32M BIBEMS s/p SW to abdomen. He becomes hypotensive/tachycardic, becomes less responsive. Massive transfusion protocol is initiated.
- What electrolyte abnormality is caused by massive transfusion?
- In the 1:1:1 ratio, are we talking about a single dose of platelets or a single unit of platelets?
1) Due to large quantity of citrate being administered (~3g citrate per unit of RBC), massive transfusion can lead:
- Hypocalcemia – Citrate binds to ionized calcium. Look out for signs of hypocalcemia including tetany, hypotension, prolonged QTc. Monitor ionized calcium level
- Hyperkalemia (especially if using older blood and in patients with CKD)
- Metabolic alkalosis (citrate metabolism produces HCO3)
*Citrate is metabolized by the liver, so inc risk in patients with hepatic dysfunction.
2) The 1:1:1 refers to Plasma:PLT:RBC where the PLT is measured in units
- 1 adult dose of platelets = 1 unit of apheresis platelets = 5-6 units of random donor platelet units
(i.e. 6U plasma:1 dose of platelets:6U RBCs)
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Sources:
- Holcomb et al. Transfusion of plasma, platelets, and red blood cells in a 1:1:1 vs a 1:1:2 ratio and mortality in patients with severe trauma. JAMA. 2015;313(5):471-482.
- http://www.trauma.org/archive/resus/massive.html
- Spinella PC, Holcomb JB. Resuscitation and transfusion principles for traumatic hemorrhagic shock. Blood Rev. 2009 Nov;23(6):231-40.