What are the pathophysiological stages and characteristics of burns?

Hello! According to the pathophysiological characteristics of burns, the course of the disease can be roughly divided into three stages, but this is artificial staging, and each stage often overlaps with each other. The purpose of staging is to highlight the key points of clinical treatment in each stage.

(1) Acute exudation stage (shock stage), the immediate reaction after tissue burn is exudation of body fluids, which generally lasts for 36 ~ 48 hours. A small area of shallow burns and limited body fluid leakage will not affect the effective circulating blood volume of the whole body through the compensation of the human body. People with large and deep burns may suddenly go into shock due to exudation of a large amount of body fluids and other hemodynamic changes. The shock in the early stage of burn basically belongs to hypovolemic shock, but different from general acute blood loss, body fluid exudation is gradual, which is the most acute in 2-3 hours after injury, reaching its peak in 8 hours, then gradually slowing down and gradually recovering in 48 hours. The edema fluid oozing between tissues began to recover, and the clinical manifestations were that blood pressure tended to be stable and urine began to increase. According to the above rules, the speed of fluid replacement in the early stage of burn should be fast first and then slow.

(2) Edema in recovery period and infection period of burn. At first, infection rose to be the main contradiction. Shallow burns, such as improper treatment of early wounds, can cause inflammation around the wounds (such as cellulitis). Due to shock, the systemic immune function of severe burns is in a low state, and the susceptibility to pathogens is high, and the probability of early systemic infection is also high, and it is predicted.

After that, it is also the most serious. An important experience in treating burns in China, that is, correcting shock in time, is of anti-infection significance.

The threat of infection will last until the wound heals. Burn is characterized by extensive physiological barrier damage, extensive necrotic tissue and exudation, which is a good culture medium for microorganisms. Heat-induced tissue injury, first coagulative necrosis, then tissue dissolution, 2-3 weeks after injury, tissue dissolution stage is another peak of systemic infection. The granulation tissue at the tissue junction is also gradually formed. If the necrotic tissue can be removed or drained in time, a granulation tissue barrier will be formed in about 2 weeks, which can limit the invasion of pathogenic bacteria. If not handled properly, pathogenic bacteria can invade adjacent unburned tissues. In large-scale invasive infection, the amount of bacteria in tissue often exceeds 105 /g, and the amount of bacteria continues to increase, which can form burn wound sepsis.

The wound surface is dull, decayed and sunken, and necrotic spots appear. Even if bacteria do not invade human blood, early excision or excision is often used to eliminate the wound in time. When the wound is basically repaired, the complications are obvious.

Reduce.

(3) Repair period: After tissue burn, tissue repair has begun at the same time as inflammatory reaction. Most superficial burns can be repaired by themselves, and the depth 1 1 "depends on the fusion of the remaining epithelial islands; 1 1 1 "burns were repaired by skin transplantation.

At present, most of the work of burn necrosis tissue resection and skin transplantation is carried out during the infection period. During the repair period, only some residual and sporadic small wounds were repaired, and measures and exercises were taken to prevent contracture and deformity of some joints and functional parts. Extensive deep burns take a long time to recover, and some need plastic surgery. I wish you the best of health!