What is the treatment for hyperkalemia?

Treatment for Hyperkalemia

For severe hyperkalemia (≥6.5 mEq/L) or any potassium level with ECG changes, immediately administer intravenous calcium chloride 10% (5-10 mL over 2-5 minutes) to stabilize cardiac membranes, followed within 15 minutes by insulin 10 units with 25g glucose and nebulized albuterol 10-20 mg to shift potassium intracellularly. 1, 2

Severity Classification and Initial Assessment

Before initiating treatment, verify the result is not pseudohyperkalemia from hemolysis, repeated fist clenching, or poor phlebotomy technique by repeating the measurement with proper technique or arterial sampling. 1, 3

Severity definitions:

• Mild: 5.0-5.9 mEq/L 1, 3
• Moderate: 6.0-6.4 mEq/L 1, 3
• Severe: ≥6.5 mEq/L (life-threatening) 1, 3

Critical point: ECG changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) indicate urgent treatment regardless of potassium level. 1, 3 However, absent or atypical ECG changes do not exclude the necessity for immediate intervention. 4

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

Calcium chloride is preferred over calcium gluconate because it provides more rapid increase in ionized calcium concentration, making it more effective in critically ill patients. 1

Dosing:

• Calcium chloride 10%: 5-10 mL (500-1000 mg) IV over 2-5 minutes 1, 2
• Alternative - Calcium gluconate 10%: 15-30 mL IV over 2-5 minutes 1, 3

Administration considerations:

• Administer through central venous catheter when possible, as extravasation through peripheral IV may cause severe tissue injury 1
• Monitor heart rate during administration and stop if symptomatic bradycardia occurs 1
• Effects begin within 1-3 minutes but last only 30-60 minutes 1, 3
• Repeat dosing may be necessary if no ECG improvement within 5-10 minutes 3
• Does not lower serum potassium - only protects against arrhythmias 1, 3

Step 2: Shift Potassium into Cells (Onset 15-30 Minutes, Duration 4-6 Hours)

Use combination therapy for maximum effect:

Insulin with Glucose (First-line)

• 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 1, 2
• Onset: 15-30 minutes, duration: 4-6 hours 1, 3
• Can be repeated every 4-6 hours as needed, carefully monitoring glucose and potassium levels 3
• Critical: Verify potassium is not below 3.3 mEq/L before administering insulin 3
• Monitor for hypoglycemia, especially in patients with low baseline glucose, no diabetes history, female sex, or altered renal function 3

Nebulized Beta-2 Agonist (Adjunctive)

• Albuterol 10-20 mg nebulized over 15 minutes 1, 2
• Onset: 15-30 minutes, duration: 2-4 hours 1, 3
• Can reduce serum potassium by approximately 0.5-1.0 mEq/L 1

Sodium Bicarbonate (Only if Metabolic Acidosis Present)

• 50 mEq IV over 5 minutes 1
• Use ONLY in patients with concurrent metabolic acidosis (pH <7.35, bicarbonate <22 mEq/L) 1, 3
• Effects take 30-60 minutes to manifest 3
• Poor efficacy when used alone without acidosis 4

Important: These are temporizing measures only - rebound hyperkalemia can occur after 2 hours. 1

Step 3: Eliminate Potassium from Body (Definitive Treatment)

Loop Diuretics (If Adequate Renal Function)

• Furosemide 40-80 mg IV 1, 2
• Effective only in patients with preserved kidney function 1, 2
• Titrate to maintain euvolemia, not primarily for potassium management 3

Potassium Binders (Subacute to Chronic Management)

Newer agents are strongly preferred over sodium polystyrene sulfonate:

Sodium zirconium cyclosilicate (SZC/Lokelma):

• 10g three times daily for 48 hours, then 5-15g once daily for maintenance 3
• Onset: ~1 hour (fastest) 3
• Can be used for both acute (≥5.8 mEq/L) and chronic management 3

Patiromer (Veltassa):

