The four basic techniques of trauma first aid are hemostasis, dressing, fixation and transportation. When implementing on-site trauma rescue, on-site personnel should be in the humanitarian spirit of saving lives and helping the injured, while notifying the nearest hospital, to calmly and quickly carry out on-site first aid work, the principles are: first after rescue, first heavy and then light, first urgent and then slow, first near and then far; first stop bleeding and then dressing, then fixed and then transported. First, the type of bleeding: blood from the body surface wound outflow, called external bleeding, easy for people to find; and deep tissue, visceral injury bleeding, blood into the tissue or body cavity internal bleeding, not easy for people to find, more dangerous. Among all kinds of bleeding, arterial bleeding is the most dangerous and must be stopped in time. According to the different damage vessels, can be divided into: l. Arterial bleeding: the characteristics of the wound is a jet pulsating outward gush of bright red blood. 2, venous bleeding: the wound continues to spill outward dark red blood. 3, capillary bleeding: bright red blood oozing outward from the wound. Second, the clinical manifestations of bleeding The blood of adults accounts for about 8% of their body weight. When the total blood loss reaches more than 20% of the total blood volume, the casualty appears pale, cold sweat, cold hands and feet, shortness of breath, panic and shortness of breath, etc., the pulse is fast and thin, blood pressure drops, followed by hemorrhagic shock. When the bleeding volume reaches 40% of the total blood volume, it is life-threatening. Third, the method of hemostasis 1, pressure bandage hemostasis method: with sterilized gauze or clean towels, cloth folded into a slightly larger than the wound pad cover the wound, and then bandages or folded into strips of cloth or triangular towel tightly wrapped, its elasticity to achieve the purpose of hemostasis is appropriate. This method of hemostasis is mostly used for venous bleeding and capillary bleeding (see Figure 3). When the wound is in the elbow fossa, axillary fossa, fossa, groin, it can be fixed on the trunk with pressure bandage to stop bleeding after adding padding to the flexed limb (see Figure 4). Pressure bandage hemostasis method is applicable to arterial bleeding in the upper and lower extremities, elbows and knees, but this method is not suitable when there is a fracture or suspected fracture or joint dislocation. 2, acupressure hemostasis method: acupressure hemostasis method is a simple and effective temporary hemostasis method, it is based on the direction of the artery, in the proximal end of the bleeding wound, used to finger pressure at the artery, to achieve the purpose of temporary hemostasis. The finger pressure hemostasis method is applicable to arterial bleeding in the head, neck, and extremities, and can be divided into: (1) head bleeding compression method: the method is to compress the temporal artery with the thumb in front of the injured side of the ear, aligned above the inferior frontal joint (see Figure 5). (2) Head and neck hand hemorrhage compression method: the method is to compress the common carotid artery on the injured side backward with the thumb (see Figure 6), but not to compress the common carotid artery on both sides at the same time, otherwise it will cause cerebral oligohemorrhage necrosis. (3) Facial hemorrhage compression method: use the thumb to compress the facial artery at the angle of the mandible (see Figure 7). (4) Scalp hemorrhage compression method: For anterior scalp hemorrhage, compress the temporal artery above the mandibular joint in front of the ear (see Figure 8). For posterior scalp hemorrhage, compress the postauricular artery slightly lateral below the postauricular eminence (see Figure 9). (5) Axillary and shoulder bleeding compression method: compress the subclavian artery with the thumb downward in the supraclavicular fossa aligned with the first rib (see Figure 10). (6) Compression method for upper arm bleeding: elevate the affected limb with one hand and compress the brachial artery on the medial side of the upper arm with the thumb of the other hand (see Figure 11). (7) Forearm hemorrhage compression method: compress the end of the brachial artery medial to the biceps tendon in the elbow fossa on the injured side with the thumb (see Figure 12). (8) Subpalmarine hemorrhage compression method: use two fingers to compress the ulnar artery and flexor artery at the wrist, respectively (see Figure 13). (9) Lower extremity hemorrhage compression method: compress the femoral artery slightly below the