Critical Care Medicine-Renal, Electrolyte and Acid Base Disorders>>>>>Calcium, Phosphate, and Magnesium
Question 1#

A 32-year-old G2P1 female at 34 weeks gestation and a history of chronic kidney disease develops hypertension and altered mental status followed by seizures. She is started on intravenous magnesium with seizure resolution. She becomes somnolent 3 hours later, and physical examination reveals hyporeflexia.

What is the immediate management for this symptom?

A. Hypotonic IV fluids
B. Calcium gluconate infusion
C. Hemodialysis
D. Furosemide

Correct Answer is B


Correct Answer: B

The signs and symptoms elicited by this patient are consistent with hypermagnesemia. This patient is predisposed to higher levels of serum magnesium due to underlying renal impairment. Although hemodialysis will be the most definitive management for removing magnesium from the system in this patient with chronic kidney disease, immediate and first-line management of central nervous system and cardiac side effects should be by administration of IV calcium which acts as a magnesium antagonist. Unless the patient is anuric, medical management with intravenous fluids and loop diuretics should also be initiated (choice D) after giving calcium, especially in severe or symptomatic cases. 


  1. Mordes JP, Wacker WE. Excess magnesium. Pharmacol Rev. 1977;29(4):273-300.