Acute Hyperkalemia Treatment

Initial Assessment

• Obtain a 12‑lead ECG for every patient with suspected hyperkalemia; the presence of peaked T waves, flattened P waves, prolonged PR interval, or widened QRS mandates immediate therapy even when serum potassium is only mildly elevated. 3
• ECG abnormalities are less sensitive than serum potassium measurements and should not replace laboratory testing. 3
• Exclude pseudohyperkalemia caused by hemolysis, fist clenching, or poor phlebotomy technique before initiating treatment. 3
• Plasma potassium values are typically 0.1–0.4 mEq/L lower than serum values because of platelet potassium release during clotting. 3

Cardiac Membrane Stabilization

• Administer IV calcium gluconate 10 % (15–30 mL infused over 2–5 minutes) for any ECG changes or serum potassium ≥ 6.5 mEq/L; this stabilizes the cardiac membrane and prevents fatal arrhythmias but does not lower potassium levels. 3
• Calcium chloride 10 % (5–10 mL) may be used when central venous access is available. 3
• The protective effect of calcium lasts 30–60 minutes; a repeat dose (same volume) can be given if ECG abnormalities persist after 5–10 minutes. 3

Intracellular Potassium Shift

• Insulin‑glucose: Give 10 U regular insulin IV push followed by 25 g dextrose (50 mL D50W). This lowers serum potassium by 0.5–1.2 mEq/L within 30–60 minutes; the effect persists for 4–6 hours. Monitor glucose every 30–60 minutes to avoid hypoglycemia. 3
• Nebulized β‑agonist: Administer albuterol 10–20 mg in 4 mL nebulized over 10–15 minutes. Expected potassium reduction is 0.5–1.0 mEq/L within 30 minutes, lasting 2–4 hours; repeat dosing every 2 hours is possible and adds an additional 0.5–1.0 mEq/L beyond insulin‑glucose alone. 3
• Sodium bicarbonate (only with metabolic acidosis): Give 50 mEq IV over 5 minutes when pH < 7.35 and bicarbonate < 22 mEq/L. Onset of potassium lowering is 30–60 minutes, acting by increasing distal sodium delivery and correcting acidosis‑induced potassium release. It is ineffective without documented acidosis. 3

Definitive Potassium Removal

• Hemodialysis is the most reliable method for potassium removal. Absolute indications include:
  
  • Serum potassium > 6.5 mEq/L unresponsive to medical therapy,
  • End‑stage renal disease,
  • Severe renal impairment (eGFR < 15 mL/min).
• Loop diuretics (e.g., furosemide 40–80 mg IV) can be used when eGFR > 30 mL/min and urine output is adequate, promoting renal potassium excretion. Effectiveness is limited to non‑oliguric patients. 3

Potassium Binders (Sub‑acute/Chronic Use)

Chronic Hyperkalemia Management

• In patients on RAAS inhibitors with serum potassium 5.0–6.5 mEq/L, initiate an approved potassium‑lowering agent (SZC or patiromer) while continuing RAAS therapy; permanent discontinuation of RAAS inhibitors is discouraged. 3
• For potassium > 6.5 mEq/L, temporarily reduce or hold RAAS inhibitors, start a binder once potassium falls below 5.0 mEq/L, and then restart RAAS therapy at a lower dose with concurrent binder support. 3
• Dietary counseling should limit high‑potassium foods (e.g., bananas, oranges, potatoes, tomatoes, legumes, yogurt, chocolate) and avoid potassium‑containing salt substitutes. Evidence linking dietary potassium to serum levels is limited; focus on reducing non‑plant sources. 3
• Loop or thiazide diuretics can be used to promote urinary potassium excretion, titrated to maintain euvolemia rather than solely for potassium control. 3

Special Populations

• Chronic kidney disease (stage 4‑5): Patients may tolerate serum potassium 3.3–5.5 mEq/L; aim for 4.0–5.0 mEq/L to reduce mortality. Maintain RAAS inhibitors aggressively using potassium binders, which also slow CKD progression. 3
• Dialysis patients: Hemodialysis is definitive for severe hyperkalemia; target predialysis potassium 4.0–5.5 mEq/L. Adjust dialysate potassium (typically 2.0–3.0 mEq/L) based on trends. SZC can lower predialysis potassium from >6.0 mEq/L to <5.5 mEq/L. 3
• Heart failure patients: Both hypo‑ and hyperkalemia increase mortality; target serum potassium 4.0–5.0 mEq/L. Continue RAAS inhibitors and aldosterone antagonists with binder support; SGLT2 inhibitors may further reduce hyperkalemia risk. 3

Common Pitfalls

• Do not delay calcium administration while awaiting repeat potassium results when ECG changes are present; timely calcium is critical for cardiac protection. 3
• Never give insulin without concomitant glucose, as hypoglycemia can be fatal. 3
• Recognize that calcium, insulin, and β‑agonists are temporizing measures; they do not remove potassium from the body. 3
• Avoid sodium bicarbonate unless metabolic acidosis is documented; otherwise it provides no benefit. 3
• Do not use sodium polystyrene sulfonate (Kayexalate) due to its risk of bowel necrosis and limited efficacy. 3