Early hypocalcemia in severe trauma*

OBJECTIVES: We tested the hypothesis that colloid-induced hemodilution can induce hypocalcemia in the early phase of severe trauma resuscitation and tried to assess other potential causative factors of that hypocalcemia. DESIGN: Prospective cohort. SETTING: Level I academic trauma center. PATIENTS: Consecutive severe trauma patients (n = 212, mean Injury Severity Score 34) resuscitated in the prehospital phase without any blood transfusion. INTERVENTIONS: At admission, ionized calcium (corrected to an arterial pH = 7.40) was measured. MEASUREMENTS AND MAIN RESULTS: Hypocalcemia was defined as a value 15%) between calculated and observed ionized calcium, and these patients had more severe trauma and more frequently had acidosis and/or prehospital cardiac arrest. Using the TRISS methodology, survival was not significantly different from that expected in this trauma population. CONCLUSION: Hypocalcemia frequently occurs on arrival at the hospital in severe trauma patients, and colloid-induced hemodilution and severe shock and/or ischemia-reperfusion appear to be important causative factors.