What is the emergency management of severe hyperkalemia (serum potassium ≥6.0 mmol/L) with electrocardiographic changes, including membrane stabilization, intracellular potassium shift, potassium removal, and criteria for dialysis?

Emergency Management of Severe Hyperkalemia (≥6.0 mmol/L) with ECG Changes

For severe hyperkalemia with ECG changes, immediately administer IV calcium gluconate 15-30 mL (or calcium chloride 5-10 mL) over 2-5 minutes to stabilize the cardiac membrane, followed simultaneously by insulin 10 units with 25g dextrose IV and nebulized albuterol 10-20 mg to shift potassium intracellularly, then initiate definitive potassium removal with loop diuretics or hemodialysis depending on renal function. 1

Step 1: Immediate Cardiac Membrane Stabilization (Within 1-3 Minutes)

Administer calcium first—this is your only protection against fatal arrhythmias while other therapies take effect. 1

• Calcium gluconate 10%: 15-30 mL IV over 2-5 minutes (preferred for peripheral access) 1
• OR calcium chloride 10%: 5-10 mL (500-1000 mg) IV over 2-5 minutes (more potent, requires central line) 1
• Onset: 1-3 minutes, Duration: 30-60 minutes 2
• Critical: Calcium does NOT lower potassium—it only temporarily stabilizes the cardiac membrane 2
• Repeat dose in 5-10 minutes if ECG changes persist 2
• Continuous cardiac monitoring is mandatory 2

Pitfall to Avoid:

Never delay calcium administration while waiting for repeat potassium levels if ECG changes are present—ECG abnormalities indicate urgent need regardless of the exact potassium value. 2

---

Step 2: Shift Potassium Intracellularly (Start Simultaneously with Calcium)

Give all three agents together for maximum effect—they work through different mechanisms and are synergistic. 1, 2

A. Insulin + Glucose (Most Effective)

• Regular insulin 10 units IV + 25g dextrose (50 mL D50W) 1
• Onset: 15-30 minutes, Peak: 30-60 minutes, Duration: 4-6 hours 1, 2
• Expected potassium reduction: 0.5-1.2 mEq/L 2
• Always give glucose with insulin to prevent life-threatening hypoglycemia 2
• Monitor glucose every 1-2 hours for 4-6 hours after administration 2

B. Nebulized Albuterol (Adjunctive)

• Albuterol 10-20 mg in 4 mL nebulized over 10-15 minutes 1, 2
• Onset: 30 minutes, Duration: 2-4 hours 2
• Expected potassium reduction: 0.5-1.0 mEq/L 2
• Can be repeated every 2 hours if needed 1

C. Sodium Bicarbonate (ONLY if Metabolic Acidosis Present)

• Sodium bicarbonate 50 mEq IV over 5 minutes 1
• ONLY use if pH <7.35 AND bicarbonate <22 mEq/L 2
• Onset: 30-60 minutes 2
• Ineffective as monotherapy without acidosis—do not waste time 2

Critical Monitoring:

• Recheck potassium within 1-2 hours after insulin/glucose administration 2
• Continue monitoring every 2-4 hours during acute treatment phase 2
• Remember: These are temporizing measures only—rebound hyperkalemia occurs within 4-6 hours as effects wear off 2

---

Step 3: Definitive Potassium Removal from the Body

Calcium and insulin only buy time—you must remove potassium or it will return. 2

A. Loop Diuretics (If Adequate Renal Function)

• Furosemide 40-80 mg IV 1, 2
• Requires eGFR >30 mL/min and adequate urine output 2
• Titrate to maintain euvolemia, not primarily for potassium management 2

B. Hemodialysis (Most Effective and Reliable)

Hemodialysis is the gold standard for severe hyperkalemia—it is the only method that reliably removes large amounts of potassium quickly. 1, 2

Absolute Indications for Dialysis:

