Ltd. in the Kunshan Development Zone, Jiangsu Province, automobile wheel hub light workshop in the production process of the explosion. As of 5 o’clock tonight, the death toll reached 71 people, 186 people were injured, the injured were scattered in 15 medical institutions to rescue, a number of critically ill patients are not out of danger. According to Xinhua, Zhang Qin, chief physician of the burns department at Shanghai Ruijin Hospital, said: “I’ve been practicing burns treatment for 27 years, and I’ve never seen such serious and fatal blast injuries. Some of the injured sent to the hospital have already passed away, and a high mortality rate is expected to follow.” The initial judgment is that it is a corporate safety and production responsibility accident, caused by dust encountering an open flame that triggered the explosion. Early patients should be promptly sent to the hospital to correct the effective circulating blood volume, special attention should be paid to inhalation injuries, blast injuries, burn and punch compound injuries, which is the main cause of early death of patients. When the explosion occurred, the injured are mostly in the vicinity of the explosion. After the explosion produced a huge air wave (i.e., shock wave) attacked the casualty’s chest, chest wall impact lung tissue; due to the principle of reaction, the shock wave past the lungs back to the chest wall, the two pressurized and mitigated the damage, caused by rupture of the lung parenchyma capillaries hemorrhagic, and the ribs corresponding to the surface of the lungs is particularly obvious. Shock wave itself directly on the human body caused by the injury is called a concussion injury. At the same time, the dynamic pressure of the shock wave (high-speed airflow impact) will be thrown and hit the human body as well as the role of other objects and then cause indirect damage to the human body. Shock wave of high temperature can cause surface or respiratory burns. Shock waves can cause damage to all tissues and organs of the body, with air-containing organs being particularly susceptible to damage. The degree of tissue and organ damage depends on the size of the pressure peak, the duration of positive pressure and the speed of pressure rise. Clinical characteristics of impact injuries: ① multiple injuries, often multiple injuries or compound injuries, complex injuries, ② light outside and heavy inside, the body surface can be intact, but there are obvious symptoms and severe visceral injuries. ③ Rapid development, mostly within 6 hours after the injury can also be developed to the peak within 1 to 2 days after the injury, once the body compensatory dysfunction, the injury can be a sharp turn, difficult to save. In theory, impact injuries include both shock waves of overpressure – negative pressure caused by direct injury that is, concussion injuries, including dynamic pressure-induced injuries and burns, but clinically, impact injuries and concussion injuries are often confused. Explosion generated by high-pressure air or water waves impact on the chest can make the chest wall impact lung tissue, immediately after the high-pressure negative pressure wave can also make the lungs collide with the chest wall, resulting in lung contusion, pulmonary capillary hemorrhage, small bronchial and alveolar rupture, so that the alveoli for the blood and tissue fluid filled with the loss of ventilation and dispersion function, severe hypoxia; extensive pulmonary edema of lung tissue. In severe cases, there is pulmonary fracture, which can cause hemothorax and pneumothorax. In addition, the gas can also enter the pulmonary blood circulation caused by air embolism; if a large number of air embolism into the cerebral artery and coronary artery, can cause immediate death. Burning and shock compound injury refers to the personnel at the same time or successively by the direct or indirect effect of heat and shock waves and the occurrence of burns and shock injuries compound injury. In the instant of material explosion quickly form a huge energy release of the chemical reaction process, resulting in high temperature and high pressure of the rapid expansion of the gas, resulting in the destruction of the surrounding media, deformation and displacement, the explosion source of the air around the rapid expansion of the media to form three compression wave, the overlap of the formation of three shock waves; explosion at the same time as the surrounding temperature is also rising dramatically; speed of flying fragments of a variety of injury-causing factors caused by the overlap and composite damage. In times of war, especially nuclear war, shock injury is quite common. In the peacebuilding period, mostly in chemical plants, mines or ammunition depots and other explosions. In the clinic, pure shock wave injury is often less common, the vast majority of which is in the form of composite injuries manifested. Burning shock compound injury mechanism 1, shock wave injury; shock wave injury, including primary injury, secondary injury and three injuries three mechanisms. Lungs are susceptible to shock injury of internal organs, due to shock injury external signs are not obvious, and shock wave injury injury is complex, rapid development, so the shock injury to the chest blast injury should be given sufficient attention. 2. thermal: the explosion of the original explosion can instantly produce huge energy, so that the surrounding gas temperature rises sharply, the formation of high-temperature heat, resulting in body surface burns. Therefore, the burn punch compound injury and the end mainly depends on the severity of the burns, and severe burn punch compound injury often shows two injury factors aggravate each other, promote each other, that is, the so-called composite effect of the results. The clinical characteristics of more than moderate burn and shock compound injury 1, shock severe, and accompanied by multiple organs and parts of the fatal damage of serious damage, high mortality rate. In the instant the shock wave effect can produce obvious biological effects, especially close to the explosion injury, its shock wave running at high speed generated by the dynamic pressure of the throw, impact, direct extrusion, the injured fall, displacement and organ rupture bleeding and bone fractures; debris injuries; as well as the center of the explosion of the flames and scorching gases caused by skin burns and inhalation injuries. 