What is the treatment for hyperkalemia?

Treatment of Hyperkalemia

The treatment of hyperkalemia requires a stepwise approach based on severity, with immediate cardiac membrane stabilization using intravenous calcium, followed by shifting potassium into cells with insulin/glucose and beta-agonists, and finally eliminating potassium from the body through diuretics, potassium binders, or hemodialysis. 1, 2

Assessment and Classification

• Hyperkalemia is classified as mild (5.0-5.9 mEq/L), moderate (6.0-6.4 mEq/L), or severe (≥6.5 mEq/L) 1, 2
• ECG changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) indicate urgent treatment regardless of potassium level 1, 2
• Symptoms may be nonspecific, and ECG findings can be variable and less sensitive than laboratory tests 2

Step 1: Cardiac Membrane Stabilization

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

Step 2: Shift Potassium into Cells

• Administer insulin with glucose: 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 1, 2, 3
• Onset within 15-30 minutes, effect lasts 4-6 hours 1, 3
• Nebulized albuterol: 10-20 mg over 15 minutes 1, 4
• Can combine insulin/glucose with albuterol for additive effect 5
• Sodium bicarbonate (50 mEq IV over 5 minutes) most effective in patients with concurrent metabolic acidosis 1

Step 3: Eliminate Potassium from Body

• Loop diuretics (furosemide: 40-80 mg IV) for patients with adequate renal function 1, 2
• Potassium binders:
  • Newer agents (patiromer and sodium zirconium cyclosilicate) are safer alternatives for both acute and chronic management 2, 4
  • Sodium polystyrene sulfonate (Kayexalate): 15-50 g orally or rectally with sorbitol 1
    • Not for emergency treatment of life-threatening hyperkalemia due to delayed onset of action 6
    • Associated with serious gastrointestinal adverse effects 4
• Hemodialysis is the most effective method for severe hyperkalemia, especially in patients with renal failure 1, 2, 4

IV Fluid Management

• Normal saline (0.9% NaCl) is the first-line IV fluid for acute hyperkalemia 3
• Avoid potassium-containing fluids like Lactated Ringer's 3
• Normal saline alone is insufficient and must be combined with other potassium-lowering strategies 3

Monitoring During Treatment

• Check serum potassium levels at 1-2 hour intervals during acute treatment 3
• Monitor blood glucose frequently to prevent hypoglycemia 3
• Watch for rebound hyperkalemia 2-4 hours after treatment 1, 3

Long-term Management

• Review and adjust medications that may contribute to hyperkalemia (ACE inhibitors, ARBs, MRAs, NSAIDs, beta-blockers) 1, 2, 4
• Consider loop or thiazide diuretics for chronic management in patients with adequate kidney function 2
• Newer potassium binders can be used for chronic hyperkalemia management 2, 7
• Patients with cardiovascular disease on RAAS inhibitors require careful monitoring of potassium levels 2
• High-risk patients (chronic kidney disease, heart failure, diabetes) need more frequent monitoring 2, 7

Common Pitfalls and Caveats

• Temporary measures (insulin/glucose, albuterol) provide only transient effects; definitive treatment of the underlying cause is necessary 3, 5
• Absent or atypical ECG changes do not exclude the necessity for immediate intervention 5
• Rebound hyperkalemia can occur after 2 hours of treatment with temporary measures 1
• Sodium polystyrene sulfonate should not be used for emergency treatment 6