Intestinal hemorrhage

　　The following are the lesions that cause intestinal hemorrhage:

　　1. Atherosclerosis: The narrowing of the vascular lumen leads to reduced blood supply to the corresponding area due to poor blood flow.

　　2. Embolism: Under conditions such as hypertensive heart disease, rheumatic heart disease, infectious endocarditis, myocardial infarction, atrial fibrillation, trauma, fracture, and long-term bed rest, because the main trunk of the superior mesenteric artery is large in diameter and forms an oblique angle with the abdominal aorta, it is very easy to accept emboli from the heart and cause embolism. The incidence rate accounts for about 50% of acute intestinal obstruction.

　　3. Systemic vascular lesions: This is also one of the local manifestations. For example, when nodular polyarteritis, systemic lupus erythematosus, and other immune system diseases occur, the small arteries of the intestines are involved, leading to poor blood supply to the corresponding intestinal tract and ischemic changes.

　　The clinical manifestations of bleeding depend on the nature, location, and amount and speed of blood loss of the bleeding lesion, as well as the patient's age, renal and cardiac function, and other systemic conditions. Complications include: 1 Hemorrhagic peripheral circulatory failure: Large-scale bleeding in the digestive tract can lead to acute peripheral circulatory failure. Large blood loss, uncontrolled bleeding, or untimely treatment can lead to a reduction in tissue blood perfusion and cell oxygen consumption, which can lead to hypoxia. Metabolic acidosis and the accumulation of metabolic products can cause peripheral vasoconstriction, extensive damage to capillaries, and a large amount of body fluid congestion in the abdominal cavity, bones, and surrounding tissues, leading to a sharp reduction in effective blood volume, severely affecting the blood supply to the heart, brain, and kidneys, and finally leading to irreversible shock and death. 2 Azotemia: It can be divided into three types: intestinal, renal, and pre-renal azotemia. 3 Fever: Most patients will have a low fever within 24 hours after a large amount of bleeding.

　　Intestinal ischemia leads to a reduction or loss of blood supply to the intestines, which cannot meet the physiological needs of the intestines. The intestinal wall may suffer from congestion, edema, or ulcers, and in severe cases, necrosis, hemorrhage, perforation, and peritonitis may occur. Ischemic bowel disease (ischemic bowel disease) is a disease caused by ischemia and hypoxia of the intestinal wall, which eventually leads to infarction. This disease is more common in elderly patients with atherosclerosis and heart failure. The lesions are mostly segmental and centered around the sigmoid flexure of the colon. The direct cause of colonic ischemia is often the occlusion and stenosis of mesenteric arteries and veins, especially the superior mesenteric artery due to atherosclerosis or thrombosis. Heart failure and shock can cause a decrease in blood pressure, and insufficient local blood supply to the intestines can also be a cause of the disease. The general symptoms include abdominal pain, usually diffuse and persistent. Loss of appetite, nausea, and others.

　　Pay main attention to moderate diet, avoid overeating and binging, and reduce the intake of high-fat foods to prevent thrombosis. Participate in physical exercise regularly, as it can dilate blood vessels, increase vascular elasticity, promote blood circulation, and prevent the occurrence of thrombosis. After intestinal bleeding, the food therapy is the same as that for gastric ulcer, but it is necessary to have a long-term cautious diet and avoid the following foods: (1) Stimulating foods: such as alcohol, coffee.

　　Pay main attention to moderate diet, avoid overeating and binging, and reduce the intake of high-fat foods to prevent thrombosis. Participate in physical exercise regularly, as it can dilate blood vessels, increase vascular elasticity, promote blood circulation, and prevent the occurrence of thrombosis. After intestinal bleeding, the food therapy is the same as that for gastric ulcer, but it is necessary to have a long-term cautious diet and avoid the following foods: (1) Stimulating foods: such as alcohol, coffee, curry, pepper, chili, mustard powder. Astringent and hot foods like lychee, and moistening tonics like mutton should be avoided. (2) Cold and cool foods: such as crabs, clams, oysters, water ducks, kelp, mung beans, bitter melon, persimmons, etc. (3) Sour foods: such as vinegar, tomatoes, lemons, plums, hawthorns, etc. (4) Tough and difficult-to-digest foods: such as squids, abalones, shark fins, peanuts, cashews, etc., as well as chicken, duck, and meats. After chewing, spit out the残渣 and do not force swallowing. (5) Too cold or too hot drinks: Both are not suitable; the temperature of food should be neither too cold nor too hot.

　　Since the symptoms of ischemic colitis are non-specific, early diagnosis based on clinical presentation is more difficult.

