Massive transfusion refers to usage of 10 or more units of red blood cells in less than 24 hours.
Massive transfusion is generally related to trauma.
Massive transfusion can lead to a coagulopathy secondary to the dilution of clotting factors and platelets, and be secondary to hypothermia, and hypofibrinogenemia.
Massively transfused patients frequently receive crystalloid fluids along with units of uncrossed matched type O blood leading to dilution of clotting proteins, platelets and fibrinogen.
Hypothermia is due to transfusion or for treated, and recently thawed blood products, and contributes to coagulopathy.
Hypocalcemia may result from infusion of large infusions of blood containing citrate anticoagulant.
Hyperkalemia may result from leakage of red cells during storage.