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, potassium binders, or hemodialysis. 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
• Severe hyperkalemia (≥6.5 mEq/L) is life-threatening and requires immediate intervention 1

Step 1: Cardiac Membrane Stabilization

• Administer intravenous calcium chloride (10%): 5-10 mL (500-1000 mg) IV over 2-5 minutes 1
• Alternative: calcium gluconate (10%): 15-30 mL IV over 2-5 minutes 1, 2
• Effects begin within 1-3 minutes but are temporary, lasting only 30-60 minutes 1, 2
• Important: Calcium does not lower serum potassium but protects against cardiac arrhythmias by stabilizing the cardiac membrane 1
• Caution: In patients with malignant hyperthermia and hyperkalemia, calcium should only be used in extremis as it may contribute to calcium overload of the myoplasm 2

Step 2: Shift Potassium into Cells

• Administer 10 units regular insulin IV with 25g glucose (50 mL of D50W) over 15-30 minutes 1, 3
• Onset of insulin/glucose effect is within 15-30 minutes, lasting 4-6 hours 1, 2
• Add nebulized albuterol: 10-20 mg over 15 minutes to enhance potassium shift into cells 1, 4
• Consider sodium bicarbonate (50 mEq IV over 5 minutes) only if concurrent metabolic acidosis is present 1, 2

Step 3: Eliminate Potassium from Body

• For patients with adequate renal function, administer loop diuretics such as furosemide 40-80 mg IV 1, 2
• Consider cation exchange resins such as sodium polystyrene sulfonate (Kayexalate): 15-50 g orally or rectally with sorbitol 1
• Newer potassium binders (patiromer and sodium zirconium cyclosilicate) are safer alternatives to traditional resins 1, 3
• Hemodialysis is the most effective method for severe hyperkalemia, especially in patients with renal failure 1, 3

Important Clinical Considerations

• Temporary measures (insulin/glucose, albuterol) provide only transient effects (1-4 hours), and 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, 5
• The presence of typical ECG changes or a rapid rise in serum potassium indicates potentially life-threatening hyperkalemia requiring immediate intervention 6
• Even absent or atypical ECG changes do not exclude the necessity for immediate intervention when serum potassium is >6.0 mEq/L 4

Treatment Algorithm for Hyperkalemia

1. Assess severity based on potassium level and ECG changes 1, 2
2. For severe hyperkalemia or ECG changes:
   • First: Administer IV calcium for cardiac protection 1
   • Second: Give insulin/glucose ± albuterol for intracellular shift 1, 4
   • Third: Initiate potassium elimination with diuretics, binders, or dialysis 1, 3
3. For moderate hyperkalemia without ECG changes:
   • Begin with insulin/glucose and consider other shifting strategies 2
   • Proceed with elimination strategies 2
4. For mild hyperkalemia:
   • Review medications and address underlying causes 2, 5
   • Consider oral potassium binders if persistent 3