Liver trauma

　　1. Etiology

　　Hepatic trauma, generally classified according to the cause of injury, is divided into open and closed injuries. Open injuries usually include stab wounds and firearm injuries. Stab wounds are relatively mild with a low mortality rate. Firearm injuries are open injuries caused by projectiles (bullets, shrapnel, ball bearings) propelled by gunpowder, which are common in battlefield injuries, and liver firearm injuries are the most common among abdominal firearm injuries. Open injuries can also be divided into blind-bore injuries and贯通 injuries. Closed abdominal injuries are mostly caused by blunt trauma, mainly due to collisions and compressions, and are common in road traffic accidents, building collapses, and occasionally in falls from heights, sports injuries, or beating injuries.

　　Due to the fact that abdominal closed injuries often have injuries to other organs in addition to liver trauma, and there are no signs of injury on the abdominal surface, the diagnosis is relatively difficult, leading to delayed treatment. Therefore, blunt trauma is more dangerous, and the mortality rate is often higher than that of open injuries.

　　Second, pathogenesis

　　The early pathological and physiological changes of liver trauma are mainly bleeding, hemorrhagic shock, and choleperitoneum. The latter not only increases the loss of extracellular fluid but also affects the normal coagulation mechanism, causing secondary hemorrhage and infection.

　　The site of liver laceration is often at the attachment of the liver surrounding ligaments, or consistent with the direction of the ribs and spine. Closed liver trauma mainly causes the following three types of injuries.

　　1. Subcapsular hematoma:If the liver parenchyma is ruptured on the surface while the liver capsule is still intact, the blood accumulates under the capsule. The size of the hematoma varies, sometimes containing 2-4 liters of blood. If secondary infection occurs, it can form an abscess. Once the capsule is ruptured, it becomes true liver rupture. Sometimes the hematoma compresses the liver parenchyma, causing large areas of liver tissue necrosis.

　　2. Central liver rupture:The central part of the liver parenchyma is damaged and ruptured, and the superficial tissue is still intact, often accompanied by the rupture of liver vessels and bile ducts, forming a large intrahepatic hematoma and bile stasis, compressing the tissue and causing extensive necrosis. It can also secondary infect or communicate with large intrahepatic bile ducts, leading to biliary hemorrhage.

　　3. True liver rupture:Both the liver parenchyma and liver capsule are ruptured, and blood and bile directly flow into the abdominal cavity, but the degree of injury and pathological changes vary greatly, and can be divided into: ① Liver parenchymal contusion and laceration, single or multiple lacerations, regular or irregular or stellate lacerations, simple liver parenchymal injury or combined with intrahepatic or posterior large blood vessel injury, etc.; ② Liver parenchymal avulsion injury, the blood supply of the distal liver tissue is impaired, and vitality is lost; ③ Liver parenchymal destruction injury, liver tissue breaks or falls off into the abdominal cavity due to severe injury, losing the normal shape of the liver. Necrotic liver tissue liquefies and becomes infected, forming abscesses in the abdomen.

　　Injuries to both intrahepatic and extrahepatic bile ducts can cause bile to leak out, leading to choleperitoneum. Injuries to large blood vessels in the porta hepatis can cause liver ischemia and acute massive hemorrhage in the abdominal cavity.

　　1. Infection:The most common cause and also the main cause of late-stage death. All firearm injuries are infected because when the projectile penetrates the tissue, it can bring dirt into the wound. In addition, liver wound bleeding, bile leakage, liver necrosis, and combined injuries of hollow organs can all lead to infection. The types of infection are generally divided into subphrenic abscess, intrahepatic abscess, pelvic abscess, incisional suppuration, pleural abscess, or systemic abscesses in other parts. The liver has a rich blood supply, and once infected, patients quickly develop severe symptoms of intoxication, such as high fever, anemia, hypoproteinemia, and so on. Severe infection can lead to sepsis and shock. Therefore, it is necessary to place a drain tube and keep it unobstructed when treating liver trauma to prevent the accumulation of exudate under the liver. When intrahepatic, subphrenic, or pelvic abscesses occur, use BUS, CT, and other examinations to locate the position, perform puncture drainage, and timely incision and drainage if necessary.

　　2. Bile leak:A common complication. The causes include: incomplete suture of bile duct branches with large liver wounds during liver trauma, incomplete removal of necrotic liver tissue, liquefaction and rupture causing rupture of bile duct branches. When suturing the wound, the bile ducts of the drained liver segment are ligated, which increases the terminal pressure of the bile ducts. In addition to infection and rupture, this leads to bile leakage. If effective drainage is not established, bile peritonitis often occurs, which can lead to shock and death in severe cases. Small bile leaks can be cured with short-term drainage, but large bile leaks may last for a long time, and a few may require reoperation. For those who have formed fistulae, a drainage tube can be placed through the fistula, and a follow-up plan can be determined after造影 examination 3 to 6 months later.

　　3. Rebleeding:It is a major cause of early death in liver trauma. Early bleeding is often related to incomplete hemostasis during surgery. Late bleeding usually occurs several days or a dozen days after injury and is secondary bleeding. It is often related to the necrosis and shedding of non-viable liver tissue. In addition, the input of a large amount of stored blood during liver injury, the decrease in liver function after liver injury, and the disorder of coagulation mechanism are also important reasons for postoperative bleeding. Therefore, it is necessary to achieve complete hemostasis as much as possible during surgery and ensure sufficient drainage. Try to use fresh blood for blood transfusion, and use platelets, coagulation factors, and other substances when necessary. Once secondary bleeding occurs, it often requires reoperation to ligate the hepatic artery or tamponade to stop the bleeding.

　　4. Traumatic biliary hemorrhage:It can occur early after surgery, or several weeks to several months later. Bleeding mostly originates from central liver rupture, hematoma infection after rupture into the intrahepatic bile duct, causing biliary bleeding. The manifestations include hematemesis, melena, and severe upper abdominal colic. The main treatment method is surgery, including hematoma incision and hemostasis, hepatic artery ligation, or hepatic lobectomy, and T-tube drainage of the common bile duct.

　　5. Multi-organ Dysfunction Syndrome (MODS):Mostly caused by severe injury, massive hemorrhage, severe shock, and concurrent infection, mainly manifested as acute renal failure (ARF), acute respiratory distress syndrome (ARDS), and stress ulcer. Therefore, timely anti-shock therapy, correction of internal homeostasis imbalance, and prevention and treatment of infection are very important for preventing MODS in the treatment of liver injury.

　　Patients generally have a clear history of right chest and abdominal trauma, conscious patients complain of pain in the upper right abdomen, sometimes radiating to the right shoulder, feeling thirsty, nausea, and vomiting. The signs and symptoms of liver trauma are mainly hypovolemic shock and peritonitis. Some patients may have massive intra-abdominal hemorrhage, and abdominal distension may also occur. Due to the different causes of injury, the clinical manifestations of liver trauma are also inconsistent.

　　Subcapsular hematoma or small hematoma in the liver parenchyma, mainly manifested as dull pain in the liver area in clinical practice, physical examination may show liver enlargement or a mass in the upper abdomen. If the hematoma communicates with the biliary tract, it manifests as biliary bleeding, causing upper gastrointestinal bleeding. Chronic recurrent bleeding can lead to chronic progressive anemia. If the bleeding within the hematoma continues to increase, the tension of the liver capsule becomes too high, and it suddenly ruptures under the action of external force, causing acute hemorrhagic shock. Therefore, when performing non-surgical treatment for patients with subcapsular hematoma, it is necessary to pay attention to the possibility of delayed bleeding. If the hematoma develops secondary infection, signs and symptoms of liver abscess may appear, such as chills, high fever, and pain in the liver area.

