How do I manage hyperkalemia?

Management of Hyperkalemia

The management of hyperkalemia requires prompt assessment of severity and implementation of appropriate interventions based on potassium level, ECG changes, and symptoms, with immediate stabilization measures for severe cases (K+ >6.5 mmol/L) or those with ECG changes. 1

Assessment and Stratification

Severity Assessment

• Mild: 5.0-5.5 mmol/L
• Moderate: 5.5-6.5 mmol/L
• Severe: >6.5 mmol/L

ECG Changes by Potassium Level

• 5.5-6.5 mmol/L: Peaked/tented T waves (early sign)
• 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

Urgent Treatment Algorithm

Step 1: Cardiac Membrane Stabilization (for ECG changes or K+ >6.5)

• Calcium gluconate: 10% solution, 15-30 mL IV
  • Onset: 1-3 minutes
  • Duration: 30-60 minutes
  • Note: Protects the heart but does not lower potassium levels 1, 2

Step 2: Intracellular Shift of Potassium

• Insulin with glucose: 10 units regular insulin IV with 50 mL of 25% dextrose
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1
• 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 (especially useful in metabolic acidosis)
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1

Step 3: Potassium Removal

• Loop diuretics (if adequate renal function)
• Potassium binders:
  • Sodium zirconium cyclosilicate (Lokelma): 5-10g once daily (onset: 1 hour)
  • Patiromer (Veltassa): 8.4g once daily (onset: 7 hours)
  • Sodium polystyrene sulfonate: 15-30g (use cautiously due to GI side effects) 1, 2
• Dialysis: Consider for severe hyperkalemia with renal failure, ongoing potassium release, or when other measures fail 2

Non-Urgent Management

Medication Review and Adjustment

• Evaluate and modify medications that contribute to hyperkalemia:
  • ACE inhibitors/ARBs/direct renin inhibitors
  • Potassium-sparing diuretics
  • NSAIDs
  • Trimethoprim
  • Calcineurin inhibitors
  • Beta-blockers
  • Heparin 1, 3

Dietary Modifications

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

Ongoing Monitoring

• Monitor serum potassium based on risk factors:
  • More frequent monitoring for CKD, diabetes, heart failure, history of hyperkalemia
  • Target potassium levels ≤5 mmol/L, especially in heart failure patients 1

Special Considerations

Chronic Kidney Disease

• Higher risk of hyperkalemia (up to 73% in advanced CKD)
• Consider nephrology consultation for:
  • CKD stage 4 (eGFR <30 mL/min/1.73 m²)
  • Persistent hyperkalemia despite standard measures
• Begin dialysis education when eGFR <15 mL/min/1.73 m² 1, 4

Heart Failure

• Hyperkalemia occurs in up to 40% of patients
• Consider newer potassium binders to facilitate optimal RAAS inhibitor therapy
• Balance between hyperkalemia risk and benefits of RAAS inhibitors 1

Common Pitfalls to Avoid

1. Failing to check ECG: Always obtain an ECG in hyperkalemia, as cardiac conduction abnormalities may occur even with modest elevations
2. Overlooking pseudohyperkalemia: Hemolysis, thrombocytosis, or improper blood collection can falsely elevate potassium
3. Calcium administration in digoxin toxicity: Use calcium with caution in patients on digoxin
4. Inadequate glucose with insulin: Monitor for hypoglycemia when administering insulin
5. Overreliance on sodium polystyrene sulfonate: Associated with serious GI adverse effects; newer binders are safer for ongoing management 2

By following this structured approach to hyperkalemia management, you can effectively address this potentially life-threatening condition while minimizing complications.