How to manage hyperkalemia in a patient on Lasix (furosemide) and eplerenone (an aldosterone antagonist) after a recent quadruple bypass surgery?

Management of Hyperkalemia in a Post-Bypass Patient on Eplerenone and Furosemide

For a patient with potassium of 6.0 mEq/L on eplerenone and furosemide, eplerenone should be temporarily discontinued, not just held for 48 hours, until potassium levels normalize below 5.5 mEq/L. 1, 2

Immediate Management Steps

• Discontinue eplerenone immediately as potassium >6.0 mEq/L is considered severe hyperkalemia and requires prompt intervention 1, 3
• Obtain an ECG to assess for hyperkalemia-related changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) 1
• Consider hospital admission for monitoring and treatment if ECG changes are present or patient is symptomatic 1
• Recheck potassium and renal function within 24-48 hours 3
• Assess for other contributing factors to hyperkalemia:
  • Medication review (NSAIDs, ACE inhibitors, ARBs) 3
  • Dietary potassium intake 3
  • Renal function 3
  • Volume status 3

Rationale for Discontinuation vs. Holding

• Potassium >6.0 mEq/L represents severe hyperkalemia with increased risk of cardiac arrhythmias and sudden death 1
• FDA labeling for eplerenone states that the drug is contraindicated in patients with serum potassium >5.5 mEq/L 2
• Guidelines recommend discontinuation of aldosterone antagonists when potassium exceeds 5.5 mEq/L 3
• Simply holding the medication for 48 hours may be insufficient as hyperkalemia can persist, especially in patients with renal impairment 3

Monitoring and Follow-up

• Recheck potassium and renal function within 24-48 hours after discontinuing eplerenone 3
• Continue monitoring potassium levels at least weekly until stabilized below 5.5 mEq/L 3
• Consider increasing furosemide dose temporarily to enhance potassium excretion if renal function permits 4
• Counsel patient to avoid high-potassium foods and supplements 3

Considerations for Restarting Eplerenone

• Eplerenone may be restarted only after potassium has normalized to <5.0 mEq/L 2
• When restarting, use a lower dose (12.5 mg daily or every other day) 3
• Monitor potassium within 3-7 days after restarting 3
• Consider whether the benefit of eplerenone outweighs the risk of recurrent hyperkalemia in this patient 5

Common Pitfalls to Avoid

• Failing to discontinue eplerenone with severe hyperkalemia (>6.0 mEq/L) 1, 2
• Inadequate follow-up monitoring after medication changes 3
• Restarting eplerenone too soon or at too high a dose 3
• Not considering other contributing factors to hyperkalemia 3
• Continuing potassium supplements if previously prescribed 3
• Not instructing patients to temporarily stop eplerenone during episodes of dehydration, diarrhea, or when loop diuretic therapy is interrupted 3