Which cold-related disorder involves freezing of skin and tissue at 30 F or below, commonly affecting the extremities?

Which cold-related disorder involves freezing of skin and tissue at 30 F or below, commonly affecting the extremities?

• A. Frostbite
• B. Frostnip
• C. Trench Foot
• D. Chilblain

Answer: (A)

Frostbite is being tested here. It refers to actual freezing of skin and underlying tissue when exposed to temperatures at or below freezing—about 30 °F (−1 °C) or lower. Ice crystals form in cells and interstitial fluid, causing direct cellular damage and, as thawing occurs, disruption of blood flow, which can lead to tissue death if severe. This is why the extremities are most commonly affected: fingers, toes, ears, and the nose are farthest from the body’s core warmth and often experience prolonged exposure. Understanding the other conditions helps differentiate them. Frostnip involves only the surface of the skin freezing without tissue freezing, so it’s reversible with simple warming. Trench foot results from prolonged exposure to cold, damp conditions and causes ischemic injury without the tissue actually freezing. Chilblains arise from nonfreezing cold exposure and present as inflammatory lesions rather than frozen tissue. If frostbite is suspected, the area should be warmed gradually in warm (not hot) water, around 98–104°F (37–40°C), without rubbing, and medical care should be sought for deeper frostbite or if blisters form.

Frostbite is being tested here. It refers to actual freezing of skin and underlying tissue when exposed to temperatures at or below freezing—about 30 °F (−1 °C) or lower. Ice crystals form in cells and interstitial fluid, causing direct cellular damage and, as thawing occurs, disruption of blood flow, which can lead to tissue death if severe. This is why the extremities are most commonly affected: fingers, toes, ears, and the nose are farthest from the body’s core warmth and often experience prolonged exposure.

Understanding the other conditions helps differentiate them. Frostnip involves only the surface of the skin freezing without tissue freezing, so it’s reversible with simple warming. Trench foot results from prolonged exposure to cold, damp conditions and causes ischemic injury without the tissue actually freezing. Chilblains arise from nonfreezing cold exposure and present as inflammatory lesions rather than frozen tissue.

If frostbite is suspected, the area should be warmed gradually in warm (not hot) water, around 98–104°F (37–40°C), without rubbing, and medical care should be sought for deeper frostbite or if blisters form.