Hyperkalemia Management

1. Confirm and risk-stratify

• Repeat/confirm the level to rule out pseudohyperkalemia (hemolyzed sample, prolonged tourniquet time, marked thrombocytosis/leukocytosis).
• Get a 12-lead ECG immediately - severity is judged by ECG changes as much as by the absolute K+ level.
• ECG progression: peaked T waves → PR prolongation/flattened P waves → widened QRS → sine-wave pattern → VF/asystole.
• Severe = K+ > 6.5 mEq/L and/or any ECG changes; this triggers emergency treatment regardless of the exact number (Comprehensive Clinical Nephrology, 7th ed., p. 1637-1639; Rosen's Emergency Medicine, p. 2161-2169).

2. Three-pronged emergency treatment

• IV calcium (calcium gluconate 1-2 g, or calcium chloride via central line) - antagonizes the membrane effects of hyperkalemia within 1-3 minutes, lasting 20-60 minutes; repeat if ECG changes persist.
• Give as a slow infusion (20-30 min) in patients on digoxin, since hypercalcemia can potentiate digoxin toxicity. Never mix with bicarbonate-containing solutions (precipitates as calcium carbonate) - Comprehensive Clinical Nephrology, 7th ed., p. 1640.

• Regular insulin IV (10 units, e.g., 0.1 U/kg) with dextrose (25-50 g, or 0.5 g/kg in children) to prevent hypoglycemia - onset 10-20 min, effect lasts 4-6 hours.
• Nebulized/IV albuterol (β2-agonist) - additive effect with insulin.
• Sodium bicarbonate - only if the patient is frankly acidotic (pH < 7.2) or has meaningful residual renal function; not a reliable stand-alone therapy and can worsen volume overload or cause acute hypernatremia in anuric patients (Comprehensive Clinical Nephrology, p. 1637).

• Loop diuretics (furosemide) if the patient still makes urine and isn't volume-depleted.
• Potassium binders: sodium/calcium polystyrene sulfonate (Kayexalate), or newer agents patiromer and sodium zirconium cyclosilicate (SZC) - slower onset (hours), better suited for subacute/chronic management.
• Hemodialysis - most effective and definitive option, indicated for severe/refractory hyperkalemia, oliguric AKI, or when other measures fail (Katzung's Basic and Clinical Pharmacology, 16th ed., p. 2417; Rosen's, p. 2161-2169).

3. Treat the underlying cause

• Review medications (ACEi/ARBs, MRAs, NSAIDs, trimethoprim, succinylcholine - avoid in hyperkalemic patients), renal function, and consider adrenal insufficiency, tumor lysis, rhabdomyolysis, or digoxin toxicity (treat with IV magnesium or digoxin-specific Fab fragments if suspected) - Tintinalli's Emergency Medicine.

4. Chronic/recurrent hyperkalemia (e.g., CKD or heart failure on RAAS inhibitors)

• Dietary potassium restriction, review of RAAS inhibitor/MRA doses, and long-term use of potassium binders (patiromer, SZC) allow many patients to stay on renin-angiotensin-aldosterone system inhibitors rather than stopping them outright, per recent meta-analyses.

• A 2025 systematic review/meta-analysis in Drugs found novel potassium binders effectively reduce hyperkalemia and help optimize continuation of RAAS inhibitor therapy in CKD/heart failure (PMID: 40542996).
• A 2025 Resuscitation systematic review/meta-analysis on acute pharmacological treatment (insulin, albuterol) reinforces insulin/glucose as the primary rapid-acting therapy, with more nuanced evidence on optimal albuterol dosing and combination strategies (PMID: 39761907).
• A 2025 European interdisciplinary consensus (GUARDIAN-HK) gives updated recommendations specifically for recurrent hyperkalemia management in CKD/HF populations (PMID: 40685253) - worth consulting if managing a chronic relapsing case rather than a single acute episode.

• Regular insulin 10 units IV (some protocols weight-base at 0.1 unit/kg)
• Dextrose 25 g IV — this is one ampule of D50W (50% dextrose, 50 mL)

• If the patient's blood glucose is already elevated (>250 mg/dL), dextrose can be omitted and insulin given alone, since exogenous glucose isn't needed to avoid hypoglycemia.
• Many protocols now also follow with a D10 infusion (e.g., 50-75 mL/hr for 1-2 hours) after the bolus, because delayed hypoglycemia is common (occurs in up to ~15-20% of patients) when only the bolus D50 is given without a follow-up drip.
• Pediatric dosing: insulin 0.1 units/kg with dextrose 0.5 g/kg IV.
• Recheck glucose ~30-60 minutes after the bolus regardless of regimen, given the hypoglycemia risk.