What is the treatment for hyperkalemia?

Treatment of Hyperkalemia

The treatment of hyperkalemia requires a stepwise approach starting with cardiac membrane stabilization using intravenous calcium, followed by shifting potassium into cells with insulin and glucose, and ultimately eliminating potassium from the body through various methods depending on severity and renal function. 1, 2

Classification of Hyperkalemia

• Mild: 5.0-5.9 mEq/L 1, 2
• Moderate: 6.0-6.4 mEq/L 1, 2
• Severe: ≥6.5 mEq/L (life-threatening) 1, 2
• ECG changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) indicate urgent treatment regardless of potassium level 1, 2

Step 1: Cardiac Membrane Stabilization (Immediate Effect)

• Administer intravenous calcium to protect the heart from arrhythmias 1, 3
  • Calcium chloride (10%): 5-10 mL (500-1000 mg) IV over 2-5 minutes (preferred option) 1
  • OR Calcium gluconate (10%): 15-30 mL IV over 2-5 minutes 1
• Effects begin within minutes but are temporary (30-60 minutes) 1
• Note: Calcium does not lower serum potassium but protects against arrhythmias 1
• Caution: Avoid in patients taking digoxin as it may potentiate digoxin toxicity 3

Step 2: Shift Potassium into Cells (Effect within 15-30 minutes)

• Insulin with glucose: 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 1, 2
  • Effect lasts 4-6 hours 1
  • Monitor glucose levels to prevent hypoglycemia 3
  • Can be repeated every 4-6 hours as needed 2
• Nebulized beta-2 agonists: 10-20 mg albuterol over 15 minutes 1
  • Can be used alone or to augment insulin effect 4
• Sodium bicarbonate: 50 mEq IV over 5 minutes 1
  • Most effective in patients with concurrent metabolic acidosis 1, 2

Step 3: Eliminate Potassium from Body (Longer-term Effect)

• Loop diuretics: furosemide 40-80 mg IV 1, 2
  • Effective only in patients with adequate renal function 1
• Normal saline (0.9% NaCl): Provides volume expansion and improves renal perfusion 3
  • Avoid potassium-containing fluids like Lactated Ringer's 3
• Cation exchange resins or newer potassium binders 1, 2
  • Sodium polystyrene sulfonate (Kayexalate): 15-50 g orally or rectally 1
  • Not for emergency treatment of life-threatening hyperkalemia due to delayed onset of action 5
  • Newer agents (patiromer, sodium zirconium cyclosilicate) are safer alternatives 1
• Hemodialysis: Most effective method for severe hyperkalemia, especially in renal failure 1, 2

Monitoring During Treatment

• Check serum potassium levels at 1-2 hour intervals during acute treatment 3
• Monitor ECG changes to indicate improvement or worsening 3
• Watch for rebound hyperkalemia 2-4 hours after treatment 1, 3
• Monitor blood glucose frequently when using insulin 3

Important Clinical Considerations

• Temporary measures (insulin/glucose, albuterol) provide only transient effects (1-4 hours) 1
• Rebound hyperkalemia can occur after 2 hours 1
• Review and adjust medications that may contribute to hyperkalemia (ACE inhibitors, ARBs, MRAs, NSAIDs, beta-blockers) 1, 2
• For chronic hyperkalemia management in patients on RAAS inhibitors:
  • For levels >5.0 mEq/L: Initiate potassium-lowering agent and maintain RAAS inhibitor therapy 1
  • For severe hyperkalemia (>6.5 mEq/L): Consider discontinuing or reducing RAAS inhibitor dose 1

Special Populations

• Pediatric patients:
  • Calcium chloride dosing: 20 mg/kg (0.2 mL/kg for 10% CaCl₂) 1
  • Insulin: 0.1 unit/kg with 400 mg/kg glucose 3
• Patients with malignant hyperthermia: Use calcium only in extreme cases 2

Remember that hyperkalemia treatment must be tailored to the severity of the condition, with immediate measures for life-threatening cases and more gradual approaches for chronic management 6, 7.