However, they may reach relatively high values in patients who receive nitroprusside for 1 hour or more during surgery and may even exceed those reported in patients with tropical neuropathy due to chronic ingestion of cassava. With an intact pathway, normal amounts of rhodanase in the liver and tissues, normal amounts of endogenous thiosulfate, and normal β-mercaptopyruvate sulfur transferase activity in erythrocytes, serum cyanide concentrations in and red cells remain low. Cyanide and thiocyanate and toxicity can cause metabolic acidosis, tachycardia, tachypnea, vomiting, headache, fatigue, nausea, anorexia, disorientation, and coma, in severe cases death can occur. Thiocyanate is excreted mainly in the urine, with a half-life of about 1 week. The serious toxic effects of nitroprusside result from its being metabolized to cyanogen and cyanide with subsequent detoxification to thiocyanate, although thiocyanate toxicity can also occur. Aronson MA, DPhil, MBChB, FRCP, HonFBPhS, HonFFPM, in Meyler's Side Effects of Drugs, 2016 Cyanide toxicityĮxcessively rapid infusion of nitroprusside causes sweating, nausea, vomiting, anxiety, restlessness, and muscle twitching these symptoms disappear after slowing the rate of infusion. Because it binds with cyanide without forming methemoglobin, hydroxocobalamin can be used to treat patients without compromising the oxygen-carrying capacity of hemoglobin.J.K. Hydroxocobalamin detoxifies cyanide by binding with it to form the renally excreted, non-toxic cyanocobalamin. The key treatment is early administration of 1 of the 2 antidotes currently available in the United States: the well-known cyanide antidote kit and hydroxocobalamin. As poisoning progresses, hemodynamic status may become unstable.

Early respiratory signs include transient rapid and deep respirations. Skin may look normal or slightly ashen, and arterial oxygen saturation may be normal.

As hypoxia progresses, progressively lower levels of consciousness, seizures, and coma can occur. Early manifestations include anxiety, headache, giddiness, inability to focus the eyes, and mydriasis. Signs and symptoms of cyanide poisoning usually occur less than 1 minute after inhalation and within a few minutes after ingestion. Cyanide causes intracellular hypoxia by reversibly binding to mitochondrial cytochrome oxidase a 3.

Cyanide antidote kit