How does acute cold exposure alter cutaneous blood flow and skin warming?

• A. Rapid cutaneous vasoconstriction to limit heat loss, with occasional episodic vasodilation in some areas to reduce tissue damage.
• B. Chronic vasodilation increases heat loss.
• C. No change in cutaneous blood flow.
• D. Persistent vasoconstriction with no episodic vasodilation.

Answer: (A)

Acute cold exposure triggers the body to conserve heat by rapidly constricting the skin’s blood vessels. This vasoconstriction reduces blood flow to the skin, limiting radiant and convective heat loss and helping keep core temperature from dropping quickly. At the same time, in some distal areas like fingers and toes, there can be episodic bouts of vasodilation known as cold-induced vasodilation or the Hunting response. These brief increases in blood flow momentarily warm the tissue to prevent damage from freezing, even though the overall skin perfusion remains reduced. So the dominant response is rapid vasoconstriction to limit heat loss, with occasional episodic vasodilation in certain areas to protect tissues.