A trauma patient may develop hypocalcemia, especially after massive transfusion. This can worsen outcomes.

Causes of hypocalcemia:

(1) trauma-related hypocalcemia, associated with calcium loss if bleeding

(2) transfusion-related hypocalcemia, due to citrate in blood products


Ionized calcium reflects calcium status better than the total calcium. An ionized calcium < 1.12 mmol/L indicates hypocalcemia, and a value < 0.90 mmol/L indicates severe hypocalcemia.


Hypocalcemia may exacerbate and be exacerbated by the "lethal triad":

(1) hypothermia

(2) acidosis

(3) coagulopathy

Ditzel et al referred the triad plus hypocalcemia as a "lethal diamond".


Administration of intravenous calcium chloride can reduce the hypocalcemia.

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