Beta adrenoreceptor agonists administered by nebulization (e.g. albuterol nebulizers) are thought to be rapidly effective for lowering serum potassium levels in hyperkalemic patients. The mechanism is via a transient shift of the potassium intracellularly. It makes sense. But don't count on it. At least not much. The truth is that the beta-agonist nebs work much slower than you might think. Though they are quickly effective for bronchospasm, the potassium-shifting effect takes at least 30 minutes, and there's not much peak effect for perhaps as many as 60 minutes. Also, the "peak effect" is only approximately a 1.0 mmol/L reduction...and that's with a 20 mg dose. That's 8-times the normal dose than a typical albuterol neb (one of those albuterol "bullets" has 2.5 mg in 3 cc of solution, so a 20 mg dose would be 24 cc of the albuterol solution). The bottom line is that albuterol nebs are not really effective treatment, even transient, for patients with severe hyperkalemia. If you want do something while people are trying to gain IV access on a "tough stick," then it's certainly better than nothing. Ask the nurses or respiratory techs to start continuous nebs...but the IV calcium and insulin are still the key early temporizing measures to focus on until you've got elimination measures underway (kaexylate, hemodialysis, etc.). [Weisberg LS. Management of severe hyperkalemia. Crit Care Med 2008;36:3246-3251.]
