What is hydrogen cyanide poisoning?

CN , colorless gas with almond bitter odor. difficult to confirm post-burn since non-specific and can't be measured timely, tx is considered for every pt with smoke inhalation, risk of loss of conscious, cardiac arrest, decompensation. Tx: secure airway, no mouth to mouth resusication, single dose of activated charcoal (50g adults, 1g/kg child), treat symptoms, antidote (hydroxycobalamine (70mg/kg) if not available give nitrite