The effects of hypocalcemia in severely injured pediatric trauma patients

INTRODUCTION The role of calcium is ubiquitous in human physiology. Emerging evidence suggests that the lethal triad be revised to include hypocalcemia (hypoCa) and thus be known as the lethal diamond. There are data showing that traumatic injury may result in hypoCa independent from the mechanism of calcium chelation by citrate-based blood preservatives. Minimal literature exists analyzing the role of hypoCa in pediatric trauma patients. We hypothesize that there is an independent association of hypoCa with increased blood product requirements and mortality. METHODS A retrospective cohort study of severely injured pediatric trauma patients was conducted. Trauma registry data were collected from January 2016 to August 2021. Ionized calcium (iCa) levels were obtained from arrival blood draws. Subjects were categorized into two groups by a threshold iCa level of 1.00 mmol/L and compared. Shock Index Pediatric Adjusted scores were used to adjust for age-specific differences in vital signs. RESULTS A total of 142 patients were compared, of which 46.5% were hypocalcemic (iCa <1.00 mmol/L). Patients were well matched in terms of demographics and injury severity. The hypocalcemic group had lower systolic blood pressure and a higher percentage of Shock Index Pediatric Adjusted-positive patients. Weight-adjusted transfusion volumes were significantly higher in the hypocalcemic group at both the 4-hour and 24-hour time points without a difference in prehospital transfusion requirements. There was no observed difference in early or in-hospital mortality. CONCLUSION This study contributes to the body of literature regarding the association between hypoCa and traumatic injury in the pediatric population. Hypocalcemia was associated with increased blood product requirements without a difference in prehospital transfusion requirements, suggesting a possible independent association. Further prospective studies are needed to better understand this relationship. LEVEL OF EVIDENCE Therapeutic/Care Management; Level IV.