Prevalence of hydrogen cyanide and carboxyhaemoglobin in victims of smoke inhalation during enclosed-space fires: a combined toxicological risk.Clin Toxicol (Phila). 2012 Sep; 50(8):759-63.CT
Hydrogen cyanide (HCN) is one of the most toxic components of fire smoke, but insufficient attention is paid to its potential role as a cause of injury or death in victims (alive or dead) of enclosed-space fires.
To analyse the prevalence of toxic HCN exposure in fire victims and factors that may influence its toxicity, particularly the co-presence of carbon monoxide (CO) and ethanol.
MATERIALS AND METHODS
Blood samples from fire victims and persons rescued from fires were analysed.
A positive result for HCN (mean concentration 16.83 mg/l) was detected in blood samples from 169 of 285 fire-related deaths (59%). Ethanol was present in 91 (65%) of 139 samples with coincident presence of HCN and carboxyhaemoglobin (COHb). HCN (mean 4.0 mg/l) was also detected in 20 of 40 (50%) fire survivors.
The high prevalence of coincident CO and HCN in enclosed-space, fire-related deaths should alert clinicians to suspect toxic HCN exposure in all persons rescued from fire with signs and symptoms of respiratory distress.
Medical procedures in persons rescued from enclosed-space fires, especially in the pre-hospital setting, should be augmented to cover the possibility of toxic HCN exposure, particularly in individuals who do not respond to standard supportive therapy. Likewise, post-mortem investigations should routinely include assays for HCN when determining probable cause of death.