Forensic Pathology for Police - Brainshare Public Online Library

Chapter 18
Temperature-Related Deaths
When the sun rose, God provided a scorching east wind, and the
sun blazed on Jonah’s head so that he grew faint. He wanted to
die, and said, ‘It would be better for me to die than to live.’
Jonah 4:8
Abstract Chapter 18 begins by providing a general description of the normal
temperature-regulation mechanisms in humans, along with an introduction to the
concepts of hyperthermia and hypothermia. The remainder of the chapter is devoted
to relatively in-depth examination of hypothermia and hyperthermia, with emphasis
on scene investigation, autopsy findings, and death certification issues.
Keywords Temperature · Hypothermia · Hyperthermia
Introduction
The normal human body temperature is between 37.0 and 37.6 ◦ C (98.6–99.7 ◦ F),
with temperatures up to 38.6 ◦ C (101.5 ◦ F) considered normal in infants and the
elderly. There are slight daily cyclical variations, with the lowest temperatures
occurring in the early morning and the highest in the afternoon. Vigorous exercise
may cause a several-degree increase in temperature. The body temperature is
under the control of feedback neural mechanisms involving the brainstem and the
hypothalamus. Human tissue can survive only within a range of tissue temperatures
between 20 and 44 ◦ C (68 and 111 ◦ F).
Ultimately, body temperature depends on a balance between “heat load” and
“heat loss.” A body’s heat load represents the heat produced by normal metabolism
plus any heat gained from the environment. Heat loss occurs via four mechanisms,
each of which involves the transfer of heat from warmer objects to cooler objects.
The four mechanisms of heat loss are “conduction,” “radiation,” “evaporation,” and
“convection.” Conduction represents the direct transfer of heat from one object to an
adjacent object. Radiation is heat loss via the emission of infrared rays. Evaporation
J. Prahlow, Forensic Pathology for Police, Death Investigators, Attorneys,
and Forensic Scientists, DOI 10.1007/978-1-59745-404-9_18,
C○ Springer Science+Business Media, LLC 2010
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