2, the scope of trauma, the rapid development of injuries, blood volume loss, the degree of shock, long time. 3, the incidence of lung impact injury is high, the lung is the main target organ of the shock wave effect, but also the vulnerable parts of the burn shock compound injury. Lung microvascular endothelial cell damage in burn and shock compound injury is significantly aggravated compared with simple burn or shock wave damage. The main manifestations of pulmonary hemorrhage, alveolar and interstitial edema, alveolar rupture, ventilation and ventilation dysfunction, or has caused irreversible hypoxemia. Whole body or chest exposure to the shock wave in the circulation of blood is instantly pressed heart, lungs, small blood vessels within the pressure has nearly a hundredfold increase, resulting in lung injury. Early X-ray chest radiographs after burn and shock compound injury show increased lung texture, coarsening, blurring, decreased transmittance, uneven density and shallow block or flaky cloudy flocculent shadows, which diminish or disappear 4-8 days after the injury, pulmonary alveoli and fluid pneumothorax, mediastinal emphysema and rib fractures. Chest CT examination within 6 hours after the injury showed that the detection rate of alveolar focal emphysema, pleural effusion, mediastinal emphysema was higher than that of X-ray chest radiographs, especially a small amount of pericardial effusion was not easy to be detected on the X-ray radiographs; the cloudy flocculent shadows with increased density suggested that alveolar and interstitial hemorrhage and edema. 4.Infection occurs early. Systemic infection is the main complication of burn and punch compound injury, and also the main cause of death. According to the statistics of 46 cases of burn and punch compound injury patients, the incidence of systemic infection is 19,57%, of which the morbidity and mortality rate is 88,89%, which is significantly higher than that of simple burn patients. 5, more complications, the chance of MODS increased. Burning and rushing compound injury patients often combined with serious internal environmental stability disorders, hypoxemia, and coagulation mechanism disorders. Burning and rushing compound injury as the first blow, resulting in hypovolemic shock, hypoperfusion, ischemia and reperfusion injury, although the patient through the shock, but the heart, lungs, liver, intestines and other organs are still in “hidden shock”, ischemia and hypoxia, hypoxic metabolism produces lactic acid, a large number of oxygen radicals are released. Various types of immune cells in the body are in an “activated” state. If serious infection and sepsis occurs, it can lead to MODS. Diagnosis The lung and heart type is the main manifestation. 1, history of explosion burns, impaired consciousness and dyspnea immediately after the injury; 2, skin swelling in the chest area with extensive subcutaneous hemorrhages; 3, dry and wet rhonchi heard in the lungs; 4, persistent hypoxemia; 5, blood gas analysis of hypoxemia, metabolic acidosis with respiratory alkalosis; 6, blood, erythrocyte pressure volume changes; 7, cardiac enzyme profiles, including CK-MB, cTnI measurement; 8, X-ray chest radiography and CT examination shows the activation of various types of immune cells in the body, which can lead to MODS. X-ray chest radiographs and CT examinations show patchy cloudy shadows, pleural effusion, hemopneumothorax, and so on. Treatment Burn itself can cause a series of secondary reactions such as stress ulcers, systemic inflammatory response syndrome, and even sepsis and MODS, while shock waves can further cause damage to parenchymal and cavity organs by generating pressure difference, implosion effect, rupture effect, inertia, throwing and impact under its overpressure, negative pressure and dynamic pressure. Burning and rushing compound injury not only includes surface burns, trauma, but also a series of pathological changes in the internal organs, such cases, especially when the compound large-area burns, the treatment process is more difficult than simple burns. Treatment principles: light to moderate burns and punch compound injury according to the principles of burn treatment, treatment is relatively smooth, rarely occur visceral complications. Heavy, especially severe burn and punch compound injury treatment in the early stage should be combined with the clinical situation, focusing on the lung impact injury and correct shock rescue measures. Measures: 1, the prevention and treatment of shock Resuscitation rehydration can basically be supplemented according to the expected amount of simple burns, but appropriate supplementation of crystalloid and a certain amount of whole blood. However, extra-heavy patients require rapid rehydration, striving to enter 2000-2500ml of fluid in the first 2 hours. Sodium lactate Ringer’s solution is used first to reduce the degree and duration of shock, followed by whole blood and plasma to increase colloid osmotic pressure and reduce plasma extravasation. It has been reported that the amount of rehydration for the first 24 hours was 2, 0-2, 5 ml/Kg, 1% TBSA crystals, colloidal fluid; the amount of rehydration for the second 24 hours was 2/3 of the amount for the first 24 hours. According to the results of experimental research suggests that the burn and punch compound injury and erythrocyte membrane hardness increases, deformability decreases, blood rheological properties deteriorate, given HSD (static injection of 7, 5% sodium chloride solution for 15min), can significantly reduce the whole blood viscosity and whole blood reducing viscosity, can significantly expand the volume, peripheral vascular resistance decreases, and improve the hemodynamic status. During resuscitation, urine output (1-2ml/Kg, h), hematocrit, electrolytes, oxygen saturation (SpO2) and hemodynamic parameters were closely monitored. Secondly, in order to improve myocardial contractility and cardiac output in the early stage of burn-and-shock compound injury, dilate renal and mesenteric blood vessels, and improve renal blood flow and glomerular filtration rate, trace dopamine (2-5ug/Kg, min) or dobutamine can be intravenously injected. Scopolamine (654-2) can also be taken in combination with dexamethasone. 