What is the approach to treating a patient with hyperkalemia?

Approach to Hyperkalemia Management

Immediate Assessment and Classification

Verify true hyperkalemia by excluding pseudohyperkalemia from hemolysis, repeated fist clenching, or poor phlebotomy technique before initiating treatment. 1, 2

• Classify severity: Mild (5.0-5.9 mEq/L), Moderate (6.0-6.4 mEq/L), Severe (≥6.5 mEq/L) 1, 2
• Obtain ECG immediately to assess for peaked T waves, flattened P waves, prolonged PR interval, or widened QRS—these findings mandate urgent treatment regardless of potassium level 1, 2
• Do not rely solely on ECG findings as they are highly variable and less sensitive than laboratory tests 1

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Acute Management Algorithm

SEVERE Hyperkalemia (K+ ≥6.5 mEq/L OR Any ECG Changes)

Step 1: Cardiac Membrane Stabilization (Does NOT lower potassium)

• Administer IV calcium gluconate (10%): 15-30 mL over 2-5 minutes 1, 2
  • Alternative: Calcium chloride (10%): 5-10 mL over 2-5 minutes 1
  • Onset: 1-3 minutes; Duration: 30-60 minutes only 1
  • Repeat dose if no ECG improvement within 5-10 minutes 1
  • Continuous cardiac monitoring is mandatory during and after administration 1
  • Never delay calcium if ECG changes are present—do not wait for repeat labs 1

Step 2: Shift Potassium Intracellularly (Temporizing—does NOT remove potassium)

• Insulin 10 units regular IV + 50 mL of 50% dextrose (25g glucose) 1, 2

  • Onset: 15-30 minutes; Duration: 4-6 hours 1
  • Never give insulin without glucose—hypoglycemia can be life-threatening 1
  • Can repeat every 4-6 hours as needed with careful glucose monitoring 1
  • Verify potassium is not below 3.3 mEq/L before administering insulin 1

• Nebulized albuterol 20 mg in 4 mL 1, 2

  • Onset: 15-30 minutes; Duration: 2-4 hours 1
  • Use as adjunctive therapy with insulin 1

• Sodium bicarbonate 50 mEq IV over 5 minutes ONLY if metabolic acidosis present (pH <7.35, bicarbonate <22 mEq/L) 1, 2

  • Onset: 30-60 minutes 1
  • Do not use without metabolic acidosis—it is ineffective and wastes time 1

Step 3: Remove Potassium from Body (Definitive Treatment)

• Loop diuretics: Furosemide 40-80 mg IV if adequate kidney function present 1, 2

  • Increases renal potassium excretion 1

• Hemodialysis is the most effective and reliable method for severe hyperkalemia, especially in: 1, 2

  • Renal failure or oliguria
  • Cases unresponsive to medical management
  • End-stage renal disease

Step 4: Medication Review

• Temporarily discontinue or reduce: 1, 2
  • RAAS inhibitors (ACE inhibitors, ARBs, mineralocorticoid antagonists) if K+ >6.5 mEq/L
  • NSAIDs
  • Potassium-sparing diuretics (spironolactone, amiloride, triamterene)
  • Trimethoprim
  • Heparin
  • Beta-blockers
  • Potassium supplements and salt substitutes

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MODERATE Hyperkalemia (K+ 6.0-6.4 mEq/L, No ECG Changes)

• Insulin 10 units regular IV + 25g dextrose 1
• Nebulized albuterol 20 mg 1
• Loop diuretics if adequate renal function 1
• Initiate potassium binder therapy (see chronic management below) 1
• Review and eliminate contributing medications 1

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MILD Hyperkalemia (K+ 5.0-5.9 mEq/L, No ECG Changes)

• Do NOT initiate acute interventions (calcium, insulin, albuterol) 1
• Review and eliminate contributing medications 1
• Consider loop diuretics if adequate renal function 1
• Initiate potassium binder if on RAAS inhibitors or recurrent hyperkalemia 1

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Chronic Hyperkalemia Management

Potassium Binder Therapy (Preferred Agents)

For K+ 5.0-6.5 mEq/L on RAAS inhibitors:

• Maintain RAAS inhibitor therapy—do NOT discontinue permanently as these provide mortality benefit 1, 2

First-Line: Sodium Zirconium Cyclosilicate (SZC/Lokelma)

• Dosing: 10g three times daily for 48 hours, then 5-15g once daily for maintenance 1
• Onset: ~1 hour (suitable for urgent outpatient scenarios) 1
• Monitor for edema due to sodium content 1

Second-Line: Patiromer (Veltassa)

• Dosing: 8.4g once daily with food, titrate up to 25.2g daily based on response 1
• Onset: ~7 hours 1
• Separate from other oral medications by at least 3 hours 1
• Monitor magnesium levels—causes hypomagnesemia 1

Avoid: Sodium Polystyrene Sulfonate (Kayexalate)

• Delayed onset, limited efficacy, risk of bowel necrosis 1, 3
• Should not be used as emergency treatment due to delayed onset of action 3

Diuretic Optimization

• Loop or thiazide diuretics (furosemide 40-80 mg daily) to promote urinary potassium excretion 1, 2
• Titrate to maintain euvolemia, not primarily for potassium management 1

RAAS Inhibitor Management

For K+ 5.0-6.5 mEq/L:

• Maintain current RAAS inhibitor dose + initiate potassium binder 1, 2

For K+ >6.5 mEq/L:

• Temporarily reduce or hold RAAS inhibitor 1, 2
• Initiate potassium binder 1
• Restart RAAS inhibitor at lower dose once K+ <5.0 mEq/L 1

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Monitoring Protocol

• Check potassium within 1 week of starting or escalating RAAS inhibitors 1, 2
• Reassess 7-10 days after initiating potassium binder therapy 1, 2
• High-risk patients require more frequent monitoring: 1, 2
  • Chronic kidney disease
  • Heart failure
  • Diabetes mellitus
  • History of hyperkalemia
• Monitor every 2-4 hours after initial acute treatment 1

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Sample Doctor's Orders

For Severe Hyperkalemia (K+ ≥6.5 mEq/L or ECG Changes):

1. Continuous cardiac monitoring
2. Calcium gluconate 10% solution: 30 mL IV over 2-5 minutes NOW
   - Repeat in 5-10 minutes if no ECG improvement
3. Regular insulin 10 units IV push + D50W 50 mL IV push NOW
4. Albuterol 20 mg nebulized in 4 mL NOW
5. Furosemide 80 mg IV NOW (if eGFR >30)
6. Recheck potassium in 2 hours
7. Hold ACE inhibitor/ARB/MRA
8. Nephrology consult for possible hemodialysis
9. Initiate sodium zirconium cyclosilicate 10g PO TID for 48 hours

For Moderate Hyperkalemia (K+ 6.0-6.4 mEq/L, No ECG Changes):

1. Regular insulin 10 units IV push + D50W 50 mL IV push NOW
2. Albuterol 20 mg nebulized in 4 mL NOW
3. Furosemide 40 mg IV NOW (if eGFR >30)
4. Recheck potassium in 4 hours
5. Review medication list—hold NSAIDs, potassium supplements
6. Initiate patiromer 8.4g PO daily with food
7. Recheck potassium in 7 days

For Mild Hyperkalemia (K+ 5.0-5.9 mEq/L on RAAS Inhibitor):

1. Continue current RAAS inhibitor dose
2. Initiate patiromer 8.4g PO daily with food
   - Separate from other medications by 3 hours
3. Eliminate potassium supplements and salt substitutes
4. Review medication list—discontinue NSAIDs if possible
5. Recheck potassium in 7 days
6. Monitor magnesium levels monthly

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Critical Pitfalls to Avoid

• Never delay calcium administration if ECG changes are present—do not wait for repeat potassium levels 1
• Never give insulin without glucose 1
• Never use sodium bicarbonate without metabolic acidosis 1
• Remember calcium, insulin, and beta-agonists do NOT remove potassium—they only temporize 1, 2
• Do not permanently discontinue RAAS inhibitors in cardiovascular disease, heart failure, or proteinuric CKD—use potassium binders instead 1
• Do not use sodium polystyrene sulfonate for acute management due to delayed onset and bowel necrosis risk 1, 3