Anastomotic Leak

Overview

During many abdominal operations, a surgeon removes a diseased segment of bowel (or other hollow organ) and then joins the two healthy ends back together. This new connection is called an anastomosis. An anastomotic leak happens when that join does not heal and seal properly, allowing intestinal contents, digestive fluids, or stool to escape into the abdomen or chest.

An anastomotic leak is one of the most serious complications after gastrointestinal surgery because leaked contents are full of bacteria and can cause severe infection. It usually appears in the first days to weeks after an operation. Early recognition and treatment are essential, since a leak can quickly lead to widespread infection and become life-threatening.

Symptoms

A leak typically shows up after surgery as a person who is not recovering as expected or who suddenly worsens. Warning signs include:

• Fever and chills
• Worsening or severe abdominal pain
• A rapid heartbeat and fast breathing
• Nausea, vomiting, or a swollen abdomen
• Not passing gas or stool when expected
• Cloudy, foul, or increased fluid from a surgical drain
• Feeling generally and increasingly unwell

Signs of a spreading infection, such as confusion, very low blood pressure, little urine, and cold clammy skin, are an emergency and point toward sepsis.

Causes

An anastomotic leak occurs when the surgical join is unable to heal under the constant stress of being a living, moving connection carrying bowel contents. Contributing factors include:

• Poor blood supply: The joined ends need good circulation to heal; reduced blood flow weakens the connection.
• Tension on the join: A connection under strain is more likely to pull apart.
• Infection or contamination: Bacteria can undermine healing at the site.
• Patient factors: Poor nutrition, diabetes, smoking, steroid use, and a weakened immune system all impair healing.
• Technical and disease factors: The location of the join and the underlying condition being treated also matter.

Risk Factors

• Surgery low in the rectum or on the esophagus, where leaks are more common
• Poor nutrition or significant weight loss before surgery
• Diabetes
• Smoking
• Long-term steroid or immune-suppressing medication
• Emergency surgery or a contaminated surgical field

Diagnosis

Because early treatment improves outcomes, doctors look carefully for leaks in anyone recovering poorly after bowel surgery:

• Clinical monitoring: Vital signs, pain, drain output, and overall recovery are watched closely.
• Blood tests: Rising white blood cell count and inflammatory markers raise suspicion.
• CT scan: The main imaging test, often with contrast, to detect leaked fluid, air, or an abscess.
• Contrast studies: Sometimes used to show contrast escaping from the join.

Treatment

Treatment depends on how large the leak is and how sick the person is.

• Supportive care: Stopping oral intake, giving intravenous fluids and nutrition, and starting antibiotics.
• Drainage: A small, contained leak or abscess may be managed by draining the fluid through the skin.
• Surgery: A large leak or one causing widespread infection often requires another operation to control the leak, wash out the abdomen, and sometimes create a temporary stoma to divert bowel contents.
• Intensive care: Needed if the leak has caused sepsis or organ stress.

Recovery can be prolonged, and close monitoring is essential.

Prevention

• Optimize nutrition and control diabetes before planned surgery
• Stop smoking well in advance of an operation
• Follow your surgical team's pre- and post-operative instructions
• Report fever, worsening pain, or changes in drain output promptly after surgery
• Attend all follow-up appointments

When to See a Doctor

If you have had bowel, stomach, or esophageal surgery, contact your surgical team urgently if you develop a fever, worsening abdominal pain, a swollen belly, vomiting, or a change in fluid coming from a drain, or if you simply feel you are getting worse instead of better. Seek emergency care immediately if you become confused, faint, have a racing heart, cold clammy skin, or pass very little urine, as these can signal a serious, spreading infection.

Related Topics

Frequently Asked Questions

References

1. MedlinePlus, U.S. National Library of Medicine. Surgery wound infections.
2. Mayo Clinic. Colon surgery.
3. Centers for Disease Control and Prevention (CDC). Sepsis.
4. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Ostomy surgery of the bowel.