654-2 20mg IV over 6 hours improves microcirculation, improves tissue cell oxygen supply, and reduces the release of inflammatory mediators. Dexamethasone 10-20mg static injection, once every 8 hours, 3 days after the discontinuation, can improve the body’s stress and tolerance to traumatic shock hypoxia. Experiments have proved that the combination of the two can improve the degree of disturbance of hemodynamic indexes, reduce the lung body index, and reduce the degree of pulmonary edema. 2, adequate oxygen supply Burning and impact compound injury patients should establish a good airway early. Anyone with pulmonary impact injury and/or inhalation injury should be tracheotomized as early as possible (i.e., before 6 hours after the injury or if airway obstruction occurs) to ensure the patency of the airway. According to the parameters required for oxygen supply, i.e., DO2=1,34×Hb×CO×SaO2, efforts should be made to improve Hb, CO and SaO2. ensure that Hb is at 100-120g/L; Hct33-35%, SaO2 is positively correlated with PaO2 in a considerable range, and to improve PaO2, it is necessary to ensure that the airway is patent and to appropriately increase the concentration of inhalation oxygen (FiO2) so that the oxygenation index ( PaO2/ FiO2) is greater than 300 mmHg or more, so as to ensure good oxygen supply to important organs and tissues. To increase CO (cardiac output) lies in increasing preload (rehydration and volume expansion), appropriately decreasing afterload as well as applying positive inotropic drugs to increase the volume per beat. To do this, monitor blood gas analysis at regular intervals. If the respiratory rate exceeds 35 breaths/min, PaO2 has a tendency to decrease, and PaO2 is lower than 80-70 mmHg, mechanical ventilation should be used in time, and PEEP 5-200 pxH2O should be added if necessary.In order to ensure the airway patency, in addition to timed airway humidification and removal of airway secretion, fiberoptic bronchoscopy once a day is performed to observe airway and lung lesions, and at the same time alveolar large-dose lavage is taken plus exogenous pulmonary surface active substance (PS). And closely observe the dynamic changes of ARDS. 3, the treatment of trauma According to the evolution of the pathophysiological changes of impact injury, the lung injury began to reduce or improve 3 days after the injury, so in about 3 days after the injury of third-degree burn wounds for 1-2 times a large area of scab cutting and particulate skin implantation, to remove the inflammatory mediators of the charred scabs and the sub-scab oedema fluid and endotoxicity, to block or alleviate the out-of-control inflammatory response, to reduce the incidence of generalized sepsis and visceral complications, and to improve the Healing rate. For the treatment of injured organs, it is required to shorten the waiting time for surgery, and the necrotic tissues without blood transport should be completely removed, and the organs that can not be repaired, such as spleen and intestinal tube can be removed, and the liver, pancreas, and one side of the kidneys can be partially resected or repaired depending on the injury, and it is prudent to do one-stage anastomosis for the injured colon in those who are in severe shock. Those with hemopneumothorax causing respiratory distress should immediately perform closed chest drainage. 4.Apply early enteric nutrition Early enteric nutrition can improve intestinal blood perfusion after burn injury, maintain the structure and function of intestinal mucosa, reduce intestinal damage and endotoxin displacement. Reduce enterogenic hypermetabolism. At the same time, oral glutamine and arginine. 5, prevention and treatment of infection burn and punch compound injury to lung injury is the most serious, pulmonary hemorrhage and alveolar and interstitial edema, airway mucosal barrier loss of defense, resident bacteria and nosocomial pathogens (including fungi) leading to respiratory tract infections is not uncommon. Therefore, targeted antibiotics are used to regulate the body’s immune function and prevent or control infections as soon as possible. Prevention Before discovering the explosion, if it is too late to take cover, you should immediately lie down on the ground or in a nearby alcove, with your feet toward the point of explosion. In this way, in the fan-shaped shock wave outside the dead zone, can reduce or save the shock wave damage. The prevention of this disease is the main thing is to actively prevent the occurrence of various complications. For example, for patients with burns, actively control the infection to prevent the occurrence of lung infection. For patients who need to be on lung ventilator, the principle of ventilator “morning machine, early withdrawal, personalized” should be followed. We should strive for early release from the ventilator to avoid ventilator dependence. For patients suspected to be at risk of airway obstruction, tracheotomy can be performed earlier. Standby at any time to serve the front-line patients, may the burn patients turn to safety as soon as possible, may the burn colleagues take care of their health, keep up the good work, we will always be your backing.