midpoint of the groin with the thumbs of both hands overlapping backward with force. (See Figure 14) (10) Foot bleeding compression method: Use the thumbs of both hands to compress the dorsalis pedis artery on the lateral aspect of the mother longus tendon and the posterior tibial artery between the medial ankle and Achilles tendon, respectively. (See Figure 15) There are too many diagrams to understand at home, so I’ll pass one up! Just understand the meaning! It is the vessel that presses the bleeding side! (Near the heart position) 3, tourniquet hemostasis method: tourniquet hemostasis method is a fast and effective way to stop bleeding, but it is only applicable to bleeding in the large arteries of the extremities that can not be stopped with pressure. The method is to use a rubber tube or cloth wrapped around the muscle above the wound, its tightness to feel the distal artery pulsation, the wound just hemostatic appropriate, too loose no hemostatic effect, too tight will affect blood circulation, easy to damage the nerve, resulting in limb necrosis. On the tourniquet wounded, must be marked in an obvious part of the tourniquet on the site and time; on the tourniquet time more than two hours, to relax every hour, each time – 8 minutes, in order to avoid relaxing the tourniquet when a lot of bleeding, relaxation period can be replaced by acupressure method of temporary hemostasis. (1) rubber tourniquet hemostasis method: commonly used a 1-meter-long rubber tube, first with a bandage or cloth pad flat on the site of the tourniquet, both hands will be the middle section of the tourniquet properly stretched. (2) Cloth tourniquet hemostasis method: commonly used triangular towel, cloth tape, towel, sleeve, etc. flatly wrapped around the limb with cloth pad, pulled tight or tightened with a “stick, chopsticks, pencil”, etc. fixed. (See Figure 17) (d) for internal bleeding or suspected internal bleeding of the casualty, the casualty should be absolutely quiet and immobile, padding the lower limbs, the conditions can be infused first, the casualty should be quickly sent to the nearest hospital for treatment. Bandaging (a) the purpose and precautions of bandaging The purpose of bandaging is to protect the wound, reduce infection, fix the dressing splint, hold the injured limb, reduce the pain of the casualty, prevent serious complications such as stabbing blood vessels, nerves, etc. Compression bandaging also has the role of compression to stop bleeding. The dressing requires light and fast, accurate and firm movements, and the purpose of the dressing should be clarified before the dressing in order to choose the appropriate dressing method and make preliminary treatment of the wound. The tightness of the dressing should be appropriate, too tight affects blood circulation, too loose will move off, the location of the dressing material knotted or fixed by other methods should avoid the wound and the location of sitting and lying under pressure. The dressing for fracture braking should expose the end of the injured limb in order to observe the blood circulation of the limb. (B) Bandaging materials 1. Triangular towel: Use a square of cotton cloth with a side length of l meter and cut it along its diagonal to make two triangular towels. Fold the top corner of the triangular towel to the center of the bottom edge, and then) Fold into a strip of a certain width according to the actual needs of the bandage. If the top corner of the triangle towel folded to the left or right of the center of the bottom edge, it becomes a dovetail towel, the size of the angle can be seen in the actual bandage needs. 2, bandage: our standard bandage 6 meters long, the width of 3, 4, 5, 6, 8, 10 cm 6 specifications for the actual needs of bandage selection. One end of the bandage rolled up for a single-headed band, from both ends rolled up for a double-headed band. Its length can be wrapped depending on the needs of the site. When there is no conventional bandage material, the clothes, handkerchiefs, towels and other handy materials can be used for bandaging. (C) the method of wrapping 1, head cap wrapping method: the bottom edge of the triangular towel folded inward about two fingers wide, dry on the forehead eyebrows, the top corner backward pull cover the top of the head, the two bottom edges along the top of the two ears backward dry pull to the lower part of the occiput, left and right cross and press the top corner around to the forehead knot fixed (see Figure 18). 2, head, ear hood type bandage method: the top corner of the triangular towel tied a knot, placed in the center of the forehead, the head set into the hood, downward pulling the two bottom corners, and then the bottom edge outward counter-tie 2 – 3 finger width of the edge, left and right cross and wrap around the jaw, around to the occiput after the knot fixed. 