How do you manage hyperkalemia?

Management of Hyperkalemia

The management of hyperkalemia requires a stepwise approach based on severity, with immediate cardiac stabilization for severe cases, followed by potassium-lowering therapies and addressing underlying causes. 1

Classification and Initial Assessment

Hyperkalemia is classified as:

• Mild: >5.0 to <5.5 mEq/L
• Moderate: 5.5 to 6.0 mEq/L
• Severe: >6.0 mEq/L 1

Immediate Assessment

1. Obtain ECG to evaluate for cardiac effects
2. Check serum potassium, creatinine, and other electrolytes
3. Assess for ECG changes that correlate with potassium levels:
   • 5.5-6.5 mmol/L: Peaked/tented T waves
   • 6.5-7.5 mmol/L: Prolonged PR interval, flattened P waves
   • 7.0-8.0 mmol/L: Widened QRS, deep S waves

   • 10 mmol/L: Sinusoidal pattern, VF, asystole, or PEA 1

Treatment Algorithm

1. Severe Hyperkalemia (>6.0 mEq/L) or ECG Changes

• Cardiac Membrane Stabilization

  • Calcium gluconate: 10% solution, 15-30 mL IV (onset 1-3 minutes, duration 30-60 minutes) 1

• Intracellular Potassium Shift

  • Insulin with glucose: 10 units regular insulin IV with 50 mL of 25% dextrose (onset 15-30 minutes, duration 1-2 hours)
  • Inhaled beta-agonists: 10-20 mg nebulized over 15 minutes (onset 15-30 minutes, duration 2-4 hours) 1
  • For severe acidosis (pH <7.1, bicarbonate <10 mEq/L): Consider sodium bicarbonate 50 mEq IV over 5 minutes 1

• Potassium Removal

  • Hemodialysis for refractory cases or severe renal impairment 2
  • Potassium binders (see below)

2. Moderate Hyperkalemia (5.5-6.0 mEq/L)

• Insulin with glucose and consider inhaled beta-agonists as adjunctive therapy
• Review and adjust medications that may contribute to hyperkalemia
• Consider potassium binders 1

3. Mild Hyperkalemia (5.0-5.5 mEq/L) with Normal ECG

• Review and adjust medications that may contribute to hyperkalemia
• Consider potassium binders if persistent 1

Potassium Binders

Options:

1. Sodium Polystyrene Sulfonate (SPS)

   • Dosage: 15-60g daily, divided into 15g doses 1-4 times daily 3
   • Administration: Suspend each dose in 3-4 mL of liquid per gram of resin 3
   • Timing: At least 3 hours before or 3 hours after other oral medications 3
   • Caution: Associated with serious gastrointestinal adverse effects 2

2. Patiromer

   • Onset: 7 hours
   • Advantage: No sodium content
   • Site of action: Colon 1

3. Sodium Zirconium Cyclosilicate (SZC)

   • Onset: 1 hour
   • Site of action: Small and large intestines
   • Contains 400mg sodium per 5g dose 1

Monitoring and Prevention

• Check serum potassium and renal function within 2-4 days of initiating or adjusting RAAS inhibitor therapy
• Regularly monitor ECG to detect hyperkalemia-related changes 1
• Limit potassium intake to <40 mg/kg/day
• Educate patients on high-potassium foods to avoid (bananas, oranges, potatoes, tomato products, legumes, yogurt, chocolate) 1

Special Considerations

RAAS Inhibitor Therapy

• Do not discontinue RAAS inhibitors (ACEi/ARBs) after a single episode of hyperkalemia
• Consider dose reduction rather than complete discontinuation
• Only discontinue if:
  • Serum creatinine rises by >30% within 4 weeks of initiation
  • Uncontrolled hyperkalemia despite medical treatment
  • Symptomatic hypotension occurs 1

Rectal Administration (for patients unable to take oral medications)

• After cleansing enema, insert a soft, large size (French 28) rubber tube into rectum for about 20 cm
• Administer as a warm emulsion in 100 mL of aqueous vehicle and flush with 50-100 mL of fluid
• Retain as long as possible and follow with a non-sodium containing cleansing solution 3

Common Pitfalls to Avoid

1. Failure to obtain ECG: Always get an ECG to assess cardiac effects, even with mild hyperkalemia
2. Overlooking transcellular shifts: Consider potential causes of transcellular shifts as patients are at risk of rebound potassium disturbances 4
3. Inadequate monitoring: Potassium levels should be monitored frequently during acute treatment
4. Neglecting underlying causes: Identify and address the root cause of hyperkalemia for effective long-term management
5. Abrupt discontinuation of RAAS inhibitors: These medications provide mortality benefit; consider dose reduction rather than discontinuation 1