　　Patients with underlying conditions that may lead to ischemic colitis should consider the possibility of ischemic colitis if they experience persistent or sudden abdominal pain. If there are no special findings after examination, the possibility of ischemic colitis should be considered. The presence of occult blood in gastrointestinal secretions or blood in stools, as well as elevated peripheral white blood cell counts, can be helpful for diagnosis. Severe abdominal pain, acute abdomen, or signs of shock should alert for the possibility of intestinal perforation. Emergency endoscopic examination is of diagnostic significance, especially during the period of hematochezia, and is crucial for early diagnosis. It can also determine the extent and stage of the lesion, obtain histological examination, and help differentiate from other inflammatory bowel diseases and colon cancer. The following are the precautions for endoscopic examination:

　　1. Persistent abdominal pain, hematochezia, and peritoneal irritation symptoms should raise the suspicion of gangrenous conditions, and endoscopy is contraindicated.

　　2. Blind sliding of the endoscope, hooking, and detaching loops should be prohibited to avoid exacerbating bleeding and even perforation.

　　3. When the air pressure injected into the colonoscopy exceeds 3.9 kPa (30 mmHg), the high intestinal pressure can lead to thinning of the intestinal wall, reduced blood flow, and exacerbation of colonic ischemia. Injecting CO2 gas can dilate the vessels, which is beneficial for the blood supply to the colon.

　　4. Submucosal bleeding is usually quickly absorbed or replaced by ulcers, so it is very important to perform endoscopic examination within 72 hours after onset. Necessary tests for suspected cases may include serological tests, CT scans, angiography, color Doppler ultrasound, and endoscopy. Color Doppler ultrasound is a non-invasive and relatively sensitive examination method. Some scholars [4] conducted color Doppler ultrasound on 24 cases of ischemic colitis and found that the sensitivity for diagnosing ischemic colitis reached 82%, the specificity reached 92%, and the positive predictive value was 81%. Therefore, color Doppler ultrasound is of great significance for the early diagnosis and prognosis monitoring of ischemic colitis.

　　It is advisable to avoid all spicy and刺激性 foods, coarse grains, and foods rich in residue. It is not recommended to drink broths, chicken soups, strong tea, and other beverages that can stimulate the secretion of intestinal acid. To neutralize intestinal acid and reduce the burden on the intestines, it is suggested to eat small meals more frequently. Different dietary approaches can be adopted based on the severity of the condition.

　　Stage 1 diet: Starting from 7 o'clock in the morning, eat every 2 hours, eat 8 times a day. The content of the diet is basically similar to that of liquid diet, but meat soup, chicken soup, strong tea, and other foods should be avoided. To neutralize stomach acid and supplement nutrition, milk can be drunk 2 to 3 times a day, and milk-intolerant patients can use soy milk instead. Eat 3 to 4 times a day, and can eat tofu pudding, congee, lotus root starch, cooked egg soup, fruit water or tomato juice and vegetable soup, etc.

　　Stage 2 diet: Starting from 7 o'clock in the morning, eat every 2 to 2.5 hours, every day

　　Eat 7 times a day. The content of the diet is basically similar to semi-liquid diet, but vegetables puree and various fresh soups should be avoided. Milk or soy milk should be drunk 1 to 2 times a day or 2 to 3 times a day, and other semi-liquid suitable foods can be added.

　　Stage 3 diet: Eat 6 times a day, in addition to the three main meals of breakfast, lunch, and dinner, another 3 snacks should be added. Milk or soy milk should still be drunk once a day; eat less and more often; the content of the diet is basically the same as that of low residue diet, and 1 time of fruit water, vegetable soup, or tomato juice can be added to the 3 meal snacks.

　　Since the etiology and pathogenesis of the disease have not been elucidated, the goal of internal medicine treatment is to control acute attacks, alleviate the condition, reduce recurrence, and prevent complications. At present, it is not possible to cure the disease, and the treatment depends on the extent and severity of the lesion. It mainly includes general treatment, nutritional support treatment, symptomatic treatment, and drug treatment. Drug treatment includes aminosalicylic acid derivatives, such as sulfasalazine and mesalazine (5-aminosalicylic acid), corticosteroids, immunosuppressants, and traditional Chinese medicine. The new developments in internal medicine treatment in recent years mainly include the following aspects: the application of enteral nutrition, the application of new 5-aminosalicylic acid preparations, the application of other new formulations, and the use of immunosuppressants.

　　Due to the close relationship between this disease and gastrointestinal nutrition, patients may have deficiencies in various nutrients, such as proteins, vitamins, electrolytes, and trace elements. Conversely, malnutrition can affect the effectiveness of drug treatment. Therefore, in recent years, fat-free and residue-free elemental diet has become an important auxiliary treatment method. Easy-to-digest, low-fiber, and nutritious foods should be provided, and milk and dairy products should be avoided. During the acute phase, liquid food should be given, and severe cases should be fasting. Nutritional treatment should be administered intravenously to allow the intestines to rest.

　　Patients with fulminant and acute onset should rest in bed, and those with excessive mental tension can be given appropriate sedatives; patients with marked abdominal pain or diarrhea can be given small doses of atropine, anisodamine (654-2), and other drugs, but the use of high doses may pose a risk of acute colonic dilation.