　　In cases of superficial liver lacerations, due to less bleeding and minimal bile leakage, bleeding can usually stop spontaneously within a short period of time. Generally, there is only right upper quadrant pain, and shock or peritonitis rarely occurs.

　　In cases of central liver rupture or extensive liver tissue fragmentation in open liver injuries, it usually involves larger blood vessels and bile ducts, with intra-abdominal bleeding and bile leakage. Patients often present with acute shock symptoms and peritoneal irritation symptoms, such as abdominal pain, pale face, rapid pulse, decreased blood pressure, and reduced urine output. Abdominal tenderness is obvious, and the abdominal muscles are tense. As the bleeding increases, the above symptoms become more severe.

　　In cases of severe liver fragmentation or rupture combined with large blood vessel rupture near the hepatic hilum, such as the portal vein and inferior vena cava, massive bleeding that is difficult to control can occur. Vascular injury can lead to a large amount of dynamic blood loss, causing fatal hypovolemic shock, often resulting in death during the treatment process and losing the opportunity for surgical treatment.

　　Open liver injuries are relatively easy to diagnose, but attention should also be paid to whether there is associated chest and abdominal trauma. Closed injuries with typical hemorrhagic shock and peritoneal irritation signs, combined with the history of trauma, are easy to diagnose. However, for some patients with associated injuries, such as brain trauma with unconsciousness, multiple fractures with shock, and elderly and weak patients with delayed response, caution should be exercised to avoid missed diagnosis. Mild trauma in patients with liver cirrhosis or liver cancer can cause liver rupture, so it should not be taken lightly. Whether there is liver injury associated with abdominal closed injury involves whether to perform laparotomy surgery, so high accuracy is required for diagnosis. When there is doubt about the diagnosis, abdominal puncture, peritoneal lavage, and other auxiliary examinations can often assist in diagnosis.

　　1. Wound treatment should be timely

　　It is essential to treat wounds as soon as possible and thoroughly. Once we are injured, we should immediately wrap the wound with sterile gauze, bandages, and other materials to minimize contact with the air and prevent bacteria from entering the wound. If there are no sterile gauze bandages at home, clean cloth can be used instead. If the wound is bleeding, it should be packed with pressure to prevent bleeding. If the wound is too large and deep with excessive bleeding and foreign bodies, it is necessary to send the patient to the hospital immediately after simple first aid, so that the surgeon can handle the wound, perform debridement and disinfection, and remove the contaminated tissue or foreign bodies.

　　2. Pay attention to nutrition in daily life

　　Nutritional status is also a very important aspect. If the whole body is malnourished, suffering from anemia, vitamin deficiency, and so on, this will directly affect the resistance and healing ability of the wound. And if the resistance is too low, it can also lead to the wound not healing for a long time. The accumulated blood, foreign bodies, and necrotic tissue around the wound not only can cause inflammatory reactions in the wound but also provide favorable conditions for the reproduction of bacteria within the wound, leading to further infection and suppuration.

　　That is the introduction of the methods to prevent traumatic infection. For traumatic infection, it is important to bandage the wound. Learning some nursing methods is very crucial.

　　Early in mild liver trauma, there are no obvious changes. Due to rapid blood loss and blood concentration, many patients do not show changes in hemoglobin levels, but the white blood cell count of liver trauma patients is often >1.5×10^9/L.

　　The diagnostic accuracy of abdominal puncture for closed liver trauma is approximately 70％～90％, and it can be performed repeatedly. The results of abdominal puncture in 113 cases of closed liver trauma at Shanghai Oriental Hepatobiliary Surgery Hospital showed that 105 cases were positive, with a positive diagnostic rate of 92.9％. Before the puncture, it is required to empty the bladder, and perform puncture with a 18～19 gauge thick needle in the four quadrants of the abdomen on the lateral side of the rectus abdominis muscle under local anesthesia. It should be avoided to puncture through scar tissue on the abdominal wall. If non-coagulated blood can be aspirated, it is positive. The puncture result is false-negative, which may be due to blood accumulation in the abdomen not reaching the range of 200～500ml, or it may be because of associated diaphragmatic rupture, causing the ruptured liver to herniate into the chest.

　　Firstly, diagnostic peritoneal lavage:The diagnostic accuracy for abdominal bleeding can reach 93.4％～100％, with 3 methods available:

　　1. Closed abdominal lavage:After emptying the bladder, puncture upward at a 45° angle (with the abdominal wall) at the upper third of the line connecting the navel to the symphysis pubis with a catheter needle, and insert the peritoneal dialysis tube. Inject 1000ml of sterile isotonic saline or Ringer's lactate solution (10～20ml/kg), connect the outer end of the catheter to the lavage fluid bottle during the operation, raise this bottle, and use the force of gravity to infuse the lavage fluid into the abdominal cavity within 15～20 minutes. Then, tilt and shake the patient's abdomen appropriately to the sides, and after 2～3 minutes, place the empty lavage bottle in a position lower than the patient to observe whether there is any blood or bloody fluid refluxing into the bottle.

　　2. Semi-closed abdominal lavage:Make a 3mm skin incision at the same location, puncture the abdominal cavity with a needle with a wire (commonly 18 gauge) and insert the abdominal transparency tube.

　　3. Open abdominal lavage:Make a 3cm skin incision at the same location, incise the peritoneum by 0.5cm, and observe the abdominal cavity after insertion of the tube.

　　Problems existing with abdominal lavage:

　　(1) It is non-specific, and the diagnostic criteria are not uniform. Sometimes, a red blood cell count of (2～5)×10^10/L may already indicate visceral injury.

　　(2) There may be false-negative results, especially when combined with traumatic diaphragmatic hernia and retroperitoneal injury.

　　(3) There may be iatrogenic injuries, accounting for 1%, including injuries to the intestines, bladder, and intraperitoneal blood vessels.

　　(4) The operation is time-consuming and complicated. In recent years, there has been a trend for ultrasound and CT scans to replace abdominal lavage, however, for the purpose of determining whether there is blood accumulation in the abdominal cavity, abdominal puncture remains a quick and simple method.

　　Secondly, X-ray examination:

　　1. Chest X-ray may indicate the possibility of liver trauma in the following situations:

　　(1) The right diaphragm is elevated, and the liver shadow is unclear.

　　(2) There is pleural effusion or right-sided pneumothorax.

　　(3) There is pulmonary contusion in the lower right lung.

　　(4) There is a fracture of the right lower rib.

　　(5) There is fluid or hematoma under the right diaphragm.

　　2. If the following conditions are found in the abdominal flat film, it should be highly suspected that there is liver rupture:

　　(1) The liver shadow is enlarged.

　　(2) The right colonic mesentery is expanded.

　　(3) There is irregular strip shadow in the lateral abdomen.

　　(4) There is fluid retention in the pelvis.

　　(5) There is diffuse shadow in the abdomen.

　　(6) There is a metallic foreign body in the upper right abdomen.

