How to manage acute hyperkalemia?

Management of Acute Hyperkalemia

For a patient with acute hyperkalemia who went from 4.3 to 5.3 mEq/L in one day, immediate treatment with calcium gluconate 10% (15-30 mL IV over 2-5 minutes) is recommended to stabilize the cardiac membrane, followed by insulin with glucose (10 units regular insulin IV with 50 mL of 25% dextrose) to shift potassium into cells. 1

Step-by-Step Management Algorithm

1. Assess Severity and Cardiac Risk

• Check for ECG changes: At 5.3 mEq/L, look for early signs like peaked/tented T waves 1
• Determine rate of rise: A 1.0 mEq/L increase in one day indicates an acute process requiring prompt intervention

2. Immediate Stabilization (Cardiac Membrane Protection)

• Administer calcium gluconate 10%: 15-30 mL IV over 2-5 minutes
  • Onset: 1-3 minutes
  • Duration: 30-60 minutes
  • Purpose: Protects the heart from arrhythmias but does not lower potassium 1

3. Shift Potassium into Cells

• Administer insulin and glucose: 10 units regular insulin IV with 50 mL of 25% dextrose
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1
• Consider additional measures:
  • Nebulized albuterol: 10-20 mg over 15 minutes (onset: 15-30 minutes, duration: 2-4 hours)
  • Sodium bicarbonate: 50 mEq IV over 5 minutes if metabolic acidosis is present (onset: 15-30 minutes, duration: 1-2 hours) 1

4. Remove Potassium from Body

• Administer furosemide: 40-80 mg IV to enhance potassium excretion 1
• Consider potassium binder:
  • Sodium zirconium cyclosilicate (Lokelma): 10g three times daily for up to 48 hours for acute management
    • Faster onset (1 hour) compared to other binders 1, 2
  • Patiromer (Veltassa): 8.4g once daily (onset: 7 hours)
  • Note: Sodium polystyrene sulfonate should be avoided for chronic use due to GI side effects 1

5. Identify and Address Underlying Cause

• Review medications that can cause hyperkalemia:
  • ACE inhibitors/ARBs
  • NSAIDs
  • Potassium-sparing diuretics
  • Calcineurin inhibitors 1, 3
• Consider dose reduction rather than discontinuation of essential medications like ACE inhibitors/ARBs 1
• Check for volume depletion, as excessive diuresis can paradoxically worsen hyperkalemia 1

Special Considerations

Risk Factors to Assess

• Chronic kidney disease (hyperkalemia occurs in up to 73% of advanced CKD patients) 1, 4
• Heart failure (occurs in up to 40% of patients) 1
• Diabetes mellitus (especially with hyporeninemic hypoaldosteronism) 1, 5
• Medications affecting potassium homeostasis 3

Monitoring and Follow-up

• Repeat serum potassium measurements to assess response to treatment
• Monitor ECG for resolution of any abnormalities
• For patients requiring maintenance therapy, transition to once-daily dosing of potassium binder (5-10g) 1, 2

Dietary Modifications

• Limit potassium intake to <40 mg/kg/day
• Educate patient to avoid high-potassium foods:
  • Processed foods
  • Bananas, oranges
  • Potatoes, tomatoes
  • Legumes, yogurt, chocolate 1

Pitfalls and Caveats

• Do not rely solely on ECG changes to guide treatment decisions, as correlation between potassium levels and ECG findings is variable
• Ensure glucose is administered with insulin to prevent hypoglycemia
• Remember that calcium only stabilizes cardiac membranes but does not lower potassium levels
• In patients with renal failure, dialysis may be the most effective method for removing potassium 1
• When using sodium zirconium cyclosilicate, be aware it contains sodium (400mg per 5g), which may be relevant in patients with heart failure or hypertension 1, 2

Clinical trials have demonstrated that sodium zirconium cyclosilicate effectively lowers serum potassium, with a mean reduction of -0.7 mEq/L at 48 hours when administered at 10g three times daily 2.