Hypocalcemia is a problem in most actively bleeding trauma patients on presentation, and administration of even one unit of citrated blood product can further lower ionized calcium to levels approaching critical values (<0.9mmol/l). One gram of calcium IV/IO should be given to patients in hemorrhagic shock during or immediately after transfusion of the first unit of blood product and with ongoing resuscitation after every 4 units of blood products. At a minimum, one gram of calcium should be administered after no more than 4 units of blood product have been infused to avoid citrate toxicity. Ideally, ionized calcium should be monitored and calcium should be given for ionized calcium less than 1.2mmol/L. This should be done at the first level of care capable of monitoring these patients, typically a Role 2 equivalent or above. Appropriate calcium solutions should otherwise be administered per protocol for signs and symptoms of hypocalcemia (e.g., prolonged QTc, ventricular arrhythmias, decreased cardiac output/cardiovascular collapse, coagulopathy, tetany, laryngospasm, seizures, and paresthesia)