What is the treatment for hypocalcemia?

Treatment of Hypocalcemia

For symptomatic hypocalcemia, immediate intravenous calcium administration is the first-line treatment, with calcium gluconate (50-100 mg/kg) preferred over calcium chloride due to less vessel irritation. 1, 2, 3

Assessment and Classification

Severity Assessment:

• Symptomatic hypocalcemia: Presents with neuromuscular irritability, tetany, seizures, cardiac arrhythmias, or prolonged QT interval
• Asymptomatic hypocalcemia: Detected on laboratory tests without clinical manifestations

Common Causes:

• Hypoparathyroidism (surgical or primary)
• Vitamin D deficiency
• Tumor lysis syndrome
• Massive blood transfusion (citrate toxicity)
• Acute pancreatitis
• Magnesium deficiency
• Medication-induced

Treatment Algorithm

Acute Symptomatic Hypocalcemia:

1. Immediate IV Calcium:

   • First choice: Calcium gluconate 50-100 mg/kg IV administered slowly with ECG monitoring 1, 2
   • Alternative: Calcium chloride 10% solution (provides more elemental calcium but more irritating to veins) 4, 3

2. Administration Considerations:

   • Administer into large veins or via central line to prevent extravasation and tissue necrosis 5
   • Slow infusion with continuous ECG monitoring for bradycardia 1
   • For critically ill trauma patients, an infusion of 4g calcium gluconate at 1g/hour has shown 95% success in correcting moderate to severe hypocalcemia 6

3. Concurrent Electrolyte Management:

   • Check and correct magnesium levels if low 1
   • Monitor phosphate levels - high phosphate increases risk of calcium phosphate precipitation 1
   • Consider renal consultation if phosphate levels are high 1

Chronic Hypocalcemia Management:

1. Oral Calcium Supplementation:

   • Calcium carbonate or calcium citrate (avoid calcium carbonate in patients with elevated calcium levels) 1

2. Vitamin D Therapy:

   • For mild-moderate cases: Daily vitamin D supplementation 1
   • For severe/refractory cases: Active vitamin D metabolites (calcitriol 20-30 ng/kg daily or alfacalcidol 30-50 ng/kg daily) 1

3. Special Considerations:

   • In CKD patients: Balance correction of hypocalcemia with risk of vascular calcification 1
   • In tumor lysis syndrome: Cautious calcium replacement to avoid calcium phosphate precipitation 1
   • In patients with 22q11.2 deletion syndrome: Regular calcium monitoring, especially during biological stress 1

Monitoring and Follow-up

• Regular monitoring of serum calcium, phosphate, magnesium, and PTH levels
• ECG monitoring during acute IV calcium administration
• Targeted calcium monitoring during vulnerable periods (perioperatively, during acute illness) 1
• Monitor for signs of overcorrection (hypercalcemia, renal calculi) 1

Cautions and Pitfalls

1. Avoid rapid correction in chronic hypocalcemia to prevent complications
2. Never administer calcium and sodium bicarbonate through the same line due to precipitation risk 1
3. Caution with calcium administration when phosphate levels are high due to risk of calcium phosphate precipitation in tissues 1
4. Monitor for extravasation during IV calcium administration to prevent skin necrosis 5
5. Avoid overcorrection which can lead to iatrogenic hypercalcemia, renal calculi, and renal failure 1

In patients with chronic kidney disease, individualized approaches to hypocalcemia treatment are needed, as aggressive correction may not always be beneficial, particularly in those receiving calcimimetics 1.