What is the immediate treatment for hyperkalemia?

Immediate Treatment for Hyperkalemia

The immediate treatment for hyperkalemia should begin with intravenous calcium (calcium gluconate 10%: 15-30 mL IV over 5-10 minutes) to stabilize cardiac membranes, followed by insulin with glucose (10 units regular insulin IV with 50 mL of 25% dextrose) to shift potassium intracellularly. 1

Emergency Management Algorithm

Step 1: Assess Severity and Stabilize Cardiac Membranes

• Check for ECG changes which correlate with potassium levels:

  • 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

• Administer calcium gluconate immediately:

  • Dosage: 10% solution, 15-30 mL IV (20 mg/kg or 0.2 mL/kg) over 5-10 minutes
  • Onset: 1-3 minutes
  • Duration: 30-60 minutes
  • Purpose: Protects the heart from arrhythmias but does not lower potassium levels 1
  • Do not delay administration while awaiting laboratory confirmation if hyperkalemia is suspected 1

Step 2: Shift Potassium Intracellularly

• Administer insulin with glucose:

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

• Consider nebulized beta-agonists:

  • Dosage: 10-20 mg nebulized over 15 minutes
  • Onset: 15-30 minutes
  • Duration: 2-4 hours
  • Can augment the effects of insulin and glucose 1, 3

• Consider sodium bicarbonate (especially if metabolic acidosis is present):

  • Dosage: 50 mEq IV over 5 minutes
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1
  • Particularly indicated for hyperkalemia with concurrent metabolic acidosis, ECG changes, or tricyclic antidepressant overdose 1

Step 3: Eliminate Excess Potassium

• Administer IV furosemide if renal function permits 1

• Consider potassium binders:

  • Patiromer (Veltassa): 8.4g once daily (onset: 7 hours)
  • Sodium zirconium cyclosilicate (Lokelma): 5-10g once daily (onset: 1 hour)
  • Sodium polystyrene sulfonate: 15-30g (avoid chronic use due to GI side effects) 1, 2

• Consider hemodialysis for severe cases, especially with:

  • End-stage renal disease
  • Severe renal impairment
  • Ongoing potassium release
  • Failure of conventional therapies 4, 2

Important Considerations and Pitfalls

Monitoring

• Obtain serial ECGs to monitor for progression of changes 1
• Implement continuous cardiac monitoring for moderate to severe hyperkalemia 1
• Recheck potassium levels after treatment to avoid overcorrection 1

Cautions

1. Volume status: Patients with heart failure or renal failure should be monitored for volume overload when using sodium bicarbonate 1
2. Medication review: Carefully review prescribed drugs that may be affecting potassium homeostasis 3
3. Calcium administration: Do not mix calcium with vasoactive amines or other calcium preparations 1
4. Avoid:
   • IV bolus administration of potassium for cardiac arrest in suspected hypokalemia (Class 3: Harm) 1
   • Lidocaine or phenytoin for digitalis-induced hyperkalemia and arrhythmias 1

Common Causes to Address

• Kidney failure
• Medications affecting the renin-angiotensin-aldosterone system
• Decreased delivery of sodium and water to the distal nephron 3

The most recent evidence emphasizes the importance of prompt recognition and treatment of hyperkalemia to prevent serious cardiac complications. While calcium stabilizes cardiac membranes within minutes, it does not lower potassium levels, making the subsequent steps of insulin/glucose administration crucial for shifting potassium intracellularly 1, 2. For patients with severe hyperkalemia unresponsive to conventional therapy, early consideration of hemodialysis may be life-saving 4.