A patient with PPH receives 4 units of packed red blood cells. She develops perioral numbness and carpopedal spasm. The most likely cause is:
- A Hypokalemia
- B Hyperkalemia
- C Hypocalcemia due to citrate toxicity ✓
- D Hypomagnesemia
Correct answer: C. Hypocalcemia due to citrate toxicity
Explanation
Massive blood transfusion leads to citrate toxicity. Citrate binds calcium, causing hypocalcemia manifesting as perioral numbness and carpopedal spasm. Hypokalemia causes muscle weakness. Hyperkalemia causes cardiac arrhythmias. Hypomagnesemia causes neuromuscular irritability but is less common in this setting.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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