Free BCEN Certified Emergency Nurse (CEN) Practice Question

While all options presented could be considered in cyanide poisoning management, hyperbaric oxygen therapy is the BEST next step after hydroxocobalamin administration. Here's why:

1. Hyperbaric oxygen therapy can help overcome cyanide-induced cellular hypoxia by increasing dissolved oxygen in the plasma, bypassing the blocked mitochondrial cytochrome oxidase.

2. It aids in displacing cyanide from cytochrome oxidase, facilitating its elimination.

3. It can be particularly beneficial for smoke inhalation victims who may have concurrent carbon monoxide poisoning.

Sodium thiosulfate, while useful, is typically given after hydroxocobalamin and wouldn't be the immediate next step. Hemodialysis isn't typically necessary unless there's severe acidosis or renal failure. Methylene blue is not indicated for cyanide poisoning; it's used for methemoglobinemia.

This question tests the candidate's ability to prioritize treatments and understand the synergistic effects of different therapies in complex toxicological emergencies.