Hypertension is a widespread entity in the surgical intensive care unit. Not only is the clinical spectrum varied, but the armamentarium available to the clinician is also wide-ranging. Sodium nitroprusside, a potent vasodilator with a short half-life, is often used for hypertensive crisis and to deliberately maintain a low blood in certain clinical conditions. Cyanide toxicity is a known complication of sodium nitroprusside use. Herein is reported a case of probable cyanide toxicity in an elderly trauma patient. The pharmacology of sodium nitroprusside and the pitfalls of making the diagnosis of cyanide toxicity are discussed.