Heat stroke is a disease caused by dysfunction of the body’s thermoregulatory center, failure of sweat glands and excessive loss of water and electrolytes in a high temperature and high humidity environment. Clinical manifestations are high fever, profuse sweating or sweat closure, deficiency, fainting or coma and other central nervous system symptoms. There are three main types of severe heat stroke: heat cramps, heat exhaustion and pyrexia. 1) Heat cramps: after intense exercise and profuse sweating in a hot environment, tonic muscle spasms occur due to severe loss of body sodium, commonly in the muscles of the more active limbs, abdominal and back muscles with muscle spasms and painful contractions, especially in the gastrocnemius muscle, often symmetrical and paroxysmal. 2) Heat exhaustion: is a continuation of heat cramps It is common in the elderly and patients with chronic diseases, mainly due to dehydration, sodium loss, blood concentration and blood volume deficiency caused by massive sweating. The main manifestations are weakness, dizziness, headache, thirst, chest tightness, nausea, vomiting, palpitations, excessive sweating, increased respiration, fine and rapid pulse, cardiac arrhythmia, wet and cold skin, syncope, muscle spasms, decreased blood pressure and even shock, but the damage to the central nervous system is not obvious. 3) Heat exhaustion: due to prolonged heat exhaustion or excessive heat production and decreased heat dissipation, manifested as high fever (rectal temperature ≥ 41℃), dry skin, severe headache, dizziness, nausea, vomiting, burning, delirium, coma, convulsive seizures, shortness of breath, tachycardia, narrow pupils, meningeal irritation signs and other manifestations, and in severe cases, shock, heart failure, cerebral edema, pulmonary edema, acute respiratory distress syndrome, acute renal failure, acute heavy hepatitis, DIC, multi-organ failure or cardiac arrest.