Ischemic colitis differs from ulcerative colitis and other bowel diseases. Ischemic colitis develops when blood flow to a part of the large intestine is reduced. Ischemic colitis most commonly occurs in older people with vascular disease, but can affect younger people, as well. Infections that attack the intestine, dehydration, high blood pressure and atherosclerosis, fatty buildup in the arteries that reduces blood flow to organs can all cause ischemic colitis. Symptoms include frequent bloody, loose stools and abdominal pain. During an acute attack, you cannot eat any food.
Nutrition During an Attack
All tissue needs blood flow to supply nutrients and oxygen. When blood flow is cut off by ischemic colitis, parts of the large intestine start to die. If bowel death, called gangrene, progresses, you could develop a rupture in the bowel, called a perforation. If the hole is large enough, the contents of the bowel can spill into the abdominal cavity. If you have recently eaten, stool in the intestine, which contains bacteria, can cause peritonitis. For this reason, you will not be allowed to eat anything at all during an attack. Instead, your nutrition will be supplied by intravenous fluids.
Preventing an Attack
One of the causes of ischemic bowel disease is atherosclerosis. Having high cholesterol levels can cause atherosclerosis. A diet high in saturated fats can cause or worsen high cholesterol levels. Eating a diet low in saturated fats can help reduce atherosclerosis and reduce the risk of developing ischemic colitis. The American Heart Association suggests consuming no more than 25 to 35 percent of your calories in the form of dietary fat and no more than 7 percent of your daily calories from saturated fats. A diet high in fiber also helps lower cholesterol levels. Diabetes can also lead to ischemic colitis and other vascular diseases, so keeping blood glucose levels under control may also help prevent an attack.
Eating After an Attack
If part of your bowel is badly damaged during an ischemic colitis attack, you may have scarring and narrowed areas within the intestine. You may also need to have part of the damaged colon removed; this happens in 20 percent of cases, according to Bryan Green, M.D. of the Duke University Division of Gastroenterology. If this happens you may need to adjust your diet. Only your own physician can tell you what you can and cannot eat, since the amount of damage done and the areas damaged will determine this.
Dehydration followed by hypovolemia, low blood volume, is one of the most common causes of ischemic colitis, Dr. Green states. A severe drop in blood pressure can reduce blood flow to organs. Strenuous exercise without adequate fluid intake or use of diuretics can lead to dehydration. Drinking enough fluid to stay hydrated can help prevent this type of ischemic colitis.