　　Three, B-ultrasound examination:B-ultrasound examination, with its non-invasive, low-cost, convenient operation, and certain specificity, has been listed as the first choice for abdominal closed injuries. The establishment of an emergency room ultrasound machine for emergency room B-ultrasound examination is conducive to repeated examinations for cases with unstable hemodynamics, thus avoiding delaying the rescue time (Table 2).

　　Liver trauma is mainly manifested in ultrasonic images as:

　　1. The continuity of the liver capsule is lost, and the echo at the break is enhanced.

　　2. A non-echoic area or hypoechoic area under the liver capsule or in the liver parenchyma.

　　3. Anechoic area in the abdominal cavity suggests intraperitoneal hemorrhage.

　　The sensitivity of emergency room B-ultrasound examination for abdominal trauma is 81.5%, and the specificity is 99.7%. Shanghai Oriental Hepatobiliary Surgery Hospital conducted emergency room B-ultrasound examination on 26 cases of closed liver trauma, with a correct diagnosis rate of 96.2% (25/26). Only one case of traumatic diaphragmatic hernia caused by the left liver and stomach embedded in the thoracic cavity showed left pleural effusion with inhomogeneous echoes.

　　Four, CT examination:For cases with difficulty in diagnosis and hemodynamic stability, CT examination can show:

　　1. Subcapsular hematoma, the shape of the hematoma is biconcave, the relative density change is higher than that of liver parenchyma, and the CT value can be greater than 70~80HU. It shows a blurred semicircular shadow that separates the liver capsule from the liver parenchyma, forming a separation phenomenon. After several days, the hematoma density decreases and becomes almost equal to the density of the liver parenchyma, with a CT value of about 20~25HU.

　　2. Intraparenchymal hematoma, similar to subcapsular hematoma, there are blurred circular or oval shadows in the liver. The CT value of fresh hematoma is higher than that of liver parenchyma, and it gradually decreases in density.

　　3. True liver rupture, with irregular fissures or defects at the liver margin. Some are irregular linear or circular low-density areas, and some are branched low-density areas, similar to dilated bile ducts. High-density blood clot shadows are often seen within the low-density areas. In recent years, CT examination has important reference value for the judgment of liver trauma, especially for the monitoring and observation of non-surgical treatment.

　　Five, hepatic artery angiography:In addition to the contrast agent leakage from the破裂处 in the liver trauma, there are changes in the shape of the liver, and the intraparenchymal hematoma is manifested as displacement and extrusion of the intraparenchymal vascular branches. The hematoma in the substance phase shows filling defects. Subcapsular hematoma shows separation of the liver parenchyma and capsule, and the liver margin is compressed, flattened, or concave in the substance phase. Selective hepatic artery angiography can not only determine the site of the injury but also inject embolic agents to control bleeding.

　　What kind of food is good for the body after liver trauma

　　Rationally match the diet, eat light food. Cereals such as glutinous rice, black rice, sorghum, and millet; followed by jujube, longan, walnut, chestnut; and meat and fish such as beef, pork stomach, crucian carp, etc., also have a health-preserving effect on the liver. In addition, vegetables such as leek, garlic, onion, mustard, coriander, ginger, and scallion can disperse wind and cold, and kill bacteria.

　　(The above information is for reference only, please consult a doctor for details.)

　　First, treatment

　　The treatment of liver injury should first consider the patient's overall condition and whether there are associated injuries, such as brain, lung, or bone injury. A reasonable treatment plan should be determined based on the overall condition and the severity and urgency of associated injuries. For patients with simple liver injury, surgery should be prepared actively while correcting hemorrhagic shock.

　　1. Emergency treatment:Firstly, keep the respiratory tract unobstructed and provide sufficient oxygen. Rapidly establish two or more venous channels to ensure the smooth flow of blood transfusion and fluid replacement, and avoid insufficient blood perfusion to vital organs. It is recommended to use upper limb venipuncture because the lower limb veins may be occluded during surgery. It is best to have one venous access through percutaneous subclavian vein puncture or internal jugular vein puncture and catheter insertion, with the catheter placed in the right atrium (superior vena cava), which is beneficial for rapid fluid infusion and monitoring central venous pressure (CVP) to regulate fluid volume. Urinary catheters should also be placed to observe urine output per hour. Necessary examinations should be performed when the condition improves and vital signs are stable, and further treatment plans should be made after a clear diagnosis. Severe shock patients can undergo surgery while blood transfusion, fluid replacement, and expansion are being performed. It is not advisable to wait until shock is corrected before dealing with the injury, as this often results in missing the opportunity to save the patient's life.

　　2. Non-surgical treatment:Pachter reported that the success rate of non-surgical treatment for mild liver injury can reach 95% to 97%. The theoretical basis for non-surgical treatment is: ① 86% of liver injuries have stopped bleeding during surgery, and due to anatomical reasons, there are more opportunities for spontaneous hemostasis in the right liver and midline lacerations. 67% of patients with positive peritoneal lavage and exploratory surgery do not require further surgical intervention. ② CT and BUS can accurately judge and dynamically monitor the condition of injury, providing conditions for non-surgical treatment. ③ Non-surgical treatment has fewer impacts, quick recovery, short hospital stay, and is easy for patients to accept.

　　Indications for non-surgical treatment after liver trauma: ① Patients with grade I, II, or III hematomas (AAST classification) without active bleeding, and no progressive expansion of the hematoma. ② Hemodynamic stability with blood loss not exceeding 600ml. ③ Mild symptoms of peritonitis, with patients being conscious and able to cooperate with physical examination. ④ No intra-abdominal associated injuries. Under these circumstances, surgical treatment may be temporarily withheld while monitoring vital signs, hemoglobin, and abdominal circumference dynamically.

　　Patients should rest in bed for more than 2 weeks, be tranquilized and pain relieved, receive blood transfusion and fluid replacement, prevent infection, and use hemostatic drugs correctly. The selection of antibiotics is based on the bacteria that may exist in bile. Hemostatic drugs are used in combination with procoagulants and antifibrinolytic agents, and vasoconstrictors may be used in combination when necessary. Abdominal distension patients can undergo gastrointestinal decompression to promote the recovery of gastrointestinal function and facilitate the absorption of blood in the abdomen. Some patients can undergo selective hepatic artery angiography to find the bleeding focus and then undergo embolization therapy, which is effective.

　　Bedside ultrasound (BUS) monitoring is the most convenient. If the patient shows changes in vital signs or active bleeding in the abdomen exceeding 200ml per hour during monitoring, surgical treatment should be immediately converted. Attention should be paid to the possibility of delayed liver hemorrhage due to subcapsular hematoma.

　　3. Surgical treatment:When liver trauma patients have obvious intra-abdominal hemorrhage, symptoms of peritonitis, or accompanied by concomitant injury of abdominal visceral organs, laparotomy should be performed at the same time as correcting shock. The basic principles of surgery are: ① Stop bleeding; ② Ligate the bile duct; ③ Remove necrotic liver tissue; ④ Drainage; ⑤ Treat concomitant injuries.

　　(1) Surgical exploration: The incision is usually a midline upper abdominal incision, which can be extended to the 7th right intercostal space to form a thoracoabdominal incision if necessary. If the diagnosis of liver injury is very clear, a subcostal incision can be used. The incision should be large, with sufficient exposure, which is conducive to finding the bleeding site.

