Senile ischemic colitis

　　Ischemic colitis is more common in the middle-aged and elderly, and is often located in the splenic flexure of the colon, descending colon, and sigmoid colon, due to relatively poor blood supply in these areas. It is often caused by

　　The blood supply to the colon mainly comes from the superior mesenteric artery and the inferior mesenteric artery, while the local circulation within the intestinal wall is composed of a series of paired small vessels. The intestinal mucosa receives 50% to 75% of the flow from the intestinal wall, so the intestinal mucosa is most affected by changes in blood flow. The left half of the colon, which is at the junction of the blood supply areas of the two artery terminal branches, is prone to insufficient blood supply, so the most common site of onset is the left half of the colon.
 

　　The complications of senile ischemic colitis mainly include intestinal perforation, peritonitis, and so on.

　　1. Intestinal perforation

　　It refers to the process of intestinal contents leaking into the peritoneal cavity due to intestinal wall lesions penetrating the intestinal wall, which is one of the serious complications of many intestinal diseases. It can cause severe diffuse peritonitis, mainly manifested as severe abdominal pain, abdominal distension, and symptoms and signs of peritonitis. In severe cases, it can lead to shock and death.

　　2. Peritonitis

　　It is a common serious surgical disease caused by bacterial infection, chemical irritation, or injury. Most of them are secondary peritonitis, originating from organ infection in the peritoneal cavity, such as necrosis, perforation, trauma, etc.

　　Ischemic colitis is usually spontaneous, and its clinical manifestations vary due to the severity, extent of involvement, the speed of ischemic damage, and the degree of tolerance of the intestinal wall to hypoxia. It is usually seen in patients over 60 years old. Patients with no history of colonic disease suddenly develop acute abdominal symptoms, and the most consistent symptoms and signs are: abdominal pain, diarrhea, and hematochezia, which usually involves a small amount of bleeding; pain attacks are acute, spasmodic, often localized to the lower left abdomen; defecation is urgent and often accompanied by pain; secondary symptoms such as intestinal obstruction may occur, such as anorexia, nausea, and vomiting; abdominal examination often shows abdominal distension and tenderness corresponding to the ischemic colon; generally, there is no significant fever. Rectal examination often shows hematochezia, and cardiovascular examination generally shows no positive findings.

　　The etiology of elderly ischemic colitis is complex, and prevention should be multi-faceted. Prevention should focus on the following aspects:

　　First, third-level prevention

　　1. First-level prevention

　　This disease is more common due to atherosclerosis, so early control of hypertension, coronary heart disease, and diabetes can delay the occurrence of this disease.

　　2. Second-level prevention

　　The symptoms and signs of this disease do not match, such as in elderly patients with diseases such as hypertension, atherosclerosis, diabetes, who suddenly develop abdominal colic, diarrhea, and accompany with mucous purulent stools, this disease should be considered first in order to receive early treatment.

　　3. Third-level prevention

　　(1) Patients in or discharged from the hospital should undergo vasodilator therapy, regularly review blood glucose and blood lipids, control hypertension, and reduce or avoid the formation of thrombi and the occurrence of ischemic colitis.

　　(2) For patients who have undergone surgical treatment, especially those with intestinal resection, attention should be paid to parenteral nutrition. After the patient can eat, attention should be paid to dietary adjustment and the adjustment of nutritional status.

　　Second, risk factors

　　Ischemia of the intestinal wall is mainly divided into three aspects: obstruction of arterial inflow, obstruction of venous return, and insufficient perfusion. Specific risk factors include the following:

　　1. Mesenteric artery stenosis or occlusion

　　It can be due to mesenteric arteriostenosis caused by atherosclerosis, or it can be caused by small emboli from the detachment of atherosclerotic plaques, leading to occlusion of the terminal arteries of the intestinal tract.

　　2. Non-occlusive mesenteric ischemia

　　The main cause is the decrease in cardiac output due to diseases such as myocardial infarction, myocardial disease, congestive heart failure, arrhythmia, or hypovolemic shock. There are also reports that in patients with heart disease, the administration of digitalis in high doses can cause mesenteric arteriolar constriction, blood flow obstruction, and lead to this disease. Other drugs that affect the microcirculation of colonic blood vessels may also trigger the occurrence of this disease.

　　3、Formation of mesenteric vein thrombosis

　　It is mainly a hypercoagulable state caused by certain blood diseases, intra-abdominal sepsis, abdominal trauma, or the use of estrogen-containing contraceptives.

　　4、Intestinal lumen factors

　　On the basis of ischemia and pre-ischemic state (chronic circulatory obstruction) due to atherosclerosis and other vascular lesions, and the rise of intraluminal pressure caused by certain reasons, accompanied by a temporary strong peristalsis, such as in severe constipation or intestinal spasm, the intestinal arteriovenous shunt opens, leading to a decrease in blood flow in the mesenteric blood vessels. If there is bacterial invasion of the colonic mucosa, it further aggravates the damage caused by ischemia.

