Final answer:
For severe frostbite treatment, rewarming the head and torso is the priority to protect the body's core temperature and vital organs.
Step-by-step explanation:
When treating a child with severe frostbite, it is vital to prioritize rewarming the head and torso before the extremities like hands and feet.
According to medical protocols, the primary objective is to prevent further heat loss and to protect the body's core temperature. The body instinctively reduces blood circulation to the extremities to conserve heat for the vital organs located in the head and torso.
Therefore, warming the head and torso first is crucial to address the potential hypothermia condition that could be life-threatening.