　　After laparotomy, while aspirating the accumulated blood in the peritoneal cavity, attention should be paid to the source of bleeding. The area with concentrated coagulation clots is often the site of bleeding. If bleeding is profuse and the bleeding site cannot be seen, decisive action should be taken immediately to block the first portal using a wide S-shaped clamp or fingers, and timing should be started. If bleeding is controlled after blocking, it indicates portal vein or hepatic artery bleeding. If there is still severe bleeding, it may indicate injury to the hepatic vein or inferior vena cava, and the bleeding should be quickly stopped by packing the posterior aspect of the liver with gauze rolls. Quickly open the chest through the 7th and 8th intercostal spaces, cut through the diaphragm to the hiatus of the inferior vena cava, and further explore under direct vision. When exploring the second portal and the posterior right lobe of the liver, the liver ligaments should be cut first, and the liver should be fully mobilized. Avoid using hand force to probe before mobilization to avoid exacerbating the injury. When aspirating the coagulation clots below the posterior aspect of the second portal and inferior vena cava, one should be prepared for the possibility of severe bleeding. After bleeding is controlled, explore the site and extent of liver injury, and pay attention to whether there is injury to liver vessels and bile ducts. If the mechanism of injury is gunshot wound, the possibility of vascular and bile duct injury is very high, with reports ranging from 96% to 98%. If the injured vessel cannot be seen clearly, the necrotic liver tissue can be separated to expose the vessel. If necessary, the blocked portal vessels can be released to accurately locate the bleeding site and treat it. After the liver injury is treated, a comprehensive exploration of other abdominal organs should be conducted to avoid missing any injury.

　　The upper limit of the time for portal vein ligation is not yet clear. Delva reported that the thermal ischemia time of normal liver is 90 minutes, but the warm ischemia time of liver trauma is often less than that of normal liver tissue.

　　(2) Autologous blood transfusion: Early in the treatment of patients with traumatic liver rupture, the primary cause of critical condition is excessive blood loss. Whether sufficient whole blood can be transfused is the key to rescue. In the operation, while effectively controlling bleeding, autologous liver blood can be rapidly used for blood volume restoration. Autologous blood transfusion should be禁忌 in the following situations: ① Concomitant injury of abdominal cavity hollow organs; ② Urinary system injury with urine extrusion; ③ Pancreatic injury; ④ Open liver injury; ⑤ Trauma time greater than 8h; ⑥ Large extrahepatic bile duct or gallbladder rupture.

　　Research shows that autologous blood transfusion can reduce the mortality rate by 10.9%. Some people believe that the blood from liver rupture bleeding mixed with bile and necrotic tissue can cause serious complications, such as acute renal failure, if it is reinfused. However, it is currently believed that when hemorrhagic shock occurs, liver blood flow decreases, liver cells become oxygen-deprived, bile secretion decreases, and after being diluted by a large amount of blood, it is not likely to cause side effects. Free blood in the peritoneal cavity will not coagulate after more than 1 hour, and anticoagulants do not need to be added as long as there is no active bleeding during surgery. Otherwise, appropriate anticoagulants should be added. For autologous blood reinfusion, it is necessary to use double gauze filtration. To compensate for the Ca2+ consumed due to massive bleeding, 10ml of 10% calcium gluconate should be infused for every 500ml of blood reinfused.

　　(3) Surgical method:

　　①Simple suture: Suitable for mild liver injury with shallow lacerations and tidy incisions. This method is simple and quick, and can control bleeding and repair the wound in a short period of time. Most wounds can be sutured with intermittent sutures or mattress sutures. The key points of suture are to suture through the bottom of the laceration, leaving no ineffective cavity, and to place drainage routinely. For severe injury, drainage should be placed separately at the suture site and below the diaphragm. For superficial lacerations, electrocoagulation can also be used. If bleeding has stopped, it is not necessary to suture, and appropriate drainage is sufficient. Simple suture often leads to postoperative bile leakage, infection, or biliary hemorrhage in severe liver injury due to deep lacerations, unligated bile ducts and blood vessels within the wound, and unexcised necrotic tissue.

　　②Laparotomy debridement, selective bile duct vessel ligation, and omentum packing and suture: It is suitable for lacerations deeper than 3cm or central-type rupture injuries. If the incision is small and the deep bleeding focus cannot be directly explored, the ends of the incision can be cut with an electric knife to enlarge the wound. Dead liver tissue that has been necrotic and detached can be removed by finger method or handle method to bluntly clear, and the exposed ends of the large blood vessels and bile ducts must be ligated to prevent the formation of intrahepatic abscesses after surgery. The standard for judging viable liver tissue is that fresh blood seeps out from the liver wound surface, and the liver wound surface after debridement should reach: A. No viable liver tissue; B. No oozing; C. No bile leakage. Thorough debridement is a key step in this surgery.

　　If there is still seeping blood from the liver parenchyma, parallel deep mattress sutures can be added to the edge of the liver wound, and a pedicled omentum can be used to pack the remaining cavity and suture the wound surface. Effective and unobstructed drainage should be placed around. The omentum has rich blood supply and strong anti-infection ability, which can eliminate the ineffective cavity when filled into the wound, and direct pressure is conducive to hemostasis. Moreover, the newly formed blood vessels can grow into ischemic liver tissue to promote the healing of liver trauma. This surgical method has definite hemostatic effect and few postoperative complications.

　　It should be avoided to use a large amount of hemostatic agent to pack, as the hemostatic agent is not absorbed and becomes a foreign body, increasing the possibility of infection. Recently, there have been reports that plasma-made coagulation substances can adhere to the wound surface, do not become foreign bodies, and have a good hemostatic effect.

　　③Partial hepatectomy: When severe liver laceration suture and hepatic artery ligation are ineffective, hepatectomy can be considered at an appropriate time in the presence of the following conditions: A. Large pieces of liver tissue are severely fragmented and cannot be repaired. B. The laceration extends to the main blood vessels and bile ducts within the liver. C. Deep penetrating injury of the liver, with difficultly controlled bleeding. D. Severe injury to the left liver lobe or left lateral liver lobe.

　　Although resection of the damaged liver is the most thorough method of hemostasis, the operation for partial liver resection is complex and has a significant impact on the patient. Moreover, the patients are often in a hypovolemic shock state, resulting in a high postoperative mortality rate. It is necessary to strictly control the indications. Traumatic partial liver resection should fully consider the anatomical characteristics of the liver and perform irregular resection, including various subsegmental and transsegmental resections. Often, some methods of hemostasis are needed, such as double-hand pressure, liver tourniquet, liver hemostatic forceps, and portal occlusion. To prevent postoperative liver failure due to excessive liver resection, it is necessary to retain as much normal liver tissue as possible while thoroughly resecting necrotic liver tissue during the operation. Adhere to the principle of 'cut where broken, suture where alive. Resect the non-viable tissue and suture the viable tissue.' Ligate the bile ducts and vessels on the liver wound surface, and after treatment, apply a new saline gauze pad to the liver wound surface to observe for jaundice and bleeding. If the liver wound surface bleeds, argon beam coagulation can be used for hemostasis if conditions permit, or the omentum can be wrapped around it. Generally, double-lumen tubes are used for negative pressure drainage, and the postoperative abdominal drainage tube should be kept unobstructed.

