During Hyperthermia

• Hyperthermia is defined as a temperature greater than 37.5–38.3 °C (100–101 °F),that occurs without a change in the body's temperature set-point.


• Body temperatures above 40 °C (104 °F) can be life-threatening.

During Hypothermia

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  Hypothermia is a condition in which core temperature drops below the required temperature for normal metabolism and body functions which is defined as 35.0 °C (95.0 °F).


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  Blood vessels in the skin constrict due to nerve stimulation from the brain which reduces blood flow to the skin.


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  Radiant heat loss is reduced from the skin.


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  Sweat production decreases.


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  Shivering, an involuntary contraction of skeletal muscles due to nerve stimulation, helps to generate body heat.


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  The lowest documented body temperature from which anyone has recovered was 13.0 °C (55.4 °F), in a drowning incident involving a 7-year-old girl in Sweden in December 2010.