What is the treatment for acute hyperkalemia?

Treatment of Acute Hyperkalemia

The treatment of acute hyperkalemia requires immediate intervention with calcium gluconate to stabilize cardiac membranes, followed by insulin with glucose to shift potassium intracellularly, and additional measures based on severity and clinical presentation. 1

Initial Assessment and Severity Classification

Hyperkalemia is classified into three categories:

• Mild (5.0-5.5 mmol/L)
• Moderate (5.6-6.5 mmol/L)
• Severe (>6.5 mmol/L) 1

ECG changes correlate with severity:

• 5.5-6.5 mmol/L: Peaked/tented T waves
• 6.5-7.5 mmol/L: Prolonged PR interval, flattened P waves
• 7.0-8.0 mmol/L: Widened QRS, deep S waves

• 10 mmol/L: Sinusoidal pattern, VF, asystole, or PEA 1

Emergency Treatment Algorithm

Step 1: Cardiac Membrane Stabilization

• Administer IV calcium gluconate 10% solution (15-30 mL)
• Onset: 1-3 minutes
• Duration: 30-60 minutes 1

Step 2: Intracellular Potassium Shift

• Administer 10 units regular insulin IV with 50 mL of 25% dextrose
• Onset: 15-30 minutes
• Duration: 1-2 hours 1

Step 3: Additional Measures (Based on Clinical Scenario)

• Inhaled beta-agonists: 10-20 mg nebulized over 15 minutes
  • Onset: 15-30 minutes
  • Duration: 2-4 hours 1
• Sodium bicarbonate: 50 mEq IV over 5 minutes (if metabolic acidosis present)
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1

Step 4: Potassium Elimination

• Hemodialysis: Most rapid and effective method for eliminating potassium, especially in severe cases with renal failure or when other measures fail 1, 2
• Loop diuretics: Promote renal excretion of potassium (if renal function adequate) 1
• Potassium binders:
  • Sodium zirconium cyclosilicate (SZC/Lokelma): Onset 1 hour
  • Patiromer: Onset 7 hours
  • Sodium polystyrene sulfonate: Variable onset (several hours) 1, 3

Important Clinical Considerations

Potassium Binder Selection

Newer potassium binders are preferred over sodium polystyrene sulfonate:

• Patiromer and SZC: More effective with fewer adverse effects 3
• Sodium polystyrene sulfonate: Associated with serious gastrointestinal adverse effects 3
• Note: Sodium polystyrene sulfonate should not be used as emergency treatment for life-threatening hyperkalemia due to its delayed onset of action 4

Comparative Effectiveness

• Salbutamol (beta-agonist) and insulin-dextrose have comparable effectiveness in reducing serum potassium 5
• Both are more effective than sodium bicarbonate 5
• Insulin-dextrose is more effective than aminophylline 5

Common Pitfalls to Avoid

1. Delayed treatment: Severe hyperkalemia is a medical emergency requiring immediate intervention 1, 6
2. Overlooking drug interactions: Potassium-sparing diuretics, NSAIDs, and potassium supplements can worsen hyperkalemia 1
3. Inadequate monitoring: Potassium levels should be checked frequently during acute treatment 1
4. Relying solely on potassium binders for acute management: They have delayed onset and should not be used as standalone emergency treatment 4, 3
5. Discontinuing RAAS inhibitors without attempting dose reduction: Complete discontinuation is associated with poorer clinical outcomes 1, 7

Post-Acute Management

• Monitor potassium and renal function within 1-2 weeks of initiating or changing treatment 1
• Continue monitoring potassium levels at least monthly for the first 3 months, then every 3 months 1
• Counsel patients on dietary modifications:
  • Limit potassium intake to <40 mg/kg/day
  • Avoid high-potassium foods
  • Avoid potassium-containing salt substitutes
  • Pre-soak root vegetables to reduce potassium content by 50-75% 1
• Maintain adequate hydration 1
• Avoid NSAIDs 1, 3