Be alert for cyanide toxicity when using sodium nitroprusside * Toxicity from sodium nitroprusside can be seen in as little as 2-4 hours with rates > 4.0 mcg/kg/min * Patients with hepatic and renal dysfunction are at greatest risk * Clinical signs of toxicity include altered mental status (agitation, restlessness), tachycardia, ventricular arrhythmias, and eventually hypotension * The classic anion-gap metabolic acidosis is a pre-terminal event - do not wait for this to develop to raise suspicion of toxicity! Reference: Marcucci L, ed. Avoiding common ICU errors. Philadelphia; Lippincott Williams & Wilkins; 2007:148-9.
