Frostbite is a topic covered in the 5-Minute Emergency Consult.

To view the entire topic, please or purchase a subscription.

Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:

Emergency Central

-- The first section of this topic is shown below --



  • 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 form 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.”


  • 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

-- To view the remaining sections of this topic, please or purchase a subscription --