4 hours) were obtained from the 2017 to 2019 Trauma Quality Improvement Program database. The time of each individual product transfusion was recorded, along with demographics, injury details, and times of death. Patients were assigned to blood product groups at 15-minute intervals: high plasma/PRBC ratio (>1:1) with platelets, high plasma/PRBC ratio (>1:1) without platelets, low plasma/PRBC ratio (<1:1), PRBC only, and whole blood. Cox proportional hazards modeling for 24-hour mortality was performed, including blood product group as a time-varying variable and adjusting for relevant covariates. RESULTS: Of 1,152 included patients (median age, 15 years; 32% penetrating, 28% severe traumatic brain injury [sTBI]), 18% died within 24 hours. During the resuscitation period, the number of patients in high-ratio groups increased over time, and patients switched blood product groups up to six times. There was no significant difference in mortality by blood product group. Among patients with sTBI, there was a strong trend toward lower mortality among high plasma/PRBC without platelets versus high plasma/PRBC with platelets (hazard ratio, 0.55; p = 0.07). CONCLUSION: No significant association of high ratios or whole blood with mortality was seen when time-varying factors were incorporated. The impact of balanced resuscitation strategies, particularly platelet transfusion, may be greatest among patients with sTBI. Optimizing balanced resuscitation for children requires appropriately designed prospective studies. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.