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Dialysis‐dependent patients are already at risk for hyperkalemia; those who miss one or more regular sessions incur even more risk. If an ESRD patient presents with arrhythmia (peaked T‐waves, QRS widening, ventricular fibrillation, or ventricular tachycardia) or is unstable with hypotension or cardiac arrest, empiric management of hyperkalemia is warranted [12, 14, 38].

Intravenous calcium is administered for stabilizing the cardiac membrane. This therapy has a duration of action between 30 and 60 minutes, which may necessitate the need for redosing depending on transport times. Calcium gluconate is dosed at 1,000 mg (10 mL of 10% solution) IV over 2‐3 minutes. Calcium chloride can also be dosed at 500‐1000 mg (5‐10 mL of 10% solution) IV over 2‐3 minutes. Both agents require continuous cardiac monitoring and can be repeated after 5 minutes if ECG changes persist or recur [12, 14, 38].

Sodium bicarbonate can help to alkalinize the blood and promote the shift of potassium to intracellular spaces. This is most effectively administered as an isotonic infusion of a bicarbonate solution with concentration 150 mmol/L (typically three ampules in a liter of D5W), being mindful of the potential for fluid overload. Hypertonic formulations, conversely, have been shown to have a neutral effect on potassium as the solute drag that occurs with the hyperosmolar solution counterproductively increases extracellular potassium. The routine administration of hypertonic sodium bicarbonate is no longer recommended in the prehospital setting. There are data that show benefit in its use in hyperkalemic patients with severe acidosis (pH < 7.2) and in those with a contraindication to calcium (e.g., digoxin toxicity), acting to temporarily stabilize cardiac membranes. The dosing is 50 mEq (50 mL of 8.4% solution, commonly distributed as an ampule/needle combination for EMS and code carts) to be given IV over 5 minutes. This can be repeated every 10‐15 minutes if ECG changes persist or recur. Caution should be taken to ensure the IV line is flushed between calcium and sodium bicarbonate doses, as calcium carbonate can form and precipitate [12, 14, 38].

Albuterol can be given in the usual fashion to shift potassium out of the plasma. It is easily administered to the patient and has the advantage of being noninvasive. It can be given as a continuous nebulizer treatment with 10‐20 mg of albuterol solution in 4 mL of saline over 10 minutes. However, the onset of action is not immediate, the potassium level will rebound if not otherwise treated in the next few hours, and tachyarrhythmia is a possible consequence [12, 14, 38].

Regardless of the medication(s) used in the field, the ESRD patient with hyperkalemia will require definitive management, as these therapies serve only to either prevent arrhythmia or temporarily shift potassium from the plasma. The total body potassium does not decrease. During subsequent transitions of care, it is imperative to communicate clearly about what treatment has been administered. Otherwise, serum potassium assays may be falsely reassuring to the next clinical team.