Which condition requires rapid cooling and rehydration in the field?

• A. Heat stroke
• B. Heat exhaustion
• C. Hypothermia
• D. Dehydration

Answer: (A)

Heat stroke demands rapid cooling and rehydration in the field because the body's core temperature climbs to dangerous levels and the brain and other organs can begin to fail quickly. The priority is to lower core temperature as fast as possible to prevent permanent damage, while also restoring circulating volume to support perfusion. In practice, move the person to shade, remove excess clothing, and apply aggressive cooling—evaporative cooling (spray with water and fan) or ice-water immersion if feasible and safe—to push core temperature toward the 38–39°C (100–102°F) range. Simultaneously, treat dehydration: if the person can drink, offer cold fluids; if not, establish IV access and give isotonic fluids per protocol while monitoring vital signs. Continue cooling and rehydration and arrange for rapid evacuation because heat stroke can deteriorate rapidly and be fatal if not managed promptly.

Heat exhaustion differs because it involves heat stress and dehydration without central nervous system dysfunction, so cooling is less urgent and rehydration is the main treatment. Hypothermia requires warming, not cooling, and dehydration alone involves rehydration without extreme hyperthermia.