ON AN ACCIDENT BY LIQUID-NITROGEN - HISTOLOGICAL-CHANGES OF SKIN IN COLD

Two young researchers were found lying beside 3 Dewar flasks for liqui d nitrogen in a cold experimental room of a university. They were sent to a hospital but died 1.5 h after cardiopulmonary resuscitation. One of the cadavers had dark red discoloration of the skin on the left ar m at autopsy. By the histological investigation of the discolored regi on karyopyknosis and vacuolation of the keratinocytes were noticeably observed in the epidermis. In addition, hyperemia and edematous change s were seen. Hemoglobin (Hb) was not immunodetected in the skin tissue except intravascular erythrocytes. Therefore, these histological find ings of the discolored skin can indicate that the skin damage was prod uced by cold due to liquid nitrogen before death. The cause of death w as asphyxia due to oxygen deficiency. There were few autopsy findings which showed the participation of liquid nitrogen in the accident. But , the histological findings of the discolored region demonstrate that liquid nitrogen was involved in this accident.