After a sudden accidental injury, a person may be pale and unable to speak for a while because of severe pain, or “fainting” and confusion due to head trauma, people often mix these manifestations with the real shock after trauma, and collectively called “shock The “fainting” and confusion that occurs after trauma are often confused with the real post-traumatic shock and are collectively called “shock”. In fact, the shock that occurs after trauma is usually a large wound, constantly bleeding outward, or trauma involving multiple parts, although the surface can not see the bleeding, but there is internal bleeding, the injured person often pale, the ends of the limbs are cold, sweating, can not feel the pulse beat or the pulse is fine to feel, if there are conditions to measure blood pressure, can be significantly lower than the normal range, this situation is different from the previously mentioned, is It is called traumatic shock. When a person suffers a traumatic injury, especially a serious one, shock is often caused by blood loss and can be life-threatening. Therefore, the prevention or resuscitation of shock after trauma is often the first consideration. So why does trauma cause shock? To figure out the reason, first we need to know what shock is all about. Shock is a very complex systemic reaction, is the body in the case of a sharp reduction in effective circulating blood volume, due to organs (such as the heart, lungs, liver, kidneys) and tissue blood perfusion caused by insufficient metabolic disorders and cell damage pathological process. There are many causes of shock, but all have a common feature, namely, a sharp decrease in effective circulating blood volume. By effective circulating blood volume, we mean the amount of blood circulating through the cardiovascular system per unit of time. Shock is followed by microcirculatory disturbances, changes in fluid metabolism, and secondary damage to vital internal organs, which can be life-threatening in a short period of time in severe cases. Shock caused by trauma is hypovolemic shock, that is, it is caused by a severe shortage of blood supply to life-sustaining blood vessels and a sharp decrease in blood volume. After trauma, especially in some patients who have suffered serious injuries, such as fractures, crush injuries, rupture of large blood vessels, rupture of internal organs, etc. It leads to a large amount of blood loss or serious internal bleeding, such as thigh bone fracture, even if there is no outside bleeding wound, adults may lose more than 1000 ml of blood (the total blood volume of the human body is about 4000 ml), which also causes a decrease in the effective circulating blood volume. At the same time, due to edema, necrosis or decomposition of the injured tissue, it will further aggravate the circulatory disorder. When the above factors exceed the body’s compensatory limits, shock can be triggered, and if timely treatment is not obtained, circulatory failure and death may occur. Therefore, when a patient suffers a more serious trauma, he or she should be sent to the hospital immediately for treatment, so as to effectively prevent post-traumatic shock or to be able to save in time.