Crush injury often occurs in severe extrusion, smashing or bandage is too tight and fracture jamming damage to blood vessels, so that the tissue gap hematoma, muscle tissue ischemia, capillary permeability increases, inter-tissue exudate increase, limb appears highly swollen, pressure increases, resulting in ischemia and hypoxia, so that the muscle and nerve degeneration and necrosis, resulting in contracture of limbs, dysfunction, or even necrosis and amputation. So what related examination do you need to do for crush injury? 1, etiology: crush syndrome often occurs in severe extrusion, smashing or bandaging too tight and fracture compression damage to the blood vessels, so that the tissue gap hematoma, muscle tissue ischemia, capillary permeability increases, inter-tissue ooze increases, the limb appears highly swollen, pressure increases, resulting in ischemia and hypoxia, so that the muscle nerves degenerate necrosis, resulting in limb contracture, dysfunction and even necrosis and amputation. Nerve function abnormality occurs 30 minutes after ischemia, complete ischemia 12-24 hours of permanent loss of nerve function, muscle ischemia 2-4 hours of functional changes, and ischemia 4-12 hours of permanent loss of function, muscle ischemia more than 4 hours of obvious myoglobinuria, muscle ischemia more than 12 hours of ischemia ischemia surely appear ischemic myoclonus, sensory-motor Muscle ischemia is more than 12 hours, ischemic myoclonus, sensory-motor dysfunction, and even limb necrosis can occur. Clinical manifestations and nursing observation: ischemic myoclonus mainly occurs in the forearm and calf, the damaged interval area has obvious swelling, redness and pressure pain or tension blisters, skin sensory disorder or loss in the distribution area, and the pain of the affected muscles can be aggravated by the ischemia when they are passive activities. Early signs and symptoms are not obvious, and arterial pulsations may be present. In the late stage, the arterial pulsation may be weakened or disappeared due to the high swelling of the tissue and increased pressure. In the case of direct vascular injury, arterial pulsations may disappear after the injury. Fascial syndrome may have the following manifestations depending on the site of occurrence: (1) forearm interval area: (1) when it occurs on the dorsal side, localized tissue tension, tenderness, weakness of the thumb and finger extensor muscles, and pain caused by passive flexion of the thumb and fingers; (2) when it occurs on the metacarpal side, tissue tension and tenderness on the palmar side of the forearm, weakness of the thumb and finger flexor muscles, and pain caused by passive extension of the thumb and fingers, as well as loss of sensation of the skin in the area of distribution of the ulnar nerve and the median nerve. (2) calf intervals: ① anterior intervals of pressure rise, in addition to the anterior side of the calf tissue tension and tenderness, there can be a loss of sensation in the distribution area of the deep branch of the peroneal nerve, extensor digitorum profundus and tibialis anterior muscle weakness, passive flexion of the toes caused by pain; ② lateral intervals of pressure rise, the superficial branch of the peroneal nerve and the deep branch of the distribution area of the skin loss of sensation, peroneus brevis muscle weakness, inward roll of the foot when the pain caused by local skin tension and tenderness in the lateral calf at the peroneum. (iii) Posterior calf interval zone syndrome, divided into deep and superficial, superficial interval zone in the flounder muscle and gastrocnemius muscle weakness, dorsiflexion of the ankle joint, causing pain, swelling and tenderness in the back of the calf, deep interval zone in the dorsiflexion of the toes and posterior tibialis muscle weakness, extending the toes, causing pain, loss of skin sensation in the distribution area of the posterior tibial nerve, and tension and tenderness in the tissues of distal medial calf between the Achilles tendon and tibia bone. 3, preventive care and treatment: first of all, for patients with obvious limb trauma, medical personnel should have a high sense of responsibility and mission, the patient should be detailed and repeated careful examination, do not touch the arterial pulsation to relax all vigilance, especially for patients with bone fracture and nerve injury, there can be severe pain and loss of sensation in the region, due to the gradual rise in pressure in the tissue in the early days, although it can make the small arteries close, but it can not affect the main arteries of the limb. Due to the early gradual increase in intra-tissue pressure, although the small arteries can be closed, but can not affect the blood flow of the main arteries of the limb, so the distal end of the affected limb can still touch the arterial pulsation, capillary filling can also exist, do not mistakenly think that there is no limb blood transport disorders or no interstitial zone syndrome occurs. Once the diagnosis of fascial interstitial zone syndrome and extrusion syndrome occurs, it is necessary to immediately release the compression, report to the competent doctor, the affected area will be fully and thoroughly incised and decompensated, do not advocate the elevation of the affected limb, to solve the venous return, this approach is wrong, which is not only ineffective, but also aggravate the existing lesions, because the elevation of the affected limb will reduce the blood pressure of the arteries in the limb, exacerbate the lead to the closure of the small arteries, so that the tissues become more ischemic and anoxic, the Promote the development of fascial septal zone syndrome, at the same time pay attention to watch to prevent renal failure, due to tissue ischemia and hypoxia, tissue necrosis appear myoglobinuria, toxin absorption and muscle necrosis, a large amount of intracellular potassium into the circulation, coupled with renal failure potassium excretion difficulties, hyperkalemia damage to the myocardium, and acidosis and methaemoglobinaemia can occur, can lead to life-threatening.