(1568) Clinical Assessment of Low Calcium In traUMa (CALCIUM): An Interim Analysis

Introduction: Hypocalcemia occurs after blood transfusions due to the preservatives in blood products. Recent data suggest that traumatic injury is an independent risk factor for hypocalcemia. Calcium is critical to physiologic cellular function, myocardial conduction and contractility, and vascular tone. Thus, calcium derangements can result in hypotension, dysrhythmias, hypotension, and coagulopathy. The objective of this study was to determine the incidence of hypocalcemia in trauma patients on arrival to the hospital and if calcium derangement are associated with decreased survival.

Methods: A prospective, observational, multicenter study is being conducted at three level I trauma centers – Brooke Army Medical Center, University Hospital at the University of Texas Health-San Antonio, and University of Colorado Hospital. Inclusion criteria included patients with ‘major’ trauma activations. Research personnel prospectively extracted the data on ionized calcium levels at 0, 3, 6, 12, 18, and 24 hours after arrival to the emergency department along with blood, medications, and fluids infused within the first 24 hours. The primary outcome was incidence of hypocalcemia within the first 24 hours. Secondarily, we sought to explain the relationship between both hypo- and hypercalcemia and survival.

Results: This study remains ongoing. Interim analysis demonstrates data from one of the centers; the other two are currently enrolling but data has not yet been aggregated. We collected a total of 534 subjects with iCa observations over 24 hours. Of those, 109 (20%) subjects had at least one iCa value reach hypocalcemic levels ( < 1.1mmol/L) in the first 24 hours. Of those, 23 (21%) died. Subjects that maintained their calcium levels within normal limits had the best prognosis, whereas hypercalcemia portended the worst outcomes followed by those with hypocalcemia at both 48-hours and 30 days on Kaplan-Meier analysis (p < 0.0001). A similar U-shaped curve was noted for 1-hour mortality, 24-hour mortality, 30-day mortality, and coagulopathy.

Conclusions: This study will provide data further elucidating the potential impact of calcium derangements on overall mortality from trauma and could guide early/prehospital interventions, potentially improving survival after traumatic injury.