Intestinal Ischemia – Symptoms and Causes

Oveview

Intestinal ischemia occurs when blood flow to the intestines decreases or stops completely. This reduced blood flow means that intestinal tissues don’t receive enough oxygen, which can cause significant problems for the digestive system.

The condition can affect either the small intestine, large intestine, or both areas.

The most common cause is blockage of blood vessels, particularly arteries. Sometimes the blockage is partial, while in other cases it’s complete. Low blood pressure can also reduce blood flow to the intestines.

Without proper blood flow, intestinal tissues can’t function normally. This leads to symptoms like pain and digestive difficulties.

In severe cases, intestinal ischemia can cause:

• Permanent intestinal damage
• Tissue death
• Life-threatening complications

Treatment options exist, but they work best when the condition is caught early. If you experience sudden, severe abdominal pain, seeking immediate medical attention can significantly improve recovery chances.

Signs of Intestinal Ischemia

Quick-Onset Intestinal Blood Flow Problems

Sudden intestinal ischemia happens when blood flow to your intestines stops quickly. You might experience:

• Sharp, sudden pain in your abdomen
• A strong urge to have a bowel movement
• Frequent, forceful bowel movements
• A tender or swollen belly
• Blood in your stool
• Feeling sick and throwing up

Older adults might also become confused when this condition develops.

Slow-Developing Intestinal Blood Flow Problems

When intestinal ischemia develops gradually, you may notice:

• Stomach cramps or fullness that starts within 30 minutes of eating and lasts 1-3 hours
• Belly pain that worsens over weeks or months
• Avoiding food because eating causes pain
• Unplanned weight loss
• Loose stools
• Nausea and vomiting
• Bloating

When To Get Medical Help

Get emergency medical care if you have sudden, severe abdominal pain that makes it impossible to get comfortable or sit still. This requires immediate attention.

For other concerning symptoms, schedule an appointment with your doctor. Don’t wait until symptoms become severe before seeking help.

Causes

The intestines need blood to work properly. When blood flow slows or stops, it causes intestinal ischemia. This happens because of blocked arteries, narrowed blood vessels, low blood pressure, or blocked veins.

The large intestine (colon) and small intestine can both face this problem, but in different ways.

Problems with the Colon’s Blood Supply

This is the most common type of intestinal ischemia. It happens when part of the colon doesn’t get enough blood. Doctors don’t always know why this happens, but several things can increase risk:

• Very low blood pressure from heart failure, major surgery, trauma, or dehydration
• Blood clots or blockages in arteries leading to the colon
• A twisted bowel (volvulus) or a trapped intestine in a hernia
• Blockages from scar tissue or tumors
• Other health conditions like lupus, sickle cell anemia, or blood vessel inflammation (vasculitis)

Certain medications and substances can also trigger this problem:

• Blood vessel-narrowing drugs used for heart disease or migraines
• Birth control pills
• Cocaine or methamphetamine
• Even intense exercise like marathon running

Sudden Loss of Blood Flow to the Small Intestine

When blood flow suddenly stops to the small intestine, it causes acute mesenteric ischemia. This can damage the intestine permanently and happens in several ways:

1. Traveling Blood Clots: Clots that form in the heart can break loose and block the superior mesenteric artery. This commonly happens in people with heart failure, heart attacks, or irregular heartbeats.

2. Blockages in Main Intestinal Arteries: Often caused by fatty buildup in artery walls.

3. Reduced Blood Flow from Low Blood Pressure: May occur during shock, heart failure, or kidney failure. This type is called “nonocclusive ischemia” because there’s no actual blockage.

Ongoing Blood Flow Problems to the Small Intestine

This happens slowly over time as fatty deposits build up in artery walls. It’s sometimes called “intestinal angina” because pain typically occurs after eating.

Treatment usually isn’t needed until at least two of the three major arteries supplying the intestines become severely narrowed or blocked.

A dangerous complication can occur if a blood clot forms in an already narrowed artery, suddenly blocking it completely.

When Blood Can’t Leave the Small Intestine

Sometimes the problem isn’t with blood flowing to the intestines but with blood trying to leave.

When a vein that drains blood from the intestines gets blocked by a clot, blood backs up. This causes swelling and bleeding in the intestines.

Several conditions can cause this:

• Inflammation Problems:
  • Acute or chronic pancreas inflammation
  • Infections in the abdominal area
  • Bowel diseases like ulcerative colitis, Crohn’s disease, or diverticulitis
• Blood-Related Issues:
  • Conditions that make blood clot more easily
  • Medications like estrogen that increase clotting risk

• Injuries to the abdominal area can also lead to this problem.

When blood can’t flow out properly through the veins, it creates pressure and damages the intestinal tissue, leading to pain and potential tissue death if not treated.

Risk Factors

Several factors may raise your chance of developing intestinal ischemia:

• Age: People over 50 face a higher risk.
• Fatty Deposits in Arteries: Having atherosclerosis increases your risk. If you’ve been diagnosed with coronary artery disease, peripheral vascular disease, or carotid artery disease, you’re more vulnerable.
• Tobacco Use: Smoking cigarettes or using other smoked tobacco products raises your risk significantly.
• Heart Conditions: Congestive heart failure and irregular heartbeats like atrial fibrillation make intestinal ischemia more likely. Vasculitis (inflammation of blood vessels) can also increase risk.
• Medications: Some drugs may raise your risk, including:
  • Birth control pills
  • Medicines that affect blood vessel size (certain allergy and migraine medications)
• Blood Clotting Disorders: Conditions that make blood clots more likely, such as:
  • Sickle cell anemia
  • Factor V Leiden mutation (a genetic condition)
• Other health issues: These common conditions increase risk:
  • High blood pressure
  • Diabetes
  • High cholesterol
• Illegal drugs: Using cocaine or methamphetamine has been connected to intestinal ischemia.

Understanding these risk factors can help you and your doctor assess your personal risk level. Some factors, like smoking and drug use, can be changed, while others like age and genetic conditions cannot.

Complications

Intestinal ischemia can lead to several serious complications if not treated promptly. One of the most severe outcomes is tissue death in the intestines, also known as gangrene.

This happens when blood flow is completely blocked, depriving intestinal tissues of vital oxygen and nutrients.

Another dangerous complication is intestinal perforation. This creates a hole in the intestinal wall that allows contents to leak into the abdominal cavity. This can potentially cause peritonitis, a serious infection that requires immediate medical attention.

Even after recovery, scar tissue may form as part of the healing process. This scarring can create narrowing or blockages in the intestines. It most commonly affects the colon and rarely the small intestine.

People with breathing problems like emphysema and other smoking-related lung diseases face higher risks of complications.