Abstract
Objective: This study was conducted following the first surveillance in 2006, in order to investigate the characteristics of patients suffering from heatstroke who were treated at either emergency medical centers or emergency departments in Japan.
Methods: The patient' background information was collected and thereafter their medical data were recorded by the responsible medical staff according to the newly prearranged format and then were analyzed by the heatstroke surveillance committee members of the Japanese Association for Acute Medicine (JAAM).
Results: Nine hundred and thirteen patients suffering from heatstroke were treated at 82 hospitals from June to September in 2008. The patients' mean age was 44.6 years, and their severity of heatstroke was categorized as Class I (mild, no need for specific treatment), Class II (moderate, requiring hospitalization for observation) and Class III (severe, requiring intensive care), consisting of 52%, 24% and 24% of patients, respectively. The classical heatstroke group comprised patients older than the exertional heatstroke group. All patients demonstrated their worst condition on the first or the second day of hospitalization, except for those who died. For 13 deaths of 15 Class III fatal cases, the cause of death was multiple organ failure occurred within 4 days of hospitalization. Disturbance of consciousness (2 to300 according to the Japan Coma Scale), shock status (with a systolic arterial pressure of 90mmHg or less), higher body temperature (39°C or higher) and tachycardia (120/BPM or more) have been found to demonstrate significant risk factors requiring hospitalization for advanced treatment. In particular, preexisting status of being confined to bed and/or being unable to care for oneself were found to be associated with classical heatstroke in the elderly people.
Conclusion: In order to reduce morbidity and mortality of multiple organ failure secondary to heatstroke, it is important to identify the early signs and symptoms suggesting the possible onset of heatstroke and to provide first aid treatment as soon as possible.