• Severe hyperkalemia (K+ >6.5 mEq/L) unresponsive to medical therapy 2
• Oliguria or anuria 2
• End-stage renal disease 1, 2
• Ongoing potassium release (tumor lysis syndrome, rhabdomyolysis) 2
• Severe renal impairment (eGFR <15 mL/min) 3
• Persistent ECG changes despite medical management 2

Post-Dialysis Monitoring:

• Potassium can rebound 4-6 hours post-dialysis as intracellular potassium redistributes 4
• Monitor every 2-4 hours initially if severe hyperkalemia (>6.5 mEq/L) or ongoing release 4
• Obtain ECG post-dialysis to document resolution of peaked T waves, widened QRS, or prolonged PR interval 4

C. Potassium Binders (Subacute Management)

These are NOT for acute emergencies—onset is too slow. 2

• Sodium zirconium cyclosilicate (SZC/Lokelma): 10g three times daily for 48 hours, then 5-15g daily 2

  • Onset: ~1 hour (fastest binder) 2
  • Use for subacute management after initial stabilization 2

• Patiromer (Veltassa): 8.4g once daily, titrate up to 25.2g daily 2

  • Onset: ~7 hours 2
  • Reserved for chronic management 2

• Avoid sodium polystyrene sulfonate (Kayexalate): Associated with bowel necrosis, colonic ischemia, and lack of efficacy data 1, 2

---

Step 4: Medication Management During Acute Episode

Temporarily hold all potassium-raising medications—you can restart them later with potassium binders. 2

Medications to Hold Immediately:

• RAAS inhibitors (ACE inhibitors, ARBs, mineralocorticoid antagonists) if K+ >6.5 mEq/L 2, 4
• Potassium-sparing diuretics (spironolactone, amiloride, triamterene) 2
• NSAIDs 2
• Trimethoprim 2
• Heparin 2
• Beta-blockers 2
• Potassium supplements and salt substitutes 2

After Acute Resolution:

• Restart RAAS inhibitors at lower dose once K+ <5.0 mEq/L with concurrent potassium binder 2, 4
• Do NOT permanently discontinue RAAS inhibitors—they provide mortality benefit in cardiovascular and renal disease 2, 4
• Initiate patiromer or SZC to enable continuation of life-saving medications 2

---

Critical Pitfalls to Avoid

1. Never delay calcium administration while waiting for repeat labs if ECG changes are present 2
2. Never give insulin without glucose—hypoglycemia can be fatal 2
3. Never use sodium bicarbonate without documented metabolic acidosis—it is ineffective and wastes time 2
4. Remember: Calcium, insulin, and beta-agonists do NOT remove potassium—they only temporize 2
5. Do not rely solely on ECG findings—they are highly variable and less sensitive than laboratory tests 2
6. Never permanently discontinue RAAS inhibitors—use dose reduction plus potassium binders instead 2, 4

---

Monitoring Protocol

• Continuous cardiac monitoring during acute treatment 2
• Recheck potassium within 1-2 hours after insulin/glucose 2
• Continue monitoring every 2-4 hours until stabilized 2
• Check potassium and renal function within 7-10 days after medication adjustments 2
• Individualize monitoring frequency based on CKD stage, heart failure, diabetes, and history of hyperkalemia 2

---

Special Populations

Chronic Kidney Disease (Stage 4-5):

• Optimal potassium range is broader: 3.3-5.5 mEq/L for stage 4-5 CKD vs 3.5-5.0 mEq/L for stage 1-2 CKD 2
• Maintain RAAS inhibitors aggressively using potassium binders—these drugs slow CKD progression 2
• Dialysis is often required for definitive management in ESRD 2

Heart Failure:

• Both hyperkalemia and hypokalemia increase mortality—target 4.0-5.0 mEq/L 2
• Do not discontinue spironolactone unless K+ >6.0 mEq/L—it provides mortality benefit 4
• Reduce spironolactone dose by 50% at K+ >5.5 mEq/L 4

---

Team Approach

Optimal management involves cardiologists, nephrologists, primary care physicians, nurses, pharmacists, and dietitians working together. 2