Severe heat stroke includes three types of heat stroke: pyrexia, heat cramps, and heat exhaustion. In severe heat stroke, the patient can present with either one of these types or a mixture of these three types. When severe heatstroke occurs, the patient with heatstroke should be moved to a cool place immediately while calling emergency services. Before the arrival of emergency personnel, you can use cold wet towels or ice packs to cool the patient. 1, heat stroke: working in a high temperature and high humidity environment for several hours is prone to heat stroke, and severe cases can occur heat stroke, which is very dangerous and has a very high mortality rate. After the occurrence of pyrexia, early general weakness, dizziness, headache, nausea, reduced sweating and other symptoms, followed by a rapid rise in body temperature, drowsiness, delirium, coma and other conditions. The skin may show dryness, burning, and no sweating. When the peripheral circulation fails, the patient’s pulse accelerates and blood pressure drops, which may be complicated by various cardiac arrhythmias, breathing becomes shallow and fast, rhythm loses normal, and muscles of the limbs may twitch and spasm; 2. Heat cramps: they often occur after strong physical labor in a hot environment, due to excessive sweating, obvious thirst, and large amounts of water, but without adequate salt supplementation, resulting in The concentration of sodium chloride in the blood drops significantly, which can cause paroxysmal, tonic spasms in the muscles of the limbs, mostly in the bilateral gastrocnemius spasms of the lower limbs, accompanied by muscle pain, abdominal cramps and hiccups, but the body temperature is mostly normal; 3, heat exhaustion: mostly seen in the elderly and maternity, as well as in people who are not well adapted to high temperature and high humidity climate and environment in a short period of time, mostly with symptoms such as dizziness, headache, nausea, etc., first. Then there is obvious thirst, chest tightness, pale face, cold sweat, blood pressure will gradually drop, there may also be a transient loss of consciousness, hand and foot convulsions, and in severe cases, there will be peripheral circulation failure.