Surviving cyanide poisoning: A case report highlighting the role of early antidote use

Survival after high-dose oral cyanide ingestion is rare, and when untreated cases often result in death within an hour. Immediate treatment however, can be lifesaving. We describe a patient who fully recovered after prompt intervention. He arrived at the emergency department unconscious, with red skin and a Glasgow Coma Scale of 3 and was suspected of an intentional intoxication with an unknown white crystalline powder. He rapidly suffered a cardiac arrest. Blood gas analysis showed severe metabolic acidosis, high lactate, and slightly elevated methemoglobin. In suspect of cyanide poisoning, hydroxocobalamin (2 doses of 5 g intravenous) and sodium thiosulfate (12.5 g intravenous) were administered. Thereafter spontaneous circulation returned. The patient was intubated and sedated in the intensive care unit for four days. After extubation, he was transferred to a general ward. A magnetic resonance imaging scan showed no post-anoxic or toxic damage. During his 14-day stay, he fully recovered. The white powder was identified in the pharmaceutical laboratory by infrared spectrometry, confirming the presence of cyanide. Subsequently, the patient admitted to ingesting potassium cyanide. He obtained the potassium cyanide from his workplace, a chemical laboratory.