A trauma patient has received 14 units of packed red cells and 12 units of fresh frozen plasma over 3 hours. He develops prolongation of the QT interval on ECG, reduced cardiac contractility, and vasoplegia unresponsive to noradrenaline. Ionised calcium is 0.72 mmol/L. The most appropriate immediate treatment is:

• A Sodium bicarbonate infusion
• B Intravenous magnesium sulphate 2 g
• C Intravenous calcium chloride 10 mL of 10% solution ✓
• D Insulin-dextrose infusion

Explanation

Citrate anticoagulant in transfused blood chelates ionised calcium, and impaired hepatic metabolism under shock and hypothermia worsens accumulation. Hypocalcaemia causes QT prolongation, negative inotropy and refractory vasoplegia. Treatment is intravenous calcium, preferably calcium chloride via a central line because it delivers three times the elemental calcium of gluconate and does not depend on hepatic conversion. Magnesium, bicarbonate and insulin address other electrolyte problems and would not correct citrate toxicity.

Reference: Morgan and Mikhail's Clinical Anesthesiology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.