　　④ Gauze packing technique: This technique has a long history and was first reported by Halsted in the early 20th century. Subsequently, it was found that packing materials often lead to fatal infections, and the rate of rebleeding after removal is high, and it was rarely used for a period of time. In 1969, Walt even pointed out that gauze packing has no role in modern liver trauma treatment. However, with the application of highly effective antibiotics in recent years, it has been possible to prevent most fatal infections, and thus gauze packing has gained certain indications: A. For widespread laceration injuries of both liver lobes, it is difficult to control bleeding; B. Extensive subcapsular hematoma under the liver capsule; C. Coagulopathy caused by blood transfusion; D. Hemorrhagic shock that cannot tolerate surgery; E. In remote areas, the conditions for surgery are not mature; F. Patients who need to be transferred to a hospital for treatment after rebleeding after suture.

　　The packing is usually performed by covering the liver wound with a pedicled omentum or a long gauze pad soaked in vaseline, then filling the long gauze pad in an orderly manner from deep to shallow, which can stop bleeding without exerting excessive pressure. Some authors use Steri-Drape, a special plastic rolled cloth for pressure packing, which can prevent the destruction or separation of the liver surface clot during removal and is therefore more effective. Placing packing materials can increase intraperitoneal pressure and stop bleeding and oozing. However, packing is not a definitive treatment measure. Once packing is performed, immediate measures should be taken to correct shock, acidosis, hypothermia, and coagulopathy. Studies have shown that severe injuries with longer surgery times, large amounts of blood transfusions leading to decreased body temperature, acidosis, and coagulopathy, are important causes of death due to their reciprocal and malignant cycle. Therefore, it is advisable to control massive bleeding that threatens the patient's life with simple surgery as soon as possible, to end the operation in the shortest possible time, and to actively expand the blood volume. Once the above conditions improve, a second laparotomy is performed for definitive treatment. This approach is called staged surgery (staged surgery), named damage control (damage control) by Rotondo. Sairi reported that the general condition can be corrected within 18 hours, and a second operation can be performed within 24 hours.

　　The incidence of abdominal abscesses is related to the time of removal of the packing material, 16% for removal within 48 hours; 60% for removal between 4 to 5 days, therefore, early removal of the packing material is wise. Feliciano believes that rebleeding in patients with liver injury is the most dangerous, and incomplete coagulation function in shock patients is more prone to occur. Therefore, the packing material must be placed until the patient's blood pressure is stable and the coagulation mechanism is restored before laparotomy, and most patients can undergo surgery within 3 to 4 days. The operation time should be determined according to the specific situation.

　　⑤ Hepatic artery ligation: There is still bleeding after local suturing or partial liver resection for liver injury, and a decrease in bleeding after blocking the first liver portal indicates that the bleeding mainly comes from the hepatic artery, and hepatic artery ligation can be performed. The following situations can be adopted: A. stellate or central-type rupture injuries; B. deep laceration injuries; C. extensive liver blast injuries; D. extensive subcapsular hematoma under the liver capsule. Since the portal vein accounts for 60% to 70% of the liver blood supply, with high blood oxygen saturation, the liver has extensive collateral circulation. Although there is a temporary ischemia in the liver after hepatic artery ligation, the rapid establishment of collateral circulation does not affect liver function. Selective hepatic artery ligation, which ligates only the left hepatic artery or the right hepatic artery, has a hemostatic effect similar to that of hepatic artery ligation, but has a smaller impact on liver function.

　　The liver has a rich blood supply, and sometimes ligation of the hepatic artery is not sufficient to stop bleeding, and combining it with suture or packing techniques results in better effects. It should be noted that post-ligation of the hepatic artery, gallbladder necrosis can occur, which is related to the blood supply of the hepatic duodenal ligament and the gallbladder bed. Some people advocate that patients undergoing hepatic artery ligation should have the gallbladder routinely removed to prevent ischemic necrosis. For patients with liver cirrhosis or those who have undergone extensive mobilization of the perihepatic ligaments, hepatic artery ligation should be contraindicated.

　　⑥ Liver transplantation: In recent years, with the application of new immunosuppressive drugs, liver transplantation for certain irreversible liver diseases has achieved satisfactory results and has accumulated a large amount of experience. However, whether it can be used for severe liver trauma has aroused people's interest. Patients with extremely severe liver trauma mainly die from hemorrhagic shock and liver function failure, and such patients can still undergo liver transplantation with extremely high risks.

　　Esquivel first reported 2 cases in 1987, followed by subsequent case reports (Angstadt, 1989; Ringe, 1991). Ringe used a two-step method, first removing the injured liver, thoroughly stopping bleeding, and actively expanding volume to correct shock. During the period without a liver, various supportive measures were used to maintain the patient's life, while urgently seeking a donor liver for a second-stage liver transplantation, which was successful. Liver transplantation for liver trauma is mostly an emergency operation, often facing technical and liver supply issues. Currently, there are less than 10 reported cases in the literature, with about 40% of patients surviving after surgery, and it is still difficult to apply it regularly in clinical practice. However, it can be boldly predicted that with the development of transplantation techniques, liver transplantation will be an important method to save patients with extremely severe liver injuries.

　　⑦ Severe injury to major hepatic vessels: Severe injury to major hepatic vessels is rare in clinical practice, but has a high mortality rate, especially injuries to the hepatic veins and inferior vena cava, with a mortality rate exceeding 80%. Most patients die during the journey to the hospital, and another 30% die during surgery, making it one of the most dangerous abdominal injuries. The main causes of death are massive hemorrhage, air embolism, and embolism of liver tissue fragments. Generally, the injured vessels are the hepatic artery, portal vein, hepatic veins, and inferior vena cava.

　　After blocking the first hepatic portal and stopping bleeding, it is mostly due to injuries of the hepatic artery and portal vein. After exploring the wound, minor lacerations can be repaired by suture. For severe injuries, end-to-end anastomosis or autologous or artificial vascular grafting can be performed. For patients with excessive hepatic artery injuries, it is difficult to perform transplantation. If there is no severe liver cirrhosis and the portal vein blood supply is good, hepatic artery ligation can be performed. For patients with excessive portal vein injuries, the distal end of the portal vein can be ligated, and the proximal end can be anastomosed with the inferior vena cava.

　　After blocking the first hepatic portal, if the bleeding from behind or above the liver does not decrease, it is mostly due to injuries of the hepatic veins or inferior vena cava behind the liver. Immediate packing with gauze for hemostasis and ligation of the right liver coronary ligament and triangular ligament to free the right liver lobe should be performed. Expose the lateral margin of the inferior vena cava behind the liver, find the fissure and suture it for repair. When the hepatic veins rupture at the junction with the inferior vena cava or the inferior vena cava below the liver ruptures, repair can be performed under direct vision by opening the diaphragm through a combined thoracoabdominal incision. In the presence of severe right liver lobe injury, liver resection of the right liver lobe can be performed first, directly exposing the right hepatic vein and inferior vena cava behind the liver for repair, but the surgical impact is great and the mortality rate is high. It was previously believed that the hepatic veins could not be ligated, but recent research has found that there are anastomoses in the hepatic veins of normal people. Beppu believes that for single-lateral hepatic vein injuries, if repair is ineffective, ligation can be performed without resection of the corresponding liver segment. After ligation, the pressure in the hepatic veins increases temporarily, but after the communication branches open, the corresponding liver segment can obtain drainage without necrosis. The anatomical position of the hepatic veins or inferior vena cava behind the liver is concealed and surrounded by liver tissue, making it very difficult to expose and suture or repair under direct vision, and the treatment is rather challenging. Even in large trauma centers, the mortality rate is as high as 60% to 100%, with an average of 83%.