　　5、Certain systemic diseases

　　Such as nodular perivascularitis, systemic lupus erythematosus, rheumatoid arthritis, dermatomyositis, Behcet's syndrome, allergic purpura, and others involving small vessel lesions, diabetes, etc.

　　Clinically, ischemic colitis in the elderly is mainly diagnosed by imaging and colonoscopy, and the results of laboratory tests only play a supplementary role.

　　First, imaging examination

　　1、Abdominal flat film

　　It can cause signs such as edema and thickening of the intestinal wall, intestinal distension, and peritoneal effusion.

　　2、Barium enema examination

　　It is of great significance and is considered by some to be the first choice for examination.

　　Second, fiber colonoscopy

　　Early diagnosis of this disease is of great value, but it should be noted that coloscopy is not suitable for gangrenous colitis, and its microscopic appearance is as follows:

　　1、急性期

　　Within 72 hours of onset, there is mucosal congestion and edema, scattered bleeding points, superficial erosion, about half of which may have superficial ulcers, the lesions are segmentally distributed, and the boundaries are clear; biopsy shows inflammatory cell infiltration,纤维素样 thrombosis in small blood vessels, destruction of glands, and focal hemorrhage.

　　2、亚急性期

　　From 72 hours to 7 days after onset, typical longitudinal ulcers can be seen, and there are obvious inflammatory exudates; biopsy shows tissue necrosis and granulation tissue repair.

　　3、慢性期

　　Two to two months after onset, only mild inflammatory changes can be seen under the microscope, without characteristics. Biopsy shows overall degenerative changes, fibrous tissue and granulation tissue hyperplasia, and there is also a more specific iron-containing hemosiderin deposition.

　　Patients with ischemic colitis in the elderly should have a light diet, rationally balanced nutrition, eat more vegetables and fruits, pay attention to nutritional balance, and at the same time limit the intake of the following foods.

　　Avoid刺激性食物

　　It is advisable to avoid spicy and stimulating foods such as chili, mustard, and alcohol. Also, reduce the intake of garlic, ginger, and scallions. Do not consume foods that are too cold or too hot. In summer, it is especially important to avoid cold drinks and foods taken directly from the refrigerator.

　　Reduce the intake of rough fiber foods

　　Avoid foods rich in rough fibers and coarse processed foods. Large amounts of rough fiber foods can stimulate the intestines and affect the absorption of nutrients, which can worsen the condition for patients who are already malnourished. Therefore, it is best to limit the intake of fibrous foods such as leeks, celery, sweet potatoes, radishes, coarse grains, and dried beans. During the active phase of the disease, it is advisable to avoid raw vegetables and fruits, which can be consumed in the form of vegetable broth, pureed vegetables, fruit juice, and pureed fruits. It is not recommended to cook with large pieces of meat; instead, use minced meat, diced meat, shredded meat, minced meat, steamed egg custard, and boiled eggs frequently.

　　The treatment of elderly ischemic colitis depends on the etiology, sensitivity, and severity of the disease. Once the diagnosis is confirmed and clinical examination does not suggest necrosis or perforation of the intestines, conservative therapy is adopted.
　　1. Supportive Treatment
　　In general, if the patient has abdominal pain, parenteral nutrition should be administered to allow the intestines to rest and to discontinue medications that can cause intestinal ischemia as soon as possible. Actively improve systemic and local blood circulation, replenish blood volume, correct heart failure, arrhythmias, shock, and other conditions.
　　2. Prevention and Treatment of Intestinal Infection
　　Broad-spectrum antibiotics effective against both aerobic bacteria and anaerobic Escherichia coli can be used for secondary infection.
　　3. Oxygen Supply and Intestinal Decompression
　　If there is intestinal obstruction, gastrointestinal decompression should be performed, and oxygen should be supplied continuously to help improve the overall and local conditions.
　　4. Vasodilator Drug Therapy
　　It has been confirmed that cocaine, nitroglycerin, isoproterenol, bradykinin, histamine, serotonin, vasoactive intestinal peptide, and glucagon can dilate colonic blood vessels and increase colonic blood flow or tissue oxygen supply. Low molecular weight dextran should be administered appropriately according to the condition.
　　5. Angiography
　　Cocaine 1.0mg/ml can be administered through a catheter, which can directly act on blood vessels that are ischemic and accompanied by mesenteric artery spasm, causing them to dilate and can maintain infusion for 24 hours.
　　6. Rehabilitation Treatment
　　Patients in or discharged from the hospital should undergo vasodilation treatment, regularly review blood glucose and blood lipids, control hypertension, reduce or avoid the formation of thrombi and the occurrence of ischemic colitis. Patients who have undergone surgical treatment, especially those with intestinal resection, should pay attention to parenteral nutrition, and after the patient can eat, attention should be paid to dietary adjustment and the adjustment of nutritional status.
　　7. Optimal Plan
　　Closely observe vital signs and abdominal signs, and initially treat with vasodilator drugs as the main conservative treatment. If surgical indications arise, surgery should be performed as soon as possible.
　　Early detection and timely treatment of elderly ischemic colitis are beneficial in general prognosis. Poor prognosis is observed in cases with intestinal perforation or peritonitis.