What is the prehospital treatment for hypocalcemia?

Prehospital Treatment for Hypocalcemia

The preferred prehospital treatment for hypocalcemia is intravenous calcium chloride at a dose of 20 mg/kg (0.2 mL/kg for 10% CaCl2) administered by slow push for cardiac arrest or infused over 30-60 minutes for other indications. 1

Assessment and Recognition

• Monitor for symptoms of hypocalcemia:

  • Neuromuscular irritability
  • Tetany
  • Seizures
  • Cardiac dysrhythmias (especially when ionized Ca²⁺ levels fall below 0.8 mmol/L)
  • Decreased cardiac contractility
  • Impaired systemic vascular resistance

• High-risk scenarios in prehospital setting:

  • Trauma patients receiving blood transfusions
  • Massive transfusion situations
  • Patients with known hypocalcemia

Treatment Protocol

First-Line Treatment:

• Calcium Chloride (10% solution)
  • Dosage: 20 mg/kg (0.2 mL/kg) IV/IO 1
  • Administration:
    • For cardiac arrest: Give by slow push
    • For other indications: Infuse over 30-60 minutes
    • Monitor heart rate during administration
    • Stop injection if symptomatic bradycardia occurs

Alternative Treatment:

• Calcium Gluconate (10% solution)
  • Dosage: 60 mg/kg IV/IO 1
  • Use only if calcium chloride is unavailable
  • Less effective due to lower elemental calcium content

Important Considerations

Route of Administration

• Central venous access is preferred when available 1
• Extravasation through peripheral IV can cause severe skin and soft tissue injury

Calcium Chloride vs. Calcium Gluconate

• Calcium chloride contains more elemental calcium (10 mL of 10% CaCl₂ contains 270 mg elemental calcium) 1
• Calcium gluconate contains less (10 mL of 10% calcium gluconate contains only 90 mg elemental calcium) 1
• Calcium chloride results in more rapid increase in ionized calcium concentration 1
• Calcium chloride is preferred for critically ill patients 1

Monitoring

• Monitor ionized calcium levels when possible
• Target normal range of ionized calcium (1.1-1.3 mmol/L) 1
• Transfusion-induced hypocalcemia with ionized Ca²⁺ levels below 0.9 mmol/L should be corrected promptly 1

Special Situations

• In trauma patients with massive transfusion:
  • Hypocalcemia is common due to citrate in blood products chelating calcium 1
  • Each unit of blood product contains approximately 3g of citrate 1
  • Liver dysfunction from shock impairs citrate metabolism, worsening hypocalcemia 1

Cautions

• Do not mix calcium chloride with sodium bicarbonate 1
• Do not mix with vasoactive amines 1
• Monitor for hypercalcemia, especially with higher doses
• Calcium chloride is more irritating to veins than calcium gluconate

Efficacy Considerations

• Calcium chloride is preferred in liver dysfunction as decreased citrate metabolism results in slower release of ionized calcium from calcium gluconate 1
• For moderate to severe hypocalcemia (ionized Ca²⁺ <1.0 mmol/L), higher doses may be required 2