A 32-year-old worker is brought by ambulance from a silver recovery plant complaining of weakness and dizziness after being overcome by fumes from the recovery tanks. Shortly after arrival, he becomes unconscious. You are concerned about toxic exposure, so you remove the patient's clothing, intubate him, and administer 100% oxygen and:
Crush a pearl of amyl nitrite and hold it in the intake valve of the Ambu bag.
Administer methylene blue.
Begin chelation therapy.
Consult nephrology for possible hemodialysis.
Cyanide poisoning must be treated if suspected. Burning polyurethane or nylon, electroplating and silver recovery plants, and pest fumigation are some of the most common sources. Detecting the presence of a bitter almond odor is helpful, but 40% of the population cannot smell this. Initial treatment is to remove contaminated clothing and begin 100% oxygen. Amyl nitrite is used initially, followed by sodium nitrite. Both of these agents form methemoglobin, which acts to remove cyanide from the cytochrome oxidase system and form cyanomethemoglobin. Thiosulfate complexes form thiocyanate, which is excreted in the urine. Laboratory tests are obtained after treatment is started. Sodium nitrite may cause hypotension, which should be treated with fluid and pressors as needed.