Post: Fang zhouzi: Why are we suffering from "heatstroke "?

◇ (Www.xys.org) (xys5.dxiong.com) (www.xinyusi.info) (xys2.dropin.org) ◇ why are we suffering from "heatstroke "? · Fang zhouzi-we are a constant temperature animal and must maintain the temperature at around 37 degrees Celsius. To maintain the body temperature, the body must continuously generate heat. In a quiet state, body heat is mainly generated during the metabolic process. Body heat is mainly produced by muscle movement when you exercise or perform physical labor. There is a temperature control center in the lower part of the brain, which monitors the temperature changes at all times and sends commands to increase or decrease the temperature to keep the temperature constant. For example, when the weather is cold and the body temperature is insufficient to maintain the body temperature, the lower part of the Hill will command the muscles to exercise involuntarily to supplement the fever, that is, chills. The body's heat is constantly emitted through the skin (breath can also take away part of the heat ). The transfer of heat is transferred from the high temperature zone to the low temperature zone. There are three methods: radiation, convection and transmission. Temperature in the environment than skin temperature (32 ~ 35 degrees Celsius) when it is much lower, the body heat quickly passes through the heat transfer, mainly through the heat radiation, a small part through the heat convection (depending on the air flow rate ), there is also a little bit of heat conduction through direct contact with the air. However, if the body heat is generated in large quantities (for example, during strenuous exercise), or the ambient temperature is close to the skin temperature, the body heat should be emitted as soon as possible. At this time, the temperature control center will send a cooling command to let the skin vascular expand, increase the blood flow flowing through the skin, and take away the body heat through the blood. However, heat transfer alone is not enough, so the temperature control center will also command the skin to sweat, and the heat will be taken away by the evaporation of sweat. When the ambient temperature exceeds the skin temperature, heat transfer is impossible and evaporation becomes the only heat dissipation method. Sweating is a very efficient heat dissipation method. Each evaporation of 1 gram of water can take away 2.43 kilo-focal heat. But it will not evaporate immediately after sweat flow. Whether it can evaporate effectively depends on the humidity of the surrounding air. When the relative humidity is greater than 75%, it is impossible to evaporate effectively. At this time, if the surrounding temperature is very high, the body heat will not be able to effectively emit out, the body heat dissipation mechanism began to speed up, and strive to let out the heat: Breathing becomes fast, the heart quickly beat, sweating heavily. People will feel uncomfortable and have dizziness, headaches, weakness, muscle cramps, nausea, vomiting and other symptoms. It is known as heat failure in medicine. If there is no treatment for heat failure, there may be more serious consequences: there is an obstacle in temperature control, instead of sweating, the skin becomes dry, and the body heat accumulates sharply in the body. On average, the body accumulates 3.49 kilojoules of calories per kilogram, which is enough to increase the body temperature by 1 degree Celsius. That is to say, if a person weighing 70 kilograms evaporate 100 grams of sweat, the temperature can be increased by 1 degree Celsius. In this case, the temperature can exceed 41 degrees Celsius in just ten minutes, and there is a mental disorder, blurred consciousness or coma, which is known as heat-shooting in medicine. If the treatment is not timely, the internal organs will be damaged or even die. Heat failure, heat-shooting and other heat-related diseases are commonly referred to as fever, also known as "heatstroke ". Mild heatstroke (heat failure) as long as you go to a shaded and ventilated place (preferably air-conditioned), take off your clothes and take a rest, drink a non-alcoholic cold drink, and soon you will be able to recover to normal, there is no need to take medicine and no valid over-the-counter drugs are available. At this time, if you take some Chinese patent medicine or some kind of folk therapy (such as scraping), you will also feel very effective, but it is actually self-recovered by the body, and these drugs and treatments are not really effective. The so-called scraping is to use external force to make the subcutaneous capillary rupture, congestion, "Sha points" is the subcutaneous congestion, not the discharge of drugs. Heatstroke has nothing to do with toxin. If there is a heat-shooting problem, you cannot take it lightly. While calling an ambulance, you can transfer the patient to a shady place and take immediate measures to reduce the temperature, for example, soaking the patient with cold water, rinse the patient with a tap, or wipe the patient with a sponge or towel dipped in the cold water. However, the water temperature cannot be too cold, so do not let the patient tremble, it increases the generation of body heat. This is an effective method recommended and implemented by the medical community to treat fever. It is widely used abroad, but it is terrible for many Chinese people. According to the Chinese saying, when the body is hot or sweaty (whether due to heatstroke or intense exercise), it is said that this will cause harm to the body, even dead. Some people explain that when the pores on the skin are opened during fever and sweating, the cold water will enter the body from the pores. This is ridiculous. The human skin is not a sieve, and water cannot enter the body through pores. When the skin is not damaged, water cannot penetrate into the body through the skin, otherwise it is equivalent to drinking water to quench thirst. Some people say that when heatstroke occurs, taking a cold bath will shrink pores and sweat will not flow out, but the heat will not go out. This is also absurd. The reason why sweat can dissipate heat is the evaporation of water, and once soaked in water, sweat can not evaporate, sweat does not play the role of heat dissipation, sweat can flow out does not matter. When people are in water, they heat dissipation mainly through heat conduction in direct contact between skin and water. In hot weather, take some measures to prevent heatstroke, such as drinking more water (do not wait for thirst to drink again), exercise less, wear less clothes, avoid direct sunlight, and apply sunscreen to activities in the sun. When the surrounding temperature is close to the body temperature, the fan cannot prevent heatstroke. The best way to prevent heatstroke is to use air conditioners. If you are worried that you will not be able to enable air conditioners during the "cold" day, you will be at risk of heatstroke, especially for the elderly and children. 2011.5.30 (China Youth Daily, 6.1 1.6.1.) (xys20110602) ◇ (www.xys.org) (xys5.dxiong.com) (www.xinyusi.info) (xys2.dropin.org) ◇