729 - Transfusion-Associated Hypocalcemia in Pediatric Trauma: A Hidden Variable in Emergency Care

Publication Number: 3705.729

Lindsay J. Ercole, UPMC Childrens Hospital of Pittsburgh, Pittsburgh, PA, United States; Raymond Pitetti, UPMC Childrens Hospital of Pittsburgh, Pittsburgh, PA, United States

Background: Trauma is the leading cause of morbidity and mortality among children. While adult studies have highlighted hypocalcemia as a critical factor during trauma resuscitation, data on its incidence and clinical implications in pediatric patients remains limited.

Objective: This study aims to characterize the incidence of hypocalcemia before and after transfusion in pediatric trauma patients and to evaluate trends in calcium levels during blood product administration.

Design/Methods: This retrospective cohort study was conducted at a single Level I pediatric trauma center from 2015 to 2021. IRB approval obtained under exempt status per institutional guidelines. Patients aged 0 to 21 years who presented as Level I, II, or III trauma, received blood products during emergency department (ED) resuscitation (defined as whole blood, packed red blood cells, or both), and had available laboratory data were included. Ionized calcium (iCal) and serum calcium (Ca) values were extracted from institutional data sources and categorized as low, normal, or high. The primary outcome was the incidence of hypocalcemia before and after transfusion. Secondary outcomes included the change in calcium levels and mortality.

Results: In the transfusion cohort, 59 patients who received blood products had paired serum calcium values pre- and post-transfusion. Of the pediatric trauma patients that did not require transfusion, 7808 pediatric trauma patients were identified. 20.3% had low ionized calcium on presentation, compared to 58% in the transfused group. The median ionized calcium in transfused patients was 1.1 mmol/L, versus 1.25 mmol/L in controls. Within the transfusion subset of 59 patients that had paired serum calcium values, median levels decreased from 8.10 mg/dL pre-infusion to 7.90 mg/dL post-infusion. There was a statistically significant directional change (Z = -1.888, p = 0.059) found between pre and post transfusion values. While categorical changes were not statistically significant, a trend toward decreased calcium post-transfusion was observed.

Conclusion(s): Hypocalcemia is prevalent among pediatric trauma patients in this sample. Over half of transfused patients presenting with an initial low ionized calcium. Calcium levels modestly declined following transfusion, suggesting a potential clinical impact. While the mechanism behind this change is not yet understood, larger sample sizes and multi-site data could elucidate trends. Further research is needed to understand the implications of hypocalcemia on clinical outcomes and to inform resuscitation in pediatric trauma.

Table 1 Demographics
Above find the breakdown of patients who had serum calcium values available pre and post transfusion.

Shift in Serum Calcium Concentrations with Transfusion
This graph shows the distribution of hypocalcemia, hypercalcemia, and normal serum values among pediatric trauma patients prior to transfusion (left). The right sided graph represents the redistribution of serum calcium values following transfusion. Following blood product administration, there is an observed trend of transitioning to the abnormal categorization. This highlights an area of further study needed to better understand the mechanism.