What is the treatment for hyperkalemia?

Treatment of Hyperkalemia

Hyperkalemia with potassium ≥6.5 mEq/L or any ECG changes requires immediate three-step emergency treatment: cardiac membrane stabilization with IV calcium, intracellular potassium shift with insulin/glucose and beta-agonists, followed by potassium elimination from the body. 1, 2

Severity Classification

Before initiating treatment, classify the severity and assess for ECG changes:

• Mild hyperkalemia: 5.0-5.9 mEq/L 1, 2
• Moderate hyperkalemia: 6.0-6.4 mEq/L 1, 2
• Severe hyperkalemia: ≥6.5 mEq/L (life-threatening emergency) 1, 2

ECG changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) mandate urgent treatment regardless of potassium level. 1, 2 However, ECG changes are present in only 14% of hyperkalemia cases, so their absence does not exclude severe hyperkalemia. 3

Critical pitfall: Always exclude pseudo-hyperkalemia from hemolysis or improper blood sampling by repeating the measurement with appropriate technique or arterial sampling before initiating aggressive treatment. 1, 4

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

Administer IV calcium chloride (10%): 5-10 mL (500-1000 mg) IV over 2-5 minutes as the preferred first-line agent. 1, 2 Calcium chloride provides more rapid increase in ionized calcium concentration than calcium gluconate, making it more effective in critically ill patients. 1

Alternative: Calcium gluconate (10%): 15-30 mL IV over 2-5 minutes if calcium chloride unavailable. 1, 2

Key considerations for calcium administration:

• Effects begin within 1-3 minutes but are temporary, lasting only 30-60 minutes 1, 2
• Does not lower serum potassium—only protects against arrhythmias 1, 2
• 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
• In malignant hyperthermia with hyperkalemia, use calcium only in extremis due to risk of myoplasmic calcium overload 4

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

Administer all three agents simultaneously for maximum effect:

Insulin with Glucose (Primary Agent)

Give 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes. 1, 2 This is the standard dose, though some protocols use 0.1 units/kg (approximately 5-7 units in adults). 4

Critical monitoring for insulin:

• Verify potassium is not below 3.3 mEq/L before administering insulin 4
• Monitor glucose and potassium every 2-4 hours after administration 4
• Can repeat every 4-6 hours if hyperkalemia persists or recurs 4
• Patients at highest risk for hypoglycemia: low baseline glucose, no diabetes history, female sex, altered renal function 4

Nebulized Beta-2 Agonist

Administer albuterol 10-20 mg nebulized over 15 minutes. 1, 2 This reduces serum potassium by approximately 0.5-1.0 mEq/L. 2

Sodium Bicarbonate (Only if Metabolic Acidosis Present)

Give 50 mEq IV over 5 minutes only in patients with concurrent metabolic acidosis (pH <7.35, bicarbonate <22 mEq/L). 1, 4 Sodium bicarbonate is ineffective without acidosis and should not be used routinely. 1, 4 Effects take 30-60 minutes to manifest. 4

Important warning: These temporary measures provide only transient effects (4-6 hours), and rebound hyperkalemia can occur after 2 hours. 1 Initiate potassium-lowering agents early to prevent rebound. 1

Step 3: Eliminate Potassium from Body (Definitive Treatment)

For Patients with Adequate Renal Function

Administer furosemide 40-80 mg IV to increase urinary potassium excretion. 1, 2 Loop diuretics are only effective in patients with adequate kidney function. 1, 2

Potassium Binders (Not for Emergency Use)

Sodium polystyrene sulfonate (Kayexalate) should NOT be used as emergency treatment due to delayed onset of action. 5 The FDA label explicitly states this limitation. 5

For non-emergency chronic management:

• Sodium polystyrene sulfonate: 15-50 g orally or rectally 2
• Warning: Risk of intestinal necrosis and serious GI events; avoid concomitant sorbitol 5
• Newer, safer alternatives: Patiromer (Veltassa) and sodium zirconium cyclosilicate (SZC/ZS-9) are preferred over traditional resins 1, 2, 4

Hemodialysis

Hemodialysis is the most effective method for severe hyperkalemia, especially in renal failure or cases refractory to medical treatment. 1, 2, 6 This is the most reliable method to remove potassium from the body. 6

Management of Chronic/Recurrent Hyperkalemia

For Patients on RAAS Inhibitors (ACE Inhibitors, ARBs, Mineralocorticoid Antagonists)

Potassium 5.0-6.4 mEq/L:

• Initiate approved potassium-lowering agent 1, 4
• Maintain RAAS inhibitor therapy unless alternative treatable cause identified 1, 4
• Monitor potassium levels closely 1

Potassium >6.5 mEq/L:

• Discontinue or reduce RAAS inhibitor temporarily 1, 4
• Initiate potassium-lowering agent 1, 4
• Monitor potassium levels closely 1

Rationale: In patients with cardiovascular disease, maintaining RAAS inhibitors with potassium binders is preferable to discontinuing these life-saving medications. 1, 4

Additional Chronic Management Strategies

• Review and adjust medications contributing to hyperkalemia (ACE inhibitors, ARBs, MRAs, NSAIDs, beta-blockers) 1, 4
• Ensure effective diuretic therapy 7
• Correct metabolic acidosis if present 7
• Reassess dietary potassium restriction—focus on reducing nonplant sources rather than blanket restriction 7
• Consider SGLT2 inhibitors to assist in maintaining RAAS inhibitor use 7

Monitoring and Follow-Up

• Monitor potassium levels every 2-4 hours during acute treatment 4
• Assess for rebound hyperkalemia after temporary measures wear off (typically 2-6 hours) 1
• For patients on RAAS inhibitors, check potassium 7-10 days after starting or increasing doses 4
• Higher-risk patients (CKD, heart failure, diabetes) require more frequent monitoring 4