What is the immediate treatment for hyperkalemia?

Immediate Treatment for Hyperkalemia

For life-threatening hyperkalemia (≥6.5 mEq/L or any ECG changes), immediately administer intravenous calcium to stabilize the cardiac membrane, followed by insulin with glucose and nebulized albuterol to shift potassium intracellularly, then initiate definitive potassium removal strategies. 1

Severity Assessment

Before initiating treatment, classify the severity and verify the result is not pseudohyperkalemia from hemolysis or poor phlebotomy technique 2:

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

ECG changes mandate urgent treatment regardless of potassium level 1. Look specifically for peaked T waves, flattened P waves, prolonged PR interval, and widened QRS complexes 1, 2. However, ECG findings are highly variable and less sensitive than laboratory values, so do not rely solely on ECG 2.

Three-Step Treatment Algorithm

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

Administer intravenous calcium first to protect against fatal arrhythmias 1:

• Calcium chloride (10%): 5-10 mL (500-1000 mg) IV over 2-5 minutes - preferred option as it provides more rapid increase in ionized calcium than calcium gluconate 1
• Calcium gluconate (10%): 15-30 mL IV over 2-5 minutes - alternative if only peripheral IV access available 1

Critical considerations for calcium administration 1:

• Effects begin within 1-3 minutes but last only 30-60 minutes 1, 2
• Does not lower serum potassium - only stabilizes cardiac membranes 1
• Administer through central line when possible, as calcium chloride extravasation causes severe tissue injury 1
• Monitor heart rate during infusion and stop if symptomatic bradycardia occurs 1
• Repeat dose if no ECG improvement within 5-10 minutes 2

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 1:

• 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 1
• Onset within 15-30 minutes, effects last 4-6 hours 1
• Can be repeated every 4-6 hours if hyperkalemia persists, monitoring glucose and potassium every 2-4 hours 2
• Verify potassium is not below 3.3 mEq/L before administering 2
• Patients at highest risk for hypoglycemia: low baseline glucose, no diabetes, female sex, impaired renal function 2

Nebulized albuterol 1:

• 10-20 mg nebulized over 15 minutes 1
• Onset within 15-30 minutes, effects last 2-4 hours 1, 2
• Can reduce serum potassium by approximately 0.5-1.0 mEq/L 1

Sodium bicarbonate - ONLY if concurrent metabolic acidosis present 1, 2:

• 50 mEq IV over 5 minutes 1
• Use only when pH <7.35 and bicarbonate <22 mEq/L 2
• Effects take 30-60 minutes to manifest 2
• Do not use in patients without acidosis - it is ineffective and potentially harmful 2

Step 3: Eliminate Potassium from Body (Definitive Treatment)

Loop diuretics 1:

• Furosemide 40-80 mg IV to increase renal potassium excretion 1
• Only effective in patients with adequate renal function 1

Potassium binders 1:

• Newer agents (patiromer or sodium zirconium cyclosilicate) are preferred over sodium polystyrene sulfonate 1, 2
• Sodium zirconium cyclosilicate: 10g three times daily for 48 hours, then 5-15g once daily - onset within 1 hour 2
• Patiromer: 8.4g once daily, titrated up to 25.2g daily - onset ~7 hours 2
• Avoid sodium polystyrene sulfonate (Kayexalate) for acute management due to delayed onset and risk of bowel necrosis 2

Hemodialysis 1:

• Most effective and reliable method for severe hyperkalemia 1, 3
• Indications: severe cases unresponsive to medical management, oliguria, end-stage renal disease 2
• Should be initiated urgently in refractory cases 1

Critical Pitfalls to Avoid

• Remember that calcium, insulin, and beta-agonists are temporizing measures only - they do not remove potassium from the body 2
• Rebound hyperkalemia can occur after 2-4 hours when temporary measures wear off 1
• Always administer glucose with insulin to prevent life-threatening hypoglycemia 2
• Never use sodium bicarbonate without metabolic acidosis - it is only indicated when acidosis is present 2
• Do not discontinue RAAS inhibitors permanently in patients with cardiovascular disease - use potassium binders to maintain these life-saving medications 1, 2
• Verify the result is not pseudohyperkalemia from hemolysis, repeated fist clenching, or poor technique before initiating aggressive treatment 2

Monitoring Protocol

• Check potassium levels every 2-4 hours after initial treatment 2
• Continuous cardiac monitoring is mandatory during acute treatment 2
• Monitor glucose closely when using insulin to prevent hypoglycemia 2
• For patients on RAAS inhibitors, reassess potassium 7-10 days after starting or increasing doses 2