A 52-year-old man undergoes liver transplantation and receives 18 units of packed red cells and 14 units of fresh frozen plasma. At reperfusion he develops perioral tingling, carpopedal spasm, and prolongation of the QT interval. Ionised calcium is 0.78 mmol/L. The most appropriate immediate treatment is:
- A Intravenous calcium chloride or calcium gluconate ✓
- B Intravenous magnesium sulphate
- C Sodium bicarbonate infusion
- D Additional fresh frozen plasma
Correct answer: A. Intravenous calcium chloride or calcium gluconate
Explanation
Citrate in anticoagulated blood products chelates ionised calcium. Massive transfusion, especially with impaired hepatic metabolism of citrate as in liver failure or transplant, produces symptomatic hypocalcaemia with neuromuscular irritability and QT prolongation. Treatment is intravenous calcium, guided by serial ionised calcium levels. Magnesium treats torsades from hypomagnesaemia but will not correct citrate-induced hypocalcaemia. Bicarbonate worsens ionised hypocalcaemia by increasing protein binding, and extra plasma adds more citrate load.
Reference: Miller's Anesthesia, 9th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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