Effect of ionized calcium level on short-term prognosis in severe multiple trauma patients: a clinical study.

Background: Hypocalcemia has been reported as an independent predictor of trauma mortality. We investigated the relationship between temporal variations in blood ionized calcium concentration (iCa) and prognosis in severe trauma patients who underwent massive transfusion protocol (MTP). Methods: This single-center, retrospective, observational study investigated 117 severe trauma patients treated with MTP in the Department of Emergency Medicine and Critical Care, Saitama Medical Center, Saitama Medical University, between March 2013 and March 2019. Multivariate logistic regression analysis was performed, assigning pH-corrected initial and minimum blood ionized calcium concentration within 24 hours of admission (iCa_min), age, initial systolic blood pressure and Glasgow Coma Scale (GCS) score, and incidence of Ca supplementation as independent variables and 28-day mortality as dependent variable. Results: The logistic regression analysis identified iCa_min (adjusted OR 0.03, 95% CI 0.002 to 0.4), age (adjusted OR 1.05, 95% CI 1.02 to 1.09), and GCS score (adjusted OR 0.84, 95% CI 0.74 to 0.94) as significant independent predictors of 28-day mortality. The receiver operating characteristic analysis identified optimal cut-off value of iCa_min for predicting 28-day mortality as 0.95 mmoL/L (area under the curve 0.74). Conclusion: In the management of patients with traumatic hemorrhagic shock, aggressive correction of the iCa to maintain 0.95 mmol/L or higher within 24 hours of admission may improve short-term outcomes. Level of evidence: Therapeutic/care management, level III.