What is the appropriate treatment with dosages for a patient presenting to the emergency department with acute hyperkalemia?

Emergency Department Treatment of Acute Hyperkalemia

For acute hyperkalemia in the emergency department, immediately administer IV calcium gluconate 15-30 mL (10% solution) over 2-5 minutes if ECG changes are present or potassium ≥6.5 mEq/L, followed by insulin 10 units IV with 25g dextrose and nebulized albuterol 10-20 mg to shift potassium intracellularly, then initiate potassium removal with loop diuretics or hemodialysis depending on renal function. 1

Immediate Assessment (First 5 Minutes)

• Obtain a 12-lead ECG immediately to identify peaked T waves, flattened P waves, prolonged PR interval, or widened QRS complexes, which indicate urgent treatment regardless of the exact potassium level 1
• Verify the potassium level is not pseudohyperkalemia from hemolysis, repeated fist clenching, or poor phlebotomy technique before initiating aggressive treatment 1
• Classify severity: mild (5.0-5.9 mEq/L), moderate (6.0-6.4 mEq/L), or severe (≥6.5 mEq/L) 1
• Do not delay treatment while waiting for repeat lab confirmation if ECG changes are present—ECG changes indicate urgent need regardless of the exact potassium value 1

Step 1: Cardiac Membrane Stabilization (Onset 1-3 Minutes)

Administer calcium immediately if potassium >6.5 mEq/L OR any ECG changes are present 1

• Calcium gluconate (10%): 15-30 mL IV over 2-5 minutes (preferred for peripheral access) 1
• Calcium chloride (10%): 5-10 mL IV over 2-5 minutes (use only in cardiac arrest or central line available) 1
• Monitor ECG continuously during and for 5-10 minutes after administration 1
• If no ECG improvement within 5-10 minutes, repeat the same dose 1
• Effects begin within 1-3 minutes but last only 30-60 minutes 1
• Critical caveat: Calcium does NOT lower serum potassium—it only temporarily stabilizes cardiac membranes 1

Special Considerations for Calcium Administration

• Never administer calcium through the same IV line as sodium bicarbonate, as precipitation will occur 1
• In patients with elevated phosphate levels (tumor lysis syndrome, rhabdomyolysis), use calcium cautiously as it increases risk of calcium-phosphate precipitation 1
• Pediatric dosing: 100-200 mg/kg/dose (calcium gluconate preferred for peripheral access) 1

Step 2: Intracellular Potassium Shift (Onset 15-30 Minutes)

Administer all three agents together for maximum effect 1

Insulin and Glucose (Most Effective)

• Insulin: 10 units regular insulin IV push 1
• Glucose: 25g dextrose (50 mL of 50% dextrose or D50W) IV push 1
• Onset of action: 15-30 minutes 1
• Duration of effect: 4-6 hours 1
• Monitor blood glucose at 30 minutes, 60 minutes, and every 2 hours for 6 hours to detect hypoglycemia 1
• Patients at higher risk for hypoglycemia: low baseline glucose, no diabetes history, female sex, altered renal function 1
• Can be repeated every 4-6 hours if hyperkalemia persists, with careful glucose monitoring 1

Beta-2 Agonist

• Albuterol: 10-20 mg nebulized in 4 mL over 10 minutes 1
• Onset of action: 15-30 minutes 1
• Duration of effect: 2-4 hours 1
• Use as adjunctive therapy with insulin/glucose 1

Sodium Bicarbonate (ONLY if Metabolic Acidosis Present)

• Indication: ONLY use if pH <7.35 and bicarbonate <22 mEq/L 1
• Dose: 50 mEq (50 mL of 8.4% solution) IV over 5 minutes 1
• Onset of action: 30-60 minutes 1
• Do NOT use in patients without metabolic acidosis—it is ineffective and wastes time 1
• Mechanism: promotes potassium excretion through increased distal sodium delivery and counters acidosis-induced potassium release 1

Step 3: Potassium Removal from Body

Loop Diuretics (If Adequate Renal Function)

• Furosemide: 40-80 mg IV 1
• Increases renal potassium excretion in patients with eGFR >30 mL/min 1
• Titrate to maintain euvolemia, not primarily for potassium management 1

Hemodialysis (Most Effective for Removal)

• Indications for emergent hemodialysis: 1
  • Severe hyperkalemia (>6.5 mEq/L) unresponsive to medical management
  • Oliguria or anuria
  • End-stage renal disease
  • Acute kidney injury with rising potassium despite treatment
• Hemodialysis is the most reliable and effective method for potassium removal 1
• Monitor for rebound hyperkalemia 4-6 hours post-dialysis as intracellular potassium redistributes 1

Potassium Binders (NOT for Acute Emergency)

Sodium polystyrene sulfonate (Kayexalate) should NOT be used for acute management 1, 2

• Delayed onset of action (hours to days) 1
• Risk of bowel necrosis, especially with sorbitol 1, 2
• Limited efficacy data 1
• Contraindicated in patients with obstructive bowel disease, neonates with reduced gut motility, or post-surgical patients without bowel movement 2

Newer potassium binders (for chronic management, NOT acute emergency):

• Sodium zirconium cyclosilicate (SZC/Lokelma): 10g three times daily for 48 hours, then 5-15g once daily for maintenance; onset ~1 hour 1
• Patiromer (Veltassa): 8.4g once daily, titrated up to 25.2g daily; onset ~7 hours 1
• These agents are for chronic hyperkalemia management to enable continuation of RAAS inhibitors, not for acute ED treatment 1

Step 4: Medication Review and Adjustment

Temporarily discontinue or reduce contributing medications: 1

• RAAS inhibitors (ACE inhibitors, ARBs, mineralocorticoid antagonists) if K+ >6.5 mEq/L 1
• Potassium-sparing diuretics (spironolactone, amiloride, triamterene) 1
• NSAIDs 1
• Trimethoprim 1
• Heparin 1
• Beta-blockers 1
• Potassium supplements and salt substitutes 1

Monitoring Protocol

• Check potassium levels every 2-4 hours during acute treatment phase until stabilized 1
• Continuous cardiac monitoring until potassium <6.0 mEq/L and ECG changes resolve 1
• Monitor glucose at 30 minutes, 60 minutes, and every 2 hours for 6 hours after insulin administration 1
• Reassess renal function and consider nephrology consultation 1

Critical Pitfalls to Avoid

• Do not rely solely on ECG findings—they are highly variable and less sensitive than laboratory tests 1
• Do not use sodium bicarbonate in patients without metabolic acidosis—it is only indicated when acidosis is present 1
• Ensure glucose is administered with insulin to prevent hypoglycemia 1
• Remember that calcium, insulin, and beta-agonists do NOT remove potassium from the body—they only temporize 1
• Never delay calcium administration while waiting for repeat potassium levels if ECG changes are present 1
• Do not use sodium polystyrene sulfonate for acute management—it has delayed onset and serious GI risks 1, 2

Treatment Algorithm Summary

1. ECG changes or K+ ≥6.5 mEq/L → IV calcium gluconate 15-30 mL immediately 1
2. Simultaneously give all three: Insulin 10 units + glucose 25g IV, albuterol 10-20 mg nebulized, ± bicarbonate 50 mEq IV (only if acidotic) 1
3. Initiate potassium removal: Furosemide 40-80 mg IV (if eGFR >30) OR arrange emergent hemodialysis (if severe/refractory/anuric) 1
4. Hold contributing medications and monitor potassium every 2-4 hours 1
5. Arrange follow-up with nephrology and primary care for chronic management with newer potassium binders if needed 1