USAF School of Aerospace Medicine Wright-Patterson AFB United States
Uncontrolled hemorrhage is the leading cause of preventable mortality in trauma. Rapid identification of patients requiring blood transfusion during assessment and resuscitation is necessary for mortality reduction. Most pre-hospital or field medical criteria used to predict blood product needs in trauma patients rely on a combination of physiological, anatomic, and mechanism-of-injury components. Calcium Ca activates protein kinase C and is required for coagulation factors to bind properly in the clotting cascade. Ca has presented a novel laboratory test to predict early blood transfusion. The purpose of this study was to identify a relationship between serum Ca levels and the need for early transfusion. In this retrospective analysis, serum Ca 7.9 mgdL was strongly associated with the need for blood product transfusion, as well as transfusion of more than four units within 4 hours, even after controlling for other clinical variables. This effect was age specific for the subject group aged 40 years and below. Patients with normal blood pressure could give medical teams a false sense of patient stability. Younger patients have a compensating capacity with blood loss and will not show signs of shock until they have exhausted this mechanism.