Abstract
Poisoning with potassium cyanide is usually fatal because of the inhibition of cytochrome oxidase in tissue. It is known that patients exposed to a large-dose die after several minutes. We report a survival case of acute potassium cyanide poisoning likely due to a delayed severe symptomatic episode. A male in his 30’s took three capsules containing potassium cyanide. After approximately 15 minutes from the time of ingestion, the subject exhibited dilated pupils and tachycardia. Upon admission (approximately 38 minutes after ingestion), the subject began to show signs of tachypnea. More severe symptoms, such as circulatory failure, cyanosis and severe metabolic acidosis, appeared approximately 86 minutes after ingestion. We administered antidotes and observed that, the severe metabolic acidosis and circulatory failure improved rapidly. The whole blood cyanide concentration peaked at 3.1 μg/ml, and then gradually decreased. The patient was discharged after 10 days without any sequelae. The delayed development of symptoms is likely due to the slow digestion of the capsules. Therefore, it is imperative to determine, not only the name and quantity of an ingested poison, but also the form in which the poison was ingested. This information can aid in the prediction of symptomatic episode development and treatment.