3, triangle towel eye bandage method: bandage single eye, the triangle towel folded into a four-finger-wide band, placed obliquely on the injured side of the eye, from the injured side of the ear around to the occiput, pulled up through the healthy side of the ear to the forehead and the other end of the cross reflex around the head for a week, in the healthy side of the ear before the upper end of the Ding knot fixed (see Figure 20). When wrapping both eyes, the center of the banded triangular towel is placed in the occipital area, and the two bottom corners are pulled under the ears toward the eyes, and one eye is wrapped around the bridge of the nose, forming an “8” shape by the two ears above the occipital area, and then wrapped around to the lower collar and fixed with a knot (see Figure 21). 4, triangle towel chest bandage method: the top corner of the triangle towel placed on the injured side of the shoulder, the two bottom edges in front of the chest pulled across to the back knot fixed, and then with the top corner before the Ding knot fixed (see Figure 22). 5, triangle towel lower abdomen wrapping method: the top corner of the triangle towel facing down, the bottom side of the abdomen across the abdomen, the two bottom corners in the back of the waist knot fixed, the top corner of the inner two legs pulled to the back of the waist and the bottom corner knot fixed (see Figure 23). 6, swallowtail scarf shoulder wrapping method: single shoulder wrapping, the triangle towel folded into about 80 degrees angle of the swallowtail scarf, the angle facing up, backward corner pressed forward corner, placed on the injured side of the shoulder, the bottom edge of the swallowtail around the upper arm in front of the axillary knot fixed, the two corners of the swallowtail were pulled through the chest and back to the opposite side of the axillary knot fixed (see Figure 24). When wrapping both shoulders, the triangle towel is folded into two tail corners equal to the size of the double swallowtail towel, the angle facing upward, aligned with the back of the neck right in the middle, the left and right double swallowtail from the front to the back were wrapped around the shoulders to the axilla, in the back of the axilla knot fixed (see Figure 25). 7, triangular towel hand, foot bandage method: bandage knee, elbow, the triangular towel tied folded into a slightly wider than the wound band, diagonally placed in the wound Hand, both ends pressed up and down around the limb a week, in the limb or medial knot fixed (see Figure 26). Wrapping hands and feet, the bottom edge of the triangular towel across the wrist (ankle), the palm of the hand (foot bottom) down in the center of the triangular towel, the top corner of the reflexive cover the back of the hand (foot), the two bottom corners cross and press the top corner around the limb a circle, reflexive top corner after knotting fixed (see Figure 27). 8, triangular towel hip bandage method: the top corner of the triangular towel face down on the injured side of the waist, a bottom corner wrapped around the thigh) root and the top corner inch Ding knot, the other bottom corner lifting the waist and the bottom edge of the knot fixed (see Figure 28). 9, bandage wrist, chest, abdomen ring wrap method: bandage wrist, chest, abdomen and other parts of roughly equal thickness, the bandage for the ring overlap winding, each ring will be on a ring of bandage completely covered, in order to prevent the bandage from slipping off, the first circle of bandage can be placed diagonally, around the second or third circle will be diagonally out of the circle of bandage corner back tie to the circle of the corner overlap around fixed (see Figure 29). 10, bandage extremity spiral wrap method: bandage extremity, the bandage for a certain interval up or down spiral around the limb, each spin around a circle will be on a circle of bandage cover 1/3 or 2/3. this method is commonly used to fix the extremity splint and dressing (see Figure 30). 11, bandage spiral reflexive wrap method: wrap thick and thin differences in the forearm, calf, in order to prevent the bandage from slipping off, wrap more firmly with the spiral reflexive method, this method and spiral wrap method is basically the same, but each circle must be back tie bandage once, back tie with the left thumb pressed back tie, the right hand will bandage reflexive downward pull tight around the limb, but the bandage back tie to avoid wounds and bone protrusions (see Figure 31)