Frostbite
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Basics
Description
- Tissue damage caused by cold temperature exposure
- Mechanism:
- Tissue damage results from:
- Direct cell damage: Intracellular ice crystal formation
- Indirect cell damage: Extracellular ice crystal formation leads to intracellular dehydration and enzymatic disruption
- Reperfusion injury: Occurs upon rewarming. Fluid rich in inflammatory mediators (prostaglandin and thromboxane) extravasates through damaged endothelium promoting vasoconstriction and platelet aggregation
- Clear blisters from extracellular exudation of fluid
- Hemorrhagic blisters occur when deeper subdermal vessels are disrupted, indicating more severe tissue injury
- The end result is arterial thrombosis, ischemia, and ultimately, necrosis
- Devitalized tissue demarcates as the injury evolves over weeks to months, hence the phrase “frostbite in January, amputate in July”
- Tissue damage results from:
Etiology
- Cold exposure: Duration of exposure, wind chill, humidity, and wet skin and clothing all increase the likelihood of frostbite
- Predisposing factors:
- Extremes of age
- Altered mental status (intoxication or psychiatric illness)
- Poor circulatory status
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Basics
Description
- Tissue damage caused by cold temperature exposure
- Mechanism:
- Tissue damage results from:
- Direct cell damage: Intracellular ice crystal formation
- Indirect cell damage: Extracellular ice crystal formation leads to intracellular dehydration and enzymatic disruption
- Reperfusion injury: Occurs upon rewarming. Fluid rich in inflammatory mediators (prostaglandin and thromboxane) extravasates through damaged endothelium promoting vasoconstriction and platelet aggregation
- Clear blisters from extracellular exudation of fluid
- Hemorrhagic blisters occur when deeper subdermal vessels are disrupted, indicating more severe tissue injury
- The end result is arterial thrombosis, ischemia, and ultimately, necrosis
- Devitalized tissue demarcates as the injury evolves over weeks to months, hence the phrase “frostbite in January, amputate in July”
- Tissue damage results from:
Etiology
- Cold exposure: Duration of exposure, wind chill, humidity, and wet skin and clothing all increase the likelihood of frostbite
- Predisposing factors:
- Extremes of age
- Altered mental status (intoxication or psychiatric illness)
- Poor circulatory status
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