Prolonged exposure of the feet to cold but not freezing water for prolonged periods can result in immersion foot. This was particularly common on the Western Front during World War I, when it was termed "trench foot."
Settings:
(1) prolonged exposure of the feet to cold water
(2) lack of footwear, or improper footwear for conditions
(3) repeated trauma to the feet or prolonged standing
Clinical findings: one or more of the following:
(1) numbness
(2) erythema
(3) blistering
(4) swelling
(5) painful paresthesias
(6) leg cramping
(7) muscle weakness or atrophy
(8) ulceration
(9) cellulitis
(10) gangrene
Three clinical states are recognized:
(1) ischemia: vasoconstriction resulting in the distal extremity being pale and pulseless
(2) hyperemia: vasodilatation with increased circulation, resulting in red, swollen and painful feet with a bounding pulse
(3) posthyperemic
Therapy:
(1) Mild forms may respond to cleaning, rest and elevation of the feet.
(2) Ischemic: Rewarming needs to be done carefully, since overheating of tissue may result in tissue infarction and gangrene.
(3) Hyperemic: Careful cooling is required to reduce the increased circulation.
