[Influence of inhaling carbon monoxide-containing gas in fire fatalities--an investigation of forensic autopsy cases].

To investigate the influence of inhaling carbon monoxide (CO)-containing gases in fires, forensic autopsy cases of fire victims (n=193) were examined in comparison with control cases involving other causes of fatal CO intoxication (n=6 :COHb, 69.5-83.0%). Fire victims with blood carboxyhemoglobin (COHb) levels over 60% (n=76) showed a larger arterio-venous difference in blood COHb level compared with other fire victims and other fatal CO intoxication. However, biochemical findings for myocardial, cerebral damage or respiratory distress were milder in most cases, independent of blood cyanide levels, being similar to those in fatality due to inhalation of blast furnace gas with an extremely high concentration of CO (ca. 40%). These observations suggest that an acutely fatal factor in fires involves inhalation of gases containing high amounts of CO, which may induce peracute circulatory collapse before causing marked myocardial and cerebral damage or respiratory distress.