Management of Hyperkalemia

FIGURE: Diagnostic approach to hyperkalemia - Harrison's Principles of Internal Medicine, 22E (2025)

Step 0 - First Rule Out Pseudohyperkalemia

Step 1 - Assess Severity and Obtain an ECG Immediately

• Harrison's Principles of Internal Medicine 22E (2025), p. 404
• Rosen's Emergency Medicine, p. 1367

Treatment: Three Stages

Stage 1 - Cardiac Membrane Stabilization (Immediate)

• Calcium raises the action potential threshold, restoring the difference between resting and threshold potentials - it reverses depolarization blockade without changing the resting membrane potential.
• Dose: 10 mL of 10% calcium gluconate IV over 2-3 minutes with continuous cardiac monitoring (alternatively: 3-4 mL of 10% calcium chloride - note CaCl has ~3x more elemental calcium but is more irritating to veins)
• Onset: 1-3 minutes; Duration: 30-60 minutes
• Repeat if no ECG improvement, or if ECG changes recur after initial improvement
• Caution in digoxin toxicity: Hypercalcemia potentiates digoxin cardiac toxicity. If calcium is judged necessary, dilute 10 mL of 10% calcium gluconate in 100 mL D5W and infuse over 20-30 min. The best treatment of hyperkalemia in acute digoxin toxicity is digoxin-specific Fab fragments.
• Harrison's, p. 404; Morgan & Mikhail's Clinical Anesthesiology 7e, p. 2179

Stage 2 - Redistribution of K+ into Cells (Rapid, Temporary)

A. Insulin + Glucose (First-line)

• Mechanism: Insulin activates the Na+/K+-ATPase pump, shifting K+ into cells
• Dose: 10 units regular insulin IV + 50 mL of 50% dextrose (D50W = 25 g glucose) immediately after
• Onset: 10-20 min; Peak: 30-60 min; Duration: 4-6 hours
• Important: Do NOT give bolus D50W without insulin - hypertonic glucose alone acutely worsens hyperkalemia via osmotic effects
• If glucose ≥200-250 mg/dL, give insulin without glucose, with close monitoring
• Follow with 10% dextrose infusion at 50-75 mL/h to prevent hypoglycemia

B. Beta-2 Agonists (Additive to insulin)

• Nebulized albuterol: 10-20 mg in 4 mL normal saline inhaled over 10 minutes
• Onset: ~30 min; Peak: ~90 min; Duration: 2-6 hours
• Effect is additive with insulin + glucose
• Caveat: ~20% of ESRD patients are resistant to beta-2 agonists - never rely on albuterol alone without insulin
• Side effects: tachycardia, hyperglycemia
• Use with caution in patients with known cardiac disease

C. Sodium Bicarbonate

• Older teaching: IV sodium bicarbonate drives K+ into cells via exchange for H+
• Current evidence: IV bicarbonate has no role in acute treatment of hyperkalemia as a rapid agent
• A delayed drop in plasma K+ (4-6 h) can be seen after sustained isotonic bicarbonate infusion in patients with metabolic acidosis
• Correct method if used: Infuse 150 mEq NaHCO3 in 1 L D5W (isotonic preparation) - do NOT give repeated hypertonic bolus ampules due to risk of hypernatremia and hypertonicity
• Harrison's 22E, p. 404

Stage 3 - Removal of Potassium from the Body (Definitive)

A. Loop Diuretics (if renal function adequate)

• Furosemide promotes renal K+ excretion
• Useful in volume-replete or hypervolemic patients with sufficient renal function
• May combine with IV saline (for hypovolemic patients with oliguria and decreased distal Na+ delivery) or isotonic bicarbonate

B. Potassium Binders (for subacute/chronic management)

• SPS and patiromer are not for urgent/acute hyperkalemia management due to delayed onset
• SZC has a faster onset and is preferred in many settings
• The newer binders (SZC, patiromer) allow patients on RAAS inhibitors (ACE-I, ARBs, MRAs) to continue therapy despite CKD or heart failure - a major clinical advance

C. Hemodialysis (Definitive)

• The most effective and reliable method to reduce plasma K+
• Peritoneal dialysis is considerably less effective
• Indicated for: severe or refractory hyperkalemia, AKI with impaired K+ excretion, patients unable to tolerate other therapies
• Amount of K+ removed depends on dialyzer type, blood and dialysate flow rates, duration, and the plasma-to-dialysate K+ gradient
• Harrison's 22E, p. 404; Morgan & Mikhail's, p. 2180

ECG Monitoring Summary

Peaked T waves → widened QRS + prolonged PR → loss of P waves → sine wave pattern → ventricular fibrillation / asystole

• Morgan & Mikhail's Clinical Anesthesiology 7e, p. 2179

Special Situations

Quick Reference Summary Table

Recent Evidence Note

Levipil (Levetiracetam) - Pediatric Dosing

Key pharmacokinetic point in children: Clearance is 30-40% higher and half-life shorter (~5-6 h vs. 7.2 h in adults), so children require higher doses on a mg/kg basis than adults.

Age-Stratified Dosing (Oral)

The lowest effective dose should always be used. Dose changes should not exceed the stated increments.

IV / Infusion Dose (Levetiracetam Injection)

• Children 4 years and older: Same mg/kg dose as oral, given as a 15-minute IV infusion, divided into 2 doses/day
• Acute seizures / status epilepticus (off-label loading): 20-60 mg/kg IV over 15 minutes (used in practice; max commonly 3000 mg)
• For head trauma prophylaxis (Tintinalli's): 20 mg/kg IV (max 500 mg/dose) for the first week

Levipil Formulations Available in India

Practical Titration Example (Child, 20 kg, age 6 years)

Important Clinical Notes

• Twice-daily dosing is standard for all age groups
• Renal dose adjustment is required: levetiracetam is ~66% renally cleared. Reduce dose if eGFR <80 mL/min/1.73m²
• No hepatic adjustment needed (minimal hepatic metabolism)
• Enzyme-inducing AEDs (e.g., carbamazepine) increase levetiracetam clearance by ~22% - may need higher doses
• Behavioral side effects (irritability, aggression) are more common in children than adults; inform parents
• No significant drug-drug interactions with common AEDs (valproate, lamotrigine, topiramate, carbamazepine)
• Neonates (<1 month): not formally approved; used cautiously at 10-20 mg/kg/day in some NICUs