From the Guidelines
Calcium gluconate infusion should be administered at a concentration of 10-20 mg/mL (1-2%) through a central venous catheter when possible, with a recommended dose of 1-2 grams of calcium gluconate (equivalent to 90-180 mg of elemental calcium) in 50-100 mL of compatible solution over 10-20 minutes for acute hypocalcemia, and 0.5-2 mg/kg/hour of elemental calcium for maintenance therapy, as supported by the most recent and highest quality study 1.
Key Considerations
- For acute hypocalcemia, the infusion rate should be adjusted to maintain ionized calcium within the normal range (1.1-1.3 mmol/L) 1.
- Patients should be on continuous cardiac monitoring during infusion as rapid administration can cause bradycardia, hypotension, or cardiac arrhythmias 1.
- Avoid mixing calcium with bicarbonate or phosphate solutions to prevent precipitation 1.
- Calcium gluconate is preferred over calcium chloride for most patients as it causes less tissue irritation if extravasation occurs 1.
Administration Guidelines
- Monitor serum calcium levels every 4-6 hours during acute treatment, adjusting the rate to maintain ionized calcium within normal range (1.1-1.3 mmol/L) 1.
- The infusion works by directly increasing serum calcium levels, which is essential for nerve conduction, muscle contraction, blood coagulation, and numerous enzymatic processes throughout the body.
Special Considerations
- In patients who undergo parathyroidectomy, the blood level of ionized calcium should be measured every 4 to 6 hours for the first 48 to 72 hours after surgery, and then twice daily until stable, with calcium gluconate infusion initiated at a rate of 1 to 2 mg elemental calcium per kilogram body weight per hour if necessary 1.
From the FDA Drug Label
2 DOSAGE & ADMINISTRATION 2.1 Important Administration Instructions Calcium Gluconate Injection contains 100 mg of calcium gluconate per mL which contains 9.3 mg (i.e., 0.465 mEq) of elemental calcium. Dilute Calcium Gluconate Injection prior to use in 5% dextrose or normal saline and assess for potential drug or IV fluid incompatibilities [see Dosage and Administration (2. 5)].
For bolus intravenous administration: Dilute the dose [see Dosage and Administration (2. 2)] of Calcium Gluconate Injection in 5% dextrose or normal saline to a concentration of 10-50 mg/mL prior to administration. Administer the dose slowly and DO NOT exceed an infusion rate of 200 mg/minute in adults or 100 mg/minute in pediatric patients, including neonates. For continuous intravenous infusion: Dilute Calcium Gluconate Injection in 5% dextrose or normal saline to a concentration of 5.8-10 mg/mL prior to administration. Administer at the rate recommended in Table 1 [see Dosage and Administration (2.2)] and monitor patients, vitals, calcium and ECG during the infusion [see Warnings and Precautions ( 5-5. 4)].
The calcium gluconate infusion protocol involves:
- Diluting the injection in 5% dextrose or normal saline
- Administering the dose slowly
- Not exceeding an infusion rate of 200 mg/minute in adults or 100 mg/minute in pediatric patients
- Monitoring patients, vitals, calcium, and ECG during the infusion
- Using a secure intravenous line to avoid calcinosis cutis and tissue necrosis 2
From the Research
Calcium Gluconate Infusion Protocol
- The treatment of moderate to severe acute hypocalcemia in critically ill trauma patients can be achieved with an infusion of 4 g of calcium gluconate, as shown in a study published in 2007 3.
- This dosage regimen was successful for achieving a serum ionized calcium (iCa) >1 mmol/L for 19 of 20 (95%) hypocalcemic patients and achieved a concentration >1.12 mmol/L in 14 (70%) of the patients.
- For severe hypocalcemia, the Society for Endocrinology Clinical Committee recommends administering 10–20 mL 10% calcium gluconate in 50–100 mL of 5% dextrose i.v. over 10 min with ECG monitoring, followed by a calcium gluconate infusion at 50–100 mL/h 4.
- The infusion rate can be titrated to achieve normocalcaemia and continued until treatment of the underlying cause has taken effect 4.
- Calcium chloride can be used as an alternative to calcium gluconate, but it is more irritant to veins and should only be given via a central line, with a dose equivalence of 4.4 mL of 7.35% calcium chloride or 2.2 mL of 14.7% calcium chloride for i.v. administration equivalent to 10 mL of 10% calcium gluconate 4.
Key Considerations
- Intravenous calcium infusion is essential to raise calcium levels and resolve or minimize symptoms in the setting of acute hypocalcemia 5.
- Oral calcium and/or vitamin D supplementation is the most frequently used treatment for chronic hypocalcemia 5.
- The development of long-acting recombinant human PTH may modify the management of chronic hypoparathyroidism in the future 5.
- Measurement of ionized Ca+2 is the preferred way to ascertain the diagnosis of hypocalcemia and hypercalcemia 6.