What is the management plan for a patient with hyperkalemia?

Management of Hyperkalemia with Potassium of 6.4 mEq/L

For a patient with severe hyperkalemia (potassium 6.4 mEq/L), immediate treatment with IV calcium, insulin/glucose, and nebulized beta-agonists should be initiated, followed by measures to eliminate excess potassium from the body.

Immediate Management (First Hours)

Step 1: Cardiac Membrane Stabilization

• Administer IV calcium gluconate: 10 mL of 10% solution IV over 2-3 minutes 1
  • Acts within 1-3 minutes to protect cardiac tissue
  • May repeat dose if no effect observed within 5-10 minutes
  • Monitor ECG continuously during administration

Step 2: Shift Potassium Intracellularly (30-60 minutes)

• Administer IV insulin with glucose: 10 units regular insulin with 50 mL of 50% dextrose 1
  • Onset within 30 minutes, lasts 4-6 hours
  • Monitor blood glucose levels to prevent hypoglycemia
• Nebulized beta-agonist: 20 mg salbutamol (albuterol) in 4 mL nebulizer solution 1
  • Can be used concurrently with insulin/glucose
  • Particularly useful in patients with diabetes to minimize glucose administration

Step 3: Eliminate Excess Potassium

• Diuretics: IV furosemide if patient has adequate kidney function and is volume overloaded 1
• Sodium bicarbonate: Consider if patient has concurrent metabolic acidosis 1
• Hemodialysis: Consider urgent dialysis if:
  • Patient has severe symptoms
  • ECG changes persist
  • Patient has end-stage renal disease or oliguric kidney failure
  • Potassium remains dangerously elevated despite above measures 1

Short-term Management (24-48 hours)

Step 1: Identify and Address Underlying Causes

• Review medications that may cause hyperkalemia:
  • Renin-angiotensin-aldosterone system inhibitors (ACEIs, ARBs, MRAs)
  • Potassium-sparing diuretics
  • NSAIDs
  • Beta-blockers
  • Trimethoprim-sulfamethoxazole 1
• Check for other causes:
  • Kidney dysfunction
  • Metabolic acidosis
  • Tissue breakdown (rhabdomyolysis, tumor lysis)
  • Adrenal insufficiency

Step 2: Initiate Potassium Binders

• Sodium zirconium cyclosilicate (Lokelma):
  • 10g three times daily for 24-48 hours 2
  • Monitor for edema as each 5g dose contains approximately 400mg sodium
  • Avoid in patients with severe constipation or bowel obstruction 2
• Patiromer or Sodium polystyrene sulfonate are alternatives

Long-term Management

Step 1: Optimize Medication Regimen

• If patient requires RAAS inhibitors for cardiac or renal protection:
  • Consider lower doses rather than complete discontinuation 1
  • Monitor potassium levels within one week of any dose adjustment 1

Step 2: Maintenance Therapy

• Consider maintenance dose of newer potassium binders to allow continuation of beneficial RAAS inhibitors 1
• Regular potassium monitoring:
  • Initially weekly until stable
  • Then monthly or quarterly based on risk factors

Step 3: Dietary Considerations

• Focus on reducing non-plant sources of potassium rather than strict overall potassium restriction 3
• Avoid salt substitutes and potassium supplements 1

Special Considerations

• ECG monitoring: Peaked T waves, prolonged PR interval, widened QRS, and loss of P waves indicate increasing severity 1
• Medication spacing: If using potassium binders, administer other oral medications at least 2 hours before or after to prevent altered absorption 2
• Rebound hyperkalemia: Monitor for rebound increases in potassium levels after acute treatment, particularly in patients with ongoing kidney dysfunction 1

Common Pitfalls to Avoid

1. Delaying treatment in severe hyperkalemia (>6.0 mEq/L) while awaiting confirmation
2. Failing to repeat potassium measurement after initial treatment
3. Overlooking pseudohyperkalemia from hemolysis or improper sample collection
4. Discontinuing beneficial RAAS inhibitors when potassium binders could allow their continued use
5. Administering calcium in patients on digoxin without extreme caution (increased risk of digoxin toxicity)