Cyanide toxicity

Case: 42 years old male is brought to ED with suspected cyanide poisoning after ingesting a large amount of apricot. While putting Central Venous Catheter (CVC), blood is expected to be? (select one)

A) dark purple

B) bright red

Answer: B

This question's objective is to look for clues in cyanide poisoning. Pertinent history plays an important role. On physical exam, patient may appear flushed with "cherry red" color. Labs may show a high anion gap and elevated lactic acid. Arterial and venous blood gas (ABG and VBG) may have a narrowed venous-arterial PO2 gradient, and venous blood may appear bright red. Hydroxocobalamin is the preferred antidote.

#toxicity

References:

1. Hall AH, Rumack BH. Clinical toxicology of cyanide. Ann Emerg Med 1986; 15:1067.

2. Gracia R, Shepherd G. Cyanide poisoning and its treatment. Pharmacotherapy. 2004 Oct;24(10):1358-65. doi: 10.1592/phco.24.14.1358.43149. PMID: 15628833.