　　When bleeding is so severe that packing with gauze is ineffective, total hepatic blood flow occlusion (THVE) at normal temperature can be used, that is, blocking the first liver portal, abdominal aorta, and inferior vena cava above and below the liver, and then performing further treatment after controlling bleeding. There is much controversy about whether to block the abdominal aorta. To reduce blood stasis in the lower body and increase effective blood circulation volume, most people advocate blocking the abdominal aorta. However, some scholars advocate not blocking the abdominal aorta. THVE has the following disadvantages: A. Experiments show that after completely blocking the first liver portal and inferior vena cava, cardiac output decreases, and decreased arterial pressure can cause fatal arrhythmias and cardiac arrest. B. After blocking, the blood perfusion of abdominal visceral organs decreases, and postoperative MODS is prone to occur. C. Patients with hypovolemic shock are difficult to tolerate.

　　Due to the significant pathological and physiological damage caused by total hepatic blood flow occlusion, scholars abroad proposed intracavitary shunting (intracavitary shunting) in the 1970s, which has been widely promoted. There are several types of intracavitary shunting: A. Atrial cavity shunting: that is, first, place a 32F or 34F silicone tube in the inferior vena cava and right atrium, and puncture the right atrium into the renal vein level, or insert the catheter into the right atrium through the inferior vena cava below the kidney. The lateral holes of the catheter are located in the right atrium and the inferior vena cava below the kidney, and the inferior vena cava above the renal vein is tightly ligated with a tourniquet, while blocking the portal of the liver. At this time, both the blood flow of the liver is blocked and the blood return from the lower limb to the heart is maintained. This can fully expose the damaged site for repair. B. Femoral vein balloon catheter shunting: using a 24F or 28F balloon catheter inserted through the femoral vein until the inferior vena cava above the liver, and applying a balloon to isolate the injured inferior vena cava behind the liver. While blocking the blood flow of the liver, it allows the blood from the lower limb to return to the heart. The advantage is that it does not require open chest surgery, but the catheter needs to be directly inserted through the femoral vein, and complications such as venous thrombosis may occur after surgery. C. Inferior vena cava balloon catheter shunting: incise the inferior vena cava below the renal vein level, and insert the balloon catheter upwards to the level above the diaphragm. Inject air or water into the balloon, tightly ligate the inferior vena cava above the renal vein level with a tourniquet, and block the portal of the liver. The purpose of these methods is to control bleeding first, debride the liver injury, and repair the damaged blood vessels under direct vision. Generally, there are the following methods: suture repair, patch repair, end-to-end anastomosis, and vascular grafting. The surgery has a large trauma and complex operation, and the actual effect is not ideal, and many patients die during surgery. Some authors believe that there are certain disadvantages to this operation, but it can still be used for packing hemostasis and direct repair failure. The key to surgical success is: A. The patient is young and strong; B. Once the injury is diagnosed, early surgery should be performed while correcting shock; C. The shorter the shock period, the better; D. There should be a fixed liver trauma treatment team.

　　In summary, liver large vessel injury is a critical condition with difficult treatment and a high mortality rate. Active treatment before admission and correction of shock are very important. In recent years, surgical treatment tends to be direct suture repair or staged treatment, and endoscopic shunt surgery still needs to accumulate experience.

　　(4) Postoperative management: Postoperative liver injury does not mean the end of the rescue work, but the beginning of systemic treatment. Because of the trauma, blood loss, and surgery, the body is in a state of stress. If not corrected in time after surgery, various complications may occur, and the condition of the injury may worsen further. The following points should be done after surgery:

　　① ICU ward monitoring: Continuously monitor T, P, R, BP, urine volume, and if possible, monitor CVP and pulmonary artery wedge pressure. Pay attention to the correction of shock. After being discharged from the ICU, the patient should be admitted to a ward close to the nursing station.

　　② Correct fluid balance and electrolyte disturbance, maintain acid-base balance, and pay attention to strengthen nutritional support.

　　③ Correct anemia and infuse fresh plasma. After liver trauma, coagulation factors, coagulation factors, fibrinogen, and platelets all decrease, so routine use of hemostatic agents such as vitamin K and aminocaproic acid is required.

　　④ Pay attention to protect the heart, brain, lungs, kidneys, and digestive tract function, and prevent the occurrence of MSOF.

　　⑤ Use an adequate amount of antibiotics.

　　⑥ Keep the drainage tube unobstructed, observe the nature and color of the drainage material, and measure it.

　　⑦ Pay attention to the prevention and treatment of complications.

　　4. Laparoscopic treatment:Since the first laparoscopic cholecystectomy was completed in France in 1987, laparoscopic technology has been rapidly applied in other fields of abdominal surgery. In recent years, it has been applied in the diagnosis and treatment of abdominal closed injuries and has achieved good results. In 1994, Sun Zhihong and others reported a successful laparoscopic repair of a grade Ⅲ liver parenchymal laceration (Zhongshan Zhi Ming classification).

　　Laparoscopic direct visualization can not only clarify the location and extent of the injury, but also see whether the injured organ is still actively bleeding. In this way, those with stopped bleeding can be identified according to the characteristic manifestations under laparoscopy, such as clear linear or star-shaped lacerations on the diaphragmatic surface of the liver, and lacerations of the falciform ligament and the round ligament of the liver. Those without injury can use a retractor to lift the right lobe of the liver to observe the visceral surface and whether there is bleeding behind the liver. A 30-50 degree laparoscope is more convenient for observation. After removing the accumulated blood, the wound is flushed with cold saline, and bleeding from the wound is stopped by electrocoagulation, or by argon beam electrotome. It is also possible to use gauze to compress and stop bleeding first, and then remove the gauze while coagulating. The application of hemostatic agents such as absorbable gelatin sponge and fibrin glue is also very effective. For those with mild lacerations (liver injury level Ⅰ, Ⅱ, AATT classification), liver rupture repair surgery can also be considered. If the liver injury is found to be severe, bleeding is severe, hemodynamics is unstable, or it is difficult to handle, or there are other conditions requiring laparotomy surgery, an immediate laparotomy should be performed, and safety should be given top priority without any侥幸心理. The size, location, and extent of the surgical incision can be determined based on the information provided by the laparoscopic observation.

　　There are also many disadvantages to laparoscopic examination. Television laparoscopic exploration requires a large amount of equipment. The preoperative preparation time is generally longer than that of laparotomy, and it also takes time to create pneumoperitoneum. The speed of clearing blood during surgery is not as fast as that of laparotomy. For severe visceral injuries with rapid bleeding or major vascular injuries, although laparoscopy can be used for diagnosis, it cannot stop bleeding quickly and thoroughly. Vascular injuries can lead to air embolism, and diaphragmatic injuries can lead to tension pneumothorax. Moreover, during surgery, one can only observe the surface of the liver and cannot touch it directly with hands, nor can one examine the intestines segment by segment.

　　Laparoscopy has both diagnostic and therapeutic functions, and due to its small trauma and rapid recovery, it is more in line with the requirements of surgery and will undoubtedly become a trend in future surgical treatment.

