What is the proper treatment for hyperkalemia in the emergency department?

Emergency Management of Hyperkalemia

The proper treatment of hyperkalemia in the emergency department requires immediate administration of IV calcium gluconate for cardiac stabilization in patients with ECG changes, followed by insulin with glucose and beta-agonists to shift potassium intracellularly, and measures to eliminate potassium from the body. 1

Initial Assessment and Stratification

Severity Assessment

• Mild: 5.0-5.5 mmol/L
• Moderate: 5.6-6.5 mmol/L
• Severe: >6.5 mmol/L

ECG Changes by Potassium Level

Potassium Level	ECG Changes
5.5-6.5 mmol/L	Peaked/tented T waves (early sign)
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

Treatment Algorithm

Step 1: Cardiac Membrane Stabilization (for ECG changes or K+ >6.5 mmol/L)

• Calcium gluconate: 10% solution, 15-30 mL IV
  • Onset: 1-3 minutes
  • Duration: 30-60 minutes
  • Does not lower serum potassium but protects against arrhythmias 1, 2

Step 2: Intracellular Shift of Potassium

• Insulin with glucose:

  • 10 units regular insulin IV with 50 mL of 25% dextrose
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1

• Inhaled beta-agonists:

  • 10-20 mg nebulized over 15 minutes
  • Onset: 15-30 minutes
  • Duration: 2-4 hours 1

• Sodium bicarbonate (especially useful in acidotic patients):

  • 50 mEq IV over 5 minutes
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1

Step 3: Elimination of Potassium from Body

• Loop diuretics (if adequate renal function):

  • 40-80 mg IV furosemide
  • Onset: 30-60 minutes
  • Duration: 2-4 hours 1

• Potassium binders:

  • For acute management in ED:
    • Sodium Zirconium Cyclosilicate (SZC): Faster onset, acts in small and large intestines
    • Patiromer: Acts in colon, slower onset
    • Sodium Polystyrene Sulfonate (SPS): Less selective, higher risk of adverse effects 3, 4

• Hemodialysis:

  • Most effective method for potassium removal
  • Indicated for:
    • Severe hyperkalemia (>6.5 mmol/L) refractory to medical therapy
    • Severe renal failure
    • Life-threatening ECG changes despite initial treatment 1, 2

Special Considerations

Medication Review

• Identify and hold medications that can worsen hyperkalemia:
  • Renin-angiotensin-aldosterone system inhibitors (RAASi)
  • Mineralocorticoid receptor antagonists (MRAs)
  • Potassium-sparing diuretics
  • NSAIDs
  • Trimethoprim
  • Beta-blockers 1

Monitoring

• Continuous cardiac monitoring during treatment
• Serial potassium measurements:
  • First check: 1-2 hours after initial treatment
  • Subsequent checks: Every 4-6 hours until stable 1
• Monitor for hypoglycemia if insulin is administered
• Watch for rebound hyperkalemia as temporary measures wear off

Pitfalls to Avoid

1. Delaying treatment in patients with ECG changes - cardiac membrane stabilization should be immediate
2. Administering calcium through the same line as bicarbonate - can precipitate
3. Using potassium-containing fluids (Lactated Ringer's or Hartmann's solution) 1
4. Relying solely on shifting agents without addressing total body potassium removal
5. Overlooking the underlying cause of hyperkalemia, which is essential for preventing recurrence

Post-Emergency Management

• Investigate and treat underlying causes:

  • Renal failure
  • Metabolic acidosis
  • Medication effects
  • Tissue breakdown (rhabdomyolysis, tumor lysis)
  • Adrenal insufficiency 1, 5

• For chronic hyperkalemia management:

  • Consider newer potassium binders (patiromer or SZC) which have better selectivity and tolerability than SPS 3
  • Optimize diuretic therapy if appropriate
  • Correct metabolic acidosis if present
  • Consider nephrology consultation for ongoing management 3, 5