动物造模,电烧伤动物模型 z-bio 2022-01-14 623

　　Human electric burns are usually severe high-voltage electric burns. High-voltage electrical damage not only has different degrees in nature and normal burns, but also has a certain degree of complexity in determining conditions and handling and repairing local damage after damage.

　　(1) Copy method Remove the part about 6 cm x 8 cm from the inner thigh coat of the two hind limbs of the experimental rabbit, and place copper electrode plates (3 cm x 3 cm) on both sides of the part to solve this problem. The entrance is on the right and the exit is on the left. The electric shock can be performed without anesthesia. The shock time is 5 seconds, the rated voltage is 10kV, the actual passing current is (2±0.15)A, and the skin resistance is 2500Ω. The electrode plate is released immediately after the shock. Shock.

　　(2) Model feature appearance inspection: After removing the electrode plate, compare the local skin with the surrounding non-contact surface. Clearer. The outer circumference is a thin black ring, slightly higher than the edge, and has one or two carbonization centers. Near the center is gray, hard, necrotic skin, slightly sunken. It cuts the skin, touches the muscles, and is slightly swollen, uneven skin tone, gray and red, loose tissue, easy to tear, and inelastic. The blood vessel embolism in this layer is small, the deep muscles are slightly dark red, and local coagulation can be seen. The extent of muscle damage is unknown. After 4 to 28 hours of injury, the boundary of the burned area of the outer skin becomes more obvious; the entire wound is gray-white, but the exudation is not obvious; the local swelling is increased, the texture is hard, and it is the favorite of leather. Secondary embolism or coagulation of larger blood vessels occurs. The spread of tissue necrosis gradually expanded, damaging the entire muscle, especially deep tissue necrosis. Agglutinative necrosis of normal muscle fibers, ecological tissue and flaky muscle coexist. 5-7 days after the injury, skin ulcers, muscle splits, local swelling gradually reduced, the wound smelled, the infection was serious, the pus was lost, and the inflammatory infiltration was normal, involving various areas. Dark gray or deep red bleeding points will appear on the wound, the skin will be deliquescence, and the degree of exfoliation of burn tissue will increase. Erosion occurred in the deep tissues, and obvious vascular embolism was observed. All nerves, tendons, etc. are exposed. The skin of normal rabbits is shiny and smooth, the muscle bundles are arranged regularly, the color is uniform, and the direction of the blood vessels is clearly visible. Optical microscopy showed that the skin showed vitreous changes in the early stages of electric burns, subcutaneous coagulation and necrosis, interstitial congestion, edema, blurring of muscle fiber structure, and fusion of myofilaments with masses or vesicles. Extensive purulent necrosis of the superficial dermis can be seen 24-48 hours after injury. The deep tissue is homogeneous and infiltrated by inflammatory cells. Vascular congestion is obvious, most of the small arteries and veins have bleeding, most of the muscle fibers near the lesion are coagulated and dissolved, and the muscles have obvious congestion, congestion and neurodegeneration. 3-5 days after injury, epidermal necrosis and ulcers, massive subcutaneous suppuration, thrombosis of blood vessel walls, necrosis of certain arteries, interstitial congestion and hemorrhage, and collapse of certain nerve cords. Muscle fibers include local scars, partial dissolution, large necrotic areas in the central area, and individual fat changes and vacuoles. After 7 days, many granulation tissues were clearly repaired. Normal section results: the skin structure is perfect, the muscle fibers are arranged neatly, the nucleus is normal, and there is no hyperemia.

　　(3) Comparative medical burns also cause progressive necrosis, but the theory and practice of burns cannot explain common clinical phenomena, such as progressive necrosis of electric shock tissue or sandwich necrosis. Most electrical burns seen in clinical practice are electrical burns above 10,000V. In the experiment, the nature of the local damage after the electric shock is the burning of the electric contact instead of the arc burning, because the arc burning can be avoided. Basically, this is due to electrical burns caused by careless operations on the daily system lines. The burn status of local wounds after electric burns is basically the same as that of high-voltage electric burns in clinics, and so is the development of wounds. This shows that the use of high-voltage discharge devices in animal experiments can basically reflect the clinical situation of electric burns.