• Starting dose: 8.4g once daily, titrate up to 25.2g daily based on potassium levels 3, 5
• Onset: ~7 hours 3
• FDA-approved for chronic hyperkalemia in adults and pediatric patients ≥12 years 5

Sodium polystyrene sulfonate (Kayexalate):

• 15-50g orally or rectally with sorbitol 1
• Should be avoided for acute management due to delayed onset of action and risk of bowel necrosis 3, 6
• FDA label explicitly states it should not be used as emergency treatment 6

Hemodialysis

• Most effective and reliable method for severe hyperkalemia, especially in renal failure 1, 2
• Reserved for severe cases unresponsive to medical management, oliguria, or end-stage renal disease 3, 2

Treatment Algorithm by Severity

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

1. Immediate: Calcium chloride 10%: 5-10 mL IV over 2-5 minutes 2
2. Within 15 minutes: Insulin 10 units + glucose 25g IV AND albuterol 10-20 mg nebulized 2
3. Concurrent: Loop diuretics or prepare for hemodialysis 2
4. Monitor: Potassium every 2-4 hours after initial administration 3

Moderate Hyperkalemia (K+ 6.0-6.4 mEq/L Without ECG Changes)

1. Insulin/glucose and albuterol for intracellular shift 2
2. Loop diuretics or potassium binders 2
3. Monitor potassium levels closely 2

Mild Hyperkalemia (K+ 5.0-5.9 mEq/L)

1. Review and discontinue offending medications (NSAIDs, trimethoprim, heparin, potassium supplements, salt substitutes) 3, 2
2. Initiate potassium binder for chronic management 2
3. Do not discontinue RAAS inhibitors - maintain therapy with potassium binders 3, 2
4. Check potassium within 1 week 3

Special Population: Patients on RAAS Inhibitors

Critical principle: Maintaining RAAS inhibitor therapy (ACE inhibitors, ARBs, mineralocorticoid antagonists) is preferable to discontinuing these life-saving medications. 1, 3

For K+ 5.0-6.5 mEq/L:

• Initiate approved potassium-lowering agent (patiromer or SZC) 1, 3
• Maintain RAAS inhibitor therapy unless alternative treatable etiology identified 1, 3
• Monitor potassium closely 1

For K+ >6.5 mEq/L:

• Discontinue or reduce RAAS inhibitor temporarily 1, 3
• Initiate potassium-lowering agent when levels >5.0 mEq/L 1, 3
• Restart RAAS inhibitor at lower dose with concurrent potassium binder therapy once stabilized 3

Monitoring Protocol

Initial monitoring:

• Check potassium within 1 week of starting or escalating RAAS inhibitors 3
• Reassess 7-10 days after initiating potassium binder therapy 3

Ongoing monitoring:

• Reassess at 1-2 weeks, 3 months, then every 6 months 3
• More frequent monitoring required in high-risk patients with CKD, heart failure, diabetes, or history of hyperkalemia 3
• Monitor closely for both efficacy and to prevent hypokalemia, which may be even more dangerous than hyperkalemia 3

Key Pitfalls to Avoid

• Do not rely solely on ECG findings - they are highly variable and less sensitive than laboratory tests 3
• Do not use sodium bicarbonate without metabolic acidosis - it is only indicated when acidosis is present 3
• Always administer glucose with insulin to prevent hypoglycemia 3
• Remember that calcium, insulin, and beta-agonists do not remove potassium - they only temporize 3
• Do not permanently discontinue ACE inhibitors - this leads to worse cardiovascular and renal outcomes 3
• Avoid sodium polystyrene sulfonate for acute management due to delayed onset and bowel necrosis risk 3, 6

Chronic Kidney Disease Considerations

Target potassium ranges vary by CKD stage:

• Stage 1-2 CKD: 3.5-5.0 mEq/L 3
• Stage 4-5 CKD: 3.3-5.5 mEq/L (broader range tolerated) 3
• Optimal target: 4.0-5.0 mEq/L to minimize mortality risk 3

Maintain RAAS inhibitors aggressively in proteinuric CKD using potassium binders, as these drugs slow CKD progression. 3