【Animal Modeling】-Small pig scald model

  (1) Feeding method Before the experiment, the mini-pigs were fasted for 12 hours, and after anesthetized by intraperitoneal injection of 50g/L thiopental sodium at a dose of 0.7ml/kg body weight, the back was shaved and the area was enlarged by 40cm. ×25 cm Once the water temperature (100°C) of the super temperature regulator is constant, the probe (copper, round, 18 cm in diameter, 2.54 cm in area) will be burnt down. 2. The probe is connected to a silicone tube wrapped in an insulating material Super temperature regulator) Press lightly. Burn the skin of the piglet's back. The specific burn location is 2 cm away from both sides of the spine, and the number of burn surfaces is determined according to experimental needs.

  (2) Model features After burns at different times, the surface of the wound is round, the shape is the same as that of the burning probe, and it has the same area. The edges are neat, and the boundary between the burn site and surrounding tissues and skin is clear. According to general observation, in the 5-second burn group, the burns were reddish white, and the degree of burns was slightly higher than that of the surrounding normal skin. In the burn group of 10 to 20 seconds, the wound was white and blunt, and the wound was slightly lower than the surrounding skin. Histological observations showed that in the 5s burn group, the dermal cells above the spinal cord cell layer were degenerated and necrotic, and some spinous processes and all basal cells were normal. In the 10s burn group, the entire thickness of the dermis was degraded and necrotic. Separation of epidermis and dermis, superficial dermal hyperemia and edema, mild swelling and degeneration of collagen fibers, and inflammatory leukocyte infiltration; 15-second burn group, epidermis and superficial dermis coagulation and necrosis, after mild swelling and degeneration of dermal collagen fibers, they It will turn red, causing strips, damage to the skin appendages of the superficial dermis and deep skin. The attachments are intact and show histopathological changes similar to two deep burns.

  (3) Comparative medicine This method can prepare a small area of burn on the skin of a small pig with a certain area and depth. Compared with traditional boiling water burns and aluminum rod burns, the biggest advantage of this method is that the edges of the flat surface are very clean, and the boundaries of normal tissues are clearly visible. However, it is difficult to develop standards. Due to boiling water soaking, a small area burns. In many cases, it is easy to cause complete tissue damage, and its burn area is not easy to control. Apply this method to burn for 5-20 seconds. As the burn time increases, the damage to the skin gradually increases, and the depth of damage can reach the epidermis, epidermis and deep dermis respectively. Burns can reach two deep burns within 15 seconds, which is suitable for local medical research on burn healing process and burn healing.