　　Patients with severe or chronic diseases such as anemia, dehydration, and malnutrition should be given blood transfusions, fluid replacement, and systemic supportive treatment as appropriate. The use of protein synthesis hormones can improve the general condition, increase appetite, and accelerate the healing of ulcers. Special attention should be paid to the balance of water and electrolytes, the supplementation of various vitamins, which is conducive to the recovery and improvement of the condition.

　　Sulfonamides: The first choice of sulfonamides that are not easily absorbed in the gastrointestinal tract is sodium salicylate (sodium azosulfapyridine), which has the best effect. This drug is decomposed into sulfapyridine and mesalazine in the intestine by bacteria, where mesalazine is the main active ingredient, with a special affinity for colonic tissue walls and anti-inflammatory effects. The new 5-aminosalicylic acid preparations mainly have two types: one with enteric-coated capsules, which can delay the release of the drug, such as mesalazine (Edessa); the other is a sustained-release preparation, such as mesalazine (Podsol), which releases the drug in a time-dependent manner from the duodenum to the colon. Whether it is a controlled-release or sustained-release preparation, the drug concentration in the colon is significantly higher than that in the small intestine. Mesalazine (5-aminosalicylic acid) is mainly used for the active and remission stages of mild to moderate ulcerative colitis. It is especially suitable for patients who cannot tolerate or are allergic to sulfasalazine. The efficacy of aminosalicylic acid类药物 depends on the drug concentration at the site of the lesion, so in recent years, it is advocated to use local therapy for patients with distal ulcerative colitis, such as drug enema or suppository therapy, which can achieve good therapeutic effects with significantly reduced side effects. In particular, the mesalazine (5-aminosalicylic acid) suppository has a good therapeutic effect on rectal and anal inflammation with minimal side effects.

　　Antibiotics: Penicillin, chloramphenicol, gentamicin, cephalosporins, and other antibiotics can be used in secondary infections. To avoid exacerbating gastrointestinal symptoms, intravenous administration is generally chosen. Metronidazole or tinidazole can inhibit intestinal anaerobic bacteria and have immunosuppressive and effects on leukocyte chemotaxis. It is believed that this drug can significantly alleviate symptoms of urgency and frequency, and has a marked therapeutic effect on patients with perianal diseases and fistulas. The dose is 0.4g, 3 times a day, taken orally, for a course of 3-6 months. The effective rate in patients with a course of more than 1 year is 60%-70%.

　　Glucocorticoids and adrenocorticotropic hormone (ACTH): The recent efficacy is good, with an effective rate of up to 90%, capable of inhibiting inflammation and immune responses, and alleviating poisoning symptoms. Generally applicable in cases with ineffective sulfonamide drugs, acute onset, or fulminant type, but it is not suitable for use in patients with peritonitis or the formation of intraperitoneal abscesses. Generally, prednisone (Prednisone) 40-60mg/d can be taken orally in 3-4 doses. After the condition is controlled, the dose is gradually reduced to 10-15mg/d, and the medication is usually stopped after maintaining for about half a year. To reduce the recurrence after drug withdrawal, mesalazine (5-ASA) is administered orally during the dose reduction process or after withdrawal. In fulminant and severe exacerbation stages, intravenous infusion of ACTH or glucocorticoids can be administered, with the former being more effective, with a dosage of 25-50U/d; the dosage of hydrocortisone is 200-300mg/d, or methylprednisolone (Methylprednisolone sodium succinate) 40-80mg/d. The course of treatment is generally 10-14 days, and the dose is gradually reduced after the condition is controlled, and then oral prednisone (Prednisone) and other preparations can be maintained.

　　Immunomodulatory drugs: For patients who are insensitive to glucocorticoid therapy or have a dependence on glucocorticoids, immunosuppressants can be considered. Immunomodulatory drugs mercaptopurine (6-mercaptopurine) and azathioprine can selectively act on T lymphocytes, but their effects are slow, usually appearing after 3-6 months of medication, but they have significant side effects. Patients who are ineffective to sulfonamide drugs and corticosteroid therapy can be cautiously tried. The dosage of 6-mercaptopurine is 1.5mg/(kg·d), taken orally in divided doses; azathioprine 1.5-2.5mg/(kg·d), taken orally in divided doses, the course of treatment is about one year. If used in combination with glucocorticoids, the dosage of both should be reduced accordingly. Cyclosporin has no inhibitory effect on bone marrow and is effective for severe active ulcerative colitis, often used for patients who fail to respond to corticosteroid therapy, the initial dose is 2-4mg/(kg·d), administered intravenously as a continuous infusion, or 8mg/(kg·d) orally.

　　Other drugs: such as disodium cromoglycate can prevent mast cells and eosinophils from degranulating, thereby inhibiting the release of serotonin and slow-reacting substances, reducing antigen-antibody reactions, and can alleviate symptoms; calcium channel blockers, such as verapamil (isoptin), nifedipine, cilnidipine, etc., can reduce intestinal secretion and relieve diarrhea; traditional Chinese medicine berberine (coptis), Sophora flavescens, Alisma orientale, Yunnan Baiyao, tin powder, etc., have certain curative effects when used locally for treatment.