Lethal Hypothermia

Summary

Hypothermia is a relatively rare cause of death in temperate climate zones. In most cases of lethal hypothermia, elderly and mentally ill persons are affected as well as persons under the influence of alcohol or other substances. Although most cases of death from hypothermia are accidental, they, more often than other types of death from environmental conditions, produce a death scene that is at first obscure and difficult to interpret. The reason for this frequent obscurity is mainly because of the phenomenon of the so-called paradoxical undressing as well as the hide-and-die syndrome. In many cases, the bodies are found partly or completely unclothed and abrasions and hematomas are found on the knees, elbows, feet, and hands. The reason for the paradoxical undressing is not yet clearly understood. There are two main theories discussed: one theory proposes that the reflex vasoconstriction, which happens in the first stage of hypothermia, leads to paralysis of the vasomotor center thus giving rise to the sensation that the body temperature is higher than it really is, and, in a paradoxical reaction, the person undresses. The other theory says that it seems to be the effect of a cold-induced paralysis of the nerves in the vessel walls that leads to a vasodilatation giving an absurd feeling of heat. In 20% of cases of lethal hypothermia, the phenomenon of the so-called hideand-die syndrome also can be observed. Some of these bodies are situated in a kind of “hidden position,” for example, located under a bed or behind a wardrobe. Apparently, this finding is the result of a terminal primitive reaction pattern, which is probably an autonomous behavior triggered and controlled by the brain stem. It shows the characteristics of both an instinctive behavior and a congenital reflex.