　　5. Treatment of late liver injury:Late liver injury refers to liver injury that has been initially treated surgically, but due to improper treatment or because of the severity and complexity of the injury, it needs to be transferred to a higher-level hospital for further definitive treatment. The diagnosis and re-treatment of such patients are quite challenging. The following discussion from the perspective of clinical treatment divides the main problems that may exist in patients according to the time of transfer into three groups.

　　(1) Early casualties: Early casualties refer to those who are transferred within 24 to 48 hours after the injury, mainly due to improper initial treatment and continued bleeding issues.

　　①Improper initial treatment: This group of patients often undergoes the first laparotomy due to the lack of experience of surgeons in dealing with liver trauma for intra-abdominal hemorrhage, and the abdomen is closed after being packed with gauze. In fact, this may also be the safest measure, because more dissection and division of the perihepatic ligaments may cause rebleeding or cannot be packed effectively with gauze to stop the bleeding. Once the operation is completed, the patient should be transferred to a hospital for treatment as soon as possible, otherwise it may endanger the patient's life. In some cases, it is possible to contact the trauma treatment center by phone to inquire about the methods of dealing with problems during surgery. The most important thing is to differentiate between arterial and venous bleeding. If the Pringle maneuver can reduce bleeding, then the bleeding may come from the branches of the hepatic artery and portal vein. When the bleeding is mainly arterial, the hepatic artery supplying blood to the lobe of the lacerated liver should be ligated, and then the omentum should be packed in. Sometimes, this can achieve better results, and gauze can also be added outside the liver capsule. After the operation is completed, the patient should be transferred to a hospital as soon as possible. After being sent to the trauma treatment center, the gauze can be removed 36 to 48 hours after the injury. All preparations should be made in the operating room for the patient's laparotomy and liver resection. The gauze should be gently removed under light general anesthesia. If there is rebleeding, a prompt laparotomy should be performed for definitive surgical treatment.

　　② Continuous bleeding: After the injured patient is transferred to the trauma treatment center, the first thing is to obtain information about the first operation from the doctor responsible for the patient's treatment, so as to formulate a plan for whether surgical treatment is needed. Early referral patients generally do not require special examinations. Some patients, although treated appropriately by surgery, still have signs of continued bleeding. Therefore, it is necessary to check the coagulation function and correct it in a timely manner. If the initial surgical treatment is inappropriate and there is still continued bleeding, it is often due to the doctor underestimating the severity of the injury or not considering the possible injury to the inferior vena cava or hepatic veins, and it is impossible to correctly estimate the severity of liver injury unless the perihepatic ligaments are completely freed. For deep liver lacerations, simply suturing the peritoneum will not control arterial bleeding. Continued bleeding from the deep laceration will further damage the liver substance, and in the end, blood will still leak out from the sutured fissure. Due to changes in the condition, reoperation may be required. Even if bleeding stops after packing the laceration, late complications such as abscess formation, secondary bleeding, and occasional biliary bleeding may occur. During reoperation, the liver must be completely freed before a correct evaluation of liver injury can be made. In surgery, it is necessary to remove necrotic liver tissue, and if possible, directly ligate the bleeding vessels, cut the liver tissue crossing the wound, fully expose the deep part of the liver laceration, open the wound like a book, clamp the hepatoduodenal ligament to block the first hepatic portal, and then suture the wound under controlled bleeding conditions more accurately. The safe ischemic time for human liver heat can exceed 20 minutes. There are reports that the blocking time can reach more than 64 minutes and still recover smoothly. If direct suturing cannot control arterial bleeding, it is possible to ligate a branch of the hepatic artery, which is a safe and reliable method. If combined with the use of pedicled omental patch packing, it can often compress venous bleeding from the liver substance.

　　During reoperation, if the first hepatic portal cannot control bleeding even after ligation, it should be considered that there may be injuries to the inferior vena cava and hepatic veins. At this time, the intercostal space or the sternum should be split upwards to fully expose the surgical field, then the perihepatic ligaments should be cut. If it is a small fissure in the hepatic or inferior vena cava, the liver can be flipped until the entire fissure is sutured to stop bleeding. Sometimes, debridement and excision surgery is needed to see the fissure. If the hepatic vein is completely ruptured, due to the lack of venous blood return pathway, hepatectomy is required. For severe injuries to the inferior vena cava, intracorporeal shunting techniques should be used to block the blood flow of the entire liver, including blocking the superior and inferior vena cava and inserting internal shunting tubes to ensure venous blood return, and repairing the inferior vena cava under relatively bloodless conditions. Such injuries to the inferior vena cava have a very high mortality rate. There are also certain difficulties in the operation of various internal shunting methods.

　　Gauze packing is simple but can sometimes save the patient's life. Its advantages are: A. It can temporarily control bleeding, allowing for referral to a hospital or specialized center with complete conditions for treatment; B. After a large amount of blood transfusion, there is often a combination of hypothermia and acidosis, and for those with coagulation dysfunction, gauze packing is used to stop bleeding to gain time; C. When there is persistent oozing after the definitive surgery is nearly completed, gauze packing can control bleeding and save more blood. The method of gauze packing is to stuff a roll of gauze or gauze strips into the liver fissure, but it can also be separated from the wound surface first with a pedicle omentum flap. Then, apply broad-spectrum antibiotics, and quickly refer to a specialized hospital or treatment center. Calne (1982) reported 26 cases of liver injury, of which 11 were severe liver lacerations, and 7 were treated only with gauze packing. After removing the gauze, 3 cases healed spontaneously, and the remaining 4 cases had 3 survivors, 2 underwent hepatectomy, and 1 had hematoma drainage. In recent years, there have been more reports of successful gauze packing in cases with severe coagulation dysfunction. Syoboda et al. (1982) reported 10 cases in which gauze packing was used to correct the blood coagulation disorder, and the definitive liver surgery was successfully completed 24 hours later. Feliciano et al. (1981) reported 10 cases with severe oozing after definitive liver surgery, all of whom survived after gauze packing.

　　(2) Intermediate-term injured personnel: Intermediate-term injured personnel generally refer to those referred due to multiple organ failure and subcapsular hematoma 3 to 7 days after injury.

　　①Multiple Organ Failure: The bleeding caused by liver injury in the first operation of this group of patients has been controlled, but the patients still have severe head, chest, or limb injuries. After referral, there are often shock, pulmonary and renal function failure, so the mortality rate of this group of cases is very high. Even if the patients have no obvious specific complications, they still need close monitoring and further treatment, mainly to carefully check for any unprocessed intrahepatic or perihilar infections, as well as complications affecting the lungs or kidneys. It is best to discuss the findings of laparotomy with the physician who performed the first operation. Physical examination may not be very helpful, but it is necessary to record the nature and quantity of the drained fluid in detail. Ultrasound examination of liver injury and its surrounding tissues is often meaningful and helpful in solving the problem of liver injury. Sometimes, liver angiography can prove the presence of necrotic tissue areas within the liver. If due to jaundice deepening and a large amount of bile drainage, it should be suspected that there is biliary obstruction or injury, and sometimes it is necessary to perform endoscopic retrograde cholangiopancreatography (ERCP) examination.

　　②Subcapsular hematoma of the liver: In some cases, immediate laparotomy was not performed due to the absence of positive signs after injury, and these patients were transferred for further treatment. Such patients can be easily diagnosed with subcapsular or intraparenchymal hematoma using ultrasound. Therefore, ultrasound can be used to monitor the development of the hematoma. If conservative treatment is to be carried out, it should be done cautiously, as it may sometimes overlook severe duodenal and colonic injuries. The consequences of subcapsular hematoma of the liver are difficult to predict, and sometimes this type of injury may heal naturally, but some patients may require laparotomy several days later. Some hematomas may liquefy or continue to expand, causing pain or tenderness. Laparotomy usually does not find active bleeding, and only the liquefied hematoma needs to be removed.

　　(3) Late-stage injured patients: Late-stage injured patients refer to those who have been transferred more than one week. Although chest infections are common, they are mainly related complications of the liver injury itself. Common complications include infection, sepsis, jaundice, malnutrition, and bile fistula; less common complications include gastrointestinal bleeding, secondary bleeding from the drainage tube, and functional duodenal obstruction, among others.

　　①Disease judgment: For patients with multiple injuries requiring surgery, it is necessary to obtain information about the findings and the type of surgery performed during the operation from the surgeon first, and then to review the relevant examination records of each system, including clinical, biochemical, and X-ray examination results. In fact, the clinical findings often underestimate the severity of liver injury, and the medical history often has records of relatively firm peritoneal suture, however, there may still be hemorrhagic bleeding from the hepatic artery in the deep liver tissue, further destroying the liver parenchyma, causing the original mild or moderate liver injury to become severe liver injury, even threatening the patient's life. After understanding the medical history, it is necessary to check for other associated injuries, and to perform pulmonary function tests, sputum culture, X-ray films, and blood gas analysis, among other tests. The abdomen should be examined carefully, with attention to the nature of the wound and drainage material. The following four most meaningful examinations can be performed to judge the liver injury itself: A. Ultrasound examination to check for intrahepatic or peripheric abscesses, and whether the intrahepatic bile ducts are dilated; B. Selective angiography to check for necrotic liver tissue, which can be combined with ultrasound results to determine whether emergency debridement is needed to control infection and sepsis; C. Radionuclide scanning (HIDA) to confirm the patency of the biliary system, where normal subjects show rapid excretion of radionuclide substances from the entire liver to the intestines; D. Endoscopic retrograde cholangiopancreatography (ERCP), especially necessary for patients with bile fistula, to confirm the integrity of the biliary system, and sometimes it can be simpler to inject contrast material into the fistula of the bile fistula. Antibiotic treatment should be given simultaneously with these examinations.

　　②Treatment:

　　A、Nutritional support: Due to these patients being in a severe catabolic state due to widespread trauma and infection, enteral nutrition can be administered through nasogastric feeding if gastrointestinal function is good; otherwise, intravenous nutrition should be used.

　　B、Infection: The most common problem in this group of patients is sepsis. If there is persistent tubular necrosis, there is a high suspicion of abdominal and extraperitoneal surgical complications. It is impossible to recover renal function without resolving the intra-abdominal infection. B-ultrasound and angiography can confirm the presence of infection around the liver, inside the liver, or related to necrotic liver tissue. Reoperation can be performed for sufficient drainage of abscesses around the liver. Sometimes, small compartments of cholestatic peritonitis have formed in the upper abdomen, so these compartments need to be opened during exploration, and peritoneal lavage should be performed. Two drainage tubes can also be placed above the colon for cross lavage for 24 to 36 hours to remove necrotic tissue. If there is a large amount of fluid under the liver capsule, double-tube cross lavage should be performed to remove necrotic and non-viable liver tissue, and a pedicled omental flap can be placed in the cavity with larger defects to accelerate control of infection. At this stage of liver injury, most of the necrotic liver tissue has liquefied, so liver resection is no longer performed. However, if it is solid necrotic liver tissue, resection may offer a chance for survival. Whether to perform typical lobectomy or debridement liver resection depends on the results of angiography and findings during surgery. Although liver resection in this situation has a high mortality rate, it is difficult to control sepsis if there is necrotic liver tissue.

　　C、Jaundice: Jaundice is relatively common after liver trauma, most of which is caused by sepsis or infection. Once the infection is controlled, jaundice can regress spontaneously. If bile duct injury is found during surgery, bile duct repair can be performed, and a T-tube can be placed as internal support, and postoperative bile ductography can exclude mechanical obstruction. If ultrasound cannot exclude mechanical obstruction and the bile duct has not been explored, ERCP examination is needed to determine the cause and location of the obstruction.

　　D、Biliary fistula: Biliary fistula is a serious injury and necrosis in the central area of the liver, forming an abscess and flowing out liquefied liver tissue or pus and bile from the drainage tube. If there is no biliary obstruction, biliary fistula will heal spontaneously after the infection is controlled. However, if the biliary fistula persists, it should be confirmed whether there is biliary obstruction by inserting a ureter into the biliary fistula for biliary angiography or performing ERCP examination. Central liver injury may affect the left and right hepatic ducts or common hepatic duct, forming persistent biliary fistulas. These patients are not suitable for early liver exploration, as adhesions and proliferative granulation tissue may seal the normal anatomical structures, making surgery difficult to perform. If there is no biliary obstruction at the distal end, biliary fistula will heal spontaneously.

　　E, Gastrointestinal hemorrhage: This can be seen in critically ill patients with any severe trauma. Even with the routine use of alkaline drugs and H2 receptor antagonists, bleeding can still occur due to erosion of the gastric and duodenal mucosa. Endoscopic examination is easy to make a diagnosis, and conservative treatment is generally adopted. If bleeding is severe, surgery can be performed, but the mortality rate is very high.

　　Only a small number of patients experience biliary hemorrhage after liver injury. These patients often have a history of tight liver capsule suture, and initial recovery is good. However, after a period of time, intermittent biliary hemorrhage occurs. Endoscopic examination is normal, but a history of trauma can suggest the diagnosis of biliary hemorrhage. Selective angiography often shows areas of liver parenchymal damage, and sometimes extravasation of contrast agent can be seen, indicating the location of active hemorrhage, and arterial embolization treatment can be chosen. Now, it is rarely used to ligate the hepatic artery or perform liver resection. There are reports of gallstones forming due to blood as the core after biliary hemorrhage.

　　F, Secondary hemorrhage: Sometimes, patients with intrahepatic infection can naturally occur or secondary hemorrhage can occur due to debridement. The surgical treatment for such patients is somewhat difficult, and sometimes liver resection may be required. However, for critically ill patients, selective arterial embolization treatment can be chosen through femoral artery catheterization.

　　II. Prognosis

　　In general, the mortality rate of simple liver trauma and open liver trauma is relatively low, while the mortality rate of complex liver trauma and closed liver trauma is relatively high. Severe liver trauma often involves injury to other organs. Due to massive bleeding after injury, prolonged shock, the impact of surgery, or the occurrence of postoperative complications, liver and kidney function failure and multiple organ dysfunction syndrome can occur. Once it occurs, it is very difficult to treat, and the mortality rate can reach over 70%. Therefore, for patients with liver trauma, the following should be done: ① Timely first aid, resuscitation, and anti-shock treatment after injury; ② Correctly treat the liver wound surface with hemostasis as the center; ③ Actively treat associated injuries; ④ Strengthen treatment under ICU supervision after surgery.