How to manage severe hyperkalemia?

Management of Severe Hyperkalemia (Serum Potassium 155 mEq/L)

A serum potassium of 155 mEq/L represents a critical laboratory error or sample hemolysis, as this level is physiologically impossible and incompatible with life. Immediate repeat testing is required while simultaneously initiating emergency treatment for presumed severe hyperkalemia. 1, 2

Step 1: Confirm and Assess

• Request immediate repeat potassium measurement to rule out laboratory error or hemolysis 1
• Obtain urgent ECG to assess for hyperkalemic changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) 3
• Establish IV access and place patient on continuous cardiac monitoring 3
• Severe hyperkalemia is defined as potassium ≥6.5 mEq/L and requires immediate intervention 3, 1

Step 2: Cardiac Membrane Stabilization (Immediate)

• Administer calcium chloride 10%: 5-10 mL (500-1000 mg) IV over 2-5 minutes OR calcium gluconate 10%: 15-30 mL IV over 2-5 minutes 3, 1
• Effects begin within minutes but are temporary (30-60 minutes) and do not lower serum potassium 1
• Calcium stabilizes cardiac membranes, protecting against arrhythmias 3, 1

Step 3: Shift Potassium into Cells (Within minutes)

• Administer insulin with glucose: 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 3, 1
• Add nebulized albuterol: 10-20 mg over 15 minutes 3, 1
• Consider sodium bicarbonate: 50 mEq IV over 5 minutes, especially if metabolic acidosis is present 3, 2
• Effects of insulin/glucose begin within 15-30 minutes and last 4-6 hours 1

Step 4: Eliminate Potassium from Body

• For patients with adequate renal function, administer furosemide 40-80 mg IV 3, 1
• Consider hemodialysis, which is the most effective method for severe hyperkalemia, especially in patients with renal failure 3, 1
• Newer potassium binders (patiromer, sodium zirconium cyclosilicate) are preferred over sodium polystyrene sulfonate (Kayexalate) due to better safety profile 2, 4
• If newer binders unavailable, administer sodium polystyrene sulfonate: 15-50 g orally or rectally with sorbitol 3, 5

Important Clinical Considerations

• Temporary measures (insulin/glucose, albuterol) provide only transient effects (1-4 hours); rebound hyperkalemia can occur 1, 2
• Monitor potassium levels frequently during treatment 1
• Review and adjust medications that may contribute to hyperkalemia (ACE inhibitors, ARBs, NSAIDs, potassium-sparing diuretics) 2, 6
• Sodium polystyrene sulfonate should not be used as emergency treatment due to delayed onset of action 5
• Avoid sodium polystyrene sulfonate in patients with bowel obstruction or impaired motility due to risk of intestinal necrosis 5

Special Situations

• For patients with renal failure, dialysis is the definitive treatment 3, 7
• For patients with metabolic acidosis, sodium bicarbonate may be more effective 2
• For patients with cardiac conditions, calcium administration is critical to prevent arrhythmias 3, 1

Follow-up Management

• Identify and address underlying cause of hyperkalemia 4
• Consider chronic management with newer potassium binders if recurrent hyperkalemia is a concern 2, 4
• Implement dietary potassium restrictions as appropriate 7