Calcium Gluconate Dosing for Hyperkalemia
For treating hyperkalemia, calcium gluconate should be administered at a dose of 10% solution, 15 to 30 mL IV over 2 to 5 minutes. 1
Mechanism and Rationale
Calcium gluconate works by stabilizing myocardial cell membranes, antagonizing the effect of potassium on excitable cell membranes within 1-3 minutes of administration. This provides rapid cardioprotection while other treatments work to lower serum potassium levels. Important points:
- Calcium gluconate contains only 9% elemental calcium (compared to calcium carbonate at 40%) 2
- It does not significantly reduce serum potassium levels but protects against cardiac arrhythmias 1
- Effect begins within 1-3 minutes of administration 1
- If no effect is observed within 5-10 minutes, another dose may be given 1
Administration Guidelines
- Route: Intravenous (IV)
- Concentration: 10% solution
- Dose: 15-30 mL (1.5-3 g) 1
- Rate: Administer over 2-5 minutes 1
- Alternative: Calcium chloride (10%): 5-10 mL (500-1000 mg) IV over 2-5 minutes 1
Complete Hyperkalemia Management Algorithm
Step 1: Stabilize Cardiac Membranes
- Calcium gluconate 10%: 15-30 mL IV over 2-5 minutes 1
- Monitor ECG during administration
- May repeat after 5-10 minutes if ECG changes persist 1
Step 2: Shift Potassium into Cells
- Insulin and glucose: 10 units regular insulin with 25g glucose (50 mL of D50W) IV over 15-30 minutes 1
- Nebulized albuterol: 10-20 mg nebulized over 15 minutes 1
- Sodium bicarbonate: 50 mEq IV over 5 minutes (primarily in patients with metabolic acidosis) 1
Step 3: Promote Potassium Excretion
- Diuretics: furosemide 40-80 mg IV (in patients with adequate renal function) 1
- Potassium binders: 15-50 g plus sorbitol orally or rectally 1
- Dialysis: for severe or refractory hyperkalemia 1
Special Considerations
- Calcium gluconate is preferred over calcium chloride for peripheral administration as it causes less venous irritation 1
- Calcium chloride (10%) may be preferred in cardiac arrest situations due to higher bioavailability 1
- Recent research suggests calcium gluconate is effective primarily for main rhythm disorders due to hyperkalemia but not for non-rhythm ECG disorders 3
- Calcium administration does not lower serum potassium levels; it only temporarily protects against cardiac effects 4
Monitoring
- ECG monitoring during and after calcium administration
- Serial potassium measurements to assess response to treatment
- Watch for signs of hypercalcemia (rare with short-term use)
Pediatric Dosing
For pediatric patients with hyperkalemia, calcium gluconate dosing differs:
- IV/IO: 0.5-1.0 g/kg 1
The treatment of hyperkalemia requires a coordinated approach using multiple agents that work through different mechanisms. Calcium gluconate provides rapid cardioprotection while other therapies work to reduce serum potassium levels.