LESSON 4
INJURIES DUE TO ENVIRONMENTAL EXTREMES
Section I. ENVIRONMENTAL COLD INJURIES
4-1.
INTRODUCTION
a. Definition-Cold Injury. Cold injury is defined as tissue trauma produced by
exposure to cold. The type of injury produced depends upon the degree of cold to
which the body (or its parts) is exposed, the duration of exposure, and certain
environmental factors.
(1) Chilblain. Chilblain is a swelling and reddening of the skin that usually
results from intermittent exposure to temperatures above freezing accompanied by high
humidity. Although chilblain itself is not a dangerous cold injury, it can result in open
sores (lesions), which can become infected and can lead to more dangerous cold
injuries.
(2) Immersion syndrome. Trench foot and immersion foot, result from
prolonged exposure to wet, cold footgear or outright immersion of the feet at
temperatures usually below 50 F.
There is no major difference between trench foot and immersion foot
with respect to management or to the conditions that cause the injury.
Both result from prolonged exposure of the feet to wet cold:
-- Trench foot to cold, wet socks and boots.
-- Immersion foot to cold water.
Both occur with or without socks and boots.
The term "immersion syndrome" is often employed to cover
immersion foot, trench foot, and similar cold injuries.
At the upper range of temperatures, exposure of 12 hours or more
will cause injury.
Shorter durations at or near 32 F will cause the same injury.
Immersion syndrome is usually associated with standing in place for
significant amount of time.
MD0152
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