Heat stroke is an emergency, and can be fatal.

Heat stroke is the human thermoregulatory dysfunction resulting from high temperatures; the accumulated excessive body heat cannot be effectively distributed, causing nerve damage.  Heat stroke is a medical emergency.  Severe heat stroke can be fatal, and has a high mortality rate. 

A person’s normal body temperature is usually 37 degrees.  If it exceeds this temperature, the body has to rely on blood circulation to transmit the excessive heat to the surface, and then dissipate it from the surface by a variety of ways in order to maintain the balance of body temperature.  In practice, there are the several situations that usually impact this balance.