Acute liver failure

　　1. Viral hepatitis (type A, B, C, etc.): Viral hepatitis is a group of infectious diseases caused by several different hepatotropic viruses (hepatitis viruses), mainly characterized by liver inflammation and necrotic lesions. It is a class B notifiable disease with strong infectivity, complex transmission routes, widespread prevalence, and high incidence. Some patients with hepatitis B, C, and D can develop into chronic hepatitis, and may progress to liver cirrhosis and primary liver cell carcinoma, posing a great threat to public health. Up to now, five types of viral hepatitis have been confirmed, including types A, B, C, D, and E, among which types A and E mainly manifest as acute hepatitis. Types B, C, and D can present as either acute hepatitis or chronic hepatitis, and there is a possibility of developing liver cirrhosis and liver cell carcinoma.

　　2. Chemical poisoning: Acetaminophen, methyldopa, isoniazid, rifampicin, pyrazinamide, rifampicin, halothane, carbon tetrachloride, salicylic acid, phosphorus, etc., may cause acute liver failure.

　　3. Surgical diseases: Acute liver failure may occur in patients with surgery, trauma, shock, etc., often with pre-existing liver cirrhosis, obstructive jaundice, and other liver dysfunction.

　　4. Other: Acute liver failure can also occur during pregnancy (usually in the last three months) and Wilson's disease, etc.

　　(1) Hepatic encephalopathy: During hepatic failure, due to the comprehensive impairment of liver function, a syndrome of varying degrees of neurological dysfunction can occur, mainly manifested as disturbance of consciousness, abnormal behavior, and coma, which can ultimately lead to death.

　　(2) Disruption of water, electrolyte, and acid-base balance: Due to severe gastrointestinal symptoms in patients and the use of diuretics, hyponatremia, hypokalemia, hyperkalemia, and acid-base imbalance may occur.

　　(3) Renal insufficiency: Due to insufficient effective circulating blood volume and the effects of endotoxins, functional renal insufficiency can occur. If not corrected promptly and effectively, it can further lead to organic renal insufficiency and ultimately renal failure.

　　(4) Severe hospital-acquired infections: Due to the low immune function of the patient's body, imbalance of intestinal microecology, reduced function of the intestinal mucosal barrier, and a large number of invasive operations, various hospital-acquired infections may occur during hospitalization, aggravating the condition, including various fungi and bacteria.

　　(5) Various bleeding caused by coagulation energy disorders: such as nosebleeds, mucosal ecchymosis, or even internal bleeding.

　　(6) Abnormal glucose metabolism: Due to poor appetite and metabolic disorders of glucose by the liver, severe hypoglycemia may occur.

　　1. Hepatic encephalopathy: This disease is mainly a central nervous system dysfunction characterized by disturbance of consciousness. The most fundamental cause is acute liver failure or portosystemic shunt, which prevents toxic substances from the intestines from being detoxified or cleared by the liver, or from entering the systemic circulation directly through collateral circulation around the liver, passing through the blood-brain barrier to the brain tissue, causing cerebral dysfunction. It often occurs on the basis of acute liver failure, liver cirrhosis, spontaneous or artificial portosystemic shunt, and can also occur on the basis of primary liver cancer, acute fatty liver of pregnancy, and severe biliary tract infection.

　　2. Jaundice: Also known as jaundice, commonly known as yellow disease, it is a symptom and sign caused by the increase of bilirubin in serum, leading to yellowing of the skin, mucous membranes, and sclera. Certain liver diseases, gallbladder diseases, and blood diseases often cause the symptoms of jaundice.

　　3. Liver odor: When the patient breathes out, or when observing the patient's urine, if a mixed smell of rotten apples and臭 eggs or a fishy smell with a sweet aroma is detected, it is liver odor. Liver odor is a characteristic of severe liver disease patients, especially liver coma patients, during liver failure.

　　4. Bleeding: Skin hemorrhagic spots, bleeding at injection sites, or gastrointestinal bleeding may occur.

　　5. Complications of other organ system dysfunction: Commonly, it is the reduction of renal function, decreased urine output, even acute functional failure. Blood pressure tends to decrease, which is related to the reduction of peripheral vascular resistance or insufficient blood volume.

　　Change clothes according to the change of weather to prevent catching a cold; get vaccinated in time to prevent the invasion of various viruses and bacteria. In summer, when it is hot, if hepatitis patients are infected with other viruses or bacteria, it often leads to the occurrence of acute liver failure.

　　Drink in moderation to prevent intoxication and alcoholism. Drinking a large amount of alcohol in a short period of time can lead to acute alcoholic hepatitis, while long-term excessive drinking can lead to chronic hepatitis or fatty liver; under the stimulation of alcohol for a long time, acute liver failure patients are prone to develop alcoholic cirrhosis.

　　Develop good eating habits and pay attention to balanced diet. Acute liver failure patients must strictly avoid raw seafood and meat in summer to prevent the occurrence of new infectious diseases. Balanced diet specifically includes the following contents: consume an appropriate amount of protein, fat, and carbohydrates every day; the daily diet should be balanced and not偏食; the daily diet should mainly include milk, eggs, lean meat, fruits, various bean products, and green vegetables.

　　(One) Coagulation factors

　　The prothrombin time (PT) prolongs in ALF and cannot be corrected with vitamin K. If the PT time in the first phase is greater than 50 seconds, it indicates a poor prognosis.

　　(Two) Serum total bilirubin and direct bilirubin

　　Progressive elevation suggests a poor prognosis.

　　(Three) Transaminases (ALT and AST)

　　It can be abnormally elevated in ALF, reaching thousands. Dynamic observation has certain reference value for prognosis.

　　(Four) Blood glucose measurement

　　If it is below normal, it should be corrected immediately.

　　(Five) Alpha-fetoprotein (AFP)

　　Elevated AFP indicates active liver cell regeneration and usually indicates a good prognosis.

　　(Six) Blood urea nitrogen and creatinine

　　Increased in liver-kidney syndrome.

　　(Seven) Electrolytes, blood gas, and acid-base balance

　　Detection should be carried out regularly, and any abnormalities should be corrected promptly.

　　(Eight) Diffuse intravascular coagulation (DIC) indicators

　　For those with bleeding or a tendency to bleed, regular detection should be performed.

　　(Nine) Central venous pressure

　　The normal value is 50-120 mmH2O, if higher than the normal value, it indicates excess volume or heart failure; if lower than 30 mmH2O, it indicates severe insufficient blood volume, and rapid supplementation is required. In patients with ALF accompanied by hypotension or oliguria, central venous pressure should be measured to determine the volume and speed of fluid resuscitation.

　　(Ten) Intracranial pressure measurement

　　Subdural and epidural transducers are placed to detect, as there is a certain degree of risk, so the gains and losses should be weighed when performing this examination. Generally, the intracranial pressure should be maintained below 2.66 kPa (20 mmHg), and if it is higher than this value, mannitol or thiopental sodium should be administered. If the intracranial pressure is above 5.32 kPa (40 mmHg), liver transplantation cannot be performed.

　　(Eleven) Electroencephalogram (EEG)

　　Normal people have alpha waves of 8-13 times per second, while acute liver failure is characterized by low-amplitude delta waves, 4 times per second, and the amplitude decreases gradually with the progression of brain disease. The worsening of EEG abnormalities often leads to sudden clinical deterioration, which, if the hypoglycemia factor can be ruled out, is usually due to increased intracranial pressure or brain edema, and should be treated promptly.

　　(Twelve) Hepatic histology examination

　　Due to the severity of the condition, there is often a coagulation dysfunction, and liver biopsy carries a high risk, which cannot be accepted by the patient or the physician.

　　Maintain a balanced diet, with staple food as the main component, and eat more vegetables and fruits.

　　Do not eat unclean food, especially moldy peanuts and unfermented sauerkraut.

　　Eat less animal oil and fatty meat.

　　Do not drink alcohol excessively and do not drink alcohol on an empty stomach, as drinking alcohol on an empty stomach is more likely to absorb acetaldehyde.

　　Do not eat food that directly contacts the charcoal fire when having barbecue, as it contains more carcinogens than electric barbecue and iron plate barbecue.

　　6. Salted food is prone to microbial contamination and can damage the liver. It is appropriate to supplement B vitamins and minerals, such as cereal foods.

　　7. Pay attention to dietary restrictions: Foods such as crabs, animal organs, and various seafood (such as yellow croaker, cuttlefish, etc.) should not be eaten. Nutritious foods suitable for liver patients include freshwater fish and soy products.

　　(1) Coagulation Disorders

　　During acute liver failure, the liver produces less coagulation factors, and combined with the decrease in platelets, it can cause bleeding in various parts, especially gastrointestinal bleeding and intracranial hemorrhage, which are often fatal. Gastrointestinal bleeding can be caused by coagulation disorders and stress ulcers. Patients can be placed on a nasogastric tube to detect upper gastrointestinal bleeding and monitor the pH of gastric juice early. When bleeding occurs, local lavage and hemostasis can be performed with ice water mixed with vasoconstrictor drugs. To prevent bleeding, H2 receptor antagonists or proton pump inhibitors can be used, and sucralfate preparations can also be applied. Vitamin K can be injected subcutaneously to correct coagulation disorders caused by a lack of vitamin K; fresh plasma can be used to supplement coagulation factors, and it should be used with caution for those without bleeding, as it can normalize the prothrombin time measurement and thus mask the estimate of prognosis.

　　(2) Hypoglycemia

　　Patients with acute liver failure often have hypoglycemia and should regularly monitor blood sugar changes. When hypoglycemia occurs, 40ml of 50% glucose can be injected intravenously first, followed by continuous intravenous infusion of 10% glucose solution.

　　(3) Brain Disease and Cerebral Edema

　　Treatment for cerebral edema can be done with dehydration therapy, generally using 250ml of 20% mannitol for rapid intravenous infusion (completed in 20-30 minutes), which can be used 3-4 times a day, depending on the condition. About 60% of patients respond to mannitol, but this drug can cause kidney damage and must be closely monitored. Another effective drug for treating cerebral edema is thiopental (Thiopental) for intravenous injection (100mg intravenous injection, once every 15 minutes, and then changed to 1mg/kg.h intravenous infusion after one hour), with efficacy similar to mannitol. The advantage of thiopental is its rapid onset of action and its use is also possible for those with kidney damage, but the disadvantage is that it can cause hypotension and can mask signs of improvement or deterioration of the nervous system. Therefore, mannitol is generally used as the first-line medication, and thiopental is used for those with kidney damage.