Wilderness and Rescue Medicine 8th Edition

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Wilderness and Rescue Medicine

Chapter 18 Review: Cold Injuries

• The precursor to frostbite is sometimes called frostnip. This occurs with the intense vasoconstriction and loss of local tissue perfusion that results from exposure to subfreezing temperatures. • Superficial frostbite occurs when the water in skin cells begins to freeze. Sensation is dulled, and the area appears white or blue and feels soft to the touch. • Deep frostbite is a serious ischemia to infarction problem. The skin and underlying tissues are frozen solid. The area is white or bluish and hard to the touch. Deep frostbite should be evacuated emergently to a medical facility for controlled rewarming. • Field rewarming of deep frostbite is a high-risk treatment and is carried out only when evacuation is impractical and the equipment and shelter is available. • Rewarmed frostbite should be treated as a high-risk wound and should never be allowed to refreeze. • The prevention of frostbite is an essential survival skill and requires insulation, protection, and a warm body core. • Trench foot is an injury that develops with prolonged exposure to cold and wet conditions above freezing. It is not limited to feet and often involves the hands of paddlers, fishermen, and others working or playing on the water. • Raynaud’s is a disorder of the blood vessels near the skin, most often affecting the hands and fingers and aggravated by cold exposure. Profound vasoconstriction causes temporary ischemia, a white or blue appearance, and numbness and tingling. There is no field treatment, but it is a predisposing factor of frostbite.

Rewarmed superficial frostbite.