Initial Treatment for Hyperkalemia
For acute hyperkalemia with ECG changes or potassium ≥6.5 mEq/L, immediately administer IV calcium gluconate (15-30 mL of 10% solution over 2-5 minutes) to stabilize cardiac membranes, followed by insulin (10 units regular insulin with 50 mL of 50% dextrose IV) and nebulized albuterol (20 mg) to shift potassium intracellularly. 1, 2
Immediate Assessment
Before initiating treatment, verify the result is not pseudohyperkalemia from hemolysis, repeated fist clenching, or poor phlebotomy technique by repeating the measurement with proper technique or arterial sampling 1, 2. Obtain an ECG immediately to look for peaked T waves, flattened P waves, prolonged PR interval, and widened QRS complexes, though these findings can be highly variable and less sensitive than laboratory values 1.
Severity Classification
ECG changes indicate urgent treatment regardless of potassium level 1.
Step-by-Step Acute Treatment Algorithm
Step 1: Cardiac Membrane Stabilization (if K+ >6.5 mEq/L or ANY ECG changes)
Administer IV calcium immediately 1, 2:
- Calcium gluconate (10%): 15-30 mL IV over 2-5 minutes 1, 3, 2
- Calcium chloride (10%): 5-10 mL IV over 2-5 minutes (alternative) 1, 3
The effects begin within 1-3 minutes but are temporary (30-60 minutes) and do not reduce serum potassium 1. Repeat dosing may be necessary if no ECG improvement within 5-10 minutes 1. Continuous cardiac monitoring is mandatory during and after administration 1.
Critical caveat: Calcium does not remove potassium from the body—it only temporizes 1, 2.
Step 2: Shift Potassium Intracellularly (for K+ ≥6.0 mEq/L)
Administer all three therapies simultaneously for maximum effect:
Insulin with glucose: 10 units regular insulin IV with 25g glucose (50 mL of 50% dextrose) 1, 3, 2
Nebulized albuterol/salbutamol: 10-20 mg in 4 mL nebulized over 15 minutes 1, 3, 4
Sodium bicarbonate: 50 mEq IV over 5 minutes ONLY if concurrent metabolic acidosis is present (pH <7.35, bicarbonate <22 mEq/L) 1, 3, 2
Critical caveat: Insulin, albuterol, and bicarbonate do not remove potassium from the body—they only shift it temporarily 1, 2.
Step 3: Potassium Elimination
For patients with adequate kidney function:
For definitive potassium removal:
- Hemodialysis is the most reliable and effective method for severe hyperkalemia, especially in patients with renal failure, oliguria, or cases unresponsive to medical management 1, 3, 5
For subacute/chronic management:
Newer potassium binders (preferred):
Sodium polystyrene sulfonate (Kayexalate): Reserved for subacute treatment only due to delayed onset of action and risk of bowel necrosis 1, 6, 4
Mild Hyperkalemia (5.0-5.5 mEq/L without ECG changes)
Do not initiate acute interventions (calcium, insulin, or albuterol) for mild hyperkalemia without ECG changes or symptoms 1. Instead:
- Eliminate contributing medications: NSAIDs, trimethoprim, heparin, beta-blockers, potassium supplements, salt substitutes 1
- Consider loop diuretics (furosemide) to enhance urinary potassium excretion if adequate renal function exists 1
- Avoid potassium supplements and salt substitutes 1
Critical Pitfalls to Avoid
- Do not rely solely on ECG findings—they are highly variable and less sensitive than laboratory tests 1, 2
- Do not use sodium bicarbonate without metabolic acidosis—it is only indicated when acidosis is present 1, 2
- Always administer glucose with insulin to prevent hypoglycemia 1, 2
- Remember that calcium, insulin, and beta-agonists do not remove potassium—they only temporize 1, 2
- Do not discontinue RAAS inhibitors permanently in patients with cardiovascular disease or CKD—use potassium binders instead to maintain these life-saving medications 1