What is cold shock?
Cold shock is the body's response to sudden cold. It is commonly the result of falling or jumping into cold water. The cold shock response is short, which can only last a few minutes. However, it can be very dangerous, since the sudden cold constricts blood vessels in the skin, making blood rush back to your heart and increasing your blood pressure. It also makes breathing difficult and induces hyperventilation and a gasp response. In cold water, this uncontrolled gasping may cause water to enter your airways, increasing your chances of drowning.