Found the "Heatstroke" section under "ABNORMALITIES OF BODY TEMPERATURE REGULATION" in block9. Let me read the full section text.

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Definition/Cause: Heat stroke occurs when body temperature rises beyond a critical level (105°F-108°F). It develops when environmental heat load exceeds the body's capacity for heat loss - especially in hot, humid conditions where evaporative cooling (sweating) becomes ineffective. The critical environmental temperature is lower during heavy physical work (as low as 85°F-90°F) and when air is fully humidified or the body is immersed in water (above ~94°F).

Clinical Features (Symptoms): Dizziness, abdominal distress (often with vomiting), delirium, and eventually loss of consciousness if body temperature is not promptly reduced. These features are often worsened by circulatory shock resulting from excessive loss of fluid and electrolytes in sweat. Once the temperature rises to a critical level, the condition becomes self-perpetuating because the elevated temperature itself increases cellular metabolic rate, which further raises heat production - a vicious cycle called "vicious cycle of heatstroke."

Harmful Effects/Pathology: Hyperpyrexia is highly damaging to body tissues, particularly the brain - even a few minutes of very high temperature can be fatal. Pathological findings include local hemorrhages and parenchymatous degeneration of cells throughout the body, especially in the brain (neurons, once destroyed, cannot be replaced). Damage to the liver, kidneys, and other organs may be severe enough to cause organ failure and death, sometimes days after the episode.

Treatment: Immediate reduction of body temperature is essential - total immersion of the body in cold water is an effective method. Since cold-water immersion often induces uncontrollable shivering (which increases heat production), a muscle relaxant may be given. Sponge/spray cooling of the skin combined with blowing cool air over the moist skin has also been suggested as a more practical alternative for rapid core cooling.