Cyanide poisoning is a possible cause of cardiac arrest among fire victims, and empiric antidote treatment may improve outcomes

Carbon monoxide and cyanide poisoning are important causes of death due to fire. Carbon monoxide is more regularly assessed than cyanide at the site of burn or smoke inhalation treatment due to its ease in assessment and simplicity to treat. Although several forensic studies have demonstrated the significance of cyanide poisoning in fire victims using blood cyanide levels, the association between the cause of cardiac arrest and the concentration of cyanide among fire victims has not been sufficiently investigated. This study aimed to investigate the frequency of cyanide-induced cardiac arrest in fire victims and to assess the necessity of early empiric treatment for cyanide poisoning. This study was a retrospective analysis of fire victims with cardiac arrest at the scene who were transported to a trauma and critical care center, Kyorin University Hospital, from January 2014 to June 2017. Patients whose concentration of cyanide was measured were included. Five patients were included in the study; all died despite cardiopulmonary resuscitation. Three of these victims were later found to have lethal cyanide levels (>3 μg/ml). Two of the patients had non-lethal carboxyhemoglobin levels under 50% and might have been saved if hydroxocobalamin had been administered during resuscitation. According to our results, cyanide-induced cardiac arrest may be more frequently present among fire victims than previously believed, and early empiric treatment with hydroxocobalamin may improve outcomes for these victims in cases where cardiac arrest is of short duration.