Risks of Gastric Bypass Surgery: Anastomotic Leaking

If you are severely obese and have had trouble losing weight, your doctor may recommend weight-loss surgery. Weight-loss surgery, also known as bariatric surgery, is an effective way to lose weight and reduce the risk for weight-related problems such as heart disease, diabetes, sleep apnea, and arthritis.

As with any surgery, gastric bypass carries some risks. Complications of surgery include infection, blood clots, and internal bleeding. Another risk is that the anastomosis, the new connection created in your intestines during the bypass surgery, will leak. Leaking of digestive juices and partially digested food through an anastomosis is one of the most serious complications after bypass surgery.

Gastric bypass overview

Gastric bypass is the most common type of weight-loss surgery. During bypass surgery, a loop of your intestine is cut and brought up and reconnected to an area adjacent to your stomach. Food is then redirected past your stomach to an area farther down in your digestive system. Because food will now bypass your stomach, your body does not absorb as many calories, and you will feel full faster after eating.  

Your doctor may suggest this surgery if you have a body mass index (BMI) of 40 or higher or if you have a BMI of 35 or higher along with serious weight-related, health problems. A BMI of more than 40 typically means that you are at least 100 pounds overweight.

Symptoms of anastomotic leaking

Anastomotic leaks occur in 2 to 6 percent of bypass procedures, depending on the type of surgery. A leak may happen up to a month later, but most develop at about three days after surgery. Symptoms of an anastomotic leak include:

  • Rapid heart rate

  • Fever

  • Abdominal pain

  • Drainage from a surgical wound

  • Nausea

  • Pain in the shoulder area

  • Low blood pressure

  • Decreased urine output

The more obese you are, the more at risk you are for an anastomotic leak. Other risk factors include being male, having other medical problems besides obesity, and having a history of previous abdominal surgery.

Diagnosis and treatment of anastomotic leaking

The most reliable diagnostic test for anastomotic leaking is an upper GI series with a CT scan. This involves putting dye inside the upper digestive area and then taking computer-guided X-rays to see if the dye is leaking through the anastomosis. If you have a negative exam but still have symptoms, your doctor may do an emergency operation to look for a leak.

The medical team treating an anastomotic leak will likely take these steps:

  • Give you antibiotics through an IV.

  • Drain any infection caused by the leak, repair the leak, or make a new anastomosis.

  • Stop all oral feedings. You may be fed through a tube that goes directly into your intestine until the leak has healed.

Risks of anastomotic leaking         

A leaking anastomosis may cause bleeding and infection until it is treated. Long-term complications may include scarring or a drainage tract through the skin called a fistula. Pneumonia is another dangerous complication, because digestive juices can spill into the lungs. 

If you are considering gastric bypass surgery for obesity, discuss the procedure carefully with your doctor. The overall risk of serious complications should be weighed against the risk of continued obesity. Remember that gastric bypass surgery works best when combined with long- term, healthy lifestyle choices involving good nutrition and regular exercise. 

Medical Reviewer: Jones, Niya, MD Kidd, India, RN, BSN, MBA Last Annual Review Date: 2012-03-17 Copyright: © 2000-2012 Krames StayWell, 780 Township Line Road, Yardley, PA 19067. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

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