How should mild hyperkalemia be managed?

Management of Mild Hyperkalemia

For mildly elevated potassium (5.0–5.5 mEq/L), focus on identifying and removing contributing medications, optimizing diuretics if renal function permits, and monitoring closely—acute interventions like calcium or insulin are not indicated unless ECG changes appear. 1

---

Initial Assessment

Rule Out Pseudohyperkalemia

• Repeat the measurement using proper phlebotomy technique (avoid prolonged tourniquet use, fist clenching, or hemolyzed samples) to exclude laboratory artifact 1, 2
• Consider arterial sampling if venous draws remain questionable 1

Obtain an ECG Immediately

• Look for peaked T waves (earliest sign, typically >5.5 mEq/L), flattened P waves, prolonged PR interval, or widened QRS complex 1, 3
• If any ECG changes are present, treat as moderate-to-severe hyperkalemia regardless of the absolute potassium value 1, 2
• Absence of ECG changes does not guarantee safety—individual variability exists, and rapid rises pose greater cardiac risk than gradual elevations 3

---

Medication Review and Adjustment

Identify and Modify Contributing Drugs

• RAAS inhibitors (ACE inhibitors, ARBs, mineralocorticoid receptor antagonists): Reduce dose by 50% or temporarily hold if potassium approaches 5.5 mEq/L; do not permanently discontinue these life-saving agents 1, 2
• NSAIDs: Discontinue unless absolutely essential, as they impair renal potassium excretion 1, 2
• Potassium-sparing diuretics (spironolactone, amiloride, triamterene): Reduce dose by 50% at potassium >5.5 mEq/L or hold temporarily 1, 2
• Other contributors: Review trimethoprim, heparin, beta-blockers, potassium supplements, and salt substitutes 1, 2

Optimize Diuretic Therapy

• If eGFR >30 mL/min and urine output is adequate, initiate or increase loop diuretics (furosemide 40–80 mg daily) to enhance urinary potassium excretion 1, 2
• Thiazide diuretics are an alternative in patients with preserved renal function 1

---

Dietary Modifications

• Restrict potassium intake to <3 g/day (approximately 50–70 mmol/day) 1, 2
• Avoid high-potassium foods: bananas, oranges, melons, potatoes, tomato products, legumes, lentils, chocolate, yogurt 1, 2
• Eliminate salt substitutes containing potassium chloride 1, 2
• Caveat: Stringent dietary restriction alone has limited impact on serum potassium and may deprive patients of cardiovascular benefits from potassium-rich diets; prioritize medication adjustments over extreme dietary limits 1

---

Consider Potassium Binders for Chronic Management

When to Initiate

• Patients on RAAS inhibitors with recurrent mild hyperkalemia (potassium persistently >5.0 mEq/L) should start a potassium binder to enable continuation of cardioprotective therapy 1, 2
• Patients with chronic kidney disease, heart failure, or diabetes at high risk for progression 1, 2

Preferred Agents

• Sodium zirconium cyclosilicate (SZC/Lokelma): 10 g three times daily for 48 hours, then 5–15 g once daily; onset ~1 hour 1, 2
• Patiromer (Veltassa): 8.4 g once daily with food, titrated up to 25.2 g daily; onset ~7 hours; separate from other oral medications by ≥3 hours 1, 2
• Avoid sodium polystyrene sulfonate (Kayexalate): Risk of bowel necrosis, colonic ischemia, and inconsistent efficacy 1, 2

---

Monitoring Protocol

• Recheck potassium within 24–48 hours after initial interventions 2
• If RAAS inhibitors are adjusted, repeat potassium within 1 week 1, 2
• After initiating a potassium binder, reassess within 7–10 days 1, 2
• Tailor ongoing monitoring frequency to comorbidities (CKD, heart failure, diabetes) and medication regimen 1, 2

---

Investigate Underlying Causes

• Acute kidney injury or worsening CKD: Check creatinine, eGFR, and urine output 1, 2
• Metabolic acidosis: Obtain venous blood gas if pH <7.35 and bicarbonate <22 mEq/L; sodium bicarbonate is only indicated when acidosis is present 1, 3
• Volume depletion: Assess hydration status and consider IV saline if hypovolemic 1
• Endocrine disorders: Evaluate for adrenal insufficiency or hypoaldosteronism if clinically suspected 2
• Tissue breakdown: Consider rhabdomyolysis, tumor lysis syndrome, or hemolysis in appropriate contexts 1, 4

---

When to Escalate Care

Immediate Hospital Referral Indicated If:

• Potassium rises to >6.0 mEq/L on repeat testing 2
• ECG changes develop (peaked T waves, widened QRS, prolonged PR interval) 1, 2
• Patient develops symptoms (muscle weakness, paresthesias, palpitations) 2
• Rapid deterioration of renal function (creatinine >2.5 mg/dL in men, >2.0 mg/dL in women) 2
• Oliguria or anuria 1

---

Common Pitfalls to Avoid

• Do not permanently discontinue RAAS inhibitors due to mild hyperkalemia; dose reduction plus potassium binders is preferred to maintain mortality and morbidity benefits in heart failure and CKD 1, 2
• Do not ignore the 5.5 mEq/L threshold for dose adjustments; waiting until potassium reaches 6.0 mEq/L increases arrhythmia risk 1, 2
• Do not delay treatment while awaiting repeat lab confirmation if clinical suspicion is high or ECG changes are present 1, 3
• Do not assume mild hyperkalemia is benign in high-risk patients (CKD, heart failure, diabetes, elderly) or when potassium is rising rapidly 1, 3
• Do not overlook pseudohyperkalemia from poor phlebotomy technique or delayed sample processing 1, 2