Cyanide is a rapidly acting and deadly chemical. Smelling of bitter almonds or entirely odorless, cyanide may take the form of a colorless gas, a liquid, or a crystal powder. Cyanide, like carbon monoxide (CO), binds to hemoglobin in red blood cells and blocks their capacity to carry oxygen to cells and tissues.
Inhaling even small amounts of fire smoke can be fatal. Serious neurological effects may be delayed days or weeks after acute poisoning. Chronic exposure may cause persistent headaches, dizziness, nausea, and permanent neurological damage. Smoke inhalation may be further complicated by airborne particles and by burns to the throat and lungs.
Hyperbaric oxygen therapy (HBOT) is indicated for the emergency treatment of carbon monoxide poisoning complicated by cyanide poisoning after smoke inhalation. Hyperbaric oxygen is also an adjunctive therapy for pure cyanide poisoning in patients who do not respond to cyanide antidotes.
HBOT dissolves additional oxygen in the blood plasma and has been shown to work effectively alone and in combination with hydroxocobalamin (Cyanokit) and other cyanide antidote kits.