What is an Anastomotic Leak?

An anastomotic leak is a breakdown along an anastomosis which causes fluids to leak. Anastomoses are used when a hollow organ such as the intestine needs to be severed and reconnected to allow fluids to flow through it, most commonly because part of the organ needs to be removed. The gastrointestinal tract is not the only site where an anastomosis can be performed; it is also possible to sever and reconnect blood vessels in this way, and to perform similar procedures in the urinary tract. Making a good anastomosis requires skill on the part of the surgeon.

When a surgeon must perform an anastomosis, care is taken at every step of the way. Historically the procedure was done with sutures, although glues and staples may be used in some areas today. Once the surgeon is satisfied that the join is complete, it is tested to confirm that it does not leak, and then the surgical site is closed so the patient can be brought out of anesthesia.

Leaks can develop at the site of an anastomosis for a number of reasons. One cause for an anastomotic leak is a mistake on the part of the surgeon which leaves the join incomplete or weakens it, allowing it to leak under pressure. Another reason is poor wound healing; sometimes surgical sites don't heal well despite the best efforts on the part of the surgeon and when that site is an anastomosis, it can leak. An anastomotic leak can also develop as a result of infection, fluid buildup, or unexpected stress on the join.

This postoperative complication is a known risk when an anastomosis is performed and patients are usually monitored for the early signs of a leak. Patients can report pain, bloating, or heat which suggests that an infection may be occurred. A medical imaging study can be used to diagnose the leak, usually with the assistance of a tracer. If an anastomosis is leaking, the tracer will leak out as well and show up on x-ray in places where it should not be.

Treatment options for an anastomotic leak vary, depending on the nature of the leak and the location. Sometimes it is necessary to perform a surgical repair to correct the leak. For some patients, this may require the temporary placement of a tube for drainage to allow the site to heal before performing surgery to repair the damaged anastomosis. In other cases, simply draining the area of excess fluid relieves the stress and allows the body to heal so that the anastomotic leak resolves.