What is the immediate treatment for hyperkalemia?

Immediate Treatment for Hyperkalemia

The immediate treatment for hyperkalemia requires a three-step approach: cardiac membrane stabilization with intravenous calcium, shifting potassium into cells with insulin/glucose and albuterol, and eliminating potassium from the body through diuretics or dialysis. 1

Assessment of Severity

• Hyperkalemia is classified as mild (5.0-5.9 mEq/L), moderate (6.0-6.4 mEq/L), or severe (≥6.5 mEq/L) 1, 2
• ECG changes (peaked T waves, flattened P waves, prolonged PR interval, widened QRS) indicate urgent treatment regardless of potassium level 1, 2
• Severe hyperkalemia (≥6.5 mEq/L) is life-threatening and requires immediate intervention 1

Step 1: Cardiac Membrane Stabilization

• Administer intravenous calcium to protect the heart from arrhythmias:
  • 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 1, 2
• Effects begin within 1-3 minutes but are temporary (30-60 minutes) 1
• Important: Calcium does not lower serum potassium but protects against arrhythmias 1
• Caution: In patients with malignant hyperthermia, calcium should only be used in extreme cases as it may contribute to calcium overload of the myoplasm 2

Step 2: Shift Potassium into Cells

• Administer insulin with glucose:
  • 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 1
  • Onset within 15-30 minutes, effect lasts 4-6 hours 1, 2
• Add nebulized albuterol:
  • 10-20 mg over 15 minutes 1
  • Augments the effect of insulin/glucose 3
• Consider sodium bicarbonate:
  • 50 mEq IV over 5 minutes 1
  • Most effective in patients with concurrent metabolic acidosis 1, 2
  • Promotes potassium excretion through increased distal sodium delivery 2

Step 3: Eliminate Potassium from Body

• For patients with adequate renal function:
  • Loop diuretics (furosemide: 40-80 mg IV) 1, 2
• For all patients:
  • Cation exchange resins (sodium polystyrene sulfonate/Kayexalate: 15-50 g orally or rectally with sorbitol) 1
  • Consider newer potassium binders (patiromer, sodium zirconium cyclosilicate) which are safer alternatives 1, 2
• For severe hyperkalemia or renal failure:
  • Hemodialysis is the most effective method 1, 2

Important Clinical Considerations

• Temporary measures (insulin/glucose, albuterol) provide only transient effects (1-4 hours); rebound hyperkalemia can occur after 2 hours 1
• Monitor potassium levels closely during treatment to avoid overcorrection and hypokalaemia 1
• Review and adjust medications that may contribute to hyperkalemia (ACE inhibitors, ARBs, MRAs, NSAIDs, beta-blockers) 1, 2
• Patients with chronic kidney disease, heart failure, or diabetes are at higher risk for hyperkalemia and require more frequent monitoring 2, 4
• For chronic hyperkalemia management, consider a multidisciplinary approach involving specialists and primary care physicians 2, 4

Common Pitfalls and Caveats

• Failure to recognize ECG changes can lead to delayed treatment and cardiac complications 1, 5
• Administering insulin without glucose can cause severe hypoglycemia, especially in malnourished patients 6
• Relying solely on temporary measures without addressing elimination of potassium can lead to rebound hyperkalemia 1
• Sodium polystyrene sulfonate can cause intestinal necrosis, particularly in postoperative patients or those with ileus 2, 6
• Overcorrection of hyperkalemia can lead to hypokalaemia, which carries its own risks of arrhythmias 1