Upper gastrointestinal bleeding

　　The causes of upper gastrointestinal bleeding usually include bleeding caused by ulcers and mucosal erosion in the esophagus, stomach, and duodenum, accounting for 55% to 74%; bleeding caused by esophageal varices rupture, accounting for 5% to 14%; Mallory-Weiss syndrome caused by esophageal mucosal tearing, accounting for 2% to 7%; vascular lesions, accounting for 2% to 3%; tumors, accounting for 2% to 5%. In recent years, there has also been an increase in cases of acute hemorrhagic gastritis and erosive gastritis with bleeding, with about 5% of cases where the bleeding focus cannot be determined, even after laparotomy, the cause of bleeding cannot be found.

　　Upper gastrointestinal bleeding can lead to complications such as hemorrhagic shock, secondary peritonitis, and asphyxia.

　　1. Secondary peritonitis (secondary peritonitis) is an acute suppurative peritonitis caused by inflammation, perforation, trauma, hemodynamic disorders, and iatrogenic trauma of abdominal organs, which is a severe peritoneal cavity infection. If it is not diagnosed and treated early, the mortality rate is extremely high.

　　2. Hemorrhagic shock (hemorrhagic shock) is caused by massive blood loss, and whether a shock occurs after bleeding not only depends on the amount of blood loss but also on the speed of blood loss. Shock often occurs when there is rapid and massive (more than 30-35% of total blood volume) blood loss without timely supplementation.

　　3. Asphyxia: The pathological condition called asphyxia is characterized by tissue cell metabolic disorders, functional disturbances, and morphological structural damage caused by hypoxia of various organs and tissues in the human body due to obstruction or abnormality in the respiratory process for some reason, resulting in retention of carbon dioxide.

　　The clinical manifestations of gastrointestinal bleeding depend on the nature, location, amount, and speed of bleeding, as well as the patient's age, renal and cardiac function, and other systemic conditions. Acute massive bleeding is usually manifested as hematemesis; chronic small amount of bleeding is characterized by positive occult blood in feces; when the bleeding site is above the Treitz ligament in the jejunum, the clinical manifestation is hematemesis. If the blood remains in the stomach for a long time after bleeding, it turns into acidic hemoglobin due to the action of gastric acid and appears as coffee-colored. If the bleeding is fast and the amount is large, the color of the vomit is bright red. Black stools or tarry stools indicate that the bleeding site is in the upper gastrointestinal tract, but if the bleeding speed is too fast in the duodenal lesion, the stool color may turn purple due to short停留 time in the intestines. When bleeding occurs in the right half of the colon, the stool color is bright red. In cases of minor hemorrhagic exudation caused by lesions in the jejunum, ileum, and right half of the colon, black stools may also occur.

　　Massive upper gastrointestinal bleeding can lead to acute peripheral circulatory failure. When the amount of blood loss is large and bleeding does not stop or treatment is not timely, it can cause a decrease in tissue blood perfusion and cell hypoxia in the body. Subsequently, due to hypoxia, metabolic acidosis, and the accumulation of metabolic products, peripheral vascular dilation, widespread damage to capillaries, and a large amount of body fluid congestion in the abdominal cavity, bones, and surrounding tissues, resulting in a sharp decrease in effective blood volume, seriously affecting the blood supply to the heart, brain, and kidneys, eventually forming an irreversible shock, leading to death. During the development of peripheral circulatory failure around bleeding, clinical symptoms such as dizziness, palpitations, nausea, thirst, blackouts, or fainting may occur; the skin may appear pale and moist due to vasoconstriction and insufficient blood perfusion; pressing on the nail bed will show pallor, and it may not recover for a long time. The venous filling is poor, and the superficial veins are often sunken. Patients may feel fatigue and weakness, and may further develop symptoms such as mental depression, restlessness, and even dullness of reaction and confusion. Elderly patients with low organ reserve function, combined with common elderly diseases such as cerebral arteriosclerosis, hypertension, coronary heart disease, chronic bronchitis, etc., even if the amount of bleeding is not large, can cause multiple organ dysfunction, increasing the risk of death.

　　10. Treatment of the primary disease should be actively carried out under the guidance of a doctor, such as peptic ulcer and liver cirrhosis.

　　9. Live a regular life. Have regular and moderate meals, avoid overeating, and avoid alcohol, smoking, strong tea, and coffee.

　　8. Pay attention to the use of medication, try to use as few or no drugs that irritate the stomach as possible. If necessary, add drugs to maintain the integrity of the gastric mucosa.

　　7. Regular physical examinations should be conducted to detect early lesions and receive timely treatment. When symptoms of anemia such as dizziness appear, one should go to the hospital as soon as possible for examination.

　　First, laboratory examination:

　　When acute gastrointestinal bleeding occurs, the key tests should include blood routine, blood type, coagulation time, occult blood test in feces or vomiting (radioisotope or immunological occult blood test can be performed if conditions permit), liver function, and blood creatinine, blood urea nitrogen, etc. If conditions permit, blood cell sedimentation rate should be measured.

　　Second, special examination methods:

　　Endoscopic examination is a safe and reliable diagnostic method for acute upper gastrointestinal bleeding, currently the first choice. Its diagnostic value is higher than that of X-ray barium examination, with a positive rate generally reaching 80% to 90% or more. For conditions such as esophageal mucosal tear, erosive gastritis, superficial ulcers that are difficult to detect by X-ray barium examination, endoscopy can quickly make a diagnosis. It is difficult to determine whether the lesions found by X-ray examination (especially when there are two lesions) are the cause of bleeding, while the direct observation by gastroscopy can determine this, and appropriate hemostatic treatment can be performed according to the condition of the lesions. The following points should be noted when performing fiberoptic gastroscopy:
　　1. The best time for gastroscopy is within 24-48 hours after bleeding. If there is a delay in time, some superficial mucosal lesions may partially or completely heal, which will greatly reduce the positive rate of diagnosis. A report from China on a group of 904 cases of upper gastrointestinal bleeding showed that 77% of patients found bleeding sites within 24 hours, 57.6% within 48 hours, and 38.2% within 72 hours. Therefore, it is necessary to seize the opportunity for examination without delay.
　　2. For patients in hemorrhagic shock, blood volume should be first replenished, and gastroscopy can be performed more safely after blood pressure is somewhat stable.
　　3. Generally, there is no need for pre-washing of the stomach, but if there is excessive bleeding and it is estimated that blood clots will affect observation, the stomach can be washed with ice water and then checked.
　

　　1. No food is allowed during the bleeding period.

　　2. It is not advisable to eat for 2-3 days after bleeding stops: eat in the order of semi-liquid food -- semi-solid food (easy to digest and absorb) -- regular food (avoid hard and coarse foods, high in calories and vitamins, low in salt).

　　3. The diet should mainly include high-quality protein, such as milk, eggs, soybeans, and their products, which are particularly suitable.

　　Patients with liver cirrhosis with a tendency to hepatic encephalopathy should avoid high-protein diets to prevent the occurrence of hepatic encephalopathy.

　　4. Restrict salt intake as appropriate; salt has hydrophilic properties. If the salt content in food is high, it will reduce the excretion of water in the body, in order to prevent the exacerbation of ascites.

　　5. Avoid smoking, alcohol, strong tea, and coffee. Alcohol is mainly metabolized by the liver, causing significant damage to the liver, affecting the synthesis of coagulation factors, and easily triggering upper gastrointestinal bleeding. The harmful components in tobacco leaves have a significant irritating effect on the gastrointestinal mucosa, easily causing inflammation of the gastrointestinal mucosa, leading to dysfunction of the pyloric and lower esophageal sphincter, resulting in the reflux of bile and stomach contents, aggravating the condition.

　　6. The main diet should be high in calories, high in protein, high in vitamins, moderate in fat, non-irritating, soft and easy to digest, and rich in nutrition; avoid overeating, aim for eight parts full, eat small meals, and chew slowly while eating.

　　7. Avoid coarse, spicy, and irritating foods: Due to esophageal varices bleeding in liver cirrhosis patients, special attention should be paid to avoid hard and coarse foods to prevent bleeding; spicy, fragrant, fried, and other foods can damage the gastrointestinal mucosa and may cause upper gastrointestinal bleeding.

　　General treatment in Western medicine:

　　Rest in bed; observe the color and skin of the limbs for cold and dampness or warmth; record blood pressure, pulse, blood loss, and urine output per hour; maintain a venous access and measure central venous pressure. Keep the patient's respiratory tract clear and avoid asphyxiation when vomiting blood. Patients with massive bleeding should fast, while those with slight bleeding can consume semi-liquid food. Most patients have fever after bleeding, and antibiotics are generally not needed.

　　First, replenish blood volume

　　When hemoglobin is below 9g/dl and systolic blood pressure is below 12kPa (90mmHg), sufficient amounts of whole blood should be administered immediately. For patients with portal hypertension due to liver cirrhosis, one should be cautious of the possibility of rebleeding triggered by increased portal venous pressure due to blood transfusion. It is necessary to avoid excessive blood transfusion and fluid infusion to prevent acute pulmonary edema or to trigger a recurrence of bleeding.

　　Second, hemostatic treatment for massive upper gastrointestinal bleeding

　　1. Gastric cooling: By repeatedly lavaging the gastric cavity with 10-14℃ ice water through a gastric tube to cool the stomach. This can cause vasoconstriction, reduce blood flow, and suppress gastric secretion and digestion. The activity of fibrinolytic enzymes at the bleeding site is weakened, thereby achieving hemostasis.

　　2. Oral hemostatic agents: The bleeding of peptic ulcer is mucosal bleeding. The use of vasoconstrictors such as 8mg norepinephrine added to 150ml of ice saline for oral administration can cause strong vasoconstriction of the small arteries and achieve hemostasis. This method is not recommended for the elderly.

　　3. Inhibition of gastric acid secretion and protection of gastric mucosa: H2 receptor antagonists such as cimetidine, by inhibiting gastric acid and increasing the pH of the stomach, reduce the backdiffusion of H+, promote hemostasis, and have a good effect on the prevention and treatment of stress ulcer and acute gastric mucosal bleeding. In recent years, omeprazole, an acid inhibitor acting on the proton pump, is a blocker of H+, K+ ATPase, which can be intravenously injected in large bleeding, 40mg per time.

　　4. Endoscopic visualization for hemostasis: locally spraying 5% Monsell solution (ferric sulfate solution) can cause local stomach wall spasm, vasoconstriction around the bleeding vessels, and promote blood coagulation, thereby achieving hemostasis. Endoscopic high-frequency electrocoagulation for bleeding is suitable for persistent hemorrhage. Due to the difficulty in accurately coagulating the bleeding point with electrocoagulation, direct contact can cause transient bleeding. In recent years, endoscopic laser treatment has been widely used to coagulate tissue proteins, cause vasoconstriction and closure of small vessels, and immediately lead to mechanical vascular occlusion